From 4b4ee0dc63abddffdc64355429e4ea9ccaa4d36d Mon Sep 17 00:00:00 2001 From: marha Date: Sun, 9 May 2010 21:30:23 +0000 Subject: svn merge -r577:HEAD ^/branches/released . --- xorg-server/mi/miarc.c | 7284 ++++++++++++++++++++++++------------------------ 1 file changed, 3594 insertions(+), 3690 deletions(-) (limited to 'xorg-server/mi') diff --git a/xorg-server/mi/miarc.c b/xorg-server/mi/miarc.c index 4a4a05dc0..bdc08459e 100644 --- a/xorg-server/mi/miarc.c +++ b/xorg-server/mi/miarc.c @@ -1,3690 +1,3594 @@ -/*********************************************************** - -Copyright 1987, 1998 The Open Group - -Permission to use, copy, modify, distribute, and sell this software and its -documentation for any purpose is hereby granted without fee, provided that -the above copyright notice appear in all copies and that both that -copyright notice and this permission notice appear in supporting -documentation. - -The above copyright notice and this permission notice shall be included in -all copies or substantial portions of the Software. - -THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR -IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, -FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE -OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN -AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN -CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. - -Except as contained in this notice, the name of The Open Group shall not be -used in advertising or otherwise to promote the sale, use or other dealings -in this Software without prior written authorization from The Open Group. - - -Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts. - - All Rights Reserved - -Permission to use, copy, modify, and distribute this software and its -documentation for any purpose and without fee is hereby granted, -provided that the above copyright notice appear in all copies and that -both that copyright notice and this permission notice appear in -supporting documentation, and that the name of Digital not be -used in advertising or publicity pertaining to distribution of the -software without specific, written prior permission. - -DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING -ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL -DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR -ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, -WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, -ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS -SOFTWARE. - -******************************************************************/ -/* Author: Keith Packard and Bob Scheifler */ -/* Warning: this code is toxic, do not dally very long here. */ - -#ifdef HAVE_DIX_CONFIG_H -#include -#endif - -#include -#include -#include -#include "misc.h" -#include "gcstruct.h" -#include "scrnintstr.h" -#include "pixmapstr.h" -#include "windowstr.h" -#include "mifpoly.h" -#include "mi.h" -#include "mifillarc.h" -#include - -#ifdef _MSC_VER -#define hypot _hypot -#endif - -static double miDsin(double a); -static double miDcos(double a); -static double miDasin(double v); -static double miDatan2(double dy, double dx); - -#ifndef HAVE_CBRT -static double -cbrt(double x) -{ - if (x > 0.0) - return pow(x, 1.0/3.0); - else - return -pow(-x, 1.0/3.0); -} -#endif - -/* - * some interesting sematic interpretation of the protocol: - * - * Self intersecting arcs (i.e. those spanning 360 degrees) - * never join with other arcs, and are drawn without caps - * (unless on/off dashed, in which case each dash segment - * is capped, except when the last segment meets the - * first segment, when no caps are drawn) - * - * double dash arcs are drawn in two parts, first the - * odd dashes (drawn in background) then the even dashes - * (drawn in foreground). This means that overlapping - * sections of foreground/background are drawn twice, - * first in background then in foreground. The double-draw - * occurs even when the function uses the destination values - * (e.g. xor mode). This is the same way the wide-line - * code works and should be "fixed". - * - */ - -#undef max -#undef min - -_X_INLINE static int max (const int x, const int y) -{ - return x>y? x:y; -} - -_X_INLINE static int min (const int x, const int y) -{ - return xlineWidth; - int a0, a1, startAngle, endAngle; - miArcFacePtr temp; - - if (!l) - l = 1; - - if (tarc.width == 0 || tarc.height == 0) { - drawZeroArc (pDraw, pGC, &tarc, l, left, right); - return; - } - - if (pGC->miTranslate) { - tarc.x += pDraw->x; - tarc.y += pDraw->y; - } - - a0 = tarc.angle1; - a1 = tarc.angle2; - if (a1 > FULLCIRCLE) - a1 = FULLCIRCLE; - else if (a1 < -FULLCIRCLE) - a1 = -FULLCIRCLE; - if (a1 < 0) { - startAngle = a0 + a1; - endAngle = a0; - temp = right; - right = left; - left = temp; - } else { - startAngle = a0; - endAngle = a0 + a1; - } - /* - * bounds check the two angles - */ - if (startAngle < 0) - startAngle = FULLCIRCLE - (-startAngle) % FULLCIRCLE; - if (startAngle >= FULLCIRCLE) - startAngle = startAngle % FULLCIRCLE; - if (endAngle < 0) - endAngle = FULLCIRCLE - (-endAngle) % FULLCIRCLE; - if (endAngle > FULLCIRCLE) - endAngle = (endAngle-1) % FULLCIRCLE + 1; - if ((startAngle == endAngle) && a1) { - startAngle = 0; - endAngle = FULLCIRCLE; - } - - drawArc (&tarc, l, startAngle, endAngle, right, left); -} - -/* - -Three equations combine to describe the boundaries of the arc - -x^2/w^2 + y^2/h^2 = 1 ellipse itself -(X-x)^2 + (Y-y)^2 = r^2 circle at (x, y) on the ellipse -(Y-y) = (X-x)*w^2*y/(h^2*x) normal at (x, y) on the ellipse - -These lead to a quartic relating Y and y - -y^4 - (2Y)y^3 + (Y^2 + (h^4 - w^2*r^2)/(w^2 - h^2))y^2 - - (2Y*h^4/(w^2 - h^2))y + (Y^2*h^4)/(w^2 - h^2) = 0 - -The reducible cubic obtained from this quartic is - -z^3 - (3N)z^2 - 2V = 0 - -where - -N = (Y^2 + (h^4 - w^2*r^2/(w^2 - h^2)))/6 -V = w^2*r^2*Y^2*h^4/(4 *(w^2 - h^2)^2) - -Let - -t = z - N -p = -N^2 -q = -N^3 - V - -Then we get - -t^3 + 3pt + 2q = 0 - -The discriminant of this cubic is - -D = q^2 + p^3 - -When D > 0, a real root is obtained as - -z = N + cbrt(-q+sqrt(D)) + cbrt(-q-sqrt(D)) - -When D < 0, a real root is obtained as - -z = N - 2m*cos(acos(-q/m^3)/3) - -where - -m = sqrt(|p|) * sign(q) - -Given a real root Z of the cubic, the roots of the quartic are the roots -of the two quadratics - -y^2 + ((b+A)/2)y + (Z + (bZ - d)/A) = 0 - -where - -A = +/- sqrt(8Z + b^2 - 4c) -b, c, d are the cubic, quadratic, and linear coefficients of the quartic - -Some experimentation is then required to determine which solutions -correspond to the inner and outer boundaries. - -*/ - -typedef struct { - short lx, lw, rx, rw; -} miArcSpan; - -typedef struct { - miArcSpan *spans; - int count1, count2, k; - char top, bot, hole; -} miArcSpanData; - -typedef struct { - unsigned long lrustamp; - unsigned short lw; - unsigned short width, height; - miArcSpanData *spdata; -} arcCacheRec; - -#define CACHESIZE 25 - -static void drawQuadrant(struct arc_def *def, struct accelerators *acc, - int a0, int a1, int mask, miArcFacePtr right, - miArcFacePtr left, miArcSpanData *spdata); - -static arcCacheRec arcCache[CACHESIZE]; -static unsigned long lrustamp; -static arcCacheRec *lastCacheHit = &arcCache[0]; -static RESTYPE cacheType; - -static int -miFreeArcCache (pointer data, XID id) -{ - int k; - arcCacheRec *cent; - - if (id) - cacheType = 0; - - for (k = CACHESIZE, cent = &arcCache[0]; --k >= 0; cent++) - { - if (cent->spdata) - { - cent->lrustamp = 0; - cent->lw = 0; - xfree(cent->spdata); - cent->spdata = NULL; - } - } - lrustamp = 0; - return Success; -} - -static void -miComputeCircleSpans( - int lw, - xArc *parc, - miArcSpanData *spdata) -{ - miArcSpan *span; - int doinner; - int x, y, e; - int xk, yk, xm, ym, dx, dy; - int slw, inslw; - int inx = 0, iny, ine = 0; - int inxk = 0, inyk = 0, inxm = 0, inym = 0; - - doinner = -lw; - slw = parc->width - doinner; - y = parc->height >> 1; - dy = parc->height & 1; - dx = 1 - dy; - MIWIDEARCSETUP(x, y, dy, slw, e, xk, xm, yk, ym); - inslw = parc->width + doinner; - if (inslw > 0) - { - spdata->hole = spdata->top; - MIWIDEARCSETUP(inx, iny, dy, inslw, ine, inxk, inxm, inyk, inym); - } - else - { - spdata->hole = FALSE; - doinner = -y; - } - spdata->count1 = -doinner - spdata->top; - spdata->count2 = y + doinner; - span = spdata->spans; - while (y) - { - MIFILLARCSTEP(slw); - span->lx = dy - x; - if (++doinner <= 0) - { - span->lw = slw; - span->rx = 0; - span->rw = span->lx + slw; - } - else - { - MIFILLINARCSTEP(inslw); - span->lw = x - inx; - span->rx = dy - inx + inslw; - span->rw = inx - x + slw - inslw; - } - span++; - } - if (spdata->bot) - { - if (spdata->count2) - spdata->count2--; - else - { - if (lw > (int)parc->height) - span[-1].rx = span[-1].rw = -((lw - (int)parc->height) >> 1); - else - span[-1].rw = 0; - spdata->count1--; - } - } -} - -static void -miComputeEllipseSpans( - int lw, - xArc *parc, - miArcSpanData *spdata) -{ - miArcSpan *span; - double w, h, r, xorg; - double Hs, Hf, WH, K, Vk, Nk, Fk, Vr, N, Nc, Z, rs; - double A, T, b, d, x, y, t, inx, outx = 0.0, hepp, hepm; - int flip, solution; - - w = (double)parc->width / 2.0; - h = (double)parc->height / 2.0; - r = lw / 2.0; - rs = r * r; - Hs = h * h; - WH = w * w - Hs; - Nk = w * r; - Vk = (Nk * Hs) / (WH + WH); - Hf = Hs * Hs; - Nk = (Hf - Nk * Nk) / WH; - Fk = Hf / WH; - hepp = h + EPSILON; - hepm = h - EPSILON; - K = h + ((lw - 1) >> 1); - span = spdata->spans; - if (parc->width & 1) - xorg = .5; - else - xorg = 0.0; - if (spdata->top) - { - span->lx = 0; - span->lw = 1; - span++; - } - spdata->count1 = 0; - spdata->count2 = 0; - spdata->hole = (spdata->top && - (int)parc->height * lw <= (int)(parc->width * parc->width) && - lw < (int)parc->height); - for (; K > 0.0; K -= 1.0) - { - N = (K * K + Nk) / 6.0; - Nc = N * N * N; - Vr = Vk * K; - t = Nc + Vr * Vr; - d = Nc + t; - if (d < 0.0) { - d = Nc; - b = N; - if ( (b < 0.0) == (t < 0.0) ) - { - b = -b; - d = -d; - } - Z = N - 2.0 * b * cos(acos(-t / d) / 3.0); - if ( (Z < 0.0) == (Vr < 0.0) ) - flip = 2; - else - flip = 1; - } - else - { - d = Vr * sqrt(d); - Z = N + cbrt(t + d) + cbrt(t - d); - flip = 0; - } - A = sqrt((Z + Z) - Nk); - T = (Fk - Z) * K / A; - inx = 0.0; - solution = FALSE; - b = -A + K; - d = b * b - 4 * (Z + T); - if (d >= 0) - { - d = sqrt(d); - y = (b + d) / 2; - if ((y >= 0.0) && (y < hepp)) - { - solution = TRUE; - if (y > hepm) - y = h; - t = y / h; - x = w * sqrt(1 - (t * t)); - t = K - y; - if (rs - (t * t) >= 0) - t = sqrt(rs - (t * t)); - else - t = 0; - if (flip == 2) - inx = x - t; - else - outx = x + t; - } - } - b = A + K; - d = b * b - 4 * (Z - T); - /* Because of the large magnitudes involved, we lose enough precision - * that sometimes we end up with a negative value near the axis, when - * it should be positive. This is a workaround. - */ - if (d < 0 && !solution) - d = 0.0; - if (d >= 0) { - d = sqrt(d); - y = (b + d) / 2; - if (y < hepp) - { - if (y > hepm) - y = h; - t = y / h; - x = w * sqrt(1 - (t * t)); - t = K - y; - if (rs - (t * t) >= 0) - inx = x - sqrt(rs - (t * t)); - else - inx = x; - } - y = (b - d) / 2; - if (y >= 0.0) - { - if (y > hepm) - y = h; - t = y / h; - x = w * sqrt(1 - (t * t)); - t = K - y; - if (rs - (t * t) >= 0) - t = sqrt(rs - (t * t)); - else - t = 0; - if (flip == 1) - inx = x - t; - else - outx = x + t; - } - } - span->lx = ICEIL(xorg - outx); - if (inx <= 0.0) - { - spdata->count1++; - span->lw = ICEIL(xorg + outx) - span->lx; - span->rx = ICEIL(xorg + inx); - span->rw = -ICEIL(xorg - inx); - } - else - { - spdata->count2++; - span->lw = ICEIL(xorg - inx) - span->lx; - span->rx = ICEIL(xorg + inx); - span->rw = ICEIL(xorg + outx) - span->rx; - } - span++; - } - if (spdata->bot) - { - outx = w + r; - if (r >= h && r <= w) - inx = 0.0; - else if (Nk < 0.0 && -Nk < Hs) - { - inx = w * sqrt(1 + Nk / Hs) - sqrt(rs + Nk); - if (inx > w - r) - inx = w - r; - } - else - inx = w - r; - span->lx = ICEIL(xorg - outx); - if (inx <= 0.0) - { - span->lw = ICEIL(xorg + outx) - span->lx; - span->rx = ICEIL(xorg + inx); - span->rw = -ICEIL(xorg - inx); - } - else - { - span->lw = ICEIL(xorg - inx) - span->lx; - span->rx = ICEIL(xorg + inx); - span->rw = ICEIL(xorg + outx) - span->rx; - } - } - if (spdata->hole) - { - span = &spdata->spans[spdata->count1]; - span->lw = -span->lx; - span->rx = 1; - span->rw = span->lw; - spdata->count1--; - spdata->count2++; - } -} - -static double -tailX( - double K, - struct arc_def *def, - struct arc_bound *bounds, - struct accelerators *acc) -{ - double w, h, r; - double Hs, Hf, WH, Vk, Nk, Fk, Vr, N, Nc, Z, rs; - double A, T, b, d, x, y, t, hepp, hepm; - int flip, solution; - double xs[2]; - double *xp; - - w = def->w; - h = def->h; - r = def->l; - rs = r * r; - Hs = acc->h2; - WH = -acc->h2mw2; - Nk = def->w * r; - Vk = (Nk * Hs) / (WH + WH); - Hf = acc->h4; - Nk = (Hf - Nk * Nk) / WH; - if (K == 0.0) { - if (Nk < 0.0 && -Nk < Hs) { - xs[0] = w * sqrt(1 + Nk / Hs) - sqrt(rs + Nk); - xs[1] = w - r; - if (acc->left.valid && boundedLe(K, bounds->left) && - !boundedLe(K, bounds->outer) && xs[0] >= 0.0 && xs[1] >= 0.0) - return xs[1]; - if (acc->right.valid && boundedLe(K, bounds->right) && - !boundedLe(K, bounds->inner) && xs[0] <= 0.0 && xs[1] <= 0.0) - return xs[1]; - return xs[0]; - } - return w - r; - } - Fk = Hf / WH; - hepp = h + EPSILON; - hepm = h - EPSILON; - N = (K * K + Nk) / 6.0; - Nc = N * N * N; - Vr = Vk * K; - xp = xs; - xs[0] = 0.0; - t = Nc + Vr * Vr; - d = Nc + t; - if (d < 0.0) { - d = Nc; - b = N; - if ( (b < 0.0) == (t < 0.0) ) - { - b = -b; - d = -d; - } - Z = N - 2.0 * b * cos(acos(-t / d) / 3.0); - if ( (Z < 0.0) == (Vr < 0.0) ) - flip = 2; - else - flip = 1; - } - else - { - d = Vr * sqrt(d); - Z = N + cbrt(t + d) + cbrt(t - d); - flip = 0; - } - A = sqrt((Z + Z) - Nk); - T = (Fk - Z) * K / A; - solution = FALSE; - b = -A + K; - d = b * b - 4 * (Z + T); - if (d >= 0 && flip == 2) - { - d = sqrt(d); - y = (b + d) / 2; - if ((y >= 0.0) && (y < hepp)) - { - solution = TRUE; - if (y > hepm) - y = h; - t = y / h; - x = w * sqrt(1 - (t * t)); - t = K - y; - if (rs - (t * t) >= 0) - t = sqrt(rs - (t * t)); - else - t = 0; - *xp++ = x - t; - } - } - b = A + K; - d = b * b - 4 * (Z - T); - /* Because of the large magnitudes involved, we lose enough precision - * that sometimes we end up with a negative value near the axis, when - * it should be positive. This is a workaround. - */ - if (d < 0 && !solution) - d = 0.0; - if (d >= 0) { - d = sqrt(d); - y = (b + d) / 2; - if (y < hepp) - { - if (y > hepm) - y = h; - t = y / h; - x = w * sqrt(1 - (t * t)); - t = K - y; - if (rs - (t * t) >= 0) - *xp++ = x - sqrt(rs - (t * t)); - else - *xp++ = x; - } - y = (b - d) / 2; - if (y >= 0.0 && flip == 1) - { - if (y > hepm) - y = h; - t = y / h; - x = w * sqrt(1 - (t * t)); - t = K - y; - if (rs - (t * t) >= 0) - t = sqrt(rs - (t * t)); - else - t = 0; - *xp++ = x - t; - } - } - if (xp > &xs[1]) { - if (acc->left.valid && boundedLe(K, bounds->left) && - !boundedLe(K, bounds->outer) && xs[0] >= 0.0 && xs[1] >= 0.0) - return xs[1]; - if (acc->right.valid && boundedLe(K, bounds->right) && - !boundedLe(K, bounds->inner) && xs[0] <= 0.0 && xs[1] <= 0.0) - return xs[1]; - } - return xs[0]; -} - -static miArcSpanData * -miComputeWideEllipse( - int lw, - xArc *parc, - Bool *mustFree) -{ - miArcSpanData *spdata; - arcCacheRec *cent, *lruent; - int k; - arcCacheRec fakeent; - - if (!lw) - lw = 1; - if (parc->height <= 1500) - { - *mustFree = FALSE; - cent = lastCacheHit; - if (cent->lw == lw && - cent->width == parc->width && cent->height == parc->height) - { - cent->lrustamp = ++lrustamp; - return cent->spdata; - } - lruent = &arcCache[0]; - for (k = CACHESIZE, cent = lruent; --k >= 0; cent++) - { - if (cent->lw == lw && - cent->width == parc->width && cent->height == parc->height) - { - cent->lrustamp = ++lrustamp; - lastCacheHit = cent; - return cent->spdata; - } - if (cent->lrustamp < lruent->lrustamp) - lruent = cent; - } - if (!cacheType) - { - cacheType = CreateNewResourceType(miFreeArcCache, "miArcCache"); - (void) AddResource(FakeClientID(0), cacheType, NULL); - } - } else { - lruent = &fakeent; - lruent->spdata = NULL; - *mustFree = TRUE; - } - k = (parc->height >> 1) + ((lw - 1) >> 1); - spdata = lruent->spdata; - if (!spdata || spdata->k != k) - { - if (spdata) - xfree(spdata); - spdata = xalloc(sizeof(miArcSpanData) + sizeof(miArcSpan) * (k + 2)); - lruent->spdata = spdata; - if (!spdata) - { - lruent->lrustamp = 0; - lruent->lw = 0; - return spdata; - } - spdata->spans = (miArcSpan *)(spdata + 1); - spdata->k = k; - } - spdata->top = !(lw & 1) && !(parc->width & 1); - spdata->bot = !(parc->height & 1); - lruent->lrustamp = ++lrustamp; - lruent->lw = lw; - lruent->width = parc->width; - lruent->height = parc->height; - if (lruent != &fakeent) - lastCacheHit = lruent; - if (parc->width == parc->height) - miComputeCircleSpans(lw, parc, spdata); - else - miComputeEllipseSpans(lw, parc, spdata); - return spdata; -} - -static void -miFillWideEllipse( - DrawablePtr pDraw, - GCPtr pGC, - xArc *parc) -{ - DDXPointPtr points; - DDXPointPtr pts; - int *widths; - int *wids; - miArcSpanData *spdata; - Bool mustFree; - miArcSpan *span; - int xorg, yorgu, yorgl; - int n; - - yorgu = parc->height + pGC->lineWidth; - n = (sizeof(int) * 2) * yorgu; - widths = xalloc(n + (sizeof(DDXPointRec) * 2) * yorgu); - if (!widths) - return; - points = (DDXPointPtr)((char *)widths + n); - spdata = miComputeWideEllipse((int)pGC->lineWidth, parc, &mustFree); - if (!spdata) - { - xfree(widths); - return; - } - pts = points; - wids = widths; - span = spdata->spans; - xorg = parc->x + (parc->width >> 1); - yorgu = parc->y + (parc->height >> 1); - yorgl = yorgu + (parc->height & 1); - if (pGC->miTranslate) - { - xorg += pDraw->x; - yorgu += pDraw->y; - yorgl += pDraw->y; - } - yorgu -= spdata->k; - yorgl += spdata->k; - if (spdata->top) - { - pts->x = xorg; - pts->y = yorgu - 1; - pts++; - *wids++ = 1; - span++; - } - for (n = spdata->count1; --n >= 0; ) - { - pts[0].x = xorg + span->lx; - pts[0].y = yorgu; - wids[0] = span->lw; - pts[1].x = pts[0].x; - pts[1].y = yorgl; - wids[1] = wids[0]; - yorgu++; - yorgl--; - pts += 2; - wids += 2; - span++; - } - if (spdata->hole) - { - pts[0].x = xorg; - pts[0].y = yorgl; - wids[0] = 1; - pts++; - wids++; - } - for (n = spdata->count2; --n >= 0; ) - { - pts[0].x = xorg + span->lx; - pts[0].y = yorgu; - wids[0] = span->lw; - pts[1].x = xorg + span->rx; - pts[1].y = pts[0].y; - wids[1] = span->rw; - pts[2].x = pts[0].x; - pts[2].y = yorgl; - wids[2] = wids[0]; - pts[3].x = pts[1].x; - pts[3].y = pts[2].y; - wids[3] = wids[1]; - yorgu++; - yorgl--; - pts += 4; - wids += 4; - span++; - } - if (spdata->bot) - { - if (span->rw <= 0) - { - pts[0].x = xorg + span->lx; - pts[0].y = yorgu; - wids[0] = span->lw; - pts++; - wids++; - } - else - { - pts[0].x = xorg + span->lx; - pts[0].y = yorgu; - wids[0] = span->lw; - pts[1].x = xorg + span->rx; - pts[1].y = pts[0].y; - wids[1] = span->rw; - pts += 2; - wids += 2; - } - } - if (mustFree) - xfree(spdata); - (*pGC->ops->FillSpans)(pDraw, pGC, pts - points, points, widths, FALSE); - - xfree(widths); -} - -/* - * miPolyArc strategy: - * - * If arc is zero width and solid, we don't have to worry about the rasterop - * or join styles. For wide solid circles, we use a fast integer algorithm. - * For wide solid ellipses, we use special case floating point code. - * Otherwise, we set up pDrawTo and pGCTo according to the rasterop, then - * draw using pGCTo and pDrawTo. If the raster-op was "tricky," that is, - * if it involves the destination, then we use PushPixels to move the bits - * from the scratch drawable to pDraw. (See the wide line code for a - * fuller explanation of this.) - */ - -void -miPolyArc(DrawablePtr pDraw, GCPtr pGC, int narcs, xArc *parcs) -{ - int i; - xArc *parc; - int xMin, xMax, yMin, yMax; - int pixmapWidth = 0, pixmapHeight = 0; - int xOrg = 0, yOrg = 0; - int width; - Bool fTricky; - DrawablePtr pDrawTo; - CARD32 fg, bg; - GCPtr pGCTo; - miPolyArcPtr polyArcs; - int cap[2], join[2]; - int iphase; - int halfWidth; - - width = pGC->lineWidth; - if(width == 0 && pGC->lineStyle == LineSolid) - { - for(i = narcs, parc = parcs; --i >= 0; parc++) - miArcSegment( pDraw, pGC, *parc, - (miArcFacePtr) 0, (miArcFacePtr) 0 ); - fillSpans (pDraw, pGC); - } - else - { - if ((pGC->lineStyle == LineSolid) && narcs) - { - while (parcs->width && parcs->height && - (parcs->angle2 >= FULLCIRCLE || - parcs->angle2 <= -FULLCIRCLE)) - { - miFillWideEllipse(pDraw, pGC, parcs); - if (!--narcs) - return; - parcs++; - } - } - - /* Set up pDrawTo and pGCTo based on the rasterop */ - switch(pGC->alu) - { - case GXclear: /* 0 */ - case GXcopy: /* src */ - case GXcopyInverted: /* NOT src */ - case GXset: /* 1 */ - fTricky = FALSE; - pDrawTo = pDraw; - pGCTo = pGC; - break; - default: - fTricky = TRUE; - - /* find bounding box around arcs */ - xMin = yMin = MAXSHORT; - xMax = yMax = MINSHORT; - - for(i = narcs, parc = parcs; --i >= 0; parc++) - { - xMin = min (xMin, parc->x); - yMin = min (yMin, parc->y); - xMax = max (xMax, (parc->x + (int) parc->width)); - yMax = max (yMax, (parc->y + (int) parc->height)); - } - - /* expand box to deal with line widths */ - halfWidth = (width + 1)/2; - xMin -= halfWidth; - yMin -= halfWidth; - xMax += halfWidth; - yMax += halfWidth; - - /* compute pixmap size; limit it to size of drawable */ - xOrg = max(xMin, 0); - yOrg = max(yMin, 0); - pixmapWidth = min(xMax, pDraw->width) - xOrg; - pixmapHeight = min(yMax, pDraw->height) - yOrg; - - /* if nothing left, return */ - if ( (pixmapWidth <= 0) || (pixmapHeight <= 0) ) return; - - for(i = narcs, parc = parcs; --i >= 0; parc++) - { - parc->x -= xOrg; - parc->y -= yOrg; - } - if (pGC->miTranslate) - { - xOrg += pDraw->x; - yOrg += pDraw->y; - } - - /* set up scratch GC */ - - pGCTo = GetScratchGC(1, pDraw->pScreen); - if (!pGCTo) - return; - gcvals[GCValsFunction] = GXcopy; - gcvals[GCValsForeground] = 1; - gcvals[GCValsBackground] = 0; - gcvals[GCValsLineWidth] = pGC->lineWidth; - gcvals[GCValsCapStyle] = pGC->capStyle; - gcvals[GCValsJoinStyle] = pGC->joinStyle; - dixChangeGC(NullClient, pGCTo, GCValsMask, gcvals, NULL); - - /* allocate a 1 bit deep pixmap of the appropriate size, and - * validate it */ - pDrawTo = (DrawablePtr)(*pDraw->pScreen->CreatePixmap) - (pDraw->pScreen, pixmapWidth, pixmapHeight, 1, - CREATE_PIXMAP_USAGE_SCRATCH); - if (!pDrawTo) - { - FreeScratchGC(pGCTo); - return; - } - ValidateGC(pDrawTo, pGCTo); - miClearDrawable(pDrawTo, pGCTo); - } - - fg = pGC->fgPixel; - bg = pGC->bgPixel; - if ((pGC->fillStyle == FillTiled) || - (pGC->fillStyle == FillOpaqueStippled)) - bg = fg; /* the protocol sez these don't cause color changes */ - - polyArcs = miComputeArcs (parcs, narcs, pGC); - - if (!polyArcs) - { - if (fTricky) { - (*pDraw->pScreen->DestroyPixmap) ((PixmapPtr)pDrawTo); - FreeScratchGC (pGCTo); - } - return; - } - - cap[0] = cap[1] = 0; - join[0] = join[1] = 0; - for (iphase = ((pGC->lineStyle == LineDoubleDash) ? 1 : 0); - iphase >= 0; - iphase--) - { - if (iphase == 1) { - dixChangeGC (NullClient, pGC, GCForeground, &bg, NULL); - ValidateGC (pDraw, pGC); - } else if (pGC->lineStyle == LineDoubleDash) { - dixChangeGC (NullClient, pGC, GCForeground, &fg, NULL); - ValidateGC (pDraw, pGC); - } - for (i = 0; i < polyArcs[iphase].narcs; i++) { - miArcDataPtr arcData; - - arcData = &polyArcs[iphase].arcs[i]; - miArcSegment(pDrawTo, pGCTo, arcData->arc, - &arcData->bounds[RIGHT_END], - &arcData->bounds[LEFT_END]); - if (polyArcs[iphase].arcs[i].render) { - fillSpans (pDrawTo, pGCTo); - /* - * don't cap self-joining arcs - */ - if (polyArcs[iphase].arcs[i].selfJoin && - cap[iphase] < polyArcs[iphase].arcs[i].cap) - cap[iphase]++; - while (cap[iphase] < polyArcs[iphase].arcs[i].cap) { - int arcIndex, end; - miArcDataPtr arcData0; - - arcIndex = polyArcs[iphase].caps[cap[iphase]].arcIndex; - end = polyArcs[iphase].caps[cap[iphase]].end; - arcData0 = &polyArcs[iphase].arcs[arcIndex]; - miArcCap (pDrawTo, pGCTo, - &arcData0->bounds[end], end, - arcData0->arc.x, arcData0->arc.y, - (double) arcData0->arc.width / 2.0, - (double) arcData0->arc.height / 2.0); - ++cap[iphase]; - } - while (join[iphase] < polyArcs[iphase].arcs[i].join) { - int arcIndex0, arcIndex1, end0, end1; - int phase0, phase1; - miArcDataPtr arcData0, arcData1; - miArcJoinPtr joinp; - - joinp = &polyArcs[iphase].joins[join[iphase]]; - arcIndex0 = joinp->arcIndex0; - end0 = joinp->end0; - arcIndex1 = joinp->arcIndex1; - end1 = joinp->end1; - phase0 = joinp->phase0; - phase1 = joinp->phase1; - arcData0 = &polyArcs[phase0].arcs[arcIndex0]; - arcData1 = &polyArcs[phase1].arcs[arcIndex1]; - miArcJoin (pDrawTo, pGCTo, - &arcData0->bounds[end0], - &arcData1->bounds[end1], - arcData0->arc.x, arcData0->arc.y, - (double) arcData0->arc.width / 2.0, - (double) arcData0->arc.height / 2.0, - arcData1->arc.x, arcData1->arc.y, - (double) arcData1->arc.width / 2.0, - (double) arcData1->arc.height / 2.0); - ++join[iphase]; - } - if (fTricky) { - if (pGC->serialNumber != pDraw->serialNumber) - ValidateGC (pDraw, pGC); - (*pGC->ops->PushPixels) (pGC, (PixmapPtr)pDrawTo, - pDraw, pixmapWidth, pixmapHeight, xOrg, yOrg); - miClearDrawable ((DrawablePtr) pDrawTo, pGCTo); - } - } - } - } - miFreeArcs(polyArcs, pGC); - - if(fTricky) - { - (*pGCTo->pScreen->DestroyPixmap)((PixmapPtr)pDrawTo); - FreeScratchGC(pGCTo); - } - } -} - -static double -angleBetween (SppPointRec center, SppPointRec point1, SppPointRec point2) -{ - double a1, a2, a; - - /* - * reflect from X coordinates back to ellipse - * coordinates -- y increasing upwards - */ - a1 = miDatan2 (- (point1.y - center.y), point1.x - center.x); - a2 = miDatan2 (- (point2.y - center.y), point2.x - center.x); - a = a2 - a1; - if (a <= -180.0) - a += 360.0; - else if (a > 180.0) - a -= 360.0; - return a; -} - -static void -translateBounds ( - miArcFacePtr b, - int x, - int y, - double fx, - double fy) -{ - fx += x; - fy += y; - b->clock.x -= fx; - b->clock.y -= fy; - b->center.x -= fx; - b->center.y -= fy; - b->counterClock.x -= fx; - b->counterClock.y -= fy; -} - -static void -miArcJoin(DrawablePtr pDraw, GCPtr pGC, miArcFacePtr pLeft, - miArcFacePtr pRight, int xOrgLeft, int yOrgLeft, - double xFtransLeft, double yFtransLeft, - int xOrgRight, int yOrgRight, - double xFtransRight, double yFtransRight) -{ - SppPointRec center, corner, otherCorner; - SppPointRec poly[5], e; - SppPointPtr pArcPts; - int cpt; - SppArcRec arc; - miArcFaceRec Right, Left; - int polyLen = 0; - int xOrg, yOrg; - double xFtrans, yFtrans; - double a; - double ae, ac2, ec2, bc2, de; - double width; - - xOrg = (xOrgRight + xOrgLeft) / 2; - yOrg = (yOrgRight + yOrgLeft) / 2; - xFtrans = (xFtransLeft + xFtransRight) / 2; - yFtrans = (yFtransLeft + yFtransRight) / 2; - Right = *pRight; - translateBounds (&Right, xOrg - xOrgRight, yOrg - yOrgRight, - xFtrans - xFtransRight, yFtrans - yFtransRight); - Left = *pLeft; - translateBounds (&Left, xOrg - xOrgLeft, yOrg - yOrgLeft, - xFtrans - xFtransLeft, yFtrans - yFtransLeft); - pRight = &Right; - pLeft = &Left; - - if (pRight->clock.x == pLeft->counterClock.x && - pRight->clock.y == pLeft->counterClock.y) - return; - center = pRight->center; - if (0 <= (a = angleBetween (center, pRight->clock, pLeft->counterClock)) - && a <= 180.0) - { - corner = pRight->clock; - otherCorner = pLeft->counterClock; - } else { - a = angleBetween (center, pLeft->clock, pRight->counterClock); - corner = pLeft->clock; - otherCorner = pRight->counterClock; - } - switch (pGC->joinStyle) { - case JoinRound: - width = (pGC->lineWidth ? (double)pGC->lineWidth : (double)1); - - arc.x = center.x - width/2; - arc.y = center.y - width/2; - arc.width = width; - arc.height = width; - arc.angle1 = -miDatan2 (corner.y - center.y, corner.x - center.x); - arc.angle2 = a; - pArcPts = xalloc (3 * sizeof (SppPointRec)); - if (!pArcPts) - return; - pArcPts[0].x = otherCorner.x; - pArcPts[0].y = otherCorner.y; - pArcPts[1].x = center.x; - pArcPts[1].y = center.y; - pArcPts[2].x = corner.x; - pArcPts[2].y = corner.y; - if( (cpt = miGetArcPts(&arc, 3, &pArcPts)) ) - { - /* by drawing with miFillSppPoly and setting the endpoints of the arc - * to be the corners, we assure that the cap will meet up with the - * rest of the line */ - miFillSppPoly(pDraw, pGC, cpt, pArcPts, xOrg, yOrg, xFtrans, yFtrans); - } - xfree(pArcPts); - return; - case JoinMiter: - /* - * don't miter arcs with less than 11 degrees between them - */ - if (a < 169.0) { - poly[0] = corner; - poly[1] = center; - poly[2] = otherCorner; - bc2 = (corner.x - otherCorner.x) * (corner.x - otherCorner.x) + - (corner.y - otherCorner.y) * (corner.y - otherCorner.y); - ec2 = bc2 / 4; - ac2 = (corner.x - center.x) * (corner.x - center.x) + - (corner.y - center.y) * (corner.y - center.y); - ae = sqrt (ac2 - ec2); - de = ec2 / ae; - e.x = (corner.x + otherCorner.x) / 2; - e.y = (corner.y + otherCorner.y) / 2; - poly[3].x = e.x + de * (e.x - center.x) / ae; - poly[3].y = e.y + de * (e.y - center.y) / ae; - poly[4] = corner; - polyLen = 5; - break; - } - case JoinBevel: - poly[0] = corner; - poly[1] = center; - poly[2] = otherCorner; - poly[3] = corner; - polyLen = 4; - break; - } - miFillSppPoly (pDraw, pGC, polyLen, poly, xOrg, yOrg, xFtrans, yFtrans); -} - -/*ARGSUSED*/ -static void -miArcCap ( - DrawablePtr pDraw, - GCPtr pGC, - miArcFacePtr pFace, - int end, - int xOrg, - int yOrg, - double xFtrans, - double yFtrans) -{ - SppPointRec corner, otherCorner, center, endPoint, poly[5]; - - corner = pFace->clock; - otherCorner = pFace->counterClock; - center = pFace->center; - switch (pGC->capStyle) { - case CapProjecting: - poly[0].x = otherCorner.x; - poly[0].y = otherCorner.y; - poly[1].x = corner.x; - poly[1].y = corner.y; - poly[2].x = corner.x - - (center.y - corner.y); - poly[2].y = corner.y + - (center.x - corner.x); - poly[3].x = otherCorner.x - - (otherCorner.y - center.y); - poly[3].y = otherCorner.y + - (otherCorner.x - center.x); - poly[4].x = otherCorner.x; - poly[4].y = otherCorner.y; - miFillSppPoly (pDraw, pGC, 5, poly, xOrg, yOrg, xFtrans, yFtrans); - break; - case CapRound: - /* - * miRoundCap just needs these to be unequal. - */ - endPoint = center; - endPoint.x = endPoint.x + 100; - miRoundCap (pDraw, pGC, center, endPoint, corner, otherCorner, 0, - -xOrg, -yOrg, xFtrans, yFtrans); - break; - } -} - -/* MIROUNDCAP -- a private helper function - * Put Rounded cap on end. pCenter is the center of this end of the line - * pEnd is the center of the other end of the line. pCorner is one of the - * two corners at this end of the line. - * NOTE: pOtherCorner must be counter-clockwise from pCorner. - */ -/*ARGSUSED*/ -static void -miRoundCap( - DrawablePtr pDraw, - GCPtr pGC, - SppPointRec pCenter, - SppPointRec pEnd, - SppPointRec pCorner, - SppPointRec pOtherCorner, - int fLineEnd, - int xOrg, - int yOrg, - double xFtrans, - double yFtrans) -{ - int cpt; - double width; - SppArcRec arc; - SppPointPtr pArcPts; - - width = (pGC->lineWidth ? (double)pGC->lineWidth : (double)1); - - arc.x = pCenter.x - width/2; - arc.y = pCenter.y - width/2; - arc.width = width; - arc.height = width; - arc.angle1 = -miDatan2 (pCorner.y - pCenter.y, pCorner.x - pCenter.x); - if(PTISEQUAL(pCenter, pEnd)) - arc.angle2 = - 180.0; - else { - arc.angle2 = -miDatan2 (pOtherCorner.y - pCenter.y, pOtherCorner.x - pCenter.x) - arc.angle1; - if (arc.angle2 < 0) - arc.angle2 += 360.0; - } - pArcPts = (SppPointPtr) NULL; - if( (cpt = miGetArcPts(&arc, 0, &pArcPts)) ) - { - /* by drawing with miFillSppPoly and setting the endpoints of the arc - * to be the corners, we assure that the cap will meet up with the - * rest of the line */ - miFillSppPoly(pDraw, pGC, cpt, pArcPts, -xOrg, -yOrg, xFtrans, yFtrans); - } - xfree(pArcPts); -} - -/* - * To avoid inaccuracy at the cardinal points, use trig functions - * which are exact for those angles - */ - -#ifndef M_PI -#define M_PI 3.14159265358979323846 -#endif -#ifndef M_PI_2 -#define M_PI_2 1.57079632679489661923 -#endif - -# define Dsin(d) ((d) == 0.0 ? 0.0 : ((d) == 90.0 ? 1.0 : sin(d*M_PI/180.0))) -# define Dcos(d) ((d) == 0.0 ? 1.0 : ((d) == 90.0 ? 0.0 : cos(d*M_PI/180.0))) -# define mod(a,b) ((a) >= 0 ? (a) % (b) : (b) - (-a) % (b)) - -static double -miDcos (double a) -{ - int i; - - if (floor (a/90) == a/90) { - i = (int) (a/90.0); - switch (mod (i, 4)) { - case 0: return 1; - case 1: return 0; - case 2: return -1; - case 3: return 0; - } - } - return cos (a * M_PI / 180.0); -} - -static double -miDsin (double a) -{ - int i; - - if (floor (a/90) == a/90) { - i = (int) (a/90.0); - switch (mod (i, 4)) { - case 0: return 0; - case 1: return 1; - case 2: return 0; - case 3: return -1; - } - } - return sin (a * M_PI / 180.0); -} - -static double -miDasin (double v) -{ - if (v == 0) - return 0.0; - if (v == 1.0) - return 90.0; - if (v == -1.0) - return -90.0; - return asin(v) * (180.0 / M_PI); -} - -static double -miDatan2 (double dy, double dx) -{ - if (dy == 0) { - if (dx >= 0) - return 0.0; - return 180.0; - } else if (dx == 0) { - if (dy > 0) - return 90.0; - return -90.0; - } else if (Fabs (dy) == Fabs (dx)) { - if (dy > 0) { - if (dx > 0) - return 45.0; - return 135.0; - } else { - if (dx > 0) - return 315.0; - return 225.0; - } - } else { - return atan2 (dy, dx) * (180.0 / M_PI); - } -} - -/* MIGETARCPTS -- Converts an arc into a set of line segments -- a helper - * routine for filled arc and line (round cap) code. - * Returns the number of points in the arc. Note that it takes a pointer - * to a pointer to where it should put the points and an index (cpt). - * This procedure allocates the space necessary to fit the arc points. - * Sometimes it's convenient for those points to be at the end of an existing - * array. (For example, if we want to leave a spare point to make sectors - * instead of segments.) So we pass in the xalloc()ed chunk that contains the - * array and an index saying where we should start stashing the points. - * If there isn't an array already, we just pass in a null pointer and - * count on xrealloc() to handle the null pointer correctly. - */ -static int -miGetArcPts( - SppArcPtr parc, /* points to an arc */ - int cpt, /* number of points already in arc list */ - SppPointPtr *ppPts) /* pointer to pointer to arc-list -- modified */ -{ - double st, /* Start Theta, start angle */ - et, /* End Theta, offset from start theta */ - dt, /* Delta Theta, angle to sweep ellipse */ - cdt, /* Cos Delta Theta, actually 2 cos(dt) */ - x0, y0, /* the recurrence formula needs two points to start */ - x1, y1, - x2, y2, /* this will be the new point generated */ - xc, yc; /* the center point */ - int count, i; - SppPointPtr poly; - - /* The spec says that positive angles indicate counterclockwise motion. - * Given our coordinate system (with 0,0 in the upper left corner), - * the screen appears flipped in Y. The easiest fix is to negate the - * angles given */ - - st = - parc->angle1; - - et = - parc->angle2; - - /* Try to get a delta theta that is within 1/2 pixel. Then adjust it - * so that it divides evenly into the total. - * I'm just using cdt 'cause I'm lazy. - */ - cdt = parc->width; - if (parc->height > cdt) - cdt = parc->height; - cdt /= 2.0; - if(cdt <= 0) - return 0; - if (cdt < 1.0) - cdt = 1.0; - dt = miDasin ( 1.0 / cdt ); /* minimum step necessary */ - count = et/dt; - count = abs(count) + 1; - dt = et/count; - count++; - - cdt = 2 * miDcos(dt); - if (!(poly = (SppPointPtr) xrealloc((pointer)*ppPts, - (cpt + count) * sizeof(SppPointRec)))) - return(0); - *ppPts = poly; - - xc = parc->width/2.0; /* store half width and half height */ - yc = parc->height/2.0; - - x0 = xc * miDcos(st); - y0 = yc * miDsin(st); - x1 = xc * miDcos(st + dt); - y1 = yc * miDsin(st + dt); - xc += parc->x; /* by adding initial point, these become */ - yc += parc->y; /* the center point */ - - poly[cpt].x = (xc + x0); - poly[cpt].y = (yc + y0); - poly[cpt + 1].x = (xc + x1); - poly[cpt + 1].y = (yc + y1); - - for(i = 2; i < count; i++) - { - x2 = cdt * x1 - x0; - y2 = cdt * y1 - y0; - - poly[cpt + i].x = (xc + x2); - poly[cpt + i].y = (yc + y2); - - x0 = x1; y0 = y1; - x1 = x2; y1 = y2; - } - /* adjust the last point */ - if (abs(parc->angle2) >= 360.0) - poly[cpt +i -1] = poly[0]; - else { - poly[cpt +i -1].x = (miDcos(st + et) * parc->width/2.0 + xc); - poly[cpt +i -1].y = (miDsin(st + et) * parc->height/2.0 + yc); - } - - return(count); -} - -struct arcData { - double x0, y0, x1, y1; - int selfJoin; -}; - -# define ADD_REALLOC_STEP 20 - -static void -addCap ( - miArcCapPtr *capsp, - int *ncapsp, - int *sizep, - int end, - int arcIndex) -{ - int newsize; - miArcCapPtr cap; - - if (*ncapsp == *sizep) - { - newsize = *sizep + ADD_REALLOC_STEP; - cap = (miArcCapPtr) xrealloc (*capsp, - newsize * sizeof (**capsp)); - if (!cap) - return; - *sizep = newsize; - *capsp = cap; - } - cap = &(*capsp)[*ncapsp]; - cap->end = end; - cap->arcIndex = arcIndex; - ++*ncapsp; -} - -static void -addJoin ( - miArcJoinPtr *joinsp, - int *njoinsp, - int *sizep, - int end0, - int index0, - int phase0, - int end1, - int index1, - int phase1) -{ - int newsize; - miArcJoinPtr join; - - if (*njoinsp == *sizep) - { - newsize = *sizep + ADD_REALLOC_STEP; - join = (miArcJoinPtr) xrealloc (*joinsp, - newsize * sizeof (**joinsp)); - if (!join) - return; - *sizep = newsize; - *joinsp = join; - } - join = &(*joinsp)[*njoinsp]; - join->end0 = end0; - join->arcIndex0 = index0; - join->phase0 = phase0; - join->end1 = end1; - join->arcIndex1 = index1; - join->phase1 = phase1; - ++*njoinsp; -} - -static miArcDataPtr -addArc ( - miArcDataPtr *arcsp, - int *narcsp, - int *sizep, - xArc *xarc) -{ - int newsize; - miArcDataPtr arc; - - if (*narcsp == *sizep) - { - newsize = *sizep + ADD_REALLOC_STEP; - arc = (miArcDataPtr) xrealloc (*arcsp, - newsize * sizeof (**arcsp)); - if (!arc) - return NULL; - *sizep = newsize; - *arcsp = arc; - } - arc = &(*arcsp)[*narcsp]; - arc->arc = *xarc; - ++*narcsp; - return arc; -} - -static void -miFreeArcs( - miPolyArcPtr arcs, - GCPtr pGC) -{ - int iphase; - - for (iphase = ((pGC->lineStyle == LineDoubleDash) ? 1 : 0); - iphase >= 0; - iphase--) - { - if (arcs[iphase].narcs > 0) - xfree(arcs[iphase].arcs); - if (arcs[iphase].njoins > 0) - xfree(arcs[iphase].joins); - if (arcs[iphase].ncaps > 0) - xfree(arcs[iphase].caps); - } - xfree(arcs); -} - -/* - * map angles to radial distance. This only deals with the first quadrant - */ - -/* - * a polygonal approximation to the arc for computing arc lengths - */ - -# define DASH_MAP_SIZE 91 - -# define dashIndexToAngle(di) ((((double) (di)) * 90.0) / ((double) DASH_MAP_SIZE - 1)) -# define xAngleToDashIndex(xa) ((((long) (xa)) * (DASH_MAP_SIZE - 1)) / (90 * 64)) -# define dashIndexToXAngle(di) ((((long) (di)) * (90 * 64)) / (DASH_MAP_SIZE - 1)) -# define dashXAngleStep (((double) (90 * 64)) / ((double) (DASH_MAP_SIZE - 1))) - -typedef struct { - double map[DASH_MAP_SIZE]; -} dashMap; - -static int computeAngleFromPath(int startAngle, int endAngle, dashMap *map, - int *lenp, int backwards); - -static void -computeDashMap ( - xArc *arcp, - dashMap *map) -{ - int di; - double a, x, y, prevx = 0.0, prevy = 0.0, dist; - - for (di = 0; di < DASH_MAP_SIZE; di++) { - a = dashIndexToAngle (di); - x = ((double) arcp->width / 2.0) * miDcos (a); - y = ((double) arcp->height / 2.0) * miDsin (a); - if (di == 0) { - map->map[di] = 0.0; - } else { - dist = hypot (x - prevx, y - prevy); - map->map[di] = map->map[di - 1] + dist; - } - prevx = x; - prevy = y; - } -} - -typedef enum {HORIZONTAL, VERTICAL, OTHER} arcTypes; - -/* this routine is a bit gory */ - -static miPolyArcPtr -miComputeArcs ( - xArc *parcs, - int narcs, - GCPtr pGC) -{ - int isDashed, isDoubleDash; - int dashOffset; - miPolyArcPtr arcs; - int start, i, j, k = 0, nexti, nextk = 0; - int joinSize[2]; - int capSize[2]; - int arcSize[2]; - int angle2; - double a0, a1; - struct arcData *data; - miArcDataPtr arc; - xArc xarc; - int iphase, prevphase = 0, joinphase; - int arcsJoin; - int selfJoin; - - int iDash = 0, dashRemaining = 0; - int iDashStart = 0, dashRemainingStart = 0, iphaseStart; - int startAngle, spanAngle, endAngle, backwards = 0; - int prevDashAngle, dashAngle; - dashMap map; - - isDashed = !(pGC->lineStyle == LineSolid); - isDoubleDash = (pGC->lineStyle == LineDoubleDash); - dashOffset = pGC->dashOffset; - - data = xalloc (narcs * sizeof (struct arcData)); - if (!data) - return NULL; - arcs = xalloc (sizeof (*arcs) * (isDoubleDash ? 2 : 1)); - if (!arcs) - { - xfree(data); - return NULL; - } - for (i = 0; i < narcs; i++) { - a0 = todeg (parcs[i].angle1); - angle2 = parcs[i].angle2; - if (angle2 > FULLCIRCLE) - angle2 = FULLCIRCLE; - else if (angle2 < -FULLCIRCLE) - angle2 = -FULLCIRCLE; - data[i].selfJoin = angle2 == FULLCIRCLE || angle2 == -FULLCIRCLE; - a1 = todeg (parcs[i].angle1 + angle2); - data[i].x0 = parcs[i].x + (double) parcs[i].width / 2 * (1 + miDcos (a0)); - data[i].y0 = parcs[i].y + (double) parcs[i].height / 2 * (1 - miDsin (a0)); - data[i].x1 = parcs[i].x + (double) parcs[i].width / 2 * (1 + miDcos (a1)); - data[i].y1 = parcs[i].y + (double) parcs[i].height / 2 * (1 - miDsin (a1)); - } - - for (iphase = 0; iphase < (isDoubleDash ? 2 : 1); iphase++) { - arcs[iphase].njoins = 0; - arcs[iphase].joins = 0; - joinSize[iphase] = 0; - - arcs[iphase].ncaps = 0; - arcs[iphase].caps = 0; - capSize[iphase] = 0; - - arcs[iphase].narcs = 0; - arcs[iphase].arcs = 0; - arcSize[iphase] = 0; - } - - iphase = 0; - if (isDashed) { - iDash = 0; - dashRemaining = pGC->dash[0]; - while (dashOffset > 0) { - if (dashOffset >= dashRemaining) { - dashOffset -= dashRemaining; - iphase = iphase ? 0 : 1; - iDash++; - if (iDash == pGC->numInDashList) - iDash = 0; - dashRemaining = pGC->dash[iDash]; - } else { - dashRemaining -= dashOffset; - dashOffset = 0; - } - } - iDashStart = iDash; - dashRemainingStart = dashRemaining; - } - iphaseStart = iphase; - - for (i = narcs - 1; i >= 0; i--) { - j = i + 1; - if (j == narcs) - j = 0; - if (data[i].selfJoin || i == j || - (UNEQUAL (data[i].x1, data[j].x0) || - UNEQUAL (data[i].y1, data[j].y0))) - { - if (iphase == 0 || isDoubleDash) - addCap (&arcs[iphase].caps, &arcs[iphase].ncaps, - &capSize[iphase], RIGHT_END, 0); - break; - } - } - start = i + 1; - if (start == narcs) - start = 0; - i = start; - for (;;) { - j = i + 1; - if (j == narcs) - j = 0; - nexti = i+1; - if (nexti == narcs) - nexti = 0; - if (isDashed) { - /* - ** deal with dashed arcs. Use special rules for certain 0 area arcs. - ** Presumably, the other 0 area arcs still aren't done right. - */ - arcTypes arcType = OTHER; - CARD16 thisLength; - - if (parcs[i].height == 0 - && (parcs[i].angle1 % FULLCIRCLE) == 0x2d00 - && parcs[i].angle2 == 0x2d00) - arcType = HORIZONTAL; - else if (parcs[i].width == 0 - && (parcs[i].angle1 % FULLCIRCLE) == 0x1680 - && parcs[i].angle2 == 0x2d00) - arcType = VERTICAL; - if (arcType == OTHER) { - /* - * precompute an approximation map - */ - computeDashMap (&parcs[i], &map); - /* - * compute each individual dash segment using the path - * length function - */ - startAngle = parcs[i].angle1; - spanAngle = parcs[i].angle2; - if (spanAngle > FULLCIRCLE) - spanAngle = FULLCIRCLE; - else if (spanAngle < -FULLCIRCLE) - spanAngle = -FULLCIRCLE; - if (startAngle < 0) - startAngle = FULLCIRCLE - (-startAngle) % FULLCIRCLE; - if (startAngle >= FULLCIRCLE) - startAngle = startAngle % FULLCIRCLE; - endAngle = startAngle + spanAngle; - backwards = spanAngle < 0; - } else { - xarc = parcs[i]; - if (arcType == VERTICAL) { - xarc.angle1 = 0x1680; - startAngle = parcs[i].y; - endAngle = startAngle + parcs[i].height; - } else { - xarc.angle1 = 0x2d00; - startAngle = parcs[i].x; - endAngle = startAngle + parcs[i].width; - } - } - dashAngle = startAngle; - selfJoin = data[i].selfJoin && - (iphase == 0 || isDoubleDash); - /* - * add dashed arcs to each bucket - */ - arc = 0; - while (dashAngle != endAngle) { - prevDashAngle = dashAngle; - if (arcType == OTHER) { - dashAngle = computeAngleFromPath (prevDashAngle, endAngle, - &map, &dashRemaining, backwards); - /* avoid troubles with huge arcs and small dashes */ - if (dashAngle == prevDashAngle) { - if (backwards) - dashAngle--; - else - dashAngle++; - } - } else { - thisLength = (dashAngle + dashRemaining <= endAngle) ? - dashRemaining : endAngle - dashAngle; - if (arcType == VERTICAL) { - xarc.y = dashAngle; - xarc.height = thisLength; - } else { - xarc.x = dashAngle; - xarc.width = thisLength; - } - dashAngle += thisLength; - dashRemaining -= thisLength; - } - if (iphase == 0 || isDoubleDash) { - if (arcType == OTHER) { - xarc = parcs[i]; - spanAngle = prevDashAngle; - if (spanAngle < 0) - spanAngle = FULLCIRCLE - (-spanAngle) % FULLCIRCLE; - if (spanAngle >= FULLCIRCLE) - spanAngle = spanAngle % FULLCIRCLE; - xarc.angle1 = spanAngle; - spanAngle = dashAngle - prevDashAngle; - if (backwards) { - if (dashAngle > prevDashAngle) - spanAngle = - FULLCIRCLE + spanAngle; - } else { - if (dashAngle < prevDashAngle) - spanAngle = FULLCIRCLE + spanAngle; - } - if (spanAngle > FULLCIRCLE) - spanAngle = FULLCIRCLE; - if (spanAngle < -FULLCIRCLE) - spanAngle = -FULLCIRCLE; - xarc.angle2 = spanAngle; - } - arc = addArc (&arcs[iphase].arcs, &arcs[iphase].narcs, - &arcSize[iphase], &xarc); - if (!arc) - goto arcfail; - /* - * cap each end of an on/off dash - */ - if (!isDoubleDash) { - if (prevDashAngle != startAngle) { - addCap (&arcs[iphase].caps, - &arcs[iphase].ncaps, - &capSize[iphase], RIGHT_END, - arc - arcs[iphase].arcs); - - } - if (dashAngle != endAngle) { - addCap (&arcs[iphase].caps, - &arcs[iphase].ncaps, - &capSize[iphase], LEFT_END, - arc - arcs[iphase].arcs); - } - } - arc->cap = arcs[iphase].ncaps; - arc->join = arcs[iphase].njoins; - arc->render = 0; - arc->selfJoin = 0; - if (dashAngle == endAngle) - arc->selfJoin = selfJoin; - } - prevphase = iphase; - if (dashRemaining <= 0) { - ++iDash; - if (iDash == pGC->numInDashList) - iDash = 0; - iphase = iphase ? 0:1; - dashRemaining = pGC->dash[iDash]; - } - } - /* - * make sure a place exists for the position data when - * drawing a zero-length arc - */ - if (startAngle == endAngle) { - prevphase = iphase; - if (!isDoubleDash && iphase == 1) - prevphase = 0; - arc = addArc (&arcs[prevphase].arcs, &arcs[prevphase].narcs, - &arcSize[prevphase], &parcs[i]); - if (!arc) - goto arcfail; - arc->join = arcs[prevphase].njoins; - arc->cap = arcs[prevphase].ncaps; - arc->selfJoin = data[i].selfJoin; - } - } else { - arc = addArc (&arcs[iphase].arcs, &arcs[iphase].narcs, - &arcSize[iphase], &parcs[i]); - if (!arc) - goto arcfail; - arc->join = arcs[iphase].njoins; - arc->cap = arcs[iphase].ncaps; - arc->selfJoin = data[i].selfJoin; - prevphase = iphase; - } - if (prevphase == 0 || isDoubleDash) - k = arcs[prevphase].narcs - 1; - if (iphase == 0 || isDoubleDash) - nextk = arcs[iphase].narcs; - if (nexti == start) { - nextk = 0; - if (isDashed) { - iDash = iDashStart; - iphase = iphaseStart; - dashRemaining = dashRemainingStart; - } - } - arcsJoin = narcs > 1 && i != j && - ISEQUAL (data[i].x1, data[j].x0) && - ISEQUAL (data[i].y1, data[j].y0) && - !data[i].selfJoin && !data[j].selfJoin; - if (arc) - { - if (arcsJoin) - arc->render = 0; - else - arc->render = 1; - } - if (arcsJoin && - (prevphase == 0 || isDoubleDash) && - (iphase == 0 || isDoubleDash)) - { - joinphase = iphase; - if (isDoubleDash) { - if (nexti == start) - joinphase = iphaseStart; - /* - * if the join is right at the dash, - * draw the join in foreground - * This is because the foreground - * arcs are computed second, the results - * of which are needed to draw the join - */ - if (joinphase != prevphase) - joinphase = 0; - } - if (joinphase == 0 || isDoubleDash) { - addJoin (&arcs[joinphase].joins, - &arcs[joinphase].njoins, - &joinSize[joinphase], - LEFT_END, k, prevphase, - RIGHT_END, nextk, iphase); - arc->join = arcs[prevphase].njoins; - } - } else { - /* - * cap the left end of this arc - * unless it joins itself - */ - if ((prevphase == 0 || isDoubleDash) && - !arc->selfJoin) - { - addCap (&arcs[prevphase].caps, &arcs[prevphase].ncaps, - &capSize[prevphase], LEFT_END, k); - arc->cap = arcs[prevphase].ncaps; - } - if (isDashed && !arcsJoin) { - iDash = iDashStart; - iphase = iphaseStart; - dashRemaining = dashRemainingStart; - } - nextk = arcs[iphase].narcs; - if (nexti == start) { - nextk = 0; - iDash = iDashStart; - iphase = iphaseStart; - dashRemaining = dashRemainingStart; - } - /* - * cap the right end of the next arc. If the - * next arc is actually the first arc, only - * cap it if it joins with this arc. This - * case will occur when the final dash segment - * of an on/off dash is off. Of course, this - * cap will be drawn at a strange time, but that - * hardly matters... - */ - if ((iphase == 0 || isDoubleDash) && - (nexti != start || (arcsJoin && isDashed))) - addCap (&arcs[iphase].caps, &arcs[iphase].ncaps, - &capSize[iphase], RIGHT_END, nextk); - } - i = nexti; - if (i == start) - break; - } - /* - * make sure the last section is rendered - */ - for (iphase = 0; iphase < (isDoubleDash ? 2 : 1); iphase++) - if (arcs[iphase].narcs > 0) { - arcs[iphase].arcs[arcs[iphase].narcs-1].render = 1; - arcs[iphase].arcs[arcs[iphase].narcs-1].join = - arcs[iphase].njoins; - arcs[iphase].arcs[arcs[iphase].narcs-1].cap = - arcs[iphase].ncaps; - } - xfree(data); - return arcs; -arcfail: - miFreeArcs(arcs, pGC); - xfree(data); - return NULL; -} - -static double -angleToLength ( - int angle, - dashMap *map) -{ - double len, excesslen, sidelen = map->map[DASH_MAP_SIZE - 1], totallen; - int di; - int excess; - Bool oddSide = FALSE; - - totallen = 0; - if (angle >= 0) { - while (angle >= 90 * 64) { - angle -= 90 * 64; - totallen += sidelen; - oddSide = !oddSide; - } - } else { - while (angle < 0) { - angle += 90 * 64; - totallen -= sidelen; - oddSide = !oddSide; - } - } - if (oddSide) - angle = 90 * 64 - angle; - - di = xAngleToDashIndex (angle); - excess = angle - dashIndexToXAngle (di); - - len = map->map[di]; - /* - * linearly interpolate between this point and the next - */ - if (excess > 0) { - excesslen = (map->map[di + 1] - map->map[di]) * - ((double) excess) / dashXAngleStep; - len += excesslen; - } - if (oddSide) - totallen += (sidelen - len); - else - totallen += len; - return totallen; -} - -/* - * len is along the arc, but may be more than one rotation - */ - -static int -lengthToAngle ( - double len, - dashMap *map) -{ - double sidelen = map->map[DASH_MAP_SIZE - 1]; - int angle, angleexcess; - Bool oddSide = FALSE; - int a0, a1, a; - - angle = 0; - /* - * step around the ellipse, subtracting sidelens and - * adding 90 degrees. oddSide will tell if the - * map should be interpolated in reverse - */ - if (len >= 0) { - if (sidelen == 0) - return 2 * FULLCIRCLE; /* infinity */ - while (len >= sidelen) { - angle += 90 * 64; - len -= sidelen; - oddSide = !oddSide; - } - } else { - if (sidelen == 0) - return -2 * FULLCIRCLE; /* infinity */ - while (len < 0) { - angle -= 90 * 64; - len += sidelen; - oddSide = !oddSide; - } - } - if (oddSide) - len = sidelen - len; - a0 = 0; - a1 = DASH_MAP_SIZE - 1; - /* - * binary search for the closest pre-computed length - */ - while (a1 - a0 > 1) { - a = (a0 + a1) / 2; - if (len > map->map[a]) - a0 = a; - else - a1 = a; - } - angleexcess = dashIndexToXAngle (a0); - /* - * linearly interpolate to the next point - */ - angleexcess += (len - map->map[a0]) / - (map->map[a0+1] - map->map[a0]) * dashXAngleStep; - if (oddSide) - angle += (90 * 64) - angleexcess; - else - angle += angleexcess; - return angle; -} - -/* - * compute the angle of an ellipse which cooresponds to - * the given path length. Note that the correct solution - * to this problem is an eliptic integral, we'll punt and - * approximate (it's only for dashes anyway). This - * approximation uses a polygon. - * - * The remaining portion of len is stored in *lenp - - * this will be negative if the arc extends beyond - * len and positive if len extends beyond the arc. - */ - -static int -computeAngleFromPath ( - int startAngle, - int endAngle, /* normalized absolute angles in *64 degrees */ - dashMap *map, - int *lenp, - int backwards) -{ - int a0, a1, a; - double len0; - int len; - - a0 = startAngle; - a1 = endAngle; - len = *lenp; - if (backwards) { - /* - * flip the problem around to always be - * forwards - */ - a0 = FULLCIRCLE - a0; - a1 = FULLCIRCLE - a1; - } - if (a1 < a0) - a1 += FULLCIRCLE; - len0 = angleToLength (a0, map); - a = lengthToAngle (len0 + len, map); - if (a > a1) { - a = a1; - len -= angleToLength (a1, map) - len0; - } else - len = 0; - if (backwards) - a = FULLCIRCLE - a; - *lenp = len; - return a; -} - -/* - * scan convert wide arcs. - */ - -/* - * draw zero width/height arcs - */ - -static void -drawZeroArc ( - DrawablePtr pDraw, - GCPtr pGC, - xArc *tarc, - int lw, - miArcFacePtr left, - miArcFacePtr right) -{ - double x0 = 0.0, y0 = 0.0, x1 = 0.0, y1 = 0.0, w, h, x, y; - double xmax, ymax, xmin, ymin; - int a0, a1; - double a, startAngle, endAngle; - double l, lx, ly; - - l = lw / 2.0; - a0 = tarc->angle1; - a1 = tarc->angle2; - if (a1 > FULLCIRCLE) - a1 = FULLCIRCLE; - else if (a1 < -FULLCIRCLE) - a1 = -FULLCIRCLE; - w = (double)tarc->width / 2.0; - h = (double)tarc->height / 2.0; - /* - * play in X coordinates right away - */ - startAngle = - ((double) a0 / 64.0); - endAngle = - ((double) (a0 + a1) / 64.0); - - xmax = -w; - xmin = w; - ymax = -h; - ymin = h; - a = startAngle; - for (;;) - { - x = w * miDcos(a); - y = h * miDsin(a); - if (a == startAngle) - { - x0 = x; - y0 = y; - } - if (a == endAngle) - { - x1 = x; - y1 = y; - } - if (x > xmax) - xmax = x; - if (x < xmin) - xmin = x; - if (y > ymax) - ymax = y; - if (y < ymin) - ymin = y; - if (a == endAngle) - break; - if (a1 < 0) /* clockwise */ - { - if (floor (a / 90.0) == floor (endAngle / 90.0)) - a = endAngle; - else - a = 90 * (floor (a/90.0) + 1); - } - else - { - if (ceil (a / 90.0) == ceil (endAngle / 90.0)) - a = endAngle; - else - a = 90 * (ceil (a/90.0) - 1); - } - } - lx = ly = l; - if ((x1 - x0) + (y1 - y0) < 0) - lx = ly = -l; - if (h) - { - ly = 0.0; - lx = -lx; - } - else - lx = 0.0; - if (right) - { - right->center.x = x0; - right->center.y = y0; - right->clock.x = x0 - lx; - right->clock.y = y0 - ly; - right->counterClock.x = x0 + lx; - right->counterClock.y = y0 + ly; - } - if (left) - { - left->center.x = x1; - left->center.y = y1; - left->clock.x = x1 + lx; - left->clock.y = y1 + ly; - left->counterClock.x = x1 - lx; - left->counterClock.y = y1 - ly; - } - - x0 = xmin; - x1 = xmax; - y0 = ymin; - y1 = ymax; - if (ymin != y1) { - xmin = -l; - xmax = l; - } else { - ymin = -l; - ymax = l; - } - if (xmax != xmin && ymax != ymin) { - int minx, maxx, miny, maxy; - xRectangle rect; - - minx = ICEIL (xmin + w) + tarc->x; - maxx = ICEIL (xmax + w) + tarc->x; - miny = ICEIL (ymin + h) + tarc->y; - maxy = ICEIL (ymax + h) + tarc->y; - rect.x = minx; - rect.y = miny; - rect.width = maxx - minx; - rect.height = maxy - miny; - (*pGC->ops->PolyFillRect) (pDraw, pGC, 1, &rect); - } -} - -/* - * this computes the ellipse y value associated with the - * bottom of the tail. - */ - -static void -tailEllipseY ( - struct arc_def *def, - struct accelerators *acc) -{ - double t; - - acc->tail_y = 0.0; - if (def->w == def->h) - return; - t = def->l * def->w; - if (def->w > def->h) { - if (t < acc->h2) - return; - } else { - if (t > acc->h2) - return; - } - t = 2.0 * def->h * t; - t = (CUBED_ROOT_4 * acc->h2 - cbrt(t * t)) / acc->h2mw2; - if (t > 0.0) - acc->tail_y = def->h / CUBED_ROOT_2 * sqrt(t); -} - -/* - * inverse functions -- compute edge coordinates - * from the ellipse - */ - -static double -outerXfromXY ( - double x, - double y, - struct arc_def *def, - struct accelerators *acc) -{ - return x + (x * acc->h2l) / sqrt (x*x * acc->h4 + y*y * acc->w4); -} - -static double -outerYfromXY ( - double x, - double y, - struct arc_def *def, - struct accelerators *acc) -{ - return y + (y * acc->w2l) / sqrt (x*x * acc->h4 + y*y * acc->w4); -} - -static double -innerXfromXY ( - double x, - double y, - struct arc_def *def, - struct accelerators *acc) -{ - return x - (x * acc->h2l) / sqrt (x*x * acc->h4 + y*y * acc->w4); -} - -static double -innerYfromXY ( - double x, - double y, - struct arc_def *def, - struct accelerators *acc) -{ - return y - (y * acc->w2l) / sqrt (x*x * acc->h4 + y*y * acc->w4); -} - -static double -innerYfromY ( - double y, - struct arc_def *def, - struct accelerators *acc) -{ - double x; - - x = (def->w / def->h) * sqrt (acc->h2 - y*y); - - return y - (y * acc->w2l) / sqrt (x*x * acc->h4 + y*y * acc->w4); -} - -static void -computeLine ( - double x1, - double y1, - double x2, - double y2, - struct line *line) -{ - if (y1 == y2) - line->valid = 0; - else { - line->m = (x1 - x2) / (y1 - y2); - line->b = x1 - y1 * line->m; - line->valid = 1; - } -} - -/* - * compute various accelerators for an ellipse. These - * are simply values that are used repeatedly in - * the computations - */ - -static void -computeAcc ( - xArc *tarc, - int lw, - struct arc_def *def, - struct accelerators *acc) -{ - def->w = ((double) tarc->width) / 2.0; - def->h = ((double) tarc->height) / 2.0; - def->l = ((double) lw) / 2.0; - acc->h2 = def->h * def->h; - acc->w2 = def->w * def->w; - acc->h4 = acc->h2 * acc->h2; - acc->w4 = acc->w2 * acc->w2; - acc->h2l = acc->h2 * def->l; - acc->w2l = acc->w2 * def->l; - acc->h2mw2 = acc->h2 - acc->w2; - acc->fromIntX = (tarc->width & 1) ? 0.5 : 0.0; - acc->fromIntY = (tarc->height & 1) ? 0.5 : 0.0; - acc->xorg = tarc->x + (tarc->width >> 1); - acc->yorgu = tarc->y + (tarc->height >> 1); - acc->yorgl = acc->yorgu + (tarc->height & 1); - tailEllipseY (def, acc); -} - -/* - * compute y value bounds of various portions of the arc, - * the outer edge, the ellipse and the inner edge. - */ - -static void -computeBound ( - struct arc_def *def, - struct arc_bound *bound, - struct accelerators *acc, - miArcFacePtr right, - miArcFacePtr left) -{ - double t; - double innerTaily; - double tail_y; - struct bound innerx, outerx; - struct bound ellipsex; - - bound->ellipse.min = Dsin (def->a0) * def->h; - bound->ellipse.max = Dsin (def->a1) * def->h; - if (def->a0 == 45 && def->w == def->h) - ellipsex.min = bound->ellipse.min; - else - ellipsex.min = Dcos (def->a0) * def->w; - if (def->a1 == 45 && def->w == def->h) - ellipsex.max = bound->ellipse.max; - else - ellipsex.max = Dcos (def->a1) * def->w; - bound->outer.min = outerYfromXY (ellipsex.min, bound->ellipse.min, def, acc); - bound->outer.max = outerYfromXY (ellipsex.max, bound->ellipse.max, def, acc); - bound->inner.min = innerYfromXY (ellipsex.min, bound->ellipse.min, def, acc); - bound->inner.max = innerYfromXY (ellipsex.max, bound->ellipse.max, def, acc); - - outerx.min = outerXfromXY (ellipsex.min, bound->ellipse.min, def, acc); - outerx.max = outerXfromXY (ellipsex.max, bound->ellipse.max, def, acc); - innerx.min = innerXfromXY (ellipsex.min, bound->ellipse.min, def, acc); - innerx.max = innerXfromXY (ellipsex.max, bound->ellipse.max, def, acc); - - /* - * save the line end points for the - * cap code to use. Careful here, these are - * in cartesean coordinates (y increasing upwards) - * while the cap code uses inverted coordinates - * (y increasing downwards) - */ - - if (right) { - right->counterClock.y = bound->outer.min; - right->counterClock.x = outerx.min; - right->center.y = bound->ellipse.min; - right->center.x = ellipsex.min; - right->clock.y = bound->inner.min; - right->clock.x = innerx.min; - } - - if (left) { - left->clock.y = bound->outer.max; - left->clock.x = outerx.max; - left->center.y = bound->ellipse.max; - left->center.x = ellipsex.max; - left->counterClock.y = bound->inner.max; - left->counterClock.x = innerx.max; - } - - bound->left.min = bound->inner.max; - bound->left.max = bound->outer.max; - bound->right.min = bound->inner.min; - bound->right.max = bound->outer.min; - - computeLine (innerx.min, bound->inner.min, outerx.min, bound->outer.min, - &acc->right); - computeLine (innerx.max, bound->inner.max, outerx.max, bound->outer.max, - &acc->left); - - if (bound->inner.min > bound->inner.max) { - t = bound->inner.min; - bound->inner.min = bound->inner.max; - bound->inner.max = t; - } - tail_y = acc->tail_y; - if (tail_y > bound->ellipse.max) - tail_y = bound->ellipse.max; - else if (tail_y < bound->ellipse.min) - tail_y = bound->ellipse.min; - innerTaily = innerYfromY (tail_y, def, acc); - if (bound->inner.min > innerTaily) - bound->inner.min = innerTaily; - if (bound->inner.max < innerTaily) - bound->inner.max = innerTaily; - bound->inneri.min = ICEIL(bound->inner.min - acc->fromIntY); - bound->inneri.max = floor(bound->inner.max - acc->fromIntY); - bound->outeri.min = ICEIL(bound->outer.min - acc->fromIntY); - bound->outeri.max = floor(bound->outer.max - acc->fromIntY); -} - -/* - * this section computes the x value of the span at y - * intersected with the specified face of the ellipse. - * - * this is the min/max X value over the set of normal - * lines to the entire ellipse, the equation of the - * normal lines is: - * - * ellipse_x h^2 h^2 - * x = ------------ y + ellipse_x (1 - --- ) - * ellipse_y w^2 w^2 - * - * compute the derivative with-respect-to ellipse_y and solve - * for zero: - * - * (w^2 - h^2) ellipse_y^3 + h^4 y - * 0 = - ---------------------------------- - * h w ellipse_y^2 sqrt (h^2 - ellipse_y^2) - * - * ( h^4 y ) - * ellipse_y = ( ---------- ) ^ (1/3) - * ( (h^2 - w^2) ) - * - * The other two solutions to the equation are imaginary. - * - * This gives the position on the ellipse which generates - * the normal with the largest/smallest x intersection point. - * - * Now compute the second derivative to check whether - * the intersection is a minimum or maximum: - * - * h (y0^3 (w^2 - h^2) + h^2 y (3y0^2 - 2h^2)) - * - ------------------------------------------- - * w y0^3 (sqrt (h^2 - y^2)) ^ 3 - * - * as we only care about the sign, - * - * - (y0^3 (w^2 - h^2) + h^2 y (3y0^2 - 2h^2)) - * - * or (to use accelerators), - * - * y0^3 (h^2 - w^2) - h^2 y (3y0^2 - 2h^2) - * - */ - -/* - * computes the position on the ellipse whose normal line - * intersects the given scan line maximally - */ - -static double -hookEllipseY ( - double scan_y, - struct arc_bound *bound, - struct accelerators *acc, - int left) -{ - double ret; - - if (acc->h2mw2 == 0) { - if ( (scan_y > 0 && !left) || (scan_y < 0 && left) ) - return bound->ellipse.min; - return bound->ellipse.max; - } - ret = (acc->h4 * scan_y) / (acc->h2mw2); - if (ret >= 0) - return cbrt (ret); - else - return -cbrt (-ret); -} - -/* - * computes the X value of the intersection of the - * given scan line with the right side of the lower hook - */ - -static double -hookX ( - double scan_y, - struct arc_def *def, - struct arc_bound *bound, - struct accelerators *acc, - int left) -{ - double ellipse_y, x; - double maxMin; - - if (def->w != def->h) { - ellipse_y = hookEllipseY (scan_y, bound, acc, left); - if (boundedLe (ellipse_y, bound->ellipse)) { - /* - * compute the value of the second - * derivative - */ - maxMin = ellipse_y*ellipse_y*ellipse_y * acc->h2mw2 - - acc->h2 * scan_y * (3 * ellipse_y*ellipse_y - 2*acc->h2); - if ((left && maxMin > 0) || (!left && maxMin < 0)) { - if (ellipse_y == 0) - return def->w + left ? -def->l : def->l; - x = (acc->h2 * scan_y - ellipse_y * acc->h2mw2) * - sqrt (acc->h2 - ellipse_y * ellipse_y) / - (def->h * def->w * ellipse_y); - return x; - } - } - } - if (left) { - if (acc->left.valid && boundedLe (scan_y, bound->left)) { - x = intersectLine (scan_y, acc->left); - } else { - if (acc->right.valid) - x = intersectLine (scan_y, acc->right); - else - x = def->w - def->l; - } - } else { - if (acc->right.valid && boundedLe (scan_y, bound->right)) { - x = intersectLine (scan_y, acc->right); - } else { - if (acc->left.valid) - x = intersectLine (scan_y, acc->left); - else - x = def->w - def->l; - } - } - return x; -} - -/* - * generate the set of spans with - * the given y coordinate - */ - -static void -arcSpan ( - int y, - int lx, - int lw, - int rx, - int rw, - struct arc_def *def, - struct arc_bound *bounds, - struct accelerators *acc, - int mask) -{ - int linx, loutx, rinx, routx; - double x, altx; - - if (boundedLe (y, bounds->inneri)) { - linx = -(lx + lw); - rinx = rx; - } else { - /* - * intersection with left face - */ - x = hookX (y + acc->fromIntY, def, bounds, acc, 1); - if (acc->right.valid && - boundedLe (y + acc->fromIntY, bounds->right)) - { - altx = intersectLine (y + acc->fromIntY, acc->right); - if (altx < x) - x = altx; - } - linx = -ICEIL(acc->fromIntX - x); - rinx = ICEIL(acc->fromIntX + x); - } - if (boundedLe (y, bounds->outeri)) { - loutx = -lx; - routx = rx + rw; - } else { - /* - * intersection with right face - */ - x = hookX (y + acc->fromIntY, def, bounds, acc, 0); - if (acc->left.valid && - boundedLe (y + acc->fromIntY, bounds->left)) - { - altx = x; - x = intersectLine (y + acc->fromIntY, acc->left); - if (x < altx) - x = altx; - } - loutx = -ICEIL(acc->fromIntX - x); - routx = ICEIL(acc->fromIntX + x); - } - if (routx > rinx) { - if (mask & 1) - newFinalSpan (acc->yorgu - y, - acc->xorg + rinx, acc->xorg + routx); - if (mask & 8) - newFinalSpan (acc->yorgl + y, - acc->xorg + rinx, acc->xorg + routx); - } - if (loutx > linx) { - if (mask & 2) - newFinalSpan (acc->yorgu - y, - acc->xorg - loutx, acc->xorg - linx); - if (mask & 4) - newFinalSpan (acc->yorgl + y, - acc->xorg - loutx, acc->xorg - linx); - } -} - -static void -arcSpan0 ( - int lx, - int lw, - int rx, - int rw, - struct arc_def *def, - struct arc_bound *bounds, - struct accelerators *acc, - int mask) -{ - double x; - - if (boundedLe (0, bounds->inneri) && - acc->left.valid && boundedLe (0, bounds->left) && - acc->left.b > 0) - { - x = def->w - def->l; - if (acc->left.b < x) - x = acc->left.b; - lw = ICEIL(acc->fromIntX - x) - lx; - rw += rx; - rx = ICEIL(acc->fromIntX + x); - rw -= rx; - } - arcSpan (0, lx, lw, rx, rw, def, bounds, acc, mask); -} - -static void -tailSpan ( - int y, - int lw, - int rw, - struct arc_def *def, - struct arc_bound *bounds, - struct accelerators *acc, - int mask) -{ - double yy, xalt, x, lx, rx; - int n; - - if (boundedLe(y, bounds->outeri)) - arcSpan (y, 0, lw, -rw, rw, def, bounds, acc, mask); - else if (def->w != def->h) { - yy = y + acc->fromIntY; - x = tailX(yy, def, bounds, acc); - if (yy == 0.0 && x == -rw - acc->fromIntX) - return; - if (acc->right.valid && boundedLe (yy, bounds->right)) { - rx = x; - lx = -x; - xalt = intersectLine (yy, acc->right); - if (xalt >= -rw - acc->fromIntX && xalt <= rx) - rx = xalt; - n = ICEIL(acc->fromIntX + lx); - if (lw > n) { - if (mask & 2) - newFinalSpan (acc->yorgu - y, - acc->xorg + n, acc->xorg + lw); - if (mask & 4) - newFinalSpan (acc->yorgl + y, - acc->xorg + n, acc->xorg + lw); - } - n = ICEIL(acc->fromIntX + rx); - if (n > -rw) { - if (mask & 1) - newFinalSpan (acc->yorgu - y, - acc->xorg - rw, acc->xorg + n); - if (mask & 8) - newFinalSpan (acc->yorgl + y, - acc->xorg - rw, acc->xorg + n); - } - } - arcSpan (y, - ICEIL(acc->fromIntX - x), 0, - ICEIL(acc->fromIntX + x), 0, - def, bounds, acc, mask); - } -} - -/* - * create whole arcs out of pieces. This code is - * very bad. - */ - -static struct finalSpan **finalSpans = NULL; -static int finalMiny = 0, finalMaxy = -1; -static int finalSize = 0; - -static int nspans = 0; /* total spans, not just y coords */ - -struct finalSpan { - struct finalSpan *next; - int min, max; /* x values */ -}; - -static struct finalSpan *freeFinalSpans, *tmpFinalSpan; - -# define allocFinalSpan() (freeFinalSpans ?\ - ((tmpFinalSpan = freeFinalSpans), \ - (freeFinalSpans = freeFinalSpans->next), \ - (tmpFinalSpan->next = 0), \ - tmpFinalSpan) : \ - realAllocSpan ()) - -# define SPAN_CHUNK_SIZE 128 - -struct finalSpanChunk { - struct finalSpan data[SPAN_CHUNK_SIZE]; - struct finalSpanChunk *next; -}; - -static struct finalSpanChunk *chunks; - -static struct finalSpan * -realAllocSpan (void) -{ - struct finalSpanChunk *newChunk; - struct finalSpan *span; - int i; - - newChunk = xalloc (sizeof (struct finalSpanChunk)); - if (!newChunk) - return (struct finalSpan *) NULL; - newChunk->next = chunks; - chunks = newChunk; - freeFinalSpans = span = newChunk->data + 1; - for (i = 1; i < SPAN_CHUNK_SIZE-1; i++) { - span->next = span+1; - span++; - } - span->next = 0; - span = newChunk->data; - span->next = 0; - return span; -} - -static void -disposeFinalSpans (void) -{ - struct finalSpanChunk *chunk, *next; - - for (chunk = chunks; chunk; chunk = next) { - next = chunk->next; - xfree (chunk); - } - chunks = 0; - freeFinalSpans = 0; - xfree(finalSpans); - finalSpans = 0; -} - -static void -fillSpans ( - DrawablePtr pDrawable, - GCPtr pGC) -{ - struct finalSpan *span; - DDXPointPtr xSpan; - int *xWidth; - int i; - struct finalSpan **f; - int spany; - DDXPointPtr xSpans; - int *xWidths; - - if (nspans == 0) - return; - xSpan = xSpans = xalloc (nspans * sizeof (DDXPointRec)); - xWidth = xWidths = xalloc (nspans * sizeof (int)); - if (xSpans && xWidths) - { - i = 0; - f = finalSpans; - for (spany = finalMiny; spany <= finalMaxy; spany++, f++) { - for (span = *f; span; span=span->next) { - if (span->max <= span->min) - continue; - xSpan->x = span->min; - xSpan->y = spany; - ++xSpan; - *xWidth++ = span->max - span->min; - ++i; - } - } - (*pGC->ops->FillSpans) (pDrawable, pGC, i, xSpans, xWidths, TRUE); - } - disposeFinalSpans (); - if (xSpans) - xfree (xSpans); - if (xWidths) - xfree (xWidths); - finalMiny = 0; - finalMaxy = -1; - finalSize = 0; - nspans = 0; -} - -# define SPAN_REALLOC 100 - -# define findSpan(y) ((finalMiny <= (y) && (y) <= finalMaxy) ? \ - &finalSpans[(y) - finalMiny] : \ - realFindSpan (y)) - -static struct finalSpan ** -realFindSpan (int y) -{ - struct finalSpan **newSpans; - int newSize, newMiny, newMaxy; - int change; - int i; - - if (y < finalMiny || y > finalMaxy) { - if (!finalSize) { - finalMiny = y; - finalMaxy = y - 1; - } - if (y < finalMiny) - change = finalMiny - y; - else - change = y - finalMaxy; - if (change >= SPAN_REALLOC) - change += SPAN_REALLOC; - else - change = SPAN_REALLOC; - newSize = finalSize + change; - newSpans = xalloc(newSize * sizeof (struct finalSpan *)); - if (!newSpans) - return NULL; - newMiny = finalMiny; - newMaxy = finalMaxy; - if (y < finalMiny) - newMiny = finalMiny - change; - else - newMaxy = finalMaxy + change; - if (finalSpans) { - memmove(((char *) newSpans) + (finalMiny-newMiny) * sizeof (struct finalSpan *), - (char *) finalSpans, - finalSize * sizeof (struct finalSpan *)); - xfree (finalSpans); - } - if ((i = finalMiny - newMiny) > 0) - bzero ((char *)newSpans, i * sizeof (struct finalSpan *)); - if ((i = newMaxy - finalMaxy) > 0) - bzero ((char *)(newSpans + newSize - i), - i * sizeof (struct finalSpan *)); - finalSpans = newSpans; - finalMaxy = newMaxy; - finalMiny = newMiny; - finalSize = newSize; - } - return &finalSpans[y - finalMiny]; -} - -static void -newFinalSpan ( - int y, - int xmin, - int xmax) -{ - struct finalSpan *x; - struct finalSpan **f; - struct finalSpan *oldx; - struct finalSpan *prev; - - f = findSpan (y); - if (!f) - return; - oldx = 0; - for (;;) { - prev = 0; - for (x = *f; x; x=x->next) { - if (x == oldx) { - prev = x; - continue; - } - if (x->min <= xmax && xmin <= x->max) { - if (oldx) { - oldx->min = min (x->min, xmin); - oldx->max = max (x->max, xmax); - if (prev) - prev->next = x->next; - else - *f = x->next; - --nspans; - } else { - x->min = min (x->min, xmin); - x->max = max (x->max, xmax); - oldx = x; - } - xmin = oldx->min; - xmax = oldx->max; - break; - } - prev = x; - } - if (!x) - break; - } - if (!oldx) { - x = allocFinalSpan (); - if (x) - { - x->min = xmin; - x->max = xmax; - x->next = *f; - *f = x; - ++nspans; - } - } -} - -static void -mirrorSppPoint ( - int quadrant, - SppPointPtr sppPoint) -{ - switch (quadrant) { - case 0: - break; - case 1: - sppPoint->x = -sppPoint->x; - break; - case 2: - sppPoint->x = -sppPoint->x; - sppPoint->y = -sppPoint->y; - break; - case 3: - sppPoint->y = -sppPoint->y; - break; - } - /* - * and translate to X coordinate system - */ - sppPoint->y = -sppPoint->y; -} - -/* - * split an arc into pieces which are scan-converted - * in the first-quadrant and mirrored into position. - * This is necessary as the scan-conversion code can - * only deal with arcs completely contained in the - * first quadrant. - */ - -static void -drawArc ( - xArc *tarc, - int l, - int a0, - int a1, - miArcFacePtr right, - miArcFacePtr left) /* save end line points */ -{ - struct arc_def def; - struct accelerators acc; - int startq, endq, curq; - int rightq, leftq = 0, righta = 0, lefta = 0; - miArcFacePtr passRight, passLeft; - int q0 = 0, q1 = 0, mask; - struct band { - int a0, a1; - int mask; - } band[5], sweep[20]; - int bandno, sweepno; - int i, j; - int flipRight = 0, flipLeft = 0; - int copyEnd = 0; - miArcSpanData *spdata; - Bool mustFree; - - spdata = miComputeWideEllipse(l, tarc, &mustFree); - if (!spdata) - return; - - if (a1 < a0) - a1 += 360 * 64; - startq = a0 / (90 * 64); - if (a0 == a1) - endq = startq; - else - endq = (a1-1) / (90 * 64); - bandno = 0; - curq = startq; - rightq = -1; - for (;;) { - switch (curq) { - case 0: - if (a0 > 90 * 64) - q0 = 0; - else - q0 = a0; - if (a1 < 360 * 64) - q1 = min (a1, 90 * 64); - else - q1 = 90 * 64; - if (curq == startq && a0 == q0 && rightq < 0) { - righta = q0; - rightq = curq; - } - if (curq == endq && a1 == q1) { - lefta = q1; - leftq = curq; - } - break; - case 1: - if (a1 < 90 * 64) - q0 = 0; - else - q0 = 180 * 64 - min (a1, 180 * 64); - if (a0 > 180 * 64) - q1 = 90 * 64; - else - q1 = 180 * 64 - max (a0, 90 * 64); - if (curq == startq && 180 * 64 - a0 == q1) { - righta = q1; - rightq = curq; - } - if (curq == endq && 180 * 64 - a1 == q0) { - lefta = q0; - leftq = curq; - } - break; - case 2: - if (a0 > 270 * 64) - q0 = 0; - else - q0 = max (a0, 180 * 64) - 180 * 64; - if (a1 < 180 * 64) - q1 = 90 * 64; - else - q1 = min (a1, 270 * 64) - 180 * 64; - if (curq == startq && a0 - 180*64 == q0) { - righta = q0; - rightq = curq; - } - if (curq == endq && a1 - 180 * 64 == q1) { - lefta = q1; - leftq = curq; - } - break; - case 3: - if (a1 < 270 * 64) - q0 = 0; - else - q0 = 360 * 64 - min (a1, 360 * 64); - q1 = 360 * 64 - max (a0, 270 * 64); - if (curq == startq && 360 * 64 - a0 == q1) { - righta = q1; - rightq = curq; - } - if (curq == endq && 360 * 64 - a1 == q0) { - lefta = q0; - leftq = curq; - } - break; - } - band[bandno].a0 = q0; - band[bandno].a1 = q1; - band[bandno].mask = 1 << curq; - bandno++; - if (curq == endq) - break; - curq++; - if (curq == 4) { - a0 = 0; - a1 -= 360 * 64; - curq = 0; - endq -= 4; - } - } - sweepno = 0; - for (;;) { - q0 = 90 * 64; - mask = 0; - /* - * find left-most point - */ - for (i = 0; i < bandno; i++) - if (band[i].a0 <= q0) { - q0 = band[i].a0; - q1 = band[i].a1; - mask = band[i].mask; - } - if (!mask) - break; - /* - * locate next point of change - */ - for (i = 0; i < bandno; i++) - if (!(mask & band[i].mask)) { - if (band[i].a0 == q0) { - if (band[i].a1 < q1) - q1 = band[i].a1; - mask |= band[i].mask; - } else if (band[i].a0 < q1) - q1 = band[i].a0; - } - /* - * create a new sweep - */ - sweep[sweepno].a0 = q0; - sweep[sweepno].a1 = q1; - sweep[sweepno].mask = mask; - sweepno++; - /* - * subtract the sweep from the affected bands - */ - for (i = 0; i < bandno; i++) - if (band[i].a0 == q0) { - band[i].a0 = q1; - /* - * check if this band is empty - */ - if (band[i].a0 == band[i].a1) - band[i].a1 = band[i].a0 = 90 * 64 + 1; - } - } - computeAcc (tarc, l, &def, &acc); - for (j = 0; j < sweepno; j++) { - mask = sweep[j].mask; - passRight = passLeft = 0; - if (mask & (1 << rightq)) { - if (sweep[j].a0 == righta) - passRight = right; - else if (sweep[j].a1 == righta) { - passLeft = right; - flipRight = 1; - } - } - if (mask & (1 << leftq)) { - if (sweep[j].a1 == lefta) - { - if (passLeft) - copyEnd = 1; - passLeft = left; - } - else if (sweep[j].a0 == lefta) { - if (passRight) - copyEnd = 1; - passRight = left; - flipLeft = 1; - } - } - drawQuadrant (&def, &acc, sweep[j].a0, sweep[j].a1, mask, - passRight, passLeft, spdata); - } - /* - * when copyEnd is set, both ends of the arc were computed - * at the same time; drawQuadrant only takes one end though, - * so the left end will be the only one holding the data. Copy - * it from there. - */ - if (copyEnd) - *right = *left; - /* - * mirror the coordinates generated for the - * faces of the arc - */ - if (right) { - mirrorSppPoint (rightq, &right->clock); - mirrorSppPoint (rightq, &right->center); - mirrorSppPoint (rightq, &right->counterClock); - if (flipRight) { - SppPointRec temp; - - temp = right->clock; - right->clock = right->counterClock; - right->counterClock = temp; - } - } - if (left) { - mirrorSppPoint (leftq, &left->counterClock); - mirrorSppPoint (leftq, &left->center); - mirrorSppPoint (leftq, &left->clock); - if (flipLeft) { - SppPointRec temp; - - temp = left->clock; - left->clock = left->counterClock; - left->counterClock = temp; - } - } - if (mustFree) - xfree(spdata); -} - -static void -drawQuadrant ( - struct arc_def *def, - struct accelerators *acc, - int a0, - int a1, - int mask, - miArcFacePtr right, - miArcFacePtr left, - miArcSpanData *spdata) -{ - struct arc_bound bound; - double yy, x, xalt; - int y, miny, maxy; - int n; - miArcSpan *span; - - def->a0 = ((double) a0) / 64.0; - def->a1 = ((double) a1) / 64.0; - computeBound (def, &bound, acc, right, left); - yy = bound.inner.min; - if (bound.outer.min < yy) - yy = bound.outer.min; - miny = ICEIL(yy - acc->fromIntY); - yy = bound.inner.max; - if (bound.outer.max > yy) - yy = bound.outer.max; - maxy = floor(yy - acc->fromIntY); - y = spdata->k; - span = spdata->spans; - if (spdata->top) - { - if (a1 == 90 * 64 && (mask & 1)) - newFinalSpan (acc->yorgu - y - 1, acc->xorg, acc->xorg + 1); - span++; - } - for (n = spdata->count1; --n >= 0; ) - { - if (y < miny) - return; - if (y <= maxy) { - arcSpan (y, - span->lx, -span->lx, 0, span->lx + span->lw, - def, &bound, acc, mask); - if (span->rw + span->rx) - tailSpan (y, -span->rw, -span->rx, def, &bound, acc, mask); - } - y--; - span++; - } - if (y < miny) - return; - if (spdata->hole) - { - if (y <= maxy) - arcSpan (y, 0, 0, 0, 1, def, &bound, acc, mask & 0xc); - } - for (n = spdata->count2; --n >= 0; ) - { - if (y < miny) - return; - if (y <= maxy) - arcSpan (y, span->lx, span->lw, span->rx, span->rw, - def, &bound, acc, mask); - y--; - span++; - } - if (spdata->bot && miny <= y && y <= maxy) - { - n = mask; - if (y == miny) - n &= 0xc; - if (span->rw <= 0) { - arcSpan0 (span->lx, -span->lx, 0, span->lx + span->lw, - def, &bound, acc, n); - if (span->rw + span->rx) - tailSpan (y, -span->rw, -span->rx, def, &bound, acc, n); - } - else - arcSpan0 (span->lx, span->lw, span->rx, span->rw, - def, &bound, acc, n); - y--; - } - while (y >= miny) { - yy = y + acc->fromIntY; - if (def->w == def->h) { - xalt = def->w - def->l; - x = -sqrt(xalt * xalt - yy * yy); - } else { - x = tailX(yy, def, &bound, acc); - if (acc->left.valid && boundedLe (yy, bound.left)) { - xalt = intersectLine (yy, acc->left); - if (xalt < x) - x = xalt; - } - if (acc->right.valid && boundedLe (yy, bound.right)) { - xalt = intersectLine (yy, acc->right); - if (xalt < x) - x = xalt; - } - } - arcSpan (y, - ICEIL(acc->fromIntX - x), 0, - ICEIL(acc->fromIntX + x), 0, - def, &bound, acc, mask); - y--; - } -} +/*********************************************************** + +Copyright 1987, 1998 The Open Group + +Permission to use, copy, modify, distribute, and sell this software and its +documentation for any purpose is hereby granted without fee, provided that +the above copyright notice appear in all copies and that both that +copyright notice and this permission notice appear in supporting +documentation. + +The above copyright notice and this permission notice shall be included in +all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN +AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN +CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + +Except as contained in this notice, the name of The Open Group shall not be +used in advertising or otherwise to promote the sale, use or other dealings +in this Software without prior written authorization from The Open Group. + + +Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts. + + All Rights Reserved + +Permission to use, copy, modify, and distribute this software and its +documentation for any purpose and without fee is hereby granted, +provided that the above copyright notice appear in all copies and that +both that copyright notice and this permission notice appear in +supporting documentation, and that the name of Digital not be +used in advertising or publicity pertaining to distribution of the +software without specific, written prior permission. + +DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING +ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL +DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR +ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, +WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, +ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS +SOFTWARE. + +******************************************************************/ +/* Author: Keith Packard and Bob Scheifler */ +/* Warning: this code is toxic, do not dally very long here. */ + +#ifdef HAVE_DIX_CONFIG_H +#include +#endif + +#include +#include +#include +#include "misc.h" +#include "gcstruct.h" +#include "scrnintstr.h" +#include "pixmapstr.h" +#include "windowstr.h" +#include "mifpoly.h" +#include "mi.h" +#include "mifillarc.h" +#include + +#ifdef _MSC_VER +#define hypot _hypot +#endif + +static double miDsin(double a); +static double miDcos(double a); +static double miDasin(double v); +static double miDatan2(double dy, double dx); + +#ifndef HAVE_CBRT +static double +cbrt(double x) +{ + if (x > 0.0) + return pow(x, 1.0/3.0); + else + return -pow(-x, 1.0/3.0); +} +#endif + +/* + * some interesting sematic interpretation of the protocol: + * + * Self intersecting arcs (i.e. those spanning 360 degrees) + * never join with other arcs, and are drawn without caps + * (unless on/off dashed, in which case each dash segment + * is capped, except when the last segment meets the + * first segment, when no caps are drawn) + * + * double dash arcs are drawn in two parts, first the + * odd dashes (drawn in background) then the even dashes + * (drawn in foreground). This means that overlapping + * sections of foreground/background are drawn twice, + * first in background then in foreground. The double-draw + * occurs even when the function uses the destination values + * (e.g. xor mode). This is the same way the wide-line + * code works and should be "fixed". + * + */ + +#undef max +#undef min + +_X_INLINE static int max (const int x, const int y) +{ + return x>y? x:y; +} + +_X_INLINE static int min (const int x, const int y) +{ + return xlineWidth; + int a0, a1, startAngle, endAngle; + miArcFacePtr temp; + + if (!l) + l = 1; + + if (tarc.width == 0 || tarc.height == 0) { + drawZeroArc (pDraw, pGC, &tarc, l, left, right); + return; + } + + if (pGC->miTranslate) { + tarc.x += pDraw->x; + tarc.y += pDraw->y; + } + + a0 = tarc.angle1; + a1 = tarc.angle2; + if (a1 > FULLCIRCLE) + a1 = FULLCIRCLE; + else if (a1 < -FULLCIRCLE) + a1 = -FULLCIRCLE; + if (a1 < 0) { + startAngle = a0 + a1; + endAngle = a0; + temp = right; + right = left; + left = temp; + } else { + startAngle = a0; + endAngle = a0 + a1; + } + /* + * bounds check the two angles + */ + if (startAngle < 0) + startAngle = FULLCIRCLE - (-startAngle) % FULLCIRCLE; + if (startAngle >= FULLCIRCLE) + startAngle = startAngle % FULLCIRCLE; + if (endAngle < 0) + endAngle = FULLCIRCLE - (-endAngle) % FULLCIRCLE; + if (endAngle > FULLCIRCLE) + endAngle = (endAngle-1) % FULLCIRCLE + 1; + if ((startAngle == endAngle) && a1) { + startAngle = 0; + endAngle = FULLCIRCLE; + } + + drawArc (&tarc, l, startAngle, endAngle, right, left); +} + +/* + +Three equations combine to describe the boundaries of the arc + +x^2/w^2 + y^2/h^2 = 1 ellipse itself +(X-x)^2 + (Y-y)^2 = r^2 circle at (x, y) on the ellipse +(Y-y) = (X-x)*w^2*y/(h^2*x) normal at (x, y) on the ellipse + +These lead to a quartic relating Y and y + +y^4 - (2Y)y^3 + (Y^2 + (h^4 - w^2*r^2)/(w^2 - h^2))y^2 + - (2Y*h^4/(w^2 - h^2))y + (Y^2*h^4)/(w^2 - h^2) = 0 + +The reducible cubic obtained from this quartic is + +z^3 - (3N)z^2 - 2V = 0 + +where + +N = (Y^2 + (h^4 - w^2*r^2/(w^2 - h^2)))/6 +V = w^2*r^2*Y^2*h^4/(4 *(w^2 - h^2)^2) + +Let + +t = z - N +p = -N^2 +q = -N^3 - V + +Then we get + +t^3 + 3pt + 2q = 0 + +The discriminant of this cubic is + +D = q^2 + p^3 + +When D > 0, a real root is obtained as + +z = N + cbrt(-q+sqrt(D)) + cbrt(-q-sqrt(D)) + +When D < 0, a real root is obtained as + +z = N - 2m*cos(acos(-q/m^3)/3) + +where + +m = sqrt(|p|) * sign(q) + +Given a real root Z of the cubic, the roots of the quartic are the roots +of the two quadratics + +y^2 + ((b+A)/2)y + (Z + (bZ - d)/A) = 0 + +where + +A = +/- sqrt(8Z + b^2 - 4c) +b, c, d are the cubic, quadratic, and linear coefficients of the quartic + +Some experimentation is then required to determine which solutions +correspond to the inner and outer boundaries. + +*/ + +typedef struct { + short lx, lw, rx, rw; +} miArcSpan; + +typedef struct { + miArcSpan *spans; + int count1, count2, k; + char top, bot, hole; +} miArcSpanData; + +static void drawQuadrant(struct arc_def *def, struct accelerators *acc, + int a0, int a1, int mask, miArcFacePtr right, + miArcFacePtr left, miArcSpanData *spdata); + +static void +miComputeCircleSpans( + int lw, + xArc *parc, + miArcSpanData *spdata) +{ + miArcSpan *span; + int doinner; + int x, y, e; + int xk, yk, xm, ym, dx, dy; + int slw, inslw; + int inx = 0, iny, ine = 0; + int inxk = 0, inyk = 0, inxm = 0, inym = 0; + + doinner = -lw; + slw = parc->width - doinner; + y = parc->height >> 1; + dy = parc->height & 1; + dx = 1 - dy; + MIWIDEARCSETUP(x, y, dy, slw, e, xk, xm, yk, ym); + inslw = parc->width + doinner; + if (inslw > 0) + { + spdata->hole = spdata->top; + MIWIDEARCSETUP(inx, iny, dy, inslw, ine, inxk, inxm, inyk, inym); + } + else + { + spdata->hole = FALSE; + doinner = -y; + } + spdata->count1 = -doinner - spdata->top; + spdata->count2 = y + doinner; + span = spdata->spans; + while (y) + { + MIFILLARCSTEP(slw); + span->lx = dy - x; + if (++doinner <= 0) + { + span->lw = slw; + span->rx = 0; + span->rw = span->lx + slw; + } + else + { + MIFILLINARCSTEP(inslw); + span->lw = x - inx; + span->rx = dy - inx + inslw; + span->rw = inx - x + slw - inslw; + } + span++; + } + if (spdata->bot) + { + if (spdata->count2) + spdata->count2--; + else + { + if (lw > (int)parc->height) + span[-1].rx = span[-1].rw = -((lw - (int)parc->height) >> 1); + else + span[-1].rw = 0; + spdata->count1--; + } + } +} + +static void +miComputeEllipseSpans( + int lw, + xArc *parc, + miArcSpanData *spdata) +{ + miArcSpan *span; + double w, h, r, xorg; + double Hs, Hf, WH, K, Vk, Nk, Fk, Vr, N, Nc, Z, rs; + double A, T, b, d, x, y, t, inx, outx = 0.0, hepp, hepm; + int flip, solution; + + w = (double)parc->width / 2.0; + h = (double)parc->height / 2.0; + r = lw / 2.0; + rs = r * r; + Hs = h * h; + WH = w * w - Hs; + Nk = w * r; + Vk = (Nk * Hs) / (WH + WH); + Hf = Hs * Hs; + Nk = (Hf - Nk * Nk) / WH; + Fk = Hf / WH; + hepp = h + EPSILON; + hepm = h - EPSILON; + K = h + ((lw - 1) >> 1); + span = spdata->spans; + if (parc->width & 1) + xorg = .5; + else + xorg = 0.0; + if (spdata->top) + { + span->lx = 0; + span->lw = 1; + span++; + } + spdata->count1 = 0; + spdata->count2 = 0; + spdata->hole = (spdata->top && + (int)parc->height * lw <= (int)(parc->width * parc->width) && + lw < (int)parc->height); + for (; K > 0.0; K -= 1.0) + { + N = (K * K + Nk) / 6.0; + Nc = N * N * N; + Vr = Vk * K; + t = Nc + Vr * Vr; + d = Nc + t; + if (d < 0.0) { + d = Nc; + b = N; + if ( (b < 0.0) == (t < 0.0) ) + { + b = -b; + d = -d; + } + Z = N - 2.0 * b * cos(acos(-t / d) / 3.0); + if ( (Z < 0.0) == (Vr < 0.0) ) + flip = 2; + else + flip = 1; + } + else + { + d = Vr * sqrt(d); + Z = N + cbrt(t + d) + cbrt(t - d); + flip = 0; + } + A = sqrt((Z + Z) - Nk); + T = (Fk - Z) * K / A; + inx = 0.0; + solution = FALSE; + b = -A + K; + d = b * b - 4 * (Z + T); + if (d >= 0) + { + d = sqrt(d); + y = (b + d) / 2; + if ((y >= 0.0) && (y < hepp)) + { + solution = TRUE; + if (y > hepm) + y = h; + t = y / h; + x = w * sqrt(1 - (t * t)); + t = K - y; + if (rs - (t * t) >= 0) + t = sqrt(rs - (t * t)); + else + t = 0; + if (flip == 2) + inx = x - t; + else + outx = x + t; + } + } + b = A + K; + d = b * b - 4 * (Z - T); + /* Because of the large magnitudes involved, we lose enough precision + * that sometimes we end up with a negative value near the axis, when + * it should be positive. This is a workaround. + */ + if (d < 0 && !solution) + d = 0.0; + if (d >= 0) { + d = sqrt(d); + y = (b + d) / 2; + if (y < hepp) + { + if (y > hepm) + y = h; + t = y / h; + x = w * sqrt(1 - (t * t)); + t = K - y; + if (rs - (t * t) >= 0) + inx = x - sqrt(rs - (t * t)); + else + inx = x; + } + y = (b - d) / 2; + if (y >= 0.0) + { + if (y > hepm) + y = h; + t = y / h; + x = w * sqrt(1 - (t * t)); + t = K - y; + if (rs - (t * t) >= 0) + t = sqrt(rs - (t * t)); + else + t = 0; + if (flip == 1) + inx = x - t; + else + outx = x + t; + } + } + span->lx = ICEIL(xorg - outx); + if (inx <= 0.0) + { + spdata->count1++; + span->lw = ICEIL(xorg + outx) - span->lx; + span->rx = ICEIL(xorg + inx); + span->rw = -ICEIL(xorg - inx); + } + else + { + spdata->count2++; + span->lw = ICEIL(xorg - inx) - span->lx; + span->rx = ICEIL(xorg + inx); + span->rw = ICEIL(xorg + outx) - span->rx; + } + span++; + } + if (spdata->bot) + { + outx = w + r; + if (r >= h && r <= w) + inx = 0.0; + else if (Nk < 0.0 && -Nk < Hs) + { + inx = w * sqrt(1 + Nk / Hs) - sqrt(rs + Nk); + if (inx > w - r) + inx = w - r; + } + else + inx = w - r; + span->lx = ICEIL(xorg - outx); + if (inx <= 0.0) + { + span->lw = ICEIL(xorg + outx) - span->lx; + span->rx = ICEIL(xorg + inx); + span->rw = -ICEIL(xorg - inx); + } + else + { + span->lw = ICEIL(xorg - inx) - span->lx; + span->rx = ICEIL(xorg + inx); + span->rw = ICEIL(xorg + outx) - span->rx; + } + } + if (spdata->hole) + { + span = &spdata->spans[spdata->count1]; + span->lw = -span->lx; + span->rx = 1; + span->rw = span->lw; + spdata->count1--; + spdata->count2++; + } +} + +static double +tailX( + double K, + struct arc_def *def, + struct arc_bound *bounds, + struct accelerators *acc) +{ + double w, h, r; + double Hs, Hf, WH, Vk, Nk, Fk, Vr, N, Nc, Z, rs; + double A, T, b, d, x, y, t, hepp, hepm; + int flip, solution; + double xs[2]; + double *xp; + + w = def->w; + h = def->h; + r = def->l; + rs = r * r; + Hs = acc->h2; + WH = -acc->h2mw2; + Nk = def->w * r; + Vk = (Nk * Hs) / (WH + WH); + Hf = acc->h4; + Nk = (Hf - Nk * Nk) / WH; + if (K == 0.0) { + if (Nk < 0.0 && -Nk < Hs) { + xs[0] = w * sqrt(1 + Nk / Hs) - sqrt(rs + Nk); + xs[1] = w - r; + if (acc->left.valid && boundedLe(K, bounds->left) && + !boundedLe(K, bounds->outer) && xs[0] >= 0.0 && xs[1] >= 0.0) + return xs[1]; + if (acc->right.valid && boundedLe(K, bounds->right) && + !boundedLe(K, bounds->inner) && xs[0] <= 0.0 && xs[1] <= 0.0) + return xs[1]; + return xs[0]; + } + return w - r; + } + Fk = Hf / WH; + hepp = h + EPSILON; + hepm = h - EPSILON; + N = (K * K + Nk) / 6.0; + Nc = N * N * N; + Vr = Vk * K; + xp = xs; + xs[0] = 0.0; + t = Nc + Vr * Vr; + d = Nc + t; + if (d < 0.0) { + d = Nc; + b = N; + if ( (b < 0.0) == (t < 0.0) ) + { + b = -b; + d = -d; + } + Z = N - 2.0 * b * cos(acos(-t / d) / 3.0); + if ( (Z < 0.0) == (Vr < 0.0) ) + flip = 2; + else + flip = 1; + } + else + { + d = Vr * sqrt(d); + Z = N + cbrt(t + d) + cbrt(t - d); + flip = 0; + } + A = sqrt((Z + Z) - Nk); + T = (Fk - Z) * K / A; + solution = FALSE; + b = -A + K; + d = b * b - 4 * (Z + T); + if (d >= 0 && flip == 2) + { + d = sqrt(d); + y = (b + d) / 2; + if ((y >= 0.0) && (y < hepp)) + { + solution = TRUE; + if (y > hepm) + y = h; + t = y / h; + x = w * sqrt(1 - (t * t)); + t = K - y; + if (rs - (t * t) >= 0) + t = sqrt(rs - (t * t)); + else + t = 0; + *xp++ = x - t; + } + } + b = A + K; + d = b * b - 4 * (Z - T); + /* Because of the large magnitudes involved, we lose enough precision + * that sometimes we end up with a negative value near the axis, when + * it should be positive. This is a workaround. + */ + if (d < 0 && !solution) + d = 0.0; + if (d >= 0) { + d = sqrt(d); + y = (b + d) / 2; + if (y < hepp) + { + if (y > hepm) + y = h; + t = y / h; + x = w * sqrt(1 - (t * t)); + t = K - y; + if (rs - (t * t) >= 0) + *xp++ = x - sqrt(rs - (t * t)); + else + *xp++ = x; + } + y = (b - d) / 2; + if (y >= 0.0 && flip == 1) + { + if (y > hepm) + y = h; + t = y / h; + x = w * sqrt(1 - (t * t)); + t = K - y; + if (rs - (t * t) >= 0) + t = sqrt(rs - (t * t)); + else + t = 0; + *xp++ = x - t; + } + } + if (xp > &xs[1]) { + if (acc->left.valid && boundedLe(K, bounds->left) && + !boundedLe(K, bounds->outer) && xs[0] >= 0.0 && xs[1] >= 0.0) + return xs[1]; + if (acc->right.valid && boundedLe(K, bounds->right) && + !boundedLe(K, bounds->inner) && xs[0] <= 0.0 && xs[1] <= 0.0) + return xs[1]; + } + return xs[0]; +} + +static miArcSpanData * +miComputeWideEllipse(int lw, xArc *parc) +{ + miArcSpanData *spdata = NULL; + int k; + + if (!lw) + lw = 1; + k = (parc->height >> 1) + ((lw - 1) >> 1); + spdata = xalloc(sizeof(miArcSpanData) + sizeof(miArcSpan) * (k + 2)); + if (!spdata) + return NULL; + spdata->spans = (miArcSpan *)(spdata + 1); + spdata->k = k; + spdata->top = !(lw & 1) && !(parc->width & 1); + spdata->bot = !(parc->height & 1); + if (parc->width == parc->height) + miComputeCircleSpans(lw, parc, spdata); + else + miComputeEllipseSpans(lw, parc, spdata); + return spdata; +} + +static void +miFillWideEllipse( + DrawablePtr pDraw, + GCPtr pGC, + xArc *parc) +{ + DDXPointPtr points; + DDXPointPtr pts; + int *widths; + int *wids; + miArcSpanData *spdata; + miArcSpan *span; + int xorg, yorgu, yorgl; + int n; + + yorgu = parc->height + pGC->lineWidth; + n = (sizeof(int) * 2) * yorgu; + widths = xalloc(n + (sizeof(DDXPointRec) * 2) * yorgu); + if (!widths) + return; + points = (DDXPointPtr)((char *)widths + n); + spdata = miComputeWideEllipse((int)pGC->lineWidth, parc); + if (!spdata) + { + xfree(widths); + return; + } + pts = points; + wids = widths; + span = spdata->spans; + xorg = parc->x + (parc->width >> 1); + yorgu = parc->y + (parc->height >> 1); + yorgl = yorgu + (parc->height & 1); + if (pGC->miTranslate) + { + xorg += pDraw->x; + yorgu += pDraw->y; + yorgl += pDraw->y; + } + yorgu -= spdata->k; + yorgl += spdata->k; + if (spdata->top) + { + pts->x = xorg; + pts->y = yorgu - 1; + pts++; + *wids++ = 1; + span++; + } + for (n = spdata->count1; --n >= 0; ) + { + pts[0].x = xorg + span->lx; + pts[0].y = yorgu; + wids[0] = span->lw; + pts[1].x = pts[0].x; + pts[1].y = yorgl; + wids[1] = wids[0]; + yorgu++; + yorgl--; + pts += 2; + wids += 2; + span++; + } + if (spdata->hole) + { + pts[0].x = xorg; + pts[0].y = yorgl; + wids[0] = 1; + pts++; + wids++; + } + for (n = spdata->count2; --n >= 0; ) + { + pts[0].x = xorg + span->lx; + pts[0].y = yorgu; + wids[0] = span->lw; + pts[1].x = xorg + span->rx; + pts[1].y = pts[0].y; + wids[1] = span->rw; + pts[2].x = pts[0].x; + pts[2].y = yorgl; + wids[2] = wids[0]; + pts[3].x = pts[1].x; + pts[3].y = pts[2].y; + wids[3] = wids[1]; + yorgu++; + yorgl--; + pts += 4; + wids += 4; + span++; + } + if (spdata->bot) + { + if (span->rw <= 0) + { + pts[0].x = xorg + span->lx; + pts[0].y = yorgu; + wids[0] = span->lw; + pts++; + wids++; + } + else + { + pts[0].x = xorg + span->lx; + pts[0].y = yorgu; + wids[0] = span->lw; + pts[1].x = xorg + span->rx; + pts[1].y = pts[0].y; + wids[1] = span->rw; + pts += 2; + wids += 2; + } + } + xfree(spdata); + (*pGC->ops->FillSpans)(pDraw, pGC, pts - points, points, widths, FALSE); + + xfree(widths); +} + +/* + * miPolyArc strategy: + * + * If arc is zero width and solid, we don't have to worry about the rasterop + * or join styles. For wide solid circles, we use a fast integer algorithm. + * For wide solid ellipses, we use special case floating point code. + * Otherwise, we set up pDrawTo and pGCTo according to the rasterop, then + * draw using pGCTo and pDrawTo. If the raster-op was "tricky," that is, + * if it involves the destination, then we use PushPixels to move the bits + * from the scratch drawable to pDraw. (See the wide line code for a + * fuller explanation of this.) + */ + +void +miPolyArc(DrawablePtr pDraw, GCPtr pGC, int narcs, xArc *parcs) +{ + int i; + xArc *parc; + int xMin, xMax, yMin, yMax; + int pixmapWidth = 0, pixmapHeight = 0; + int xOrg = 0, yOrg = 0; + int width; + Bool fTricky; + DrawablePtr pDrawTo; + CARD32 fg, bg; + GCPtr pGCTo; + miPolyArcPtr polyArcs; + int cap[2], join[2]; + int iphase; + int halfWidth; + + width = pGC->lineWidth; + if(width == 0 && pGC->lineStyle == LineSolid) + { + for(i = narcs, parc = parcs; --i >= 0; parc++) + miArcSegment( pDraw, pGC, *parc, + (miArcFacePtr) 0, (miArcFacePtr) 0 ); + fillSpans (pDraw, pGC); + } + else + { + if ((pGC->lineStyle == LineSolid) && narcs) + { + while (parcs->width && parcs->height && + (parcs->angle2 >= FULLCIRCLE || + parcs->angle2 <= -FULLCIRCLE)) + { + miFillWideEllipse(pDraw, pGC, parcs); + if (!--narcs) + return; + parcs++; + } + } + + /* Set up pDrawTo and pGCTo based on the rasterop */ + switch(pGC->alu) + { + case GXclear: /* 0 */ + case GXcopy: /* src */ + case GXcopyInverted: /* NOT src */ + case GXset: /* 1 */ + fTricky = FALSE; + pDrawTo = pDraw; + pGCTo = pGC; + break; + default: + fTricky = TRUE; + + /* find bounding box around arcs */ + xMin = yMin = MAXSHORT; + xMax = yMax = MINSHORT; + + for(i = narcs, parc = parcs; --i >= 0; parc++) + { + xMin = min (xMin, parc->x); + yMin = min (yMin, parc->y); + xMax = max (xMax, (parc->x + (int) parc->width)); + yMax = max (yMax, (parc->y + (int) parc->height)); + } + + /* expand box to deal with line widths */ + halfWidth = (width + 1)/2; + xMin -= halfWidth; + yMin -= halfWidth; + xMax += halfWidth; + yMax += halfWidth; + + /* compute pixmap size; limit it to size of drawable */ + xOrg = max(xMin, 0); + yOrg = max(yMin, 0); + pixmapWidth = min(xMax, pDraw->width) - xOrg; + pixmapHeight = min(yMax, pDraw->height) - yOrg; + + /* if nothing left, return */ + if ( (pixmapWidth <= 0) || (pixmapHeight <= 0) ) return; + + for(i = narcs, parc = parcs; --i >= 0; parc++) + { + parc->x -= xOrg; + parc->y -= yOrg; + } + if (pGC->miTranslate) + { + xOrg += pDraw->x; + yOrg += pDraw->y; + } + + /* set up scratch GC */ + + pGCTo = GetScratchGC(1, pDraw->pScreen); + if (!pGCTo) + return; + gcvals[GCValsFunction] = GXcopy; + gcvals[GCValsForeground] = 1; + gcvals[GCValsBackground] = 0; + gcvals[GCValsLineWidth] = pGC->lineWidth; + gcvals[GCValsCapStyle] = pGC->capStyle; + gcvals[GCValsJoinStyle] = pGC->joinStyle; + dixChangeGC(NullClient, pGCTo, GCValsMask, gcvals, NULL); + + /* allocate a 1 bit deep pixmap of the appropriate size, and + * validate it */ + pDrawTo = (DrawablePtr)(*pDraw->pScreen->CreatePixmap) + (pDraw->pScreen, pixmapWidth, pixmapHeight, 1, + CREATE_PIXMAP_USAGE_SCRATCH); + if (!pDrawTo) + { + FreeScratchGC(pGCTo); + return; + } + ValidateGC(pDrawTo, pGCTo); + miClearDrawable(pDrawTo, pGCTo); + } + + fg = pGC->fgPixel; + bg = pGC->bgPixel; + if ((pGC->fillStyle == FillTiled) || + (pGC->fillStyle == FillOpaqueStippled)) + bg = fg; /* the protocol sez these don't cause color changes */ + + polyArcs = miComputeArcs (parcs, narcs, pGC); + + if (!polyArcs) + { + if (fTricky) { + (*pDraw->pScreen->DestroyPixmap) ((PixmapPtr)pDrawTo); + FreeScratchGC (pGCTo); + } + return; + } + + cap[0] = cap[1] = 0; + join[0] = join[1] = 0; + for (iphase = ((pGC->lineStyle == LineDoubleDash) ? 1 : 0); + iphase >= 0; + iphase--) + { + if (iphase == 1) { + dixChangeGC (NullClient, pGC, GCForeground, &bg, NULL); + ValidateGC (pDraw, pGC); + } else if (pGC->lineStyle == LineDoubleDash) { + dixChangeGC (NullClient, pGC, GCForeground, &fg, NULL); + ValidateGC (pDraw, pGC); + } + for (i = 0; i < polyArcs[iphase].narcs; i++) { + miArcDataPtr arcData; + + arcData = &polyArcs[iphase].arcs[i]; + miArcSegment(pDrawTo, pGCTo, arcData->arc, + &arcData->bounds[RIGHT_END], + &arcData->bounds[LEFT_END]); + if (polyArcs[iphase].arcs[i].render) { + fillSpans (pDrawTo, pGCTo); + /* + * don't cap self-joining arcs + */ + if (polyArcs[iphase].arcs[i].selfJoin && + cap[iphase] < polyArcs[iphase].arcs[i].cap) + cap[iphase]++; + while (cap[iphase] < polyArcs[iphase].arcs[i].cap) { + int arcIndex, end; + miArcDataPtr arcData0; + + arcIndex = polyArcs[iphase].caps[cap[iphase]].arcIndex; + end = polyArcs[iphase].caps[cap[iphase]].end; + arcData0 = &polyArcs[iphase].arcs[arcIndex]; + miArcCap (pDrawTo, pGCTo, + &arcData0->bounds[end], end, + arcData0->arc.x, arcData0->arc.y, + (double) arcData0->arc.width / 2.0, + (double) arcData0->arc.height / 2.0); + ++cap[iphase]; + } + while (join[iphase] < polyArcs[iphase].arcs[i].join) { + int arcIndex0, arcIndex1, end0, end1; + int phase0, phase1; + miArcDataPtr arcData0, arcData1; + miArcJoinPtr joinp; + + joinp = &polyArcs[iphase].joins[join[iphase]]; + arcIndex0 = joinp->arcIndex0; + end0 = joinp->end0; + arcIndex1 = joinp->arcIndex1; + end1 = joinp->end1; + phase0 = joinp->phase0; + phase1 = joinp->phase1; + arcData0 = &polyArcs[phase0].arcs[arcIndex0]; + arcData1 = &polyArcs[phase1].arcs[arcIndex1]; + miArcJoin (pDrawTo, pGCTo, + &arcData0->bounds[end0], + &arcData1->bounds[end1], + arcData0->arc.x, arcData0->arc.y, + (double) arcData0->arc.width / 2.0, + (double) arcData0->arc.height / 2.0, + arcData1->arc.x, arcData1->arc.y, + (double) arcData1->arc.width / 2.0, + (double) arcData1->arc.height / 2.0); + ++join[iphase]; + } + if (fTricky) { + if (pGC->serialNumber != pDraw->serialNumber) + ValidateGC (pDraw, pGC); + (*pGC->ops->PushPixels) (pGC, (PixmapPtr)pDrawTo, + pDraw, pixmapWidth, pixmapHeight, xOrg, yOrg); + miClearDrawable ((DrawablePtr) pDrawTo, pGCTo); + } + } + } + } + miFreeArcs(polyArcs, pGC); + + if(fTricky) + { + (*pGCTo->pScreen->DestroyPixmap)((PixmapPtr)pDrawTo); + FreeScratchGC(pGCTo); + } + } +} + +static double +angleBetween (SppPointRec center, SppPointRec point1, SppPointRec point2) +{ + double a1, a2, a; + + /* + * reflect from X coordinates back to ellipse + * coordinates -- y increasing upwards + */ + a1 = miDatan2 (- (point1.y - center.y), point1.x - center.x); + a2 = miDatan2 (- (point2.y - center.y), point2.x - center.x); + a = a2 - a1; + if (a <= -180.0) + a += 360.0; + else if (a > 180.0) + a -= 360.0; + return a; +} + +static void +translateBounds ( + miArcFacePtr b, + int x, + int y, + double fx, + double fy) +{ + fx += x; + fy += y; + b->clock.x -= fx; + b->clock.y -= fy; + b->center.x -= fx; + b->center.y -= fy; + b->counterClock.x -= fx; + b->counterClock.y -= fy; +} + +static void +miArcJoin(DrawablePtr pDraw, GCPtr pGC, miArcFacePtr pLeft, + miArcFacePtr pRight, int xOrgLeft, int yOrgLeft, + double xFtransLeft, double yFtransLeft, + int xOrgRight, int yOrgRight, + double xFtransRight, double yFtransRight) +{ + SppPointRec center, corner, otherCorner; + SppPointRec poly[5], e; + SppPointPtr pArcPts; + int cpt; + SppArcRec arc; + miArcFaceRec Right, Left; + int polyLen = 0; + int xOrg, yOrg; + double xFtrans, yFtrans; + double a; + double ae, ac2, ec2, bc2, de; + double width; + + xOrg = (xOrgRight + xOrgLeft) / 2; + yOrg = (yOrgRight + yOrgLeft) / 2; + xFtrans = (xFtransLeft + xFtransRight) / 2; + yFtrans = (yFtransLeft + yFtransRight) / 2; + Right = *pRight; + translateBounds (&Right, xOrg - xOrgRight, yOrg - yOrgRight, + xFtrans - xFtransRight, yFtrans - yFtransRight); + Left = *pLeft; + translateBounds (&Left, xOrg - xOrgLeft, yOrg - yOrgLeft, + xFtrans - xFtransLeft, yFtrans - yFtransLeft); + pRight = &Right; + pLeft = &Left; + + if (pRight->clock.x == pLeft->counterClock.x && + pRight->clock.y == pLeft->counterClock.y) + return; + center = pRight->center; + if (0 <= (a = angleBetween (center, pRight->clock, pLeft->counterClock)) + && a <= 180.0) + { + corner = pRight->clock; + otherCorner = pLeft->counterClock; + } else { + a = angleBetween (center, pLeft->clock, pRight->counterClock); + corner = pLeft->clock; + otherCorner = pRight->counterClock; + } + switch (pGC->joinStyle) { + case JoinRound: + width = (pGC->lineWidth ? (double)pGC->lineWidth : (double)1); + + arc.x = center.x - width/2; + arc.y = center.y - width/2; + arc.width = width; + arc.height = width; + arc.angle1 = -miDatan2 (corner.y - center.y, corner.x - center.x); + arc.angle2 = a; + pArcPts = xalloc (3 * sizeof (SppPointRec)); + if (!pArcPts) + return; + pArcPts[0].x = otherCorner.x; + pArcPts[0].y = otherCorner.y; + pArcPts[1].x = center.x; + pArcPts[1].y = center.y; + pArcPts[2].x = corner.x; + pArcPts[2].y = corner.y; + if( (cpt = miGetArcPts(&arc, 3, &pArcPts)) ) + { + /* by drawing with miFillSppPoly and setting the endpoints of the arc + * to be the corners, we assure that the cap will meet up with the + * rest of the line */ + miFillSppPoly(pDraw, pGC, cpt, pArcPts, xOrg, yOrg, xFtrans, yFtrans); + } + xfree(pArcPts); + return; + case JoinMiter: + /* + * don't miter arcs with less than 11 degrees between them + */ + if (a < 169.0) { + poly[0] = corner; + poly[1] = center; + poly[2] = otherCorner; + bc2 = (corner.x - otherCorner.x) * (corner.x - otherCorner.x) + + (corner.y - otherCorner.y) * (corner.y - otherCorner.y); + ec2 = bc2 / 4; + ac2 = (corner.x - center.x) * (corner.x - center.x) + + (corner.y - center.y) * (corner.y - center.y); + ae = sqrt (ac2 - ec2); + de = ec2 / ae; + e.x = (corner.x + otherCorner.x) / 2; + e.y = (corner.y + otherCorner.y) / 2; + poly[3].x = e.x + de * (e.x - center.x) / ae; + poly[3].y = e.y + de * (e.y - center.y) / ae; + poly[4] = corner; + polyLen = 5; + break; + } + case JoinBevel: + poly[0] = corner; + poly[1] = center; + poly[2] = otherCorner; + poly[3] = corner; + polyLen = 4; + break; + } + miFillSppPoly (pDraw, pGC, polyLen, poly, xOrg, yOrg, xFtrans, yFtrans); +} + +/*ARGSUSED*/ +static void +miArcCap ( + DrawablePtr pDraw, + GCPtr pGC, + miArcFacePtr pFace, + int end, + int xOrg, + int yOrg, + double xFtrans, + double yFtrans) +{ + SppPointRec corner, otherCorner, center, endPoint, poly[5]; + + corner = pFace->clock; + otherCorner = pFace->counterClock; + center = pFace->center; + switch (pGC->capStyle) { + case CapProjecting: + poly[0].x = otherCorner.x; + poly[0].y = otherCorner.y; + poly[1].x = corner.x; + poly[1].y = corner.y; + poly[2].x = corner.x - + (center.y - corner.y); + poly[2].y = corner.y + + (center.x - corner.x); + poly[3].x = otherCorner.x - + (otherCorner.y - center.y); + poly[3].y = otherCorner.y + + (otherCorner.x - center.x); + poly[4].x = otherCorner.x; + poly[4].y = otherCorner.y; + miFillSppPoly (pDraw, pGC, 5, poly, xOrg, yOrg, xFtrans, yFtrans); + break; + case CapRound: + /* + * miRoundCap just needs these to be unequal. + */ + endPoint = center; + endPoint.x = endPoint.x + 100; + miRoundCap (pDraw, pGC, center, endPoint, corner, otherCorner, 0, + -xOrg, -yOrg, xFtrans, yFtrans); + break; + } +} + +/* MIROUNDCAP -- a private helper function + * Put Rounded cap on end. pCenter is the center of this end of the line + * pEnd is the center of the other end of the line. pCorner is one of the + * two corners at this end of the line. + * NOTE: pOtherCorner must be counter-clockwise from pCorner. + */ +/*ARGSUSED*/ +static void +miRoundCap( + DrawablePtr pDraw, + GCPtr pGC, + SppPointRec pCenter, + SppPointRec pEnd, + SppPointRec pCorner, + SppPointRec pOtherCorner, + int fLineEnd, + int xOrg, + int yOrg, + double xFtrans, + double yFtrans) +{ + int cpt; + double width; + SppArcRec arc; + SppPointPtr pArcPts; + + width = (pGC->lineWidth ? (double)pGC->lineWidth : (double)1); + + arc.x = pCenter.x - width/2; + arc.y = pCenter.y - width/2; + arc.width = width; + arc.height = width; + arc.angle1 = -miDatan2 (pCorner.y - pCenter.y, pCorner.x - pCenter.x); + if(PTISEQUAL(pCenter, pEnd)) + arc.angle2 = - 180.0; + else { + arc.angle2 = -miDatan2 (pOtherCorner.y - pCenter.y, pOtherCorner.x - pCenter.x) - arc.angle1; + if (arc.angle2 < 0) + arc.angle2 += 360.0; + } + pArcPts = (SppPointPtr) NULL; + if( (cpt = miGetArcPts(&arc, 0, &pArcPts)) ) + { + /* by drawing with miFillSppPoly and setting the endpoints of the arc + * to be the corners, we assure that the cap will meet up with the + * rest of the line */ + miFillSppPoly(pDraw, pGC, cpt, pArcPts, -xOrg, -yOrg, xFtrans, yFtrans); + } + xfree(pArcPts); +} + +/* + * To avoid inaccuracy at the cardinal points, use trig functions + * which are exact for those angles + */ + +#ifndef M_PI +#define M_PI 3.14159265358979323846 +#endif +#ifndef M_PI_2 +#define M_PI_2 1.57079632679489661923 +#endif + +# define Dsin(d) ((d) == 0.0 ? 0.0 : ((d) == 90.0 ? 1.0 : sin(d*M_PI/180.0))) +# define Dcos(d) ((d) == 0.0 ? 1.0 : ((d) == 90.0 ? 0.0 : cos(d*M_PI/180.0))) +# define mod(a,b) ((a) >= 0 ? (a) % (b) : (b) - (-(a)) % (b)) + +static double +miDcos (double a) +{ + int i; + + if (floor (a/90) == a/90) { + i = (int) (a/90.0); + switch (mod (i, 4)) { + case 0: return 1; + case 1: return 0; + case 2: return -1; + case 3: return 0; + } + } + return cos (a * M_PI / 180.0); +} + +static double +miDsin (double a) +{ + int i; + + if (floor (a/90) == a/90) { + i = (int) (a/90.0); + switch (mod (i, 4)) { + case 0: return 0; + case 1: return 1; + case 2: return 0; + case 3: return -1; + } + } + return sin (a * M_PI / 180.0); +} + +static double +miDasin (double v) +{ + if (v == 0) + return 0.0; + if (v == 1.0) + return 90.0; + if (v == -1.0) + return -90.0; + return asin(v) * (180.0 / M_PI); +} + +static double +miDatan2 (double dy, double dx) +{ + if (dy == 0) { + if (dx >= 0) + return 0.0; + return 180.0; + } else if (dx == 0) { + if (dy > 0) + return 90.0; + return -90.0; + } else if (Fabs (dy) == Fabs (dx)) { + if (dy > 0) { + if (dx > 0) + return 45.0; + return 135.0; + } else { + if (dx > 0) + return 315.0; + return 225.0; + } + } else { + return atan2 (dy, dx) * (180.0 / M_PI); + } +} + +/* MIGETARCPTS -- Converts an arc into a set of line segments -- a helper + * routine for filled arc and line (round cap) code. + * Returns the number of points in the arc. Note that it takes a pointer + * to a pointer to where it should put the points and an index (cpt). + * This procedure allocates the space necessary to fit the arc points. + * Sometimes it's convenient for those points to be at the end of an existing + * array. (For example, if we want to leave a spare point to make sectors + * instead of segments.) So we pass in the xalloc()ed chunk that contains the + * array and an index saying where we should start stashing the points. + * If there isn't an array already, we just pass in a null pointer and + * count on xrealloc() to handle the null pointer correctly. + */ +static int +miGetArcPts( + SppArcPtr parc, /* points to an arc */ + int cpt, /* number of points already in arc list */ + SppPointPtr *ppPts) /* pointer to pointer to arc-list -- modified */ +{ + double st, /* Start Theta, start angle */ + et, /* End Theta, offset from start theta */ + dt, /* Delta Theta, angle to sweep ellipse */ + cdt, /* Cos Delta Theta, actually 2 cos(dt) */ + x0, y0, /* the recurrence formula needs two points to start */ + x1, y1, + x2, y2, /* this will be the new point generated */ + xc, yc; /* the center point */ + int count, i; + SppPointPtr poly; + + /* The spec says that positive angles indicate counterclockwise motion. + * Given our coordinate system (with 0,0 in the upper left corner), + * the screen appears flipped in Y. The easiest fix is to negate the + * angles given */ + + st = - parc->angle1; + + et = - parc->angle2; + + /* Try to get a delta theta that is within 1/2 pixel. Then adjust it + * so that it divides evenly into the total. + * I'm just using cdt 'cause I'm lazy. + */ + cdt = parc->width; + if (parc->height > cdt) + cdt = parc->height; + cdt /= 2.0; + if(cdt <= 0) + return 0; + if (cdt < 1.0) + cdt = 1.0; + dt = miDasin ( 1.0 / cdt ); /* minimum step necessary */ + count = et/dt; + count = abs(count) + 1; + dt = et/count; + count++; + + cdt = 2 * miDcos(dt); + if (!(poly = (SppPointPtr) xrealloc((pointer)*ppPts, + (cpt + count) * sizeof(SppPointRec)))) + return(0); + *ppPts = poly; + + xc = parc->width/2.0; /* store half width and half height */ + yc = parc->height/2.0; + + x0 = xc * miDcos(st); + y0 = yc * miDsin(st); + x1 = xc * miDcos(st + dt); + y1 = yc * miDsin(st + dt); + xc += parc->x; /* by adding initial point, these become */ + yc += parc->y; /* the center point */ + + poly[cpt].x = (xc + x0); + poly[cpt].y = (yc + y0); + poly[cpt + 1].x = (xc + x1); + poly[cpt + 1].y = (yc + y1); + + for(i = 2; i < count; i++) + { + x2 = cdt * x1 - x0; + y2 = cdt * y1 - y0; + + poly[cpt + i].x = (xc + x2); + poly[cpt + i].y = (yc + y2); + + x0 = x1; y0 = y1; + x1 = x2; y1 = y2; + } + /* adjust the last point */ + if (abs(parc->angle2) >= 360.0) + poly[cpt +i -1] = poly[0]; + else { + poly[cpt +i -1].x = (miDcos(st + et) * parc->width/2.0 + xc); + poly[cpt +i -1].y = (miDsin(st + et) * parc->height/2.0 + yc); + } + + return(count); +} + +struct arcData { + double x0, y0, x1, y1; + int selfJoin; +}; + +# define ADD_REALLOC_STEP 20 + +static void +addCap ( + miArcCapPtr *capsp, + int *ncapsp, + int *sizep, + int end, + int arcIndex) +{ + int newsize; + miArcCapPtr cap; + + if (*ncapsp == *sizep) + { + newsize = *sizep + ADD_REALLOC_STEP; + cap = (miArcCapPtr) xrealloc (*capsp, + newsize * sizeof (**capsp)); + if (!cap) + return; + *sizep = newsize; + *capsp = cap; + } + cap = &(*capsp)[*ncapsp]; + cap->end = end; + cap->arcIndex = arcIndex; + ++*ncapsp; +} + +static void +addJoin ( + miArcJoinPtr *joinsp, + int *njoinsp, + int *sizep, + int end0, + int index0, + int phase0, + int end1, + int index1, + int phase1) +{ + int newsize; + miArcJoinPtr join; + + if (*njoinsp == *sizep) + { + newsize = *sizep + ADD_REALLOC_STEP; + join = (miArcJoinPtr) xrealloc (*joinsp, + newsize * sizeof (**joinsp)); + if (!join) + return; + *sizep = newsize; + *joinsp = join; + } + join = &(*joinsp)[*njoinsp]; + join->end0 = end0; + join->arcIndex0 = index0; + join->phase0 = phase0; + join->end1 = end1; + join->arcIndex1 = index1; + join->phase1 = phase1; + ++*njoinsp; +} + +static miArcDataPtr +addArc ( + miArcDataPtr *arcsp, + int *narcsp, + int *sizep, + xArc *xarc) +{ + int newsize; + miArcDataPtr arc; + + if (*narcsp == *sizep) + { + newsize = *sizep + ADD_REALLOC_STEP; + arc = (miArcDataPtr) xrealloc (*arcsp, + newsize * sizeof (**arcsp)); + if (!arc) + return NULL; + *sizep = newsize; + *arcsp = arc; + } + arc = &(*arcsp)[*narcsp]; + arc->arc = *xarc; + ++*narcsp; + return arc; +} + +static void +miFreeArcs( + miPolyArcPtr arcs, + GCPtr pGC) +{ + int iphase; + + for (iphase = ((pGC->lineStyle == LineDoubleDash) ? 1 : 0); + iphase >= 0; + iphase--) + { + if (arcs[iphase].narcs > 0) + xfree(arcs[iphase].arcs); + if (arcs[iphase].njoins > 0) + xfree(arcs[iphase].joins); + if (arcs[iphase].ncaps > 0) + xfree(arcs[iphase].caps); + } + xfree(arcs); +} + +/* + * map angles to radial distance. This only deals with the first quadrant + */ + +/* + * a polygonal approximation to the arc for computing arc lengths + */ + +# define DASH_MAP_SIZE 91 + +# define dashIndexToAngle(di) ((((double) (di)) * 90.0) / ((double) DASH_MAP_SIZE - 1)) +# define xAngleToDashIndex(xa) ((((long) (xa)) * (DASH_MAP_SIZE - 1)) / (90 * 64)) +# define dashIndexToXAngle(di) ((((long) (di)) * (90 * 64)) / (DASH_MAP_SIZE - 1)) +# define dashXAngleStep (((double) (90 * 64)) / ((double) (DASH_MAP_SIZE - 1))) + +typedef struct { + double map[DASH_MAP_SIZE]; +} dashMap; + +static int computeAngleFromPath(int startAngle, int endAngle, dashMap *map, + int *lenp, int backwards); + +static void +computeDashMap ( + xArc *arcp, + dashMap *map) +{ + int di; + double a, x, y, prevx = 0.0, prevy = 0.0, dist; + + for (di = 0; di < DASH_MAP_SIZE; di++) { + a = dashIndexToAngle (di); + x = ((double) arcp->width / 2.0) * miDcos (a); + y = ((double) arcp->height / 2.0) * miDsin (a); + if (di == 0) { + map->map[di] = 0.0; + } else { + dist = hypot (x - prevx, y - prevy); + map->map[di] = map->map[di - 1] + dist; + } + prevx = x; + prevy = y; + } +} + +typedef enum {HORIZONTAL, VERTICAL, OTHER} arcTypes; + +/* this routine is a bit gory */ + +static miPolyArcPtr +miComputeArcs ( + xArc *parcs, + int narcs, + GCPtr pGC) +{ + int isDashed, isDoubleDash; + int dashOffset; + miPolyArcPtr arcs; + int start, i, j, k = 0, nexti, nextk = 0; + int joinSize[2]; + int capSize[2]; + int arcSize[2]; + int angle2; + double a0, a1; + struct arcData *data; + miArcDataPtr arc; + xArc xarc; + int iphase, prevphase = 0, joinphase; + int arcsJoin; + int selfJoin; + + int iDash = 0, dashRemaining = 0; + int iDashStart = 0, dashRemainingStart = 0, iphaseStart; + int startAngle, spanAngle, endAngle, backwards = 0; + int prevDashAngle, dashAngle; + dashMap map; + + isDashed = !(pGC->lineStyle == LineSolid); + isDoubleDash = (pGC->lineStyle == LineDoubleDash); + dashOffset = pGC->dashOffset; + + data = xalloc (narcs * sizeof (struct arcData)); + if (!data) + return NULL; + arcs = xalloc (sizeof (*arcs) * (isDoubleDash ? 2 : 1)); + if (!arcs) + { + xfree(data); + return NULL; + } + for (i = 0; i < narcs; i++) { + a0 = todeg (parcs[i].angle1); + angle2 = parcs[i].angle2; + if (angle2 > FULLCIRCLE) + angle2 = FULLCIRCLE; + else if (angle2 < -FULLCIRCLE) + angle2 = -FULLCIRCLE; + data[i].selfJoin = angle2 == FULLCIRCLE || angle2 == -FULLCIRCLE; + a1 = todeg (parcs[i].angle1 + angle2); + data[i].x0 = parcs[i].x + (double) parcs[i].width / 2 * (1 + miDcos (a0)); + data[i].y0 = parcs[i].y + (double) parcs[i].height / 2 * (1 - miDsin (a0)); + data[i].x1 = parcs[i].x + (double) parcs[i].width / 2 * (1 + miDcos (a1)); + data[i].y1 = parcs[i].y + (double) parcs[i].height / 2 * (1 - miDsin (a1)); + } + + for (iphase = 0; iphase < (isDoubleDash ? 2 : 1); iphase++) { + arcs[iphase].njoins = 0; + arcs[iphase].joins = 0; + joinSize[iphase] = 0; + + arcs[iphase].ncaps = 0; + arcs[iphase].caps = 0; + capSize[iphase] = 0; + + arcs[iphase].narcs = 0; + arcs[iphase].arcs = 0; + arcSize[iphase] = 0; + } + + iphase = 0; + if (isDashed) { + iDash = 0; + dashRemaining = pGC->dash[0]; + while (dashOffset > 0) { + if (dashOffset >= dashRemaining) { + dashOffset -= dashRemaining; + iphase = iphase ? 0 : 1; + iDash++; + if (iDash == pGC->numInDashList) + iDash = 0; + dashRemaining = pGC->dash[iDash]; + } else { + dashRemaining -= dashOffset; + dashOffset = 0; + } + } + iDashStart = iDash; + dashRemainingStart = dashRemaining; + } + iphaseStart = iphase; + + for (i = narcs - 1; i >= 0; i--) { + j = i + 1; + if (j == narcs) + j = 0; + if (data[i].selfJoin || i == j || + (UNEQUAL (data[i].x1, data[j].x0) || + UNEQUAL (data[i].y1, data[j].y0))) + { + if (iphase == 0 || isDoubleDash) + addCap (&arcs[iphase].caps, &arcs[iphase].ncaps, + &capSize[iphase], RIGHT_END, 0); + break; + } + } + start = i + 1; + if (start == narcs) + start = 0; + i = start; + for (;;) { + j = i + 1; + if (j == narcs) + j = 0; + nexti = i+1; + if (nexti == narcs) + nexti = 0; + if (isDashed) { + /* + ** deal with dashed arcs. Use special rules for certain 0 area arcs. + ** Presumably, the other 0 area arcs still aren't done right. + */ + arcTypes arcType = OTHER; + CARD16 thisLength; + + if (parcs[i].height == 0 + && (parcs[i].angle1 % FULLCIRCLE) == 0x2d00 + && parcs[i].angle2 == 0x2d00) + arcType = HORIZONTAL; + else if (parcs[i].width == 0 + && (parcs[i].angle1 % FULLCIRCLE) == 0x1680 + && parcs[i].angle2 == 0x2d00) + arcType = VERTICAL; + if (arcType == OTHER) { + /* + * precompute an approximation map + */ + computeDashMap (&parcs[i], &map); + /* + * compute each individual dash segment using the path + * length function + */ + startAngle = parcs[i].angle1; + spanAngle = parcs[i].angle2; + if (spanAngle > FULLCIRCLE) + spanAngle = FULLCIRCLE; + else if (spanAngle < -FULLCIRCLE) + spanAngle = -FULLCIRCLE; + if (startAngle < 0) + startAngle = FULLCIRCLE - (-startAngle) % FULLCIRCLE; + if (startAngle >= FULLCIRCLE) + startAngle = startAngle % FULLCIRCLE; + endAngle = startAngle + spanAngle; + backwards = spanAngle < 0; + } else { + xarc = parcs[i]; + if (arcType == VERTICAL) { + xarc.angle1 = 0x1680; + startAngle = parcs[i].y; + endAngle = startAngle + parcs[i].height; + } else { + xarc.angle1 = 0x2d00; + startAngle = parcs[i].x; + endAngle = startAngle + parcs[i].width; + } + } + dashAngle = startAngle; + selfJoin = data[i].selfJoin && + (iphase == 0 || isDoubleDash); + /* + * add dashed arcs to each bucket + */ + arc = 0; + while (dashAngle != endAngle) { + prevDashAngle = dashAngle; + if (arcType == OTHER) { + dashAngle = computeAngleFromPath (prevDashAngle, endAngle, + &map, &dashRemaining, backwards); + /* avoid troubles with huge arcs and small dashes */ + if (dashAngle == prevDashAngle) { + if (backwards) + dashAngle--; + else + dashAngle++; + } + } else { + thisLength = (dashAngle + dashRemaining <= endAngle) ? + dashRemaining : endAngle - dashAngle; + if (arcType == VERTICAL) { + xarc.y = dashAngle; + xarc.height = thisLength; + } else { + xarc.x = dashAngle; + xarc.width = thisLength; + } + dashAngle += thisLength; + dashRemaining -= thisLength; + } + if (iphase == 0 || isDoubleDash) { + if (arcType == OTHER) { + xarc = parcs[i]; + spanAngle = prevDashAngle; + if (spanAngle < 0) + spanAngle = FULLCIRCLE - (-spanAngle) % FULLCIRCLE; + if (spanAngle >= FULLCIRCLE) + spanAngle = spanAngle % FULLCIRCLE; + xarc.angle1 = spanAngle; + spanAngle = dashAngle - prevDashAngle; + if (backwards) { + if (dashAngle > prevDashAngle) + spanAngle = - FULLCIRCLE + spanAngle; + } else { + if (dashAngle < prevDashAngle) + spanAngle = FULLCIRCLE + spanAngle; + } + if (spanAngle > FULLCIRCLE) + spanAngle = FULLCIRCLE; + if (spanAngle < -FULLCIRCLE) + spanAngle = -FULLCIRCLE; + xarc.angle2 = spanAngle; + } + arc = addArc (&arcs[iphase].arcs, &arcs[iphase].narcs, + &arcSize[iphase], &xarc); + if (!arc) + goto arcfail; + /* + * cap each end of an on/off dash + */ + if (!isDoubleDash) { + if (prevDashAngle != startAngle) { + addCap (&arcs[iphase].caps, + &arcs[iphase].ncaps, + &capSize[iphase], RIGHT_END, + arc - arcs[iphase].arcs); + + } + if (dashAngle != endAngle) { + addCap (&arcs[iphase].caps, + &arcs[iphase].ncaps, + &capSize[iphase], LEFT_END, + arc - arcs[iphase].arcs); + } + } + arc->cap = arcs[iphase].ncaps; + arc->join = arcs[iphase].njoins; + arc->render = 0; + arc->selfJoin = 0; + if (dashAngle == endAngle) + arc->selfJoin = selfJoin; + } + prevphase = iphase; + if (dashRemaining <= 0) { + ++iDash; + if (iDash == pGC->numInDashList) + iDash = 0; + iphase = iphase ? 0:1; + dashRemaining = pGC->dash[iDash]; + } + } + /* + * make sure a place exists for the position data when + * drawing a zero-length arc + */ + if (startAngle == endAngle) { + prevphase = iphase; + if (!isDoubleDash && iphase == 1) + prevphase = 0; + arc = addArc (&arcs[prevphase].arcs, &arcs[prevphase].narcs, + &arcSize[prevphase], &parcs[i]); + if (!arc) + goto arcfail; + arc->join = arcs[prevphase].njoins; + arc->cap = arcs[prevphase].ncaps; + arc->selfJoin = data[i].selfJoin; + } + } else { + arc = addArc (&arcs[iphase].arcs, &arcs[iphase].narcs, + &arcSize[iphase], &parcs[i]); + if (!arc) + goto arcfail; + arc->join = arcs[iphase].njoins; + arc->cap = arcs[iphase].ncaps; + arc->selfJoin = data[i].selfJoin; + prevphase = iphase; + } + if (prevphase == 0 || isDoubleDash) + k = arcs[prevphase].narcs - 1; + if (iphase == 0 || isDoubleDash) + nextk = arcs[iphase].narcs; + if (nexti == start) { + nextk = 0; + if (isDashed) { + iDash = iDashStart; + iphase = iphaseStart; + dashRemaining = dashRemainingStart; + } + } + arcsJoin = narcs > 1 && i != j && + ISEQUAL (data[i].x1, data[j].x0) && + ISEQUAL (data[i].y1, data[j].y0) && + !data[i].selfJoin && !data[j].selfJoin; + if (arc) + { + if (arcsJoin) + arc->render = 0; + else + arc->render = 1; + } + if (arcsJoin && + (prevphase == 0 || isDoubleDash) && + (iphase == 0 || isDoubleDash)) + { + joinphase = iphase; + if (isDoubleDash) { + if (nexti == start) + joinphase = iphaseStart; + /* + * if the join is right at the dash, + * draw the join in foreground + * This is because the foreground + * arcs are computed second, the results + * of which are needed to draw the join + */ + if (joinphase != prevphase) + joinphase = 0; + } + if (joinphase == 0 || isDoubleDash) { + addJoin (&arcs[joinphase].joins, + &arcs[joinphase].njoins, + &joinSize[joinphase], + LEFT_END, k, prevphase, + RIGHT_END, nextk, iphase); + arc->join = arcs[prevphase].njoins; + } + } else { + /* + * cap the left end of this arc + * unless it joins itself + */ + if ((prevphase == 0 || isDoubleDash) && + !arc->selfJoin) + { + addCap (&arcs[prevphase].caps, &arcs[prevphase].ncaps, + &capSize[prevphase], LEFT_END, k); + arc->cap = arcs[prevphase].ncaps; + } + if (isDashed && !arcsJoin) { + iDash = iDashStart; + iphase = iphaseStart; + dashRemaining = dashRemainingStart; + } + nextk = arcs[iphase].narcs; + if (nexti == start) { + nextk = 0; + iDash = iDashStart; + iphase = iphaseStart; + dashRemaining = dashRemainingStart; + } + /* + * cap the right end of the next arc. If the + * next arc is actually the first arc, only + * cap it if it joins with this arc. This + * case will occur when the final dash segment + * of an on/off dash is off. Of course, this + * cap will be drawn at a strange time, but that + * hardly matters... + */ + if ((iphase == 0 || isDoubleDash) && + (nexti != start || (arcsJoin && isDashed))) + addCap (&arcs[iphase].caps, &arcs[iphase].ncaps, + &capSize[iphase], RIGHT_END, nextk); + } + i = nexti; + if (i == start) + break; + } + /* + * make sure the last section is rendered + */ + for (iphase = 0; iphase < (isDoubleDash ? 2 : 1); iphase++) + if (arcs[iphase].narcs > 0) { + arcs[iphase].arcs[arcs[iphase].narcs-1].render = 1; + arcs[iphase].arcs[arcs[iphase].narcs-1].join = + arcs[iphase].njoins; + arcs[iphase].arcs[arcs[iphase].narcs-1].cap = + arcs[iphase].ncaps; + } + xfree(data); + return arcs; +arcfail: + miFreeArcs(arcs, pGC); + xfree(data); + return NULL; +} + +static double +angleToLength ( + int angle, + dashMap *map) +{ + double len, excesslen, sidelen = map->map[DASH_MAP_SIZE - 1], totallen; + int di; + int excess; + Bool oddSide = FALSE; + + totallen = 0; + if (angle >= 0) { + while (angle >= 90 * 64) { + angle -= 90 * 64; + totallen += sidelen; + oddSide = !oddSide; + } + } else { + while (angle < 0) { + angle += 90 * 64; + totallen -= sidelen; + oddSide = !oddSide; + } + } + if (oddSide) + angle = 90 * 64 - angle; + + di = xAngleToDashIndex (angle); + excess = angle - dashIndexToXAngle (di); + + len = map->map[di]; + /* + * linearly interpolate between this point and the next + */ + if (excess > 0) { + excesslen = (map->map[di + 1] - map->map[di]) * + ((double) excess) / dashXAngleStep; + len += excesslen; + } + if (oddSide) + totallen += (sidelen - len); + else + totallen += len; + return totallen; +} + +/* + * len is along the arc, but may be more than one rotation + */ + +static int +lengthToAngle ( + double len, + dashMap *map) +{ + double sidelen = map->map[DASH_MAP_SIZE - 1]; + int angle, angleexcess; + Bool oddSide = FALSE; + int a0, a1, a; + + angle = 0; + /* + * step around the ellipse, subtracting sidelens and + * adding 90 degrees. oddSide will tell if the + * map should be interpolated in reverse + */ + if (len >= 0) { + if (sidelen == 0) + return 2 * FULLCIRCLE; /* infinity */ + while (len >= sidelen) { + angle += 90 * 64; + len -= sidelen; + oddSide = !oddSide; + } + } else { + if (sidelen == 0) + return -2 * FULLCIRCLE; /* infinity */ + while (len < 0) { + angle -= 90 * 64; + len += sidelen; + oddSide = !oddSide; + } + } + if (oddSide) + len = sidelen - len; + a0 = 0; + a1 = DASH_MAP_SIZE - 1; + /* + * binary search for the closest pre-computed length + */ + while (a1 - a0 > 1) { + a = (a0 + a1) / 2; + if (len > map->map[a]) + a0 = a; + else + a1 = a; + } + angleexcess = dashIndexToXAngle (a0); + /* + * linearly interpolate to the next point + */ + angleexcess += (len - map->map[a0]) / + (map->map[a0+1] - map->map[a0]) * dashXAngleStep; + if (oddSide) + angle += (90 * 64) - angleexcess; + else + angle += angleexcess; + return angle; +} + +/* + * compute the angle of an ellipse which cooresponds to + * the given path length. Note that the correct solution + * to this problem is an eliptic integral, we'll punt and + * approximate (it's only for dashes anyway). This + * approximation uses a polygon. + * + * The remaining portion of len is stored in *lenp - + * this will be negative if the arc extends beyond + * len and positive if len extends beyond the arc. + */ + +static int +computeAngleFromPath ( + int startAngle, + int endAngle, /* normalized absolute angles in *64 degrees */ + dashMap *map, + int *lenp, + int backwards) +{ + int a0, a1, a; + double len0; + int len; + + a0 = startAngle; + a1 = endAngle; + len = *lenp; + if (backwards) { + /* + * flip the problem around to always be + * forwards + */ + a0 = FULLCIRCLE - a0; + a1 = FULLCIRCLE - a1; + } + if (a1 < a0) + a1 += FULLCIRCLE; + len0 = angleToLength (a0, map); + a = lengthToAngle (len0 + len, map); + if (a > a1) { + a = a1; + len -= angleToLength (a1, map) - len0; + } else + len = 0; + if (backwards) + a = FULLCIRCLE - a; + *lenp = len; + return a; +} + +/* + * scan convert wide arcs. + */ + +/* + * draw zero width/height arcs + */ + +static void +drawZeroArc ( + DrawablePtr pDraw, + GCPtr pGC, + xArc *tarc, + int lw, + miArcFacePtr left, + miArcFacePtr right) +{ + double x0 = 0.0, y0 = 0.0, x1 = 0.0, y1 = 0.0, w, h, x, y; + double xmax, ymax, xmin, ymin; + int a0, a1; + double a, startAngle, endAngle; + double l, lx, ly; + + l = lw / 2.0; + a0 = tarc->angle1; + a1 = tarc->angle2; + if (a1 > FULLCIRCLE) + a1 = FULLCIRCLE; + else if (a1 < -FULLCIRCLE) + a1 = -FULLCIRCLE; + w = (double)tarc->width / 2.0; + h = (double)tarc->height / 2.0; + /* + * play in X coordinates right away + */ + startAngle = - ((double) a0 / 64.0); + endAngle = - ((double) (a0 + a1) / 64.0); + + xmax = -w; + xmin = w; + ymax = -h; + ymin = h; + a = startAngle; + for (;;) + { + x = w * miDcos(a); + y = h * miDsin(a); + if (a == startAngle) + { + x0 = x; + y0 = y; + } + if (a == endAngle) + { + x1 = x; + y1 = y; + } + if (x > xmax) + xmax = x; + if (x < xmin) + xmin = x; + if (y > ymax) + ymax = y; + if (y < ymin) + ymin = y; + if (a == endAngle) + break; + if (a1 < 0) /* clockwise */ + { + if (floor (a / 90.0) == floor (endAngle / 90.0)) + a = endAngle; + else + a = 90 * (floor (a/90.0) + 1); + } + else + { + if (ceil (a / 90.0) == ceil (endAngle / 90.0)) + a = endAngle; + else + a = 90 * (ceil (a/90.0) - 1); + } + } + lx = ly = l; + if ((x1 - x0) + (y1 - y0) < 0) + lx = ly = -l; + if (h) + { + ly = 0.0; + lx = -lx; + } + else + lx = 0.0; + if (right) + { + right->center.x = x0; + right->center.y = y0; + right->clock.x = x0 - lx; + right->clock.y = y0 - ly; + right->counterClock.x = x0 + lx; + right->counterClock.y = y0 + ly; + } + if (left) + { + left->center.x = x1; + left->center.y = y1; + left->clock.x = x1 + lx; + left->clock.y = y1 + ly; + left->counterClock.x = x1 - lx; + left->counterClock.y = y1 - ly; + } + + x0 = xmin; + x1 = xmax; + y0 = ymin; + y1 = ymax; + if (ymin != y1) { + xmin = -l; + xmax = l; + } else { + ymin = -l; + ymax = l; + } + if (xmax != xmin && ymax != ymin) { + int minx, maxx, miny, maxy; + xRectangle rect; + + minx = ICEIL (xmin + w) + tarc->x; + maxx = ICEIL (xmax + w) + tarc->x; + miny = ICEIL (ymin + h) + tarc->y; + maxy = ICEIL (ymax + h) + tarc->y; + rect.x = minx; + rect.y = miny; + rect.width = maxx - minx; + rect.height = maxy - miny; + (*pGC->ops->PolyFillRect) (pDraw, pGC, 1, &rect); + } +} + +/* + * this computes the ellipse y value associated with the + * bottom of the tail. + */ + +static void +tailEllipseY ( + struct arc_def *def, + struct accelerators *acc) +{ + double t; + + acc->tail_y = 0.0; + if (def->w == def->h) + return; + t = def->l * def->w; + if (def->w > def->h) { + if (t < acc->h2) + return; + } else { + if (t > acc->h2) + return; + } + t = 2.0 * def->h * t; + t = (CUBED_ROOT_4 * acc->h2 - cbrt(t * t)) / acc->h2mw2; + if (t > 0.0) + acc->tail_y = def->h / CUBED_ROOT_2 * sqrt(t); +} + +/* + * inverse functions -- compute edge coordinates + * from the ellipse + */ + +static double +outerXfromXY ( + double x, + double y, + struct arc_def *def, + struct accelerators *acc) +{ + return x + (x * acc->h2l) / sqrt (x*x * acc->h4 + y*y * acc->w4); +} + +static double +outerYfromXY ( + double x, + double y, + struct arc_def *def, + struct accelerators *acc) +{ + return y + (y * acc->w2l) / sqrt (x*x * acc->h4 + y*y * acc->w4); +} + +static double +innerXfromXY ( + double x, + double y, + struct arc_def *def, + struct accelerators *acc) +{ + return x - (x * acc->h2l) / sqrt (x*x * acc->h4 + y*y * acc->w4); +} + +static double +innerYfromXY ( + double x, + double y, + struct arc_def *def, + struct accelerators *acc) +{ + return y - (y * acc->w2l) / sqrt (x*x * acc->h4 + y*y * acc->w4); +} + +static double +innerYfromY ( + double y, + struct arc_def *def, + struct accelerators *acc) +{ + double x; + + x = (def->w / def->h) * sqrt (acc->h2 - y*y); + + return y - (y * acc->w2l) / sqrt (x*x * acc->h4 + y*y * acc->w4); +} + +static void +computeLine ( + double x1, + double y1, + double x2, + double y2, + struct line *line) +{ + if (y1 == y2) + line->valid = 0; + else { + line->m = (x1 - x2) / (y1 - y2); + line->b = x1 - y1 * line->m; + line->valid = 1; + } +} + +/* + * compute various accelerators for an ellipse. These + * are simply values that are used repeatedly in + * the computations + */ + +static void +computeAcc ( + xArc *tarc, + int lw, + struct arc_def *def, + struct accelerators *acc) +{ + def->w = ((double) tarc->width) / 2.0; + def->h = ((double) tarc->height) / 2.0; + def->l = ((double) lw) / 2.0; + acc->h2 = def->h * def->h; + acc->w2 = def->w * def->w; + acc->h4 = acc->h2 * acc->h2; + acc->w4 = acc->w2 * acc->w2; + acc->h2l = acc->h2 * def->l; + acc->w2l = acc->w2 * def->l; + acc->h2mw2 = acc->h2 - acc->w2; + acc->fromIntX = (tarc->width & 1) ? 0.5 : 0.0; + acc->fromIntY = (tarc->height & 1) ? 0.5 : 0.0; + acc->xorg = tarc->x + (tarc->width >> 1); + acc->yorgu = tarc->y + (tarc->height >> 1); + acc->yorgl = acc->yorgu + (tarc->height & 1); + tailEllipseY (def, acc); +} + +/* + * compute y value bounds of various portions of the arc, + * the outer edge, the ellipse and the inner edge. + */ + +static void +computeBound ( + struct arc_def *def, + struct arc_bound *bound, + struct accelerators *acc, + miArcFacePtr right, + miArcFacePtr left) +{ + double t; + double innerTaily; + double tail_y; + struct bound innerx, outerx; + struct bound ellipsex; + + bound->ellipse.min = Dsin (def->a0) * def->h; + bound->ellipse.max = Dsin (def->a1) * def->h; + if (def->a0 == 45 && def->w == def->h) + ellipsex.min = bound->ellipse.min; + else + ellipsex.min = Dcos (def->a0) * def->w; + if (def->a1 == 45 && def->w == def->h) + ellipsex.max = bound->ellipse.max; + else + ellipsex.max = Dcos (def->a1) * def->w; + bound->outer.min = outerYfromXY (ellipsex.min, bound->ellipse.min, def, acc); + bound->outer.max = outerYfromXY (ellipsex.max, bound->ellipse.max, def, acc); + bound->inner.min = innerYfromXY (ellipsex.min, bound->ellipse.min, def, acc); + bound->inner.max = innerYfromXY (ellipsex.max, bound->ellipse.max, def, acc); + + outerx.min = outerXfromXY (ellipsex.min, bound->ellipse.min, def, acc); + outerx.max = outerXfromXY (ellipsex.max, bound->ellipse.max, def, acc); + innerx.min = innerXfromXY (ellipsex.min, bound->ellipse.min, def, acc); + innerx.max = innerXfromXY (ellipsex.max, bound->ellipse.max, def, acc); + + /* + * save the line end points for the + * cap code to use. Careful here, these are + * in cartesean coordinates (y increasing upwards) + * while the cap code uses inverted coordinates + * (y increasing downwards) + */ + + if (right) { + right->counterClock.y = bound->outer.min; + right->counterClock.x = outerx.min; + right->center.y = bound->ellipse.min; + right->center.x = ellipsex.min; + right->clock.y = bound->inner.min; + right->clock.x = innerx.min; + } + + if (left) { + left->clock.y = bound->outer.max; + left->clock.x = outerx.max; + left->center.y = bound->ellipse.max; + left->center.x = ellipsex.max; + left->counterClock.y = bound->inner.max; + left->counterClock.x = innerx.max; + } + + bound->left.min = bound->inner.max; + bound->left.max = bound->outer.max; + bound->right.min = bound->inner.min; + bound->right.max = bound->outer.min; + + computeLine (innerx.min, bound->inner.min, outerx.min, bound->outer.min, + &acc->right); + computeLine (innerx.max, bound->inner.max, outerx.max, bound->outer.max, + &acc->left); + + if (bound->inner.min > bound->inner.max) { + t = bound->inner.min; + bound->inner.min = bound->inner.max; + bound->inner.max = t; + } + tail_y = acc->tail_y; + if (tail_y > bound->ellipse.max) + tail_y = bound->ellipse.max; + else if (tail_y < bound->ellipse.min) + tail_y = bound->ellipse.min; + innerTaily = innerYfromY (tail_y, def, acc); + if (bound->inner.min > innerTaily) + bound->inner.min = innerTaily; + if (bound->inner.max < innerTaily) + bound->inner.max = innerTaily; + bound->inneri.min = ICEIL(bound->inner.min - acc->fromIntY); + bound->inneri.max = floor(bound->inner.max - acc->fromIntY); + bound->outeri.min = ICEIL(bound->outer.min - acc->fromIntY); + bound->outeri.max = floor(bound->outer.max - acc->fromIntY); +} + +/* + * this section computes the x value of the span at y + * intersected with the specified face of the ellipse. + * + * this is the min/max X value over the set of normal + * lines to the entire ellipse, the equation of the + * normal lines is: + * + * ellipse_x h^2 h^2 + * x = ------------ y + ellipse_x (1 - --- ) + * ellipse_y w^2 w^2 + * + * compute the derivative with-respect-to ellipse_y and solve + * for zero: + * + * (w^2 - h^2) ellipse_y^3 + h^4 y + * 0 = - ---------------------------------- + * h w ellipse_y^2 sqrt (h^2 - ellipse_y^2) + * + * ( h^4 y ) + * ellipse_y = ( ---------- ) ^ (1/3) + * ( (h^2 - w^2) ) + * + * The other two solutions to the equation are imaginary. + * + * This gives the position on the ellipse which generates + * the normal with the largest/smallest x intersection point. + * + * Now compute the second derivative to check whether + * the intersection is a minimum or maximum: + * + * h (y0^3 (w^2 - h^2) + h^2 y (3y0^2 - 2h^2)) + * - ------------------------------------------- + * w y0^3 (sqrt (h^2 - y^2)) ^ 3 + * + * as we only care about the sign, + * + * - (y0^3 (w^2 - h^2) + h^2 y (3y0^2 - 2h^2)) + * + * or (to use accelerators), + * + * y0^3 (h^2 - w^2) - h^2 y (3y0^2 - 2h^2) + * + */ + +/* + * computes the position on the ellipse whose normal line + * intersects the given scan line maximally + */ + +static double +hookEllipseY ( + double scan_y, + struct arc_bound *bound, + struct accelerators *acc, + int left) +{ + double ret; + + if (acc->h2mw2 == 0) { + if ( (scan_y > 0 && !left) || (scan_y < 0 && left) ) + return bound->ellipse.min; + return bound->ellipse.max; + } + ret = (acc->h4 * scan_y) / (acc->h2mw2); + if (ret >= 0) + return cbrt (ret); + else + return -cbrt (-ret); +} + +/* + * computes the X value of the intersection of the + * given scan line with the right side of the lower hook + */ + +static double +hookX ( + double scan_y, + struct arc_def *def, + struct arc_bound *bound, + struct accelerators *acc, + int left) +{ + double ellipse_y, x; + double maxMin; + + if (def->w != def->h) { + ellipse_y = hookEllipseY (scan_y, bound, acc, left); + if (boundedLe (ellipse_y, bound->ellipse)) { + /* + * compute the value of the second + * derivative + */ + maxMin = ellipse_y*ellipse_y*ellipse_y * acc->h2mw2 - + acc->h2 * scan_y * (3 * ellipse_y*ellipse_y - 2*acc->h2); + if ((left && maxMin > 0) || (!left && maxMin < 0)) { + if (ellipse_y == 0) + return def->w + left ? -def->l : def->l; + x = (acc->h2 * scan_y - ellipse_y * acc->h2mw2) * + sqrt (acc->h2 - ellipse_y * ellipse_y) / + (def->h * def->w * ellipse_y); + return x; + } + } + } + if (left) { + if (acc->left.valid && boundedLe (scan_y, bound->left)) { + x = intersectLine (scan_y, acc->left); + } else { + if (acc->right.valid) + x = intersectLine (scan_y, acc->right); + else + x = def->w - def->l; + } + } else { + if (acc->right.valid && boundedLe (scan_y, bound->right)) { + x = intersectLine (scan_y, acc->right); + } else { + if (acc->left.valid) + x = intersectLine (scan_y, acc->left); + else + x = def->w - def->l; + } + } + return x; +} + +/* + * generate the set of spans with + * the given y coordinate + */ + +static void +arcSpan ( + int y, + int lx, + int lw, + int rx, + int rw, + struct arc_def *def, + struct arc_bound *bounds, + struct accelerators *acc, + int mask) +{ + int linx, loutx, rinx, routx; + double x, altx; + + if (boundedLe (y, bounds->inneri)) { + linx = -(lx + lw); + rinx = rx; + } else { + /* + * intersection with left face + */ + x = hookX (y + acc->fromIntY, def, bounds, acc, 1); + if (acc->right.valid && + boundedLe (y + acc->fromIntY, bounds->right)) + { + altx = intersectLine (y + acc->fromIntY, acc->right); + if (altx < x) + x = altx; + } + linx = -ICEIL(acc->fromIntX - x); + rinx = ICEIL(acc->fromIntX + x); + } + if (boundedLe (y, bounds->outeri)) { + loutx = -lx; + routx = rx + rw; + } else { + /* + * intersection with right face + */ + x = hookX (y + acc->fromIntY, def, bounds, acc, 0); + if (acc->left.valid && + boundedLe (y + acc->fromIntY, bounds->left)) + { + altx = x; + x = intersectLine (y + acc->fromIntY, acc->left); + if (x < altx) + x = altx; + } + loutx = -ICEIL(acc->fromIntX - x); + routx = ICEIL(acc->fromIntX + x); + } + if (routx > rinx) { + if (mask & 1) + newFinalSpan (acc->yorgu - y, + acc->xorg + rinx, acc->xorg + routx); + if (mask & 8) + newFinalSpan (acc->yorgl + y, + acc->xorg + rinx, acc->xorg + routx); + } + if (loutx > linx) { + if (mask & 2) + newFinalSpan (acc->yorgu - y, + acc->xorg - loutx, acc->xorg - linx); + if (mask & 4) + newFinalSpan (acc->yorgl + y, + acc->xorg - loutx, acc->xorg - linx); + } +} + +static void +arcSpan0 ( + int lx, + int lw, + int rx, + int rw, + struct arc_def *def, + struct arc_bound *bounds, + struct accelerators *acc, + int mask) +{ + double x; + + if (boundedLe (0, bounds->inneri) && + acc->left.valid && boundedLe (0, bounds->left) && + acc->left.b > 0) + { + x = def->w - def->l; + if (acc->left.b < x) + x = acc->left.b; + lw = ICEIL(acc->fromIntX - x) - lx; + rw += rx; + rx = ICEIL(acc->fromIntX + x); + rw -= rx; + } + arcSpan (0, lx, lw, rx, rw, def, bounds, acc, mask); +} + +static void +tailSpan ( + int y, + int lw, + int rw, + struct arc_def *def, + struct arc_bound *bounds, + struct accelerators *acc, + int mask) +{ + double yy, xalt, x, lx, rx; + int n; + + if (boundedLe(y, bounds->outeri)) + arcSpan (y, 0, lw, -rw, rw, def, bounds, acc, mask); + else if (def->w != def->h) { + yy = y + acc->fromIntY; + x = tailX(yy, def, bounds, acc); + if (yy == 0.0 && x == -rw - acc->fromIntX) + return; + if (acc->right.valid && boundedLe (yy, bounds->right)) { + rx = x; + lx = -x; + xalt = intersectLine (yy, acc->right); + if (xalt >= -rw - acc->fromIntX && xalt <= rx) + rx = xalt; + n = ICEIL(acc->fromIntX + lx); + if (lw > n) { + if (mask & 2) + newFinalSpan (acc->yorgu - y, + acc->xorg + n, acc->xorg + lw); + if (mask & 4) + newFinalSpan (acc->yorgl + y, + acc->xorg + n, acc->xorg + lw); + } + n = ICEIL(acc->fromIntX + rx); + if (n > -rw) { + if (mask & 1) + newFinalSpan (acc->yorgu - y, + acc->xorg - rw, acc->xorg + n); + if (mask & 8) + newFinalSpan (acc->yorgl + y, + acc->xorg - rw, acc->xorg + n); + } + } + arcSpan (y, + ICEIL(acc->fromIntX - x), 0, + ICEIL(acc->fromIntX + x), 0, + def, bounds, acc, mask); + } +} + +/* + * create whole arcs out of pieces. This code is + * very bad. + */ + +static struct finalSpan **finalSpans = NULL; +static int finalMiny = 0, finalMaxy = -1; +static int finalSize = 0; + +static int nspans = 0; /* total spans, not just y coords */ + +struct finalSpan { + struct finalSpan *next; + int min, max; /* x values */ +}; + +static struct finalSpan *freeFinalSpans, *tmpFinalSpan; + +# define allocFinalSpan() (freeFinalSpans ?\ + ((tmpFinalSpan = freeFinalSpans), \ + (freeFinalSpans = freeFinalSpans->next), \ + (tmpFinalSpan->next = 0), \ + tmpFinalSpan) : \ + realAllocSpan ()) + +# define SPAN_CHUNK_SIZE 128 + +struct finalSpanChunk { + struct finalSpan data[SPAN_CHUNK_SIZE]; + struct finalSpanChunk *next; +}; + +static struct finalSpanChunk *chunks; + +static struct finalSpan * +realAllocSpan (void) +{ + struct finalSpanChunk *newChunk; + struct finalSpan *span; + int i; + + newChunk = xalloc (sizeof (struct finalSpanChunk)); + if (!newChunk) + return (struct finalSpan *) NULL; + newChunk->next = chunks; + chunks = newChunk; + freeFinalSpans = span = newChunk->data + 1; + for (i = 1; i < SPAN_CHUNK_SIZE-1; i++) { + span->next = span+1; + span++; + } + span->next = 0; + span = newChunk->data; + span->next = 0; + return span; +} + +static void +disposeFinalSpans (void) +{ + struct finalSpanChunk *chunk, *next; + + for (chunk = chunks; chunk; chunk = next) { + next = chunk->next; + xfree (chunk); + } + chunks = 0; + freeFinalSpans = 0; + xfree(finalSpans); + finalSpans = 0; +} + +static void +fillSpans ( + DrawablePtr pDrawable, + GCPtr pGC) +{ + struct finalSpan *span; + DDXPointPtr xSpan; + int *xWidth; + int i; + struct finalSpan **f; + int spany; + DDXPointPtr xSpans; + int *xWidths; + + if (nspans == 0) + return; + xSpan = xSpans = xalloc (nspans * sizeof (DDXPointRec)); + xWidth = xWidths = xalloc (nspans * sizeof (int)); + if (xSpans && xWidths) + { + i = 0; + f = finalSpans; + for (spany = finalMiny; spany <= finalMaxy; spany++, f++) { + for (span = *f; span; span=span->next) { + if (span->max <= span->min) + continue; + xSpan->x = span->min; + xSpan->y = spany; + ++xSpan; + *xWidth++ = span->max - span->min; + ++i; + } + } + (*pGC->ops->FillSpans) (pDrawable, pGC, i, xSpans, xWidths, TRUE); + } + disposeFinalSpans (); + if (xSpans) + xfree (xSpans); + if (xWidths) + xfree (xWidths); + finalMiny = 0; + finalMaxy = -1; + finalSize = 0; + nspans = 0; +} + +# define SPAN_REALLOC 100 + +# define findSpan(y) ((finalMiny <= (y) && (y) <= finalMaxy) ? \ + &finalSpans[(y) - finalMiny] : \ + realFindSpan (y)) + +static struct finalSpan ** +realFindSpan (int y) +{ + struct finalSpan **newSpans; + int newSize, newMiny, newMaxy; + int change; + int i; + + if (y < finalMiny || y > finalMaxy) { + if (!finalSize) { + finalMiny = y; + finalMaxy = y - 1; + } + if (y < finalMiny) + change = finalMiny - y; + else + change = y - finalMaxy; + if (change >= SPAN_REALLOC) + change += SPAN_REALLOC; + else + change = SPAN_REALLOC; + newSize = finalSize + change; + newSpans = xalloc(newSize * sizeof (struct finalSpan *)); + if (!newSpans) + return NULL; + newMiny = finalMiny; + newMaxy = finalMaxy; + if (y < finalMiny) + newMiny = finalMiny - change; + else + newMaxy = finalMaxy + change; + if (finalSpans) { + memmove(((char *) newSpans) + (finalMiny-newMiny) * sizeof (struct finalSpan *), + (char *) finalSpans, + finalSize * sizeof (struct finalSpan *)); + xfree (finalSpans); + } + if ((i = finalMiny - newMiny) > 0) + bzero ((char *)newSpans, i * sizeof (struct finalSpan *)); + if ((i = newMaxy - finalMaxy) > 0) + bzero ((char *)(newSpans + newSize - i), + i * sizeof (struct finalSpan *)); + finalSpans = newSpans; + finalMaxy = newMaxy; + finalMiny = newMiny; + finalSize = newSize; + } + return &finalSpans[y - finalMiny]; +} + +static void +newFinalSpan ( + int y, + int xmin, + int xmax) +{ + struct finalSpan *x; + struct finalSpan **f; + struct finalSpan *oldx; + struct finalSpan *prev; + + f = findSpan (y); + if (!f) + return; + oldx = 0; + for (;;) { + prev = 0; + for (x = *f; x; x=x->next) { + if (x == oldx) { + prev = x; + continue; + } + if (x->min <= xmax && xmin <= x->max) { + if (oldx) { + oldx->min = min (x->min, xmin); + oldx->max = max (x->max, xmax); + if (prev) + prev->next = x->next; + else + *f = x->next; + --nspans; + } else { + x->min = min (x->min, xmin); + x->max = max (x->max, xmax); + oldx = x; + } + xmin = oldx->min; + xmax = oldx->max; + break; + } + prev = x; + } + if (!x) + break; + } + if (!oldx) { + x = allocFinalSpan (); + if (x) + { + x->min = xmin; + x->max = xmax; + x->next = *f; + *f = x; + ++nspans; + } + } +} + +static void +mirrorSppPoint ( + int quadrant, + SppPointPtr sppPoint) +{ + switch (quadrant) { + case 0: + break; + case 1: + sppPoint->x = -sppPoint->x; + break; + case 2: + sppPoint->x = -sppPoint->x; + sppPoint->y = -sppPoint->y; + break; + case 3: + sppPoint->y = -sppPoint->y; + break; + } + /* + * and translate to X coordinate system + */ + sppPoint->y = -sppPoint->y; +} + +/* + * split an arc into pieces which are scan-converted + * in the first-quadrant and mirrored into position. + * This is necessary as the scan-conversion code can + * only deal with arcs completely contained in the + * first quadrant. + */ + +static void +drawArc ( + xArc *tarc, + int l, + int a0, + int a1, + miArcFacePtr right, + miArcFacePtr left) /* save end line points */ +{ + struct arc_def def; + struct accelerators acc; + int startq, endq, curq; + int rightq, leftq = 0, righta = 0, lefta = 0; + miArcFacePtr passRight, passLeft; + int q0 = 0, q1 = 0, mask; + struct band { + int a0, a1; + int mask; + } band[5], sweep[20]; + int bandno, sweepno; + int i, j; + int flipRight = 0, flipLeft = 0; + int copyEnd = 0; + miArcSpanData *spdata; + + spdata = miComputeWideEllipse(l, tarc); + if (!spdata) + return; + + if (a1 < a0) + a1 += 360 * 64; + startq = a0 / (90 * 64); + if (a0 == a1) + endq = startq; + else + endq = (a1-1) / (90 * 64); + bandno = 0; + curq = startq; + rightq = -1; + for (;;) { + switch (curq) { + case 0: + if (a0 > 90 * 64) + q0 = 0; + else + q0 = a0; + if (a1 < 360 * 64) + q1 = min (a1, 90 * 64); + else + q1 = 90 * 64; + if (curq == startq && a0 == q0 && rightq < 0) { + righta = q0; + rightq = curq; + } + if (curq == endq && a1 == q1) { + lefta = q1; + leftq = curq; + } + break; + case 1: + if (a1 < 90 * 64) + q0 = 0; + else + q0 = 180 * 64 - min (a1, 180 * 64); + if (a0 > 180 * 64) + q1 = 90 * 64; + else + q1 = 180 * 64 - max (a0, 90 * 64); + if (curq == startq && 180 * 64 - a0 == q1) { + righta = q1; + rightq = curq; + } + if (curq == endq && 180 * 64 - a1 == q0) { + lefta = q0; + leftq = curq; + } + break; + case 2: + if (a0 > 270 * 64) + q0 = 0; + else + q0 = max (a0, 180 * 64) - 180 * 64; + if (a1 < 180 * 64) + q1 = 90 * 64; + else + q1 = min (a1, 270 * 64) - 180 * 64; + if (curq == startq && a0 - 180*64 == q0) { + righta = q0; + rightq = curq; + } + if (curq == endq && a1 - 180 * 64 == q1) { + lefta = q1; + leftq = curq; + } + break; + case 3: + if (a1 < 270 * 64) + q0 = 0; + else + q0 = 360 * 64 - min (a1, 360 * 64); + q1 = 360 * 64 - max (a0, 270 * 64); + if (curq == startq && 360 * 64 - a0 == q1) { + righta = q1; + rightq = curq; + } + if (curq == endq && 360 * 64 - a1 == q0) { + lefta = q0; + leftq = curq; + } + break; + } + band[bandno].a0 = q0; + band[bandno].a1 = q1; + band[bandno].mask = 1 << curq; + bandno++; + if (curq == endq) + break; + curq++; + if (curq == 4) { + a0 = 0; + a1 -= 360 * 64; + curq = 0; + endq -= 4; + } + } + sweepno = 0; + for (;;) { + q0 = 90 * 64; + mask = 0; + /* + * find left-most point + */ + for (i = 0; i < bandno; i++) + if (band[i].a0 <= q0) { + q0 = band[i].a0; + q1 = band[i].a1; + mask = band[i].mask; + } + if (!mask) + break; + /* + * locate next point of change + */ + for (i = 0; i < bandno; i++) + if (!(mask & band[i].mask)) { + if (band[i].a0 == q0) { + if (band[i].a1 < q1) + q1 = band[i].a1; + mask |= band[i].mask; + } else if (band[i].a0 < q1) + q1 = band[i].a0; + } + /* + * create a new sweep + */ + sweep[sweepno].a0 = q0; + sweep[sweepno].a1 = q1; + sweep[sweepno].mask = mask; + sweepno++; + /* + * subtract the sweep from the affected bands + */ + for (i = 0; i < bandno; i++) + if (band[i].a0 == q0) { + band[i].a0 = q1; + /* + * check if this band is empty + */ + if (band[i].a0 == band[i].a1) + band[i].a1 = band[i].a0 = 90 * 64 + 1; + } + } + computeAcc (tarc, l, &def, &acc); + for (j = 0; j < sweepno; j++) { + mask = sweep[j].mask; + passRight = passLeft = 0; + if (mask & (1 << rightq)) { + if (sweep[j].a0 == righta) + passRight = right; + else if (sweep[j].a1 == righta) { + passLeft = right; + flipRight = 1; + } + } + if (mask & (1 << leftq)) { + if (sweep[j].a1 == lefta) + { + if (passLeft) + copyEnd = 1; + passLeft = left; + } + else if (sweep[j].a0 == lefta) { + if (passRight) + copyEnd = 1; + passRight = left; + flipLeft = 1; + } + } + drawQuadrant (&def, &acc, sweep[j].a0, sweep[j].a1, mask, + passRight, passLeft, spdata); + } + /* + * when copyEnd is set, both ends of the arc were computed + * at the same time; drawQuadrant only takes one end though, + * so the left end will be the only one holding the data. Copy + * it from there. + */ + if (copyEnd) + *right = *left; + /* + * mirror the coordinates generated for the + * faces of the arc + */ + if (right) { + mirrorSppPoint (rightq, &right->clock); + mirrorSppPoint (rightq, &right->center); + mirrorSppPoint (rightq, &right->counterClock); + if (flipRight) { + SppPointRec temp; + + temp = right->clock; + right->clock = right->counterClock; + right->counterClock = temp; + } + } + if (left) { + mirrorSppPoint (leftq, &left->counterClock); + mirrorSppPoint (leftq, &left->center); + mirrorSppPoint (leftq, &left->clock); + if (flipLeft) { + SppPointRec temp; + + temp = left->clock; + left->clock = left->counterClock; + left->counterClock = temp; + } + } + xfree(spdata); +} + +static void +drawQuadrant ( + struct arc_def *def, + struct accelerators *acc, + int a0, + int a1, + int mask, + miArcFacePtr right, + miArcFacePtr left, + miArcSpanData *spdata) +{ + struct arc_bound bound; + double yy, x, xalt; + int y, miny, maxy; + int n; + miArcSpan *span; + + def->a0 = ((double) a0) / 64.0; + def->a1 = ((double) a1) / 64.0; + computeBound (def, &bound, acc, right, left); + yy = bound.inner.min; + if (bound.outer.min < yy) + yy = bound.outer.min; + miny = ICEIL(yy - acc->fromIntY); + yy = bound.inner.max; + if (bound.outer.max > yy) + yy = bound.outer.max; + maxy = floor(yy - acc->fromIntY); + y = spdata->k; + span = spdata->spans; + if (spdata->top) + { + if (a1 == 90 * 64 && (mask & 1)) + newFinalSpan (acc->yorgu - y - 1, acc->xorg, acc->xorg + 1); + span++; + } + for (n = spdata->count1; --n >= 0; ) + { + if (y < miny) + return; + if (y <= maxy) { + arcSpan (y, + span->lx, -span->lx, 0, span->lx + span->lw, + def, &bound, acc, mask); + if (span->rw + span->rx) + tailSpan (y, -span->rw, -span->rx, def, &bound, acc, mask); + } + y--; + span++; + } + if (y < miny) + return; + if (spdata->hole) + { + if (y <= maxy) + arcSpan (y, 0, 0, 0, 1, def, &bound, acc, mask & 0xc); + } + for (n = spdata->count2; --n >= 0; ) + { + if (y < miny) + return; + if (y <= maxy) + arcSpan (y, span->lx, span->lw, span->rx, span->rw, + def, &bound, acc, mask); + y--; + span++; + } + if (spdata->bot && miny <= y && y <= maxy) + { + n = mask; + if (y == miny) + n &= 0xc; + if (span->rw <= 0) { + arcSpan0 (span->lx, -span->lx, 0, span->lx + span->lw, + def, &bound, acc, n); + if (span->rw + span->rx) + tailSpan (y, -span->rw, -span->rx, def, &bound, acc, n); + } + else + arcSpan0 (span->lx, span->lw, span->rx, span->rw, + def, &bound, acc, n); + y--; + } + while (y >= miny) { + yy = y + acc->fromIntY; + if (def->w == def->h) { + xalt = def->w - def->l; + x = -sqrt(xalt * xalt - yy * yy); + } else { + x = tailX(yy, def, &bound, acc); + if (acc->left.valid && boundedLe (yy, bound.left)) { + xalt = intersectLine (yy, acc->left); + if (xalt < x) + x = xalt; + } + if (acc->right.valid && boundedLe (yy, bound.right)) { + xalt = intersectLine (yy, acc->right); + if (xalt < x) + x = xalt; + } + } + arcSpan (y, + ICEIL(acc->fromIntX - x), 0, + ICEIL(acc->fromIntX + x), 0, + def, &bound, acc, mask); + y--; + } +} -- cgit v1.2.3