diff options
author | marha <marha@users.sourceforge.net> | 2010-12-28 16:10:20 +0000 |
---|---|---|
committer | marha <marha@users.sourceforge.net> | 2010-12-28 16:10:20 +0000 |
commit | 807c6931fe683fd844ceec1b023232181e6aae03 (patch) | |
tree | 1a131ed95fe2200d0ad33da8f7755a7ed2364adc /mesalib/src/mesa/swrast/s_aaline.c | |
parent | 973099dda7e49e5abe29819a7124b3b1e7bd8b92 (diff) | |
download | vcxsrv-807c6931fe683fd844ceec1b023232181e6aae03.tar.gz vcxsrv-807c6931fe683fd844ceec1b023232181e6aae03.tar.bz2 vcxsrv-807c6931fe683fd844ceec1b023232181e6aae03.zip |
xserver and mesa git update 28-12-2010
Diffstat (limited to 'mesalib/src/mesa/swrast/s_aaline.c')
-rw-r--r-- | mesalib/src/mesa/swrast/s_aaline.c | 984 |
1 files changed, 492 insertions, 492 deletions
diff --git a/mesalib/src/mesa/swrast/s_aaline.c b/mesalib/src/mesa/swrast/s_aaline.c index 6ba4604e6..be817f326 100644 --- a/mesalib/src/mesa/swrast/s_aaline.c +++ b/mesalib/src/mesa/swrast/s_aaline.c @@ -1,492 +1,492 @@ -/* - * Mesa 3-D graphics library - * Version: 6.5.3 - * - * Copyright (C) 1999-2007 Brian Paul All Rights Reserved. - * - * Permission is hereby granted, free of charge, to any person obtaining a - * copy of this software and associated documentation files (the "Software"), - * to deal in the Software without restriction, including without limitation - * the rights to use, copy, modify, merge, publish, distribute, sublicense, - * and/or sell copies of the Software, and to permit persons to whom the - * Software is furnished to do so, subject to the following conditions: - * - * 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 - * BRIAN PAUL 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. - */ - - -#include "main/glheader.h" -#include "main/imports.h" -#include "main/macros.h" -#include "main/mtypes.h" -#include "swrast/s_aaline.h" -#include "swrast/s_context.h" -#include "swrast/s_span.h" -#include "swrast/swrast.h" - - -#define SUB_PIXEL 4 - - -/* - * Info about the AA line we're rendering - */ -struct LineInfo -{ - GLfloat x0, y0; /* start */ - GLfloat x1, y1; /* end */ - GLfloat dx, dy; /* direction vector */ - GLfloat len; /* length */ - GLfloat halfWidth; /* half of line width */ - GLfloat xAdj, yAdj; /* X and Y adjustment for quad corners around line */ - /* for coverage computation */ - GLfloat qx0, qy0; /* quad vertices */ - GLfloat qx1, qy1; - GLfloat qx2, qy2; - GLfloat qx3, qy3; - GLfloat ex0, ey0; /* quad edge vectors */ - GLfloat ex1, ey1; - GLfloat ex2, ey2; - GLfloat ex3, ey3; - - /* DO_Z */ - GLfloat zPlane[4]; - /* DO_RGBA - always enabled */ - GLfloat rPlane[4], gPlane[4], bPlane[4], aPlane[4]; - /* DO_ATTRIBS */ - GLfloat wPlane[4]; - GLfloat attrPlane[FRAG_ATTRIB_MAX][4][4]; - GLfloat lambda[FRAG_ATTRIB_MAX]; - GLfloat texWidth[FRAG_ATTRIB_MAX]; - GLfloat texHeight[FRAG_ATTRIB_MAX]; - - SWspan span; -}; - - - -/* - * Compute the equation of a plane used to interpolate line fragment data - * such as color, Z, texture coords, etc. - * Input: (x0, y0) and (x1,y1) are the endpoints of the line. - * z0, and z1 are the end point values to interpolate. - * Output: plane - the plane equation. - * - * Note: we don't really have enough parameters to specify a plane. - * We take the endpoints of the line and compute a plane such that - * the cross product of the line vector and the plane normal is - * parallel to the projection plane. - */ -static void -compute_plane(GLfloat x0, GLfloat y0, GLfloat x1, GLfloat y1, - GLfloat z0, GLfloat z1, GLfloat plane[4]) -{ -#if 0 - /* original */ - const GLfloat px = x1 - x0; - const GLfloat py = y1 - y0; - const GLfloat pz = z1 - z0; - const GLfloat qx = -py; - const GLfloat qy = px; - const GLfloat qz = 0; - const GLfloat a = py * qz - pz * qy; - const GLfloat b = pz * qx - px * qz; - const GLfloat c = px * qy - py * qx; - const GLfloat d = -(a * x0 + b * y0 + c * z0); - plane[0] = a; - plane[1] = b; - plane[2] = c; - plane[3] = d; -#else - /* simplified */ - const GLfloat px = x1 - x0; - const GLfloat py = y1 - y0; - const GLfloat pz = z0 - z1; - const GLfloat a = pz * px; - const GLfloat b = pz * py; - const GLfloat c = px * px + py * py; - const GLfloat d = -(a * x0 + b * y0 + c * z0); - if (a == 0.0 && b == 0.0 && c == 0.0 && d == 0.0) { - plane[0] = 0.0; - plane[1] = 0.0; - plane[2] = 1.0; - plane[3] = 0.0; - } - else { - plane[0] = a; - plane[1] = b; - plane[2] = c; - plane[3] = d; - } -#endif -} - - -static INLINE void -constant_plane(GLfloat value, GLfloat plane[4]) -{ - plane[0] = 0.0; - plane[1] = 0.0; - plane[2] = -1.0; - plane[3] = value; -} - - -static INLINE GLfloat -solve_plane(GLfloat x, GLfloat y, const GLfloat plane[4]) -{ - const GLfloat z = (plane[3] + plane[0] * x + plane[1] * y) / -plane[2]; - return z; -} - -#define SOLVE_PLANE(X, Y, PLANE) \ - ((PLANE[3] + PLANE[0] * (X) + PLANE[1] * (Y)) / -PLANE[2]) - - -/* - * Return 1 / solve_plane(). - */ -static INLINE GLfloat -solve_plane_recip(GLfloat x, GLfloat y, const GLfloat plane[4]) -{ - const GLfloat denom = plane[3] + plane[0] * x + plane[1] * y; - if (denom == 0.0) - return 0.0; - else - return -plane[2] / denom; -} - - -/* - * Solve plane and return clamped GLchan value. - */ -static INLINE GLchan -solve_plane_chan(GLfloat x, GLfloat y, const GLfloat plane[4]) -{ - const GLfloat z = (plane[3] + plane[0] * x + plane[1] * y) / -plane[2]; -#if CHAN_TYPE == GL_FLOAT - return CLAMP(z, 0.0F, CHAN_MAXF); -#else - if (z < 0) - return 0; - else if (z > CHAN_MAX) - return CHAN_MAX; - return (GLchan) IROUND_POS(z); -#endif -} - - -/* - * Compute mipmap level of detail. - */ -static INLINE GLfloat -compute_lambda(const GLfloat sPlane[4], const GLfloat tPlane[4], - GLfloat invQ, GLfloat width, GLfloat height) -{ - GLfloat dudx = sPlane[0] / sPlane[2] * invQ * width; - GLfloat dudy = sPlane[1] / sPlane[2] * invQ * width; - GLfloat dvdx = tPlane[0] / tPlane[2] * invQ * height; - GLfloat dvdy = tPlane[1] / tPlane[2] * invQ * height; - GLfloat r1 = dudx * dudx + dudy * dudy; - GLfloat r2 = dvdx * dvdx + dvdy * dvdy; - GLfloat rho2 = r1 + r2; - /* return log base 2 of rho */ - if (rho2 == 0.0F) - return 0.0; - else - return (GLfloat) (LOGF(rho2) * 1.442695 * 0.5);/* 1.442695 = 1/log(2) */ -} - - - - -/* - * Fill in the samples[] array with the (x,y) subpixel positions of - * xSamples * ySamples sample positions. - * Note that the four corner samples are put into the first four - * positions of the array. This allows us to optimize for the common - * case of all samples being inside the polygon. - */ -static void -make_sample_table(GLint xSamples, GLint ySamples, GLfloat samples[][2]) -{ - const GLfloat dx = 1.0F / (GLfloat) xSamples; - const GLfloat dy = 1.0F / (GLfloat) ySamples; - GLint x, y; - GLint i; - - i = 4; - for (x = 0; x < xSamples; x++) { - for (y = 0; y < ySamples; y++) { - GLint j; - if (x == 0 && y == 0) { - /* lower left */ - j = 0; - } - else if (x == xSamples - 1 && y == 0) { - /* lower right */ - j = 1; - } - else if (x == 0 && y == ySamples - 1) { - /* upper left */ - j = 2; - } - else if (x == xSamples - 1 && y == ySamples - 1) { - /* upper right */ - j = 3; - } - else { - j = i++; - } - samples[j][0] = x * dx + 0.5F * dx; - samples[j][1] = y * dy + 0.5F * dy; - } - } -} - - - -/* - * Compute how much of the given pixel's area is inside the rectangle - * defined by vertices v0, v1, v2, v3. - * Vertices MUST be specified in counter-clockwise order. - * Return: coverage in [0, 1]. - */ -static GLfloat -compute_coveragef(const struct LineInfo *info, - GLint winx, GLint winy) -{ - static GLfloat samples[SUB_PIXEL * SUB_PIXEL][2]; - static GLboolean haveSamples = GL_FALSE; - const GLfloat x = (GLfloat) winx; - const GLfloat y = (GLfloat) winy; - GLint stop = 4, i; - GLfloat insideCount = SUB_PIXEL * SUB_PIXEL; - - if (!haveSamples) { - make_sample_table(SUB_PIXEL, SUB_PIXEL, samples); - haveSamples = GL_TRUE; - } - -#if 0 /*DEBUG*/ - { - const GLfloat area = dx0 * dy1 - dx1 * dy0; - assert(area >= 0.0); - } -#endif - - for (i = 0; i < stop; i++) { - const GLfloat sx = x + samples[i][0]; - const GLfloat sy = y + samples[i][1]; - const GLfloat fx0 = sx - info->qx0; - const GLfloat fy0 = sy - info->qy0; - const GLfloat fx1 = sx - info->qx1; - const GLfloat fy1 = sy - info->qy1; - const GLfloat fx2 = sx - info->qx2; - const GLfloat fy2 = sy - info->qy2; - const GLfloat fx3 = sx - info->qx3; - const GLfloat fy3 = sy - info->qy3; - /* cross product determines if sample is inside or outside each edge */ - GLfloat cross0 = (info->ex0 * fy0 - info->ey0 * fx0); - GLfloat cross1 = (info->ex1 * fy1 - info->ey1 * fx1); - GLfloat cross2 = (info->ex2 * fy2 - info->ey2 * fx2); - GLfloat cross3 = (info->ex3 * fy3 - info->ey3 * fx3); - /* Check if the sample is exactly on an edge. If so, let cross be a - * positive or negative value depending on the direction of the edge. - */ - if (cross0 == 0.0F) - cross0 = info->ex0 + info->ey0; - if (cross1 == 0.0F) - cross1 = info->ex1 + info->ey1; - if (cross2 == 0.0F) - cross2 = info->ex2 + info->ey2; - if (cross3 == 0.0F) - cross3 = info->ex3 + info->ey3; - if (cross0 < 0.0F || cross1 < 0.0F || cross2 < 0.0F || cross3 < 0.0F) { - /* point is outside quadrilateral */ - insideCount -= 1.0F; - stop = SUB_PIXEL * SUB_PIXEL; - } - } - if (stop == 4) - return 1.0F; - else - return insideCount * (1.0F / (SUB_PIXEL * SUB_PIXEL)); -} - - -typedef void (*plot_func)(GLcontext *ctx, struct LineInfo *line, - int ix, int iy); - - - -/* - * Draw an AA line segment (called many times per line when stippling) - */ -static void -segment(GLcontext *ctx, - struct LineInfo *line, - plot_func plot, - GLfloat t0, GLfloat t1) -{ - const GLfloat absDx = (line->dx < 0.0F) ? -line->dx : line->dx; - const GLfloat absDy = (line->dy < 0.0F) ? -line->dy : line->dy; - /* compute the actual segment's endpoints */ - const GLfloat x0 = line->x0 + t0 * line->dx; - const GLfloat y0 = line->y0 + t0 * line->dy; - const GLfloat x1 = line->x0 + t1 * line->dx; - const GLfloat y1 = line->y0 + t1 * line->dy; - - /* compute vertices of the line-aligned quadrilateral */ - line->qx0 = x0 - line->yAdj; - line->qy0 = y0 + line->xAdj; - line->qx1 = x0 + line->yAdj; - line->qy1 = y0 - line->xAdj; - line->qx2 = x1 + line->yAdj; - line->qy2 = y1 - line->xAdj; - line->qx3 = x1 - line->yAdj; - line->qy3 = y1 + line->xAdj; - /* compute the quad's edge vectors (for coverage calc) */ - line->ex0 = line->qx1 - line->qx0; - line->ey0 = line->qy1 - line->qy0; - line->ex1 = line->qx2 - line->qx1; - line->ey1 = line->qy2 - line->qy1; - line->ex2 = line->qx3 - line->qx2; - line->ey2 = line->qy3 - line->qy2; - line->ex3 = line->qx0 - line->qx3; - line->ey3 = line->qy0 - line->qy3; - - if (absDx > absDy) { - /* X-major line */ - GLfloat dydx = line->dy / line->dx; - GLfloat xLeft, xRight, yBot, yTop; - GLint ix, ixRight; - if (x0 < x1) { - xLeft = x0 - line->halfWidth; - xRight = x1 + line->halfWidth; - if (line->dy >= 0.0) { - yBot = y0 - 3.0F * line->halfWidth; - yTop = y0 + line->halfWidth; - } - else { - yBot = y0 - line->halfWidth; - yTop = y0 + 3.0F * line->halfWidth; - } - } - else { - xLeft = x1 - line->halfWidth; - xRight = x0 + line->halfWidth; - if (line->dy <= 0.0) { - yBot = y1 - 3.0F * line->halfWidth; - yTop = y1 + line->halfWidth; - } - else { - yBot = y1 - line->halfWidth; - yTop = y1 + 3.0F * line->halfWidth; - } - } - - /* scan along the line, left-to-right */ - ixRight = (GLint) (xRight + 1.0F); - - /*printf("avg span height: %g\n", yTop - yBot);*/ - for (ix = (GLint) xLeft; ix < ixRight; ix++) { - const GLint iyBot = (GLint) yBot; - const GLint iyTop = (GLint) (yTop + 1.0F); - GLint iy; - /* scan across the line, bottom-to-top */ - for (iy = iyBot; iy < iyTop; iy++) { - (*plot)(ctx, line, ix, iy); - } - yBot += dydx; - yTop += dydx; - } - } - else { - /* Y-major line */ - GLfloat dxdy = line->dx / line->dy; - GLfloat yBot, yTop, xLeft, xRight; - GLint iy, iyTop; - if (y0 < y1) { - yBot = y0 - line->halfWidth; - yTop = y1 + line->halfWidth; - if (line->dx >= 0.0) { - xLeft = x0 - 3.0F * line->halfWidth; - xRight = x0 + line->halfWidth; - } - else { - xLeft = x0 - line->halfWidth; - xRight = x0 + 3.0F * line->halfWidth; - } - } - else { - yBot = y1 - line->halfWidth; - yTop = y0 + line->halfWidth; - if (line->dx <= 0.0) { - xLeft = x1 - 3.0F * line->halfWidth; - xRight = x1 + line->halfWidth; - } - else { - xLeft = x1 - line->halfWidth; - xRight = x1 + 3.0F * line->halfWidth; - } - } - - /* scan along the line, bottom-to-top */ - iyTop = (GLint) (yTop + 1.0F); - - /*printf("avg span width: %g\n", xRight - xLeft);*/ - for (iy = (GLint) yBot; iy < iyTop; iy++) { - const GLint ixLeft = (GLint) xLeft; - const GLint ixRight = (GLint) (xRight + 1.0F); - GLint ix; - /* scan across the line, left-to-right */ - for (ix = ixLeft; ix < ixRight; ix++) { - (*plot)(ctx, line, ix, iy); - } - xLeft += dxdy; - xRight += dxdy; - } - } -} - - -#define NAME(x) aa_rgba_##x -#define DO_Z -#include "s_aalinetemp.h" - - -#define NAME(x) aa_general_rgba_##x -#define DO_Z -#define DO_ATTRIBS -#include "s_aalinetemp.h" - - - -void -_swrast_choose_aa_line_function(GLcontext *ctx) -{ - SWcontext *swrast = SWRAST_CONTEXT(ctx); - - ASSERT(ctx->Line.SmoothFlag); - - if (ctx->Texture._EnabledCoordUnits != 0 - || ctx->FragmentProgram._Current - || (ctx->Light.Enabled && - ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR) - || ctx->Fog.ColorSumEnabled - || swrast->_FogEnabled) { - swrast->Line = aa_general_rgba_line; - } - else { - swrast->Line = aa_rgba_line; - } -} +/*
+ * Mesa 3-D graphics library
+ * Version: 6.5.3
+ *
+ * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * 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
+ * BRIAN PAUL 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.
+ */
+
+
+#include "main/glheader.h"
+#include "main/imports.h"
+#include "main/macros.h"
+#include "main/mtypes.h"
+#include "swrast/s_aaline.h"
+#include "swrast/s_context.h"
+#include "swrast/s_span.h"
+#include "swrast/swrast.h"
+
+
+#define SUB_PIXEL 4
+
+
+/*
+ * Info about the AA line we're rendering
+ */
+struct LineInfo
+{
+ GLfloat x0, y0; /* start */
+ GLfloat x1, y1; /* end */
+ GLfloat dx, dy; /* direction vector */
+ GLfloat len; /* length */
+ GLfloat halfWidth; /* half of line width */
+ GLfloat xAdj, yAdj; /* X and Y adjustment for quad corners around line */
+ /* for coverage computation */
+ GLfloat qx0, qy0; /* quad vertices */
+ GLfloat qx1, qy1;
+ GLfloat qx2, qy2;
+ GLfloat qx3, qy3;
+ GLfloat ex0, ey0; /* quad edge vectors */
+ GLfloat ex1, ey1;
+ GLfloat ex2, ey2;
+ GLfloat ex3, ey3;
+
+ /* DO_Z */
+ GLfloat zPlane[4];
+ /* DO_RGBA - always enabled */
+ GLfloat rPlane[4], gPlane[4], bPlane[4], aPlane[4];
+ /* DO_ATTRIBS */
+ GLfloat wPlane[4];
+ GLfloat attrPlane[FRAG_ATTRIB_MAX][4][4];
+ GLfloat lambda[FRAG_ATTRIB_MAX];
+ GLfloat texWidth[FRAG_ATTRIB_MAX];
+ GLfloat texHeight[FRAG_ATTRIB_MAX];
+
+ SWspan span;
+};
+
+
+
+/*
+ * Compute the equation of a plane used to interpolate line fragment data
+ * such as color, Z, texture coords, etc.
+ * Input: (x0, y0) and (x1,y1) are the endpoints of the line.
+ * z0, and z1 are the end point values to interpolate.
+ * Output: plane - the plane equation.
+ *
+ * Note: we don't really have enough parameters to specify a plane.
+ * We take the endpoints of the line and compute a plane such that
+ * the cross product of the line vector and the plane normal is
+ * parallel to the projection plane.
+ */
+static void
+compute_plane(GLfloat x0, GLfloat y0, GLfloat x1, GLfloat y1,
+ GLfloat z0, GLfloat z1, GLfloat plane[4])
+{
+#if 0
+ /* original */
+ const GLfloat px = x1 - x0;
+ const GLfloat py = y1 - y0;
+ const GLfloat pz = z1 - z0;
+ const GLfloat qx = -py;
+ const GLfloat qy = px;
+ const GLfloat qz = 0;
+ const GLfloat a = py * qz - pz * qy;
+ const GLfloat b = pz * qx - px * qz;
+ const GLfloat c = px * qy - py * qx;
+ const GLfloat d = -(a * x0 + b * y0 + c * z0);
+ plane[0] = a;
+ plane[1] = b;
+ plane[2] = c;
+ plane[3] = d;
+#else
+ /* simplified */
+ const GLfloat px = x1 - x0;
+ const GLfloat py = y1 - y0;
+ const GLfloat pz = z0 - z1;
+ const GLfloat a = pz * px;
+ const GLfloat b = pz * py;
+ const GLfloat c = px * px + py * py;
+ const GLfloat d = -(a * x0 + b * y0 + c * z0);
+ if (a == 0.0 && b == 0.0 && c == 0.0 && d == 0.0) {
+ plane[0] = 0.0;
+ plane[1] = 0.0;
+ plane[2] = 1.0;
+ plane[3] = 0.0;
+ }
+ else {
+ plane[0] = a;
+ plane[1] = b;
+ plane[2] = c;
+ plane[3] = d;
+ }
+#endif
+}
+
+
+static INLINE void
+constant_plane(GLfloat value, GLfloat plane[4])
+{
+ plane[0] = 0.0;
+ plane[1] = 0.0;
+ plane[2] = -1.0;
+ plane[3] = value;
+}
+
+
+static INLINE GLfloat
+solve_plane(GLfloat x, GLfloat y, const GLfloat plane[4])
+{
+ const GLfloat z = (plane[3] + plane[0] * x + plane[1] * y) / -plane[2];
+ return z;
+}
+
+#define SOLVE_PLANE(X, Y, PLANE) \
+ ((PLANE[3] + PLANE[0] * (X) + PLANE[1] * (Y)) / -PLANE[2])
+
+
+/*
+ * Return 1 / solve_plane().
+ */
+static INLINE GLfloat
+solve_plane_recip(GLfloat x, GLfloat y, const GLfloat plane[4])
+{
+ const GLfloat denom = plane[3] + plane[0] * x + plane[1] * y;
+ if (denom == 0.0)
+ return 0.0;
+ else
+ return -plane[2] / denom;
+}
+
+
+/*
+ * Solve plane and return clamped GLchan value.
+ */
+static INLINE GLchan
+solve_plane_chan(GLfloat x, GLfloat y, const GLfloat plane[4])
+{
+ const GLfloat z = (plane[3] + plane[0] * x + plane[1] * y) / -plane[2];
+#if CHAN_TYPE == GL_FLOAT
+ return CLAMP(z, 0.0F, CHAN_MAXF);
+#else
+ if (z < 0)
+ return 0;
+ else if (z > CHAN_MAX)
+ return CHAN_MAX;
+ return (GLchan) IROUND_POS(z);
+#endif
+}
+
+
+/*
+ * Compute mipmap level of detail.
+ */
+static INLINE GLfloat
+compute_lambda(const GLfloat sPlane[4], const GLfloat tPlane[4],
+ GLfloat invQ, GLfloat width, GLfloat height)
+{
+ GLfloat dudx = sPlane[0] / sPlane[2] * invQ * width;
+ GLfloat dudy = sPlane[1] / sPlane[2] * invQ * width;
+ GLfloat dvdx = tPlane[0] / tPlane[2] * invQ * height;
+ GLfloat dvdy = tPlane[1] / tPlane[2] * invQ * height;
+ GLfloat r1 = dudx * dudx + dudy * dudy;
+ GLfloat r2 = dvdx * dvdx + dvdy * dvdy;
+ GLfloat rho2 = r1 + r2;
+ /* return log base 2 of rho */
+ if (rho2 == 0.0F)
+ return 0.0;
+ else
+ return (GLfloat) (LOGF(rho2) * 1.442695 * 0.5);/* 1.442695 = 1/log(2) */
+}
+
+
+
+
+/*
+ * Fill in the samples[] array with the (x,y) subpixel positions of
+ * xSamples * ySamples sample positions.
+ * Note that the four corner samples are put into the first four
+ * positions of the array. This allows us to optimize for the common
+ * case of all samples being inside the polygon.
+ */
+static void
+make_sample_table(GLint xSamples, GLint ySamples, GLfloat samples[][2])
+{
+ const GLfloat dx = 1.0F / (GLfloat) xSamples;
+ const GLfloat dy = 1.0F / (GLfloat) ySamples;
+ GLint x, y;
+ GLint i;
+
+ i = 4;
+ for (x = 0; x < xSamples; x++) {
+ for (y = 0; y < ySamples; y++) {
+ GLint j;
+ if (x == 0 && y == 0) {
+ /* lower left */
+ j = 0;
+ }
+ else if (x == xSamples - 1 && y == 0) {
+ /* lower right */
+ j = 1;
+ }
+ else if (x == 0 && y == ySamples - 1) {
+ /* upper left */
+ j = 2;
+ }
+ else if (x == xSamples - 1 && y == ySamples - 1) {
+ /* upper right */
+ j = 3;
+ }
+ else {
+ j = i++;
+ }
+ samples[j][0] = x * dx + 0.5F * dx;
+ samples[j][1] = y * dy + 0.5F * dy;
+ }
+ }
+}
+
+
+
+/*
+ * Compute how much of the given pixel's area is inside the rectangle
+ * defined by vertices v0, v1, v2, v3.
+ * Vertices MUST be specified in counter-clockwise order.
+ * Return: coverage in [0, 1].
+ */
+static GLfloat
+compute_coveragef(const struct LineInfo *info,
+ GLint winx, GLint winy)
+{
+ static GLfloat samples[SUB_PIXEL * SUB_PIXEL][2];
+ static GLboolean haveSamples = GL_FALSE;
+ const GLfloat x = (GLfloat) winx;
+ const GLfloat y = (GLfloat) winy;
+ GLint stop = 4, i;
+ GLfloat insideCount = SUB_PIXEL * SUB_PIXEL;
+
+ if (!haveSamples) {
+ make_sample_table(SUB_PIXEL, SUB_PIXEL, samples);
+ haveSamples = GL_TRUE;
+ }
+
+#if 0 /*DEBUG*/
+ {
+ const GLfloat area = dx0 * dy1 - dx1 * dy0;
+ assert(area >= 0.0);
+ }
+#endif
+
+ for (i = 0; i < stop; i++) {
+ const GLfloat sx = x + samples[i][0];
+ const GLfloat sy = y + samples[i][1];
+ const GLfloat fx0 = sx - info->qx0;
+ const GLfloat fy0 = sy - info->qy0;
+ const GLfloat fx1 = sx - info->qx1;
+ const GLfloat fy1 = sy - info->qy1;
+ const GLfloat fx2 = sx - info->qx2;
+ const GLfloat fy2 = sy - info->qy2;
+ const GLfloat fx3 = sx - info->qx3;
+ const GLfloat fy3 = sy - info->qy3;
+ /* cross product determines if sample is inside or outside each edge */
+ GLfloat cross0 = (info->ex0 * fy0 - info->ey0 * fx0);
+ GLfloat cross1 = (info->ex1 * fy1 - info->ey1 * fx1);
+ GLfloat cross2 = (info->ex2 * fy2 - info->ey2 * fx2);
+ GLfloat cross3 = (info->ex3 * fy3 - info->ey3 * fx3);
+ /* Check if the sample is exactly on an edge. If so, let cross be a
+ * positive or negative value depending on the direction of the edge.
+ */
+ if (cross0 == 0.0F)
+ cross0 = info->ex0 + info->ey0;
+ if (cross1 == 0.0F)
+ cross1 = info->ex1 + info->ey1;
+ if (cross2 == 0.0F)
+ cross2 = info->ex2 + info->ey2;
+ if (cross3 == 0.0F)
+ cross3 = info->ex3 + info->ey3;
+ if (cross0 < 0.0F || cross1 < 0.0F || cross2 < 0.0F || cross3 < 0.0F) {
+ /* point is outside quadrilateral */
+ insideCount -= 1.0F;
+ stop = SUB_PIXEL * SUB_PIXEL;
+ }
+ }
+ if (stop == 4)
+ return 1.0F;
+ else
+ return insideCount * (1.0F / (SUB_PIXEL * SUB_PIXEL));
+}
+
+
+typedef void (*plot_func)(struct gl_context *ctx, struct LineInfo *line,
+ int ix, int iy);
+
+
+
+/*
+ * Draw an AA line segment (called many times per line when stippling)
+ */
+static void
+segment(struct gl_context *ctx,
+ struct LineInfo *line,
+ plot_func plot,
+ GLfloat t0, GLfloat t1)
+{
+ const GLfloat absDx = (line->dx < 0.0F) ? -line->dx : line->dx;
+ const GLfloat absDy = (line->dy < 0.0F) ? -line->dy : line->dy;
+ /* compute the actual segment's endpoints */
+ const GLfloat x0 = line->x0 + t0 * line->dx;
+ const GLfloat y0 = line->y0 + t0 * line->dy;
+ const GLfloat x1 = line->x0 + t1 * line->dx;
+ const GLfloat y1 = line->y0 + t1 * line->dy;
+
+ /* compute vertices of the line-aligned quadrilateral */
+ line->qx0 = x0 - line->yAdj;
+ line->qy0 = y0 + line->xAdj;
+ line->qx1 = x0 + line->yAdj;
+ line->qy1 = y0 - line->xAdj;
+ line->qx2 = x1 + line->yAdj;
+ line->qy2 = y1 - line->xAdj;
+ line->qx3 = x1 - line->yAdj;
+ line->qy3 = y1 + line->xAdj;
+ /* compute the quad's edge vectors (for coverage calc) */
+ line->ex0 = line->qx1 - line->qx0;
+ line->ey0 = line->qy1 - line->qy0;
+ line->ex1 = line->qx2 - line->qx1;
+ line->ey1 = line->qy2 - line->qy1;
+ line->ex2 = line->qx3 - line->qx2;
+ line->ey2 = line->qy3 - line->qy2;
+ line->ex3 = line->qx0 - line->qx3;
+ line->ey3 = line->qy0 - line->qy3;
+
+ if (absDx > absDy) {
+ /* X-major line */
+ GLfloat dydx = line->dy / line->dx;
+ GLfloat xLeft, xRight, yBot, yTop;
+ GLint ix, ixRight;
+ if (x0 < x1) {
+ xLeft = x0 - line->halfWidth;
+ xRight = x1 + line->halfWidth;
+ if (line->dy >= 0.0) {
+ yBot = y0 - 3.0F * line->halfWidth;
+ yTop = y0 + line->halfWidth;
+ }
+ else {
+ yBot = y0 - line->halfWidth;
+ yTop = y0 + 3.0F * line->halfWidth;
+ }
+ }
+ else {
+ xLeft = x1 - line->halfWidth;
+ xRight = x0 + line->halfWidth;
+ if (line->dy <= 0.0) {
+ yBot = y1 - 3.0F * line->halfWidth;
+ yTop = y1 + line->halfWidth;
+ }
+ else {
+ yBot = y1 - line->halfWidth;
+ yTop = y1 + 3.0F * line->halfWidth;
+ }
+ }
+
+ /* scan along the line, left-to-right */
+ ixRight = (GLint) (xRight + 1.0F);
+
+ /*printf("avg span height: %g\n", yTop - yBot);*/
+ for (ix = (GLint) xLeft; ix < ixRight; ix++) {
+ const GLint iyBot = (GLint) yBot;
+ const GLint iyTop = (GLint) (yTop + 1.0F);
+ GLint iy;
+ /* scan across the line, bottom-to-top */
+ for (iy = iyBot; iy < iyTop; iy++) {
+ (*plot)(ctx, line, ix, iy);
+ }
+ yBot += dydx;
+ yTop += dydx;
+ }
+ }
+ else {
+ /* Y-major line */
+ GLfloat dxdy = line->dx / line->dy;
+ GLfloat yBot, yTop, xLeft, xRight;
+ GLint iy, iyTop;
+ if (y0 < y1) {
+ yBot = y0 - line->halfWidth;
+ yTop = y1 + line->halfWidth;
+ if (line->dx >= 0.0) {
+ xLeft = x0 - 3.0F * line->halfWidth;
+ xRight = x0 + line->halfWidth;
+ }
+ else {
+ xLeft = x0 - line->halfWidth;
+ xRight = x0 + 3.0F * line->halfWidth;
+ }
+ }
+ else {
+ yBot = y1 - line->halfWidth;
+ yTop = y0 + line->halfWidth;
+ if (line->dx <= 0.0) {
+ xLeft = x1 - 3.0F * line->halfWidth;
+ xRight = x1 + line->halfWidth;
+ }
+ else {
+ xLeft = x1 - line->halfWidth;
+ xRight = x1 + 3.0F * line->halfWidth;
+ }
+ }
+
+ /* scan along the line, bottom-to-top */
+ iyTop = (GLint) (yTop + 1.0F);
+
+ /*printf("avg span width: %g\n", xRight - xLeft);*/
+ for (iy = (GLint) yBot; iy < iyTop; iy++) {
+ const GLint ixLeft = (GLint) xLeft;
+ const GLint ixRight = (GLint) (xRight + 1.0F);
+ GLint ix;
+ /* scan across the line, left-to-right */
+ for (ix = ixLeft; ix < ixRight; ix++) {
+ (*plot)(ctx, line, ix, iy);
+ }
+ xLeft += dxdy;
+ xRight += dxdy;
+ }
+ }
+}
+
+
+#define NAME(x) aa_rgba_##x
+#define DO_Z
+#include "s_aalinetemp.h"
+
+
+#define NAME(x) aa_general_rgba_##x
+#define DO_Z
+#define DO_ATTRIBS
+#include "s_aalinetemp.h"
+
+
+
+void
+_swrast_choose_aa_line_function(struct gl_context *ctx)
+{
+ SWcontext *swrast = SWRAST_CONTEXT(ctx);
+
+ ASSERT(ctx->Line.SmoothFlag);
+
+ if (ctx->Texture._EnabledCoordUnits != 0
+ || ctx->FragmentProgram._Current
+ || (ctx->Light.Enabled &&
+ ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)
+ || ctx->Fog.ColorSumEnabled
+ || swrast->_FogEnabled) {
+ swrast->Line = aa_general_rgba_line;
+ }
+ else {
+ swrast->Line = aa_rgba_line;
+ }
+}
|