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-rw-r--r--mesalib/src/mesa/swrast/s_aaline.c984
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 be817f326..d4b1805d9 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)(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;
- }
-}
+/*
+ * 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;
+ }
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-10 17:46:33 +0000