GL conformance tests for AA lines (but not tried yet).
TODO: improve code sharing with the AA triangle code.
--- /dev/null
+/* $Id: s_aaline.c,v 1.1 2000/11/05 23:15:16 brianp Exp $ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version: 3.5
+ *
+ * Copyright (C) 1999-2000 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 "glheader.h"
+#include "swrast/s_aaline.h"
+#include "swrast/s_pb.h"
+#include "swrast/s_context.h"
+#include "swrast/swrast.h"
+#include "types.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_FOG */
+ GLfloat fPlane[4];
+ /* DO_RGBA */
+ GLfloat rPlane[4], gPlane[4], bPlane[4], aPlane[4];
+ /* DO_INDEX */
+ GLfloat iPlane[4];
+ /* DO_SPEC */
+ GLfloat srPlane[4], sgPlane[4], sbPlane[4];
+ /* DO_TEX or DO_MULTITEX */
+ GLfloat sPlane[MAX_TEXTURE_UNITS][4];
+ GLfloat tPlane[MAX_TEXTURE_UNITS][4];
+ GLfloat uPlane[MAX_TEXTURE_UNITS][4];
+ GLfloat vPlane[MAX_TEXTURE_UNITS][4];
+ GLfloat lambda[MAX_TEXTURE_UNITS];
+ GLfloat texWidth[MAX_TEXTURE_UNITS], texHeight[MAX_TEXTURE_UNITS];
+};
+
+
+
+/*
+ * 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);
+ 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])
+{
+ 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])
+{
+ GLfloat z = -plane[2] / (plane[3] + plane[0] * x + plane[1] * y);
+ return z;
+}
+
+
+/*
+ * Solve plane and return clamped GLchan value.
+ */
+static INLINE GLchan
+solve_plane_chan(GLfloat x, GLfloat y, const GLfloat plane[4])
+{
+ GLfloat z = (plane[3] + plane[0] * x + plane[1] * y) / -plane[2] + 0.5F;
+ if (z < 0.0F)
+ return 0;
+ else if (z > CHAN_MAXF)
+ return CHAN_MAXF;
+ return (GLchan) (GLint) z;
+}
+
+
+/*
+ * 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 */
+ return log(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;
+ samples[j][1] = y * 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, const struct LineInfo *line,
+ struct pixel_buffer *pb, 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,
+ struct pixel_buffer *pb,
+ 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 - 3.0 * line->halfWidth;
+ yTop = y0 + line->halfWidth;
+ }
+ else {
+ yBot = y0 - line->halfWidth;
+ yTop = y0 + 3.0 * line->halfWidth;
+ }
+ }
+ else {
+ xLeft = x1 - line->halfWidth;
+ xRight = x0 + line->halfWidth;
+ if (line->dy <= 0.0) {
+ yBot = y1 - 3.0 * line->halfWidth;
+ yTop = y1 + line->halfWidth;
+ }
+ else {
+ yBot = y1 - line->halfWidth;
+ yTop = y1 + 3.0 * 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, pb, 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 - 3.0 * line->halfWidth;
+ xRight = x0 + line->halfWidth;
+ }
+ else {
+ xLeft = x0 - line->halfWidth;
+ xRight = x0 + 3.0 * line->halfWidth;
+ }
+ }
+ else {
+ yBot = y1 - line->halfWidth;
+ yTop = y0 + line->halfWidth;
+ if (line->dx <= 0.0) {
+ xLeft = x1 - 3.0 * line->halfWidth;
+ xRight = x1 + line->halfWidth;
+ }
+ else {
+ xLeft = x1 - line->halfWidth;
+ xRight = x1 + 3.0 * 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, pb, ix, iy);
+ }
+ xLeft += dxdy;
+ xRight += dxdy;
+ }
+ }
+}
+
+
+#define NAME(x) aa_ci_##x
+#define DO_Z
+#define DO_FOG
+#define DO_INDEX
+#include "s_aalinetemp.h"
+
+
+#define NAME(x) aa_rgba_##x
+#define DO_Z
+#define DO_FOG
+#define DO_RGBA
+#include "s_aalinetemp.h"
+
+
+#define NAME(x) aa_tex_rgba_##x
+#define DO_Z
+#define DO_FOG
+#define DO_RGBA
+#define DO_TEX
+#include "s_aalinetemp.h"
+
+
+#define NAME(x) aa_multitex_rgba_##x
+#define DO_Z
+#define DO_RGBA
+#define DO_MULTITEX
+#define DO_SPEC
+#include "s_aalinetemp.h"
+
+
+
+void
+_swrast_choose_aa_line_function(GLcontext *ctx)
+{
+ SWcontext *swrast = SWRAST_CONTEXT(ctx);
+
+ ASSERT(ctx->Line.SmoothFlag);
+
+ if (ctx->Visual.RGBAflag) {
+ /* RGBA */
+ if (ctx->Texture._ReallyEnabled) {
+ if (ctx->Texture._MultiTextureEnabled
+ || ctx->Light.Model.ColorControl==GL_SEPARATE_SPECULAR_COLOR
+ || ctx->Fog.ColorSumEnabled)
+ /* Multitextured! */
+ swrast->Line = aa_multitex_rgba_line;
+ else
+ swrast->Line = aa_tex_rgba_line;
+ }
+ else {
+ swrast->Line = aa_rgba_line;
+ }
+ }
+ else {
+ /* Color Index */
+ swrast->Line = aa_ci_line;
+ }
+}
+
--- /dev/null
+/* $Id: s_aaline.h,v 1.1 2000/11/05 23:15:16 brianp Exp $ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version: 3.5
+ *
+ * Copyright (C) 1999-2000 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.
+ */
+
+
+#ifndef S_AALINE_H
+#define S_AALINE_H
+
+
+#include "types.h"
+#include "swrast.h"
+
+
+extern void
+_swrast_choose_aa_line_function(GLcontext *ctx);
+
+
+#endif
--- /dev/null
+/* $Id: s_aalinetemp.h,v 1.1 2000/11/05 23:15:16 brianp Exp $ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version: 3.5
+ *
+ * Copyright (C) 1999-2000 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.
+ */
+
+
+/*
+ * Antialiased line template.
+ */
+
+
+/*
+ * Function to render each fragment in the AA line.
+ */
+static void
+NAME(plot)(GLcontext *ctx, const struct LineInfo *line,
+ struct pixel_buffer *pb, int ix, int iy)
+{
+ const GLfloat fx = (GLfloat) ix;
+ const GLfloat fy = (GLfloat) iy;
+ const GLfloat coverage = compute_coveragef(line, ix, iy);
+ GLdepth z;
+ GLfloat fog;
+ GLchan red, green, blue, alpha;
+ GLint frac, indx, index;
+ GLchan specRed, specGreen, specBlue;
+ GLfloat tex[MAX_TEXTURE_UNITS][4], lambda[MAX_TEXTURE_UNITS];
+
+ if (coverage == 0.0)
+ return;
+
+ /*
+ * Compute Z, color, texture coords, fog for the fragment by
+ * solving the plane equations at (ix,iy).
+ */
+#ifdef DO_Z
+ z = (GLdepth) solve_plane(fx, fy, line->zPlane);
+#else
+ z = 0.0;
+#endif
+#ifdef DO_FOG
+ fog = solve_plane(fx, fy, line->fPlane);
+#else
+ fog = 0.0;
+#endif
+#ifdef DO_RGBA
+ red = solve_plane_chan(fx, fy, line->rPlane);
+ green = solve_plane_chan(fx, fy, line->gPlane);
+ blue = solve_plane_chan(fx, fy, line->bPlane);
+ alpha = (GLchan) (solve_plane_chan(fx, fy, line->aPlane) * coverage);;
+#else
+ (void) red;
+ (void) green;
+ (void) blue;
+ (void) alpha;
+#endif
+#ifdef DO_INDEX
+ frac = (GLint) (15.0 * coverage);
+ indx = (GLint) solve_plane(fx, fy, line->iPlane);
+ index = (indx & ~0xf) | frac;
+#else
+ (void) frac;
+ (void) indx;
+ (void) index;
+#endif
+#ifdef DO_SPEC
+ specRed = solve_plane_chan(fx, fy, line->srPlane);
+ specGreen = solve_plane_chan(fx, fy, line->sgPlane);
+ specBlue = solve_plane_chan(fx, fy, line->sbPlane);
+#else
+ (void) specRed;
+ (void) specGreen;
+ (void) specBlue;
+#endif
+#ifdef DO_TEX
+ {
+ GLfloat invQ = solve_plane_recip(fx, fy, line->vPlane[0]);
+ tex[0][0] = solve_plane(fx, fy, line->sPlane[0]) * invQ;
+ tex[0][1] = solve_plane(fx, fy, line->tPlane[0]) * invQ;
+ tex[0][2] = solve_plane(fx, fy, line->uPlane[0]) * invQ;
+ lambda[0] = compute_lambda(line->sPlane[0], line->tPlane[0], invQ,
+ line->texWidth[0], line->texHeight[0]);
+ }
+#elif defined(DO_MULTITEX)
+ {
+ GLuint unit;
+ for (unit = 0; unit < ctx->Const.MaxTextureUnits; unit++) {
+ if (ctx->Texture.Unit[unit]._ReallyEnabled) {
+ GLfloat invQ = solve_plane_recip(fx, fy, line->vPlane[unit]);
+ tex[unit][0] = solve_plane(fx, fy, line->sPlane[unit]) * invQ;
+ tex[unit][1] = solve_plane(fx, fy, line->tPlane[unit]) * invQ;
+ tex[unit][2] = solve_plane(fx, fy, line->uPlane[unit]) * invQ;
+ lambda[unit] = compute_lambda(line->sPlane[unit],
+ line->tPlane[unit], invQ,
+ line->texWidth[unit], line->texHeight[unit]);
+ }
+ }
+ }
+#else
+ (void) tex[0][0];
+ (void) lambda[0];
+#endif
+
+
+#if defined(DO_MULTITEX)
+#if defined(DO_SPEC)
+ PB_WRITE_MULTITEX_SPEC_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha,
+ specRed, specGreen, specBlue, tex);
+#else
+ PB_WRITE_MULTITEX_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha, texcoords);
+#endif
+#elif defined(DO_TEX)
+ PB_WRITE_TEX_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha,
+ tex[0][0], tex[0][1], tex[0][2]);
+#elif defined(DO_RGBA)
+ PB_WRITE_RGBA_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha);
+#elif defined(DO_INDEX)
+ PB_WRITE_CI_PIXEL(pb, ix, iy, z, fog, index);
+#endif
+
+ PB_CHECK_FLUSH(ctx, pb);
+}
+
+
+
+/*
+ * Line setup
+ */
+static void
+NAME(line)(GLcontext *ctx, SWvertex *v0, SWvertex *v1)
+{
+ SWcontext *swrast = SWRAST_CONTEXT(ctx);
+ struct pixel_buffer *pb = SWRAST_CONTEXT(ctx)->PB;
+ GLfloat tStart, tEnd; /* segment start, end along line length */
+ GLboolean inSegment;
+ GLint iLen, i;
+
+ /* Init the LineInfo struct */
+ struct LineInfo line;
+ line.x0 = v0->win[0];
+ line.y0 = v0->win[1];
+ line.x1 = v1->win[0];
+ line.y1 = v1->win[1];
+ line.dx = line.x1 - line.x0;
+ line.dy = line.y1 - line.y0;
+ line.len = sqrt(line.dx * line.dx + line.dy * line.dy);
+ line.halfWidth = 0.5F * ctx->Line.Width;
+ line.xAdj = line.dx / line.len * line.halfWidth;
+ line.yAdj = line.dy / line.len * line.halfWidth;
+
+#ifdef DO_Z
+ compute_plane(line.x0, line.y0, line.x1, line.y1,
+ v0->win[2], v1->win[2], line.zPlane);
+#endif
+#ifdef DO_FOG
+ compute_plane(line.x0, line.y0, line.x1, line.y1,
+ v0->fog, v1->fog, line.fPlane);
+#endif
+#ifdef DO_RGBA
+ if (ctx->Light.ShadeModel == GL_SMOOTH) {
+ compute_plane(line.x0, line.y0, line.x1, line.y1,
+ v0->color[RCOMP], v1->color[RCOMP], line.rPlane);
+ compute_plane(line.x0, line.y0, line.x1, line.y1,
+ v0->color[GCOMP], v1->color[GCOMP], line.gPlane);
+ compute_plane(line.x0, line.y0, line.x1, line.y1,
+ v0->color[BCOMP], v1->color[BCOMP], line.bPlane);
+ compute_plane(line.x0, line.y0, line.x1, line.y1,
+ v0->color[ACOMP], v1->color[ACOMP], line.aPlane);
+ }
+ else {
+ constant_plane(v0->color[RCOMP], line.rPlane);
+ constant_plane(v0->color[GCOMP], line.gPlane);
+ constant_plane(v0->color[BCOMP], line.bPlane);
+ constant_plane(v0->color[ACOMP], line.aPlane);
+ }
+#endif
+#ifdef DO_SPEC
+ if (ctx->Light.ShadeModel == GL_SMOOTH) {
+ compute_plane(line.x0, line.y0, line.x1, line.y1,
+ v0->specular[RCOMP], v1->specular[RCOMP], line.srPlane);
+ compute_plane(line.x0, line.y0, line.x1, line.y1,
+ v0->specular[GCOMP], v1->specular[GCOMP], line.sgPlane);
+ compute_plane(line.x0, line.y0, line.x1, line.y1,
+ v0->specular[BCOMP], v1->specular[BCOMP], line.sbPlane);
+ }
+ else {
+ constant_plane(v0->specular[RCOMP], line.srPlane);
+ constant_plane(v0->specular[GCOMP], line.sgPlane);
+ constant_plane(v0->specular[BCOMP], line.sbPlane);
+ }
+#endif
+#ifdef DO_INDEX
+ if (ctx->Light.ShadeModel == GL_SMOOTH) {
+ compute_plane(line.x0, line.y0, line.x1, line.y1,
+ v0->index, v1->index, line.iPlane);
+ }
+ else {
+ constant_plane(v0->index, line.iPlane);
+ }
+#endif
+#ifdef DO_TEX
+ {
+ const struct gl_texture_object *obj = ctx->Texture.Unit[0]._Current;
+ const struct gl_texture_image *texImage = obj->Image[obj->BaseLevel];
+ const GLfloat invW0 = v0->win[3];
+ const GLfloat invW1 = v1->win[3];
+ const GLfloat s0 = v0->texcoord[0][0] * invW0;
+ const GLfloat s1 = v1->texcoord[0][0] * invW1;
+ const GLfloat t0 = v0->texcoord[0][1] * invW0;
+ const GLfloat t1 = v1->texcoord[0][1] * invW0;
+ const GLfloat r0 = v0->texcoord[0][2] * invW0;
+ const GLfloat r1 = v1->texcoord[0][2] * invW0;
+ const GLfloat q0 = v0->texcoord[0][3] * invW0;
+ const GLfloat q1 = v1->texcoord[0][3] * invW0;
+ compute_plane(line.x0, line.y0, line.x1, line.y1, s0, s1, line.sPlane[0]);
+ compute_plane(line.x0, line.y0, line.x1, line.y1, t0, t1, line.tPlane[0]);
+ compute_plane(line.x0, line.y0, line.x1, line.y1, r0, r1, line.uPlane[0]);
+ compute_plane(line.x0, line.y0, line.x1, line.y1, q0, q1, line.vPlane[0]);
+ line.texWidth[0] = (GLfloat) texImage->Width;
+ line.texHeight[0] = (GLfloat) texImage->Height;
+ }
+#elif defined(DO_MULITEX)
+ {
+ GLuint u;
+ for (u = 0; u < ctx->Const.MaxTextureUnits; u++) {
+ if (ctx->Texture.Unit[u].ReallyEnabled) {
+ const struct gl_texture_object *obj = ctx->Texture.Unit[u].Current;
+ const struct gl_texture_image *texImage = obj->Image[obj->BaseLevel];
+ const GLfloat invW0 = v0->win[3];
+ const GLfloat invW1 = v1->win[3];
+ GLfloat (*texCoord)[4] = VB->TexCoordPtr[u]->data;
+ const GLfloat s0 = v0->texcoord[u][0] * invW0;
+ const GLfloat s1 = v1->texcoord[u][0] * invW1;
+ const GLfloat t0 = v0->texcoord[u][1] * invW0;
+ const GLfloat t1 = v1->texcoord[u][1] * invW0;
+ const GLfloat r0 = v0->texcoord[u][2] * invW0;
+ const GLfloat r1 = v1->texcoord[u][2] * invW0;
+ const GLfloat q0 = v0->texcoord[u][3] * invW0;
+ const GLfloat q1 = v1->texcoord[u][3] * invW0;
+ compute_plane(line.x0, line.y0, line.x1, line.y1, s0, s1, line.sPlane[u]);
+ compute_plane(line.x0, line.y0, line.x1, line.y1, t0, t1, line.tPlane[u]);
+ compute_plane(line.x0, line.y0, line.x1, line.y1, u0, u1, line.uPlane[u]);
+ compute_plane(line.x0, line.y0, line.x1, line.y1, v0, v1, line.vPlane[u]);
+ line.texWidth[u] = (GLfloat) texImage->Width;
+ line.texHeight[u] = (GLfloat) texImage->Height;
+ }
+ }
+ }
+#endif
+
+ tStart = tEnd = 0.0;
+ inSegment = GL_FALSE;
+ iLen = (GLint) line.len;
+
+ if (ctx->Line.StippleFlag) {
+ for (i = 0; i < iLen; i++) {
+ const GLuint bit = (swrast->StippleCounter / ctx->Line.StippleFactor) & 0xf;
+ if ((1 << bit) & ctx->Line.StipplePattern) {
+ /* stipple bit is on */
+ const GLfloat t = (GLfloat) i / (GLfloat) line.len;
+ if (!inSegment) {
+ /* start new segment */
+ inSegment = GL_TRUE;
+ tStart = t;
+ }
+ else {
+ /* still in the segment, extend it */
+ tEnd = t;
+ }
+ }
+ else {
+ /* stipple bit is off */
+ if (inSegment && (tEnd > tStart)) {
+ /* draw the segment */
+ segment(ctx, &line, NAME(plot), pb, tStart, tEnd);
+ inSegment = GL_FALSE;
+ }
+ else {
+ /* still between segments, do nothing */
+ }
+ }
+ swrast->StippleCounter++;
+ }
+ }
+ else {
+ /* non-stippled */
+ segment(ctx, &line, NAME(plot), pb, 0.0, 1.0);
+ }
+}
+
+
+
+
+#undef DO_Z
+#undef DO_FOG
+#undef DO_RGBA
+#undef DO_INDEX
+#undef DO_SPEC
+#undef DO_TEX
+#undef DO_MULTITEX
+#undef NAME
projects / mesa.git / commitdiff