/* $Id: s_aatritemp.h,v 1.21.2.1 2001/12/05 10:22:55 keithw Exp $ */ /* * Mesa 3-D graphics library * Version: 3.5 * * Copyright (C) 1999-2001 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 Triangle Rasterizer Template * * This file is #include'd to generate custom AA triangle rasterizers. * NOTE: this code hasn't been optimized yet. That'll come after it * works correctly. * * The following macros may be defined to indicate what auxillary information * must be copmuted across the triangle: * DO_Z - if defined, compute Z values * DO_RGBA - if defined, compute RGBA values * DO_INDEX - if defined, compute color index values * DO_SPEC - if defined, compute specular RGB values * DO_TEX - if defined, compute unit 0 STRQ texcoords * DO_MULTITEX - if defined, compute all unit's STRQ texcoords */ /*void triangle( GLcontext *ctx, GLuint v0, GLuint v1, GLuint v2, GLuint pv )*/ { const GLfloat *p0 = v0->win; const GLfloat *p1 = v1->win; const GLfloat *p2 = v2->win; const SWvertex *vMin, *vMid, *vMax; GLint iyMin, iyMax; GLfloat yMin, yMax; GLboolean ltor; GLfloat majDx, majDy; /* major (i.e. long) edge dx and dy */ #ifdef DO_Z GLfloat zPlane[4]; GLdepth z[MAX_WIDTH]; #endif #ifdef DO_FOG GLfloat fogPlane[4]; GLfloat fog[MAX_WIDTH]; #else GLfloat *fog = NULL; #endif #ifdef DO_RGBA GLfloat rPlane[4], gPlane[4], bPlane[4], aPlane[4]; DEFMARRAY(GLchan, rgba, MAX_WIDTH, 4); /* mac 32k limitation */ #endif #ifdef DO_INDEX GLfloat iPlane[4]; GLuint index[MAX_WIDTH]; GLint icoverageSpan[MAX_WIDTH]; #else GLfloat coverageSpan[MAX_WIDTH]; #endif #ifdef DO_SPEC GLfloat srPlane[4], sgPlane[4], sbPlane[4]; DEFMARRAY(GLchan, spec, MAX_WIDTH, 4); #endif #ifdef DO_TEX GLfloat sPlane[4], tPlane[4], uPlane[4], vPlane[4]; GLfloat texWidth, texHeight; DEFARRAY(GLfloat, s, MAX_WIDTH); /* mac 32k limitation */ DEFARRAY(GLfloat, t, MAX_WIDTH); DEFARRAY(GLfloat, u, MAX_WIDTH); DEFARRAY(GLfloat, lambda, MAX_WIDTH); #elif defined(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 texWidth[MAX_TEXTURE_UNITS], texHeight[MAX_TEXTURE_UNITS]; DEFMARRAY(GLfloat, s, MAX_TEXTURE_UNITS, MAX_WIDTH); /* mac 32k limit */ DEFMARRAY(GLfloat, t, MAX_TEXTURE_UNITS, MAX_WIDTH); DEFMARRAY(GLfloat, u, MAX_TEXTURE_UNITS, MAX_WIDTH); DEFMARRAY(GLfloat, lambda, MAX_TEXTURE_UNITS, MAX_WIDTH); #endif GLfloat bf = SWRAST_CONTEXT(ctx)->_backface_sign; #ifdef DO_RGBA CHECKARRAY(rgba, return); /* mac 32k limitation */ #endif #ifdef DO_SPEC CHECKARRAY(spec, return); #endif #if defined(DO_TEX) || defined(DO_MULTITEX) CHECKARRAY(s, return); CHECKARRAY(t, return); CHECKARRAY(u, return); CHECKARRAY(lambda, return); #endif /* determine bottom to top order of vertices */ { GLfloat y0 = v0->win[1]; GLfloat y1 = v1->win[1]; GLfloat y2 = v2->win[1]; if (y0 <= y1) { if (y1 <= y2) { vMin = v0; vMid = v1; vMax = v2; /* y0<=y1<=y2 */ } else if (y2 <= y0) { vMin = v2; vMid = v0; vMax = v1; /* y2<=y0<=y1 */ } else { vMin = v0; vMid = v2; vMax = v1; bf = -bf; /* y0<=y2<=y1 */ } } else { if (y0 <= y2) { vMin = v1; vMid = v0; vMax = v2; bf = -bf; /* y1<=y0<=y2 */ } else if (y2 <= y1) { vMin = v2; vMid = v1; vMax = v0; bf = -bf; /* y2<=y1<=y0 */ } else { vMin = v1; vMid = v2; vMax = v0; /* y1<=y2<=y0 */ } } } majDx = vMax->win[0] - vMin->win[0]; majDy = vMax->win[1] - vMin->win[1]; { const GLfloat botDx = vMid->win[0] - vMin->win[0]; const GLfloat botDy = vMid->win[1] - vMin->win[1]; const GLfloat area = majDx * botDy - botDx * majDy; ltor = (GLboolean) (area < 0.0F); /* Do backface culling */ if (area * bf < 0 || area == 0 || IS_INF_OR_NAN(area)) return; } #ifndef DO_OCCLUSION_TEST ctx->OcclusionResult = GL_TRUE; #endif /* Plane equation setup: * We evaluate plane equations at window (x,y) coordinates in order * to compute color, Z, fog, texcoords, etc. This isn't terribly * efficient but it's easy and reliable. */ #ifdef DO_Z compute_plane(p0, p1, p2, p0[2], p1[2], p2[2], zPlane); #endif #ifdef DO_FOG compute_plane(p0, p1, p2, v0->fog, v1->fog, v2->fog, fogPlane); #endif #ifdef DO_RGBA if (ctx->Light.ShadeModel == GL_SMOOTH) { compute_plane(p0, p1, p2, v0->color[0], v1->color[0], v2->color[0], rPlane); compute_plane(p0, p1, p2, v0->color[1], v1->color[1], v2->color[1], gPlane); compute_plane(p0, p1, p2, v0->color[2], v1->color[2], v2->color[2], bPlane); compute_plane(p0, p1, p2, v0->color[3], v1->color[3], v2->color[3], aPlane); } else { constant_plane(v2->color[RCOMP], rPlane); constant_plane(v2->color[GCOMP], gPlane); constant_plane(v2->color[BCOMP], bPlane); constant_plane(v2->color[ACOMP], aPlane); } #endif #ifdef DO_INDEX if (ctx->Light.ShadeModel == GL_SMOOTH) { compute_plane(p0, p1, p2, (GLfloat) v0->index, (GLfloat) v1->index, (GLfloat) v2->index, iPlane); } else { constant_plane((GLfloat) v2->index, iPlane); } #endif #ifdef DO_SPEC if (ctx->Light.ShadeModel == GL_SMOOTH) { compute_plane(p0, p1, p2, v0->specular[0], v1->specular[0], v2->specular[0],srPlane); compute_plane(p0, p1, p2, v0->specular[1], v1->specular[1], v2->specular[1],sgPlane); compute_plane(p0, p1, p2, v0->specular[2], v1->specular[2], v2->specular[2],sbPlane); } else { constant_plane(v2->specular[RCOMP], srPlane); constant_plane(v2->specular[GCOMP], sgPlane); constant_plane(v2->specular[BCOMP], sbPlane); } #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 invW2 = v2->win[3]; const GLfloat s0 = v0->texcoord[0][0] * invW0; const GLfloat s1 = v1->texcoord[0][0] * invW1; const GLfloat s2 = v2->texcoord[0][0] * invW2; const GLfloat t0 = v0->texcoord[0][1] * invW0; const GLfloat t1 = v1->texcoord[0][1] * invW1; const GLfloat t2 = v2->texcoord[0][1] * invW2; const GLfloat r0 = v0->texcoord[0][2] * invW0; const GLfloat r1 = v1->texcoord[0][2] * invW1; const GLfloat r2 = v2->texcoord[0][2] * invW2; const GLfloat q0 = v0->texcoord[0][3] * invW0; const GLfloat q1 = v1->texcoord[0][3] * invW1; const GLfloat q2 = v2->texcoord[0][3] * invW2; compute_plane(p0, p1, p2, s0, s1, s2, sPlane); compute_plane(p0, p1, p2, t0, t1, t2, tPlane); compute_plane(p0, p1, p2, r0, r1, r2, uPlane); compute_plane(p0, p1, p2, q0, q1, q2, vPlane); texWidth = (GLfloat) texImage->Width; texHeight = (GLfloat) texImage->Height; } #elif defined(DO_MULTITEX) { 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]; const GLfloat invW2 = v2->win[3]; const GLfloat s0 = v0->texcoord[u][0] * invW0; const GLfloat s1 = v1->texcoord[u][0] * invW1; const GLfloat s2 = v2->texcoord[u][0] * invW2; const GLfloat t0 = v0->texcoord[u][1] * invW0; const GLfloat t1 = v1->texcoord[u][1] * invW1; const GLfloat t2 = v2->texcoord[u][1] * invW2; const GLfloat r0 = v0->texcoord[u][2] * invW0; const GLfloat r1 = v1->texcoord[u][2] * invW1; const GLfloat r2 = v2->texcoord[u][2] * invW2; const GLfloat q0 = v0->texcoord[u][3] * invW0; const GLfloat q1 = v1->texcoord[u][3] * invW1; const GLfloat q2 = v2->texcoord[u][3] * invW2; compute_plane(p0, p1, p2, s0, s1, s2, sPlane[u]); compute_plane(p0, p1, p2, t0, t1, t2, tPlane[u]); compute_plane(p0, p1, p2, r0, r1, r2, uPlane[u]); compute_plane(p0, p1, p2, q0, q1, q2, vPlane[u]); texWidth[u] = (GLfloat) texImage->Width; texHeight[u] = (GLfloat) texImage->Height; } } } #endif /* Begin bottom-to-top scan over the triangle. * The long edge will either be on the left or right side of the * triangle. We always scan from the long edge toward the shorter * edges, stopping when we find that coverage = 0. If the long edge * is on the left we scan left-to-right. Else, we scan right-to-left. */ yMin = vMin->win[1]; yMax = vMax->win[1]; iyMin = (GLint) yMin; iyMax = (GLint) yMax + 1; if (ltor) { /* scan left to right */ const GLfloat *pMin = vMin->win; const GLfloat *pMid = vMid->win; const GLfloat *pMax = vMax->win; const GLfloat dxdy = majDx / majDy; const GLfloat xAdj = dxdy < 0.0F ? -dxdy : 0.0F; GLfloat x = pMin[0] - (yMin - iyMin) * dxdy; GLint iy; for (iy = iyMin; iy < iyMax; iy++, x += dxdy) { GLint ix, startX = (GLint) (x - xAdj); GLuint count, n; GLfloat coverage = 0.0F; /* skip over fragments with zero coverage */ while (startX < MAX_WIDTH) { coverage = compute_coveragef(pMin, pMid, pMax, startX, iy); if (coverage > 0.0F) break; startX++; } /* enter interior of triangle */ ix = startX; count = 0; while (coverage > 0.0F) { /* (cx,cy) = center of fragment */ const GLfloat cx = ix + 0.5F, cy = iy + 0.5F; #ifdef DO_INDEX icoverageSpan[count] = compute_coveragei(pMin, pMid, pMax, ix, iy); #else coverageSpan[count] = coverage; #endif #ifdef DO_Z z[count] = (GLdepth) solve_plane(cx, cy, zPlane); #endif #ifdef DO_FOG fog[count] = solve_plane(cx, cy, fogPlane); #endif #ifdef DO_RGBA rgba[count][RCOMP] = solve_plane_chan(cx, cy, rPlane); rgba[count][GCOMP] = solve_plane_chan(cx, cy, gPlane); rgba[count][BCOMP] = solve_plane_chan(cx, cy, bPlane); rgba[count][ACOMP] = solve_plane_chan(cx, cy, aPlane); #endif #ifdef DO_INDEX index[count] = (GLint) solve_plane(cx, cy, iPlane); #endif #ifdef DO_SPEC spec[count][RCOMP] = solve_plane_chan(cx, cy, srPlane); spec[count][GCOMP] = solve_plane_chan(cx, cy, sgPlane); spec[count][BCOMP] = solve_plane_chan(cx, cy, sbPlane); #endif #ifdef DO_TEX { const GLfloat invQ = solve_plane_recip(cx, cy, vPlane); s[count] = solve_plane(cx, cy, sPlane) * invQ; t[count] = solve_plane(cx, cy, tPlane) * invQ; u[count] = solve_plane(cx, cy, uPlane) * invQ; lambda[count] = compute_lambda(sPlane, tPlane, invQ, texWidth, texHeight); } #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(cx, cy, vPlane[unit]); s[unit][count] = solve_plane(cx, cy, sPlane[unit]) * invQ; t[unit][count] = solve_plane(cx, cy, tPlane[unit]) * invQ; u[unit][count] = solve_plane(cx, cy, uPlane[unit]) * invQ; lambda[unit][count] = compute_lambda(sPlane[unit], tPlane[unit], invQ, texWidth[unit], texHeight[unit]); } } } #endif ix++; count++; coverage = compute_coveragef(pMin, pMid, pMax, ix, iy); } if (ix <= startX) continue; n = (GLuint) ix - (GLuint) startX; #ifdef DO_MULTITEX # ifdef DO_SPEC _mesa_write_multitexture_span(ctx, n, startX, iy, z, fog, (const GLfloat (*)[MAX_WIDTH]) s, (const GLfloat (*)[MAX_WIDTH]) t, (const GLfloat (*)[MAX_WIDTH]) u, (GLfloat (*)[MAX_WIDTH]) lambda, rgba, (const GLchan (*)[4]) spec, coverageSpan, GL_POLYGON); # else _mesa_write_multitexture_span(ctx, n, startX, iy, z, fog, (const GLfloat (*)[MAX_WIDTH]) s, (const GLfloat (*)[MAX_WIDTH]) t, (const GLfloat (*)[MAX_WIDTH]) u, lambda, rgba, NULL, coverageSpan, GL_POLYGON); # endif #elif defined(DO_TEX) # ifdef DO_SPEC _mesa_write_texture_span(ctx, n, startX, iy, z, fog, s, t, u, lambda, rgba, (const GLchan (*)[4]) spec, coverageSpan, GL_POLYGON); # else _mesa_write_texture_span(ctx, n, startX, iy, z, fog, s, t, u, lambda, rgba, NULL, coverageSpan, GL_POLYGON); # endif #elif defined(DO_RGBA) _mesa_write_rgba_span(ctx, n, startX, iy, z, fog, rgba, coverageSpan, GL_POLYGON); #elif defined(DO_INDEX) _mesa_write_index_span(ctx, n, startX, iy, z, fog, index, icoverageSpan, GL_POLYGON); #endif } } else { /* scan right to left */ const GLfloat *pMin = vMin->win; const GLfloat *pMid = vMid->win; const GLfloat *pMax = vMax->win; const GLfloat dxdy = majDx / majDy; const GLfloat xAdj = dxdy > 0 ? dxdy : 0.0F; GLfloat x = pMin[0] - (yMin - iyMin) * dxdy; GLint iy; for (iy = iyMin; iy < iyMax; iy++, x += dxdy) { GLint ix, left, startX = (GLint) (x + xAdj); GLuint count, n; GLfloat coverage = 0.0F; /* make sure we're not past the window edge */ if (startX >= ctx->DrawBuffer->_Xmax) { startX = ctx->DrawBuffer->_Xmax - 1; } /* skip fragments with zero coverage */ while (startX >= 0) { coverage = compute_coveragef(pMin, pMax, pMid, startX, iy); if (coverage > 0.0F) break; startX--; } /* enter interior of triangle */ ix = startX; count = 0; while (coverage > 0.0F) { /* (cx,cy) = center of fragment */ const GLfloat cx = ix + 0.5F, cy = iy + 0.5F; #ifdef DO_INDEX icoverageSpan[ix] = compute_coveragei(pMin, pMid, pMax, ix, iy); #else coverageSpan[ix] = coverage; #endif #ifdef DO_Z z[ix] = (GLdepth) solve_plane(cx, cy, zPlane); #endif #ifdef DO_FOG fog[ix] = solve_plane(cx, cy, fogPlane); #endif #ifdef DO_RGBA rgba[ix][RCOMP] = solve_plane_chan(cx, cy, rPlane); rgba[ix][GCOMP] = solve_plane_chan(cx, cy, gPlane); rgba[ix][BCOMP] = solve_plane_chan(cx, cy, bPlane); rgba[ix][ACOMP] = solve_plane_chan(cx, cy, aPlane); #endif #ifdef DO_INDEX index[ix] = (GLint) solve_plane(cx, cy, iPlane); #endif #ifdef DO_SPEC spec[ix][RCOMP] = solve_plane_chan(cx, cy, srPlane); spec[ix][GCOMP] = solve_plane_chan(cx, cy, sgPlane); spec[ix][BCOMP] = solve_plane_chan(cx, cy, sbPlane); #endif #ifdef DO_TEX { const GLfloat invQ = solve_plane_recip(cx, cy, vPlane); s[ix] = solve_plane(cx, cy, sPlane) * invQ; t[ix] = solve_plane(cx, cy, tPlane) * invQ; u[ix] = solve_plane(cx, cy, uPlane) * invQ; lambda[ix] = compute_lambda(sPlane, tPlane, invQ, texWidth, texHeight); } #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(cx, cy, vPlane[unit]); s[unit][ix] = solve_plane(cx, cy, sPlane[unit]) * invQ; t[unit][ix] = solve_plane(cx, cy, tPlane[unit]) * invQ; u[unit][ix] = solve_plane(cx, cy, uPlane[unit]) * invQ; lambda[unit][ix] = compute_lambda(sPlane[unit], tPlane[unit], invQ, texWidth[unit], texHeight[unit]); } } } #endif ix--; count++; coverage = compute_coveragef(pMin, pMax, pMid, ix, iy); } if (startX <= ix) continue; n = (GLuint) startX - (GLuint) ix; left = ix + 1; #ifdef DO_MULTITEX { GLuint unit; for (unit = 0; unit < ctx->Const.MaxTextureUnits; unit++) { if (ctx->Texture.Unit[unit]._ReallyEnabled) { GLint j; for (j = 0; j < (GLint) n; j++) { s[unit][j] = s[unit][j + left]; t[unit][j] = t[unit][j + left]; u[unit][j] = u[unit][j + left]; lambda[unit][j] = lambda[unit][j + left]; } } } } # ifdef DO_SPEC _mesa_write_multitexture_span(ctx, n, left, iy, z + left, fog + left, (const GLfloat (*)[MAX_WIDTH]) s, (const GLfloat (*)[MAX_WIDTH]) t, (const GLfloat (*)[MAX_WIDTH]) u, lambda, rgba + left, (const GLchan (*)[4]) (spec + left), coverageSpan + left, GL_POLYGON); # else _mesa_write_multitexture_span(ctx, n, left, iy, z + left, fog + left, (const GLfloat (*)[MAX_WIDTH]) s, (const GLfloat (*)[MAX_WIDTH]) t, (const GLfloat (*)[MAX_WIDTH]) u, lambda, rgba + left, NULL, coverageSpan + left, GL_POLYGON); # endif #elif defined(DO_TEX) # ifdef DO_SPEC _mesa_write_texture_span(ctx, n, left, iy, z + left, fog + left, s + left, t + left, u + left, lambda + left, rgba + left, (const GLchan (*)[4]) (spec + left), coverageSpan + left, GL_POLYGON); # else _mesa_write_texture_span(ctx, n, left, iy, z + left, fog + left, s + left, t + left, u + left, lambda + left, rgba + left, NULL, coverageSpan + left, GL_POLYGON); # endif #elif defined(DO_RGBA) _mesa_write_rgba_span(ctx, n, left, iy, z + left, fog + left, rgba + left, coverageSpan + left, GL_POLYGON); #elif defined(DO_INDEX) _mesa_write_index_span(ctx, n, left, iy, z + left, fog + left, index + left, icoverageSpan + left, GL_POLYGON); #endif } } #ifdef DO_RGBA UNDEFARRAY(rgba); /* mac 32k limitation */ #endif #ifdef DO_SPEC UNDEFARRAY(spec); #endif #if defined(DO_TEX) || defined(DO_MULTITEX) UNDEFARRAY(s); UNDEFARRAY(t); UNDEFARRAY(u); UNDEFARRAY(lambda); #endif } #ifdef DO_Z #undef DO_Z #endif #ifdef DO_FOG #undef DO_FOG #endif #ifdef DO_RGBA #undef DO_RGBA #endif #ifdef DO_INDEX #undef DO_INDEX #endif #ifdef DO_SPEC #undef DO_SPEC #endif #ifdef DO_TEX #undef DO_TEX #endif #ifdef DO_MULTITEX #undef DO_MULTITEX #endif #ifdef DO_OCCLUSION_TEST #undef DO_OCCLUSION_TEST #endif