/* $Id: s_tritemp.h,v 1.35 2002/03/16 18:02:08 brianp 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. */ /* $XFree86: xc/extras/Mesa/src/swrast/s_tritemp.h,v 1.2 2002/02/27 21:07:54 tsi Exp $ */ /* * Triangle Rasterizer Template * * This file is #include'd to generate custom triangle rasterizers. * * The following macros may be defined to indicate what auxillary information * must be interplated across the triangle: * INTERP_Z - if defined, interpolate Z values * INTERP_FOG - if defined, interpolate fog values * INTERP_RGB - if defined, interpolate RGB values * INTERP_ALPHA - if defined, interpolate Alpha values (req's INTERP_RGB) * INTERP_SPEC - if defined, interpolate specular RGB values * INTERP_INDEX - if defined, interpolate color index values * INTERP_INT_TEX - if defined, interpolate integer ST texcoords * (fast, simple 2-D texture mapping) * INTERP_TEX - if defined, interpolate set 0 float STRQ texcoords * NOTE: OpenGL STRQ = Mesa STUV (R was taken for red) * INTERP_MULTITEX - if defined, interpolate N units of STRQ texcoords * INTERP_FLOAT_RGBA - if defined, interpolate RGBA with floating point * INTERP_FLOAT_SPEC - if defined, interpolate specular with floating point * * When one can directly address pixels in the color buffer the following * macros can be defined and used to compute pixel addresses during * rasterization (see pRow): * PIXEL_TYPE - the datatype of a pixel (GLubyte, GLushort, GLuint) * BYTES_PER_ROW - number of bytes per row in the color buffer * PIXEL_ADDRESS(X,Y) - returns the address of pixel at (X,Y) where * Y==0 at bottom of screen and increases upward. * * Similarly, for direct depth buffer access, this type is used for depth * buffer addressing: * DEPTH_TYPE - either GLushort or GLuint * * Optionally, one may provide one-time setup code per triangle: * SETUP_CODE - code which is to be executed once per triangle * CLEANUP_CODE - code to execute at end of triangle * * The following macro MUST be defined: * RENDER_SPAN(span) - code to write a span of pixels. * * This code was designed for the origin to be in the lower-left corner. * * Inspired by triangle rasterizer code written by Allen Akin. Thanks Allen! */ /* * This is a bit of a hack, but it's a centralized place to enable floating- * point color interpolation when GLchan is actually floating point. */ #if CHAN_TYPE == GL_FLOAT #if defined(INTERP_RGB) #undef INTERP_RGB #undef INTERP_ALPHA #define INTERP_FLOAT_RGBA #endif #if defined(INTERP_SPEC) #undef INTERP_SPEC #define INTERP_FLOAT_SPEC #endif #endif /*void triangle( GLcontext *ctx, SWvertex *v0, SWvertex *v1, SWvertex *v2 )*/ { typedef struct { const SWvertex *v0, *v1; /* Y(v0) < Y(v1) */ GLfloat dx; /* X(v1) - X(v0) */ GLfloat dy; /* Y(v1) - Y(v0) */ GLfixed fdxdy; /* dx/dy in fixed-point */ GLfixed fsx; /* first sample point x coord */ GLfixed fsy; GLfloat adjy; /* adjust from v[0]->fy to fsy, scaled */ GLint lines; /* number of lines to be sampled on this edge */ GLfixed fx0; /* fixed pt X of lower endpoint */ } EdgeT; #ifdef INTERP_Z const GLint depthBits = ctx->Visual.depthBits; const GLint fixedToDepthShift = depthBits <= 16 ? FIXED_SHIFT : 0; const GLfloat maxDepth = ctx->DepthMaxF; #define FixedToDepth(F) ((F) >> fixedToDepthShift) #endif EdgeT eMaj, eTop, eBot; GLfloat oneOverArea; const SWvertex *vMin, *vMid, *vMax; /* Y(vMin)<=Y(vMid)<=Y(vMax) */ float bf = SWRAST_CONTEXT(ctx)->_backface_sign; const GLint snapMask = ~((FIXED_ONE / 16) - 1); /* for x/y coord snapping */ GLfixed vMin_fx, vMin_fy, vMid_fx, vMid_fy, vMax_fx, vMax_fy; struct sw_span span; INIT_SPAN(span); #ifdef INTERP_Z (void) fixedToDepthShift; #endif /* printf("%s()\n", __FUNCTION__); printf(" %g, %g, %g\n", v0->win[0], v0->win[1], v0->win[2]); printf(" %g, %g, %g\n", v1->win[0], v1->win[1], v1->win[2]); printf(" %g, %g, %g\n", v2->win[0], v2->win[1], v2->win[2]); */ /* Compute fixed point x,y coords w/ half-pixel offsets and snapping. * And find the order of the 3 vertices along the Y axis. */ { const GLfixed fy0 = FloatToFixed(v0->win[1] - 0.5F) & snapMask; const GLfixed fy1 = FloatToFixed(v1->win[1] - 0.5F) & snapMask; const GLfixed fy2 = FloatToFixed(v2->win[1] - 0.5F) & snapMask; if (fy0 <= fy1) { if (fy1 <= fy2) { /* y0 <= y1 <= y2 */ vMin = v0; vMid = v1; vMax = v2; vMin_fy = fy0; vMid_fy = fy1; vMax_fy = fy2; } else if (fy2 <= fy0) { /* y2 <= y0 <= y1 */ vMin = v2; vMid = v0; vMax = v1; vMin_fy = fy2; vMid_fy = fy0; vMax_fy = fy1; } else { /* y0 <= y2 <= y1 */ vMin = v0; vMid = v2; vMax = v1; vMin_fy = fy0; vMid_fy = fy2; vMax_fy = fy1; bf = -bf; } } else { if (fy0 <= fy2) { /* y1 <= y0 <= y2 */ vMin = v1; vMid = v0; vMax = v2; vMin_fy = fy1; vMid_fy = fy0; vMax_fy = fy2; bf = -bf; } else if (fy2 <= fy1) { /* y2 <= y1 <= y0 */ vMin = v2; vMid = v1; vMax = v0; vMin_fy = fy2; vMid_fy = fy1; vMax_fy = fy0; bf = -bf; } else { /* y1 <= y2 <= y0 */ vMin = v1; vMid = v2; vMax = v0; vMin_fy = fy1; vMid_fy = fy2; vMax_fy = fy0; } } /* fixed point X coords */ vMin_fx = FloatToFixed(vMin->win[0] + 0.5F) & snapMask; vMid_fx = FloatToFixed(vMid->win[0] + 0.5F) & snapMask; vMax_fx = FloatToFixed(vMax->win[0] + 0.5F) & snapMask; } /* vertex/edge relationship */ eMaj.v0 = vMin; eMaj.v1 = vMax; /*TODO: .v1's not needed */ eTop.v0 = vMid; eTop.v1 = vMax; eBot.v0 = vMin; eBot.v1 = vMid; /* compute deltas for each edge: vertex[upper] - vertex[lower] */ eMaj.dx = FixedToFloat(vMax_fx - vMin_fx); eMaj.dy = FixedToFloat(vMax_fy - vMin_fy); eTop.dx = FixedToFloat(vMax_fx - vMid_fx); eTop.dy = FixedToFloat(vMax_fy - vMid_fy); eBot.dx = FixedToFloat(vMid_fx - vMin_fx); eBot.dy = FixedToFloat(vMid_fy - vMin_fy); /* compute area, oneOverArea and perform backface culling */ { const GLfloat area = eMaj.dx * eBot.dy - eBot.dx * eMaj.dy; /* Do backface culling */ if (area * bf < 0.0) return; if (area == 0.0F || IS_INF_OR_NAN(area)) return; oneOverArea = 1.0F / area; } #ifndef DO_OCCLUSION_TEST ctx->OcclusionResult = GL_TRUE; #endif /* Edge setup. For a triangle strip these could be reused... */ { eMaj.fsy = FixedCeil(vMin_fy); eMaj.lines = FixedToInt(FixedCeil(vMax_fy - eMaj.fsy)); if (eMaj.lines > 0) { GLfloat dxdy = eMaj.dx / eMaj.dy; eMaj.fdxdy = SignedFloatToFixed(dxdy); eMaj.adjy = (GLfloat) (eMaj.fsy - vMin_fy); /* SCALED! */ eMaj.fx0 = vMin_fx; eMaj.fsx = eMaj.fx0 + (GLfixed) (eMaj.adjy * dxdy); } else { return; /*CULLED*/ } eTop.fsy = FixedCeil(vMid_fy); eTop.lines = FixedToInt(FixedCeil(vMax_fy - eTop.fsy)); if (eTop.lines > 0) { GLfloat dxdy = eTop.dx / eTop.dy; eTop.fdxdy = SignedFloatToFixed(dxdy); eTop.adjy = (GLfloat) (eTop.fsy - vMid_fy); /* SCALED! */ eTop.fx0 = vMid_fx; eTop.fsx = eTop.fx0 + (GLfixed) (eTop.adjy * dxdy); } eBot.fsy = FixedCeil(vMin_fy); eBot.lines = FixedToInt(FixedCeil(vMid_fy - eBot.fsy)); if (eBot.lines > 0) { GLfloat dxdy = eBot.dx / eBot.dy; eBot.fdxdy = SignedFloatToFixed(dxdy); eBot.adjy = (GLfloat) (eBot.fsy - vMin_fy); /* SCALED! */ eBot.fx0 = vMin_fx; eBot.fsx = eBot.fx0 + (GLfixed) (eBot.adjy * dxdy); } } /* * Conceptually, we view a triangle as two subtriangles * separated by a perfectly horizontal line. The edge that is * intersected by this line is one with maximal absolute dy; we * call it a ``major'' edge. The other two edges are the * ``top'' edge (for the upper subtriangle) and the ``bottom'' * edge (for the lower subtriangle). If either of these two * edges is horizontal or very close to horizontal, the * corresponding subtriangle might cover zero sample points; * we take care to handle such cases, for performance as well * as correctness. * * By stepping rasterization parameters along the major edge, * we can avoid recomputing them at the discontinuity where * the top and bottom edges meet. However, this forces us to * be able to scan both left-to-right and right-to-left. * Also, we must determine whether the major edge is at the * left or right side of the triangle. We do this by * computing the magnitude of the cross-product of the major * and top edges. Since this magnitude depends on the sine of * the angle between the two edges, its sign tells us whether * we turn to the left or to the right when travelling along * the major edge to the top edge, and from this we infer * whether the major edge is on the left or the right. * * Serendipitously, this cross-product magnitude is also a * value we need to compute the iteration parameter * derivatives for the triangle, and it can be used to perform * backface culling because its sign tells us whether the * triangle is clockwise or counterclockwise. In this code we * refer to it as ``area'' because it's also proportional to * the pixel area of the triangle. */ { GLint scan_from_left_to_right; /* true if scanning left-to-right */ #ifdef INTERP_Z GLfloat dzdx, dzdy; #endif #ifdef INTERP_FOG GLfloat dfogdy; #endif #if defined(INTERP_RGB) || defined(INTERP_FLOAT_RGBA) GLfloat drdx, drdy; GLfloat dgdx, dgdy; GLfloat dbdx, dbdy; #endif #if defined(INTERP_ALPHA) || defined(INTERP_FLOAT_RGBA) GLfloat dadx, dady; #endif #if defined(INTERP_SPEC) || defined(INTERP_FLOAT_SPEC) GLfloat dsrdx, dsrdy; GLfloat dsgdx, dsgdy; GLfloat dsbdx, dsbdy; #endif #ifdef INTERP_INDEX GLfloat didx, didy; #endif #ifdef INTERP_INT_TEX GLfloat dsdx, dsdy; GLfloat dtdx, dtdy; #endif #ifdef INTERP_TEX GLfloat dsdx, dsdy; GLfloat dtdx, dtdy; GLfloat dudx, dudy; GLfloat dvdx, dvdy; #endif #ifdef INTERP_MULTITEX GLfloat dsdx[MAX_TEXTURE_UNITS], dsdy[MAX_TEXTURE_UNITS]; GLfloat dtdx[MAX_TEXTURE_UNITS], dtdy[MAX_TEXTURE_UNITS]; GLfloat dudx[MAX_TEXTURE_UNITS], dudy[MAX_TEXTURE_UNITS]; GLfloat dvdx[MAX_TEXTURE_UNITS], dvdy[MAX_TEXTURE_UNITS]; #endif /* * Execute user-supplied setup code */ #ifdef SETUP_CODE SETUP_CODE #endif scan_from_left_to_right = (oneOverArea < 0.0F); /* compute d?/dx and d?/dy derivatives */ #ifdef INTERP_Z span.interpMask |= SPAN_Z; { GLfloat eMaj_dz, eBot_dz; eMaj_dz = vMax->win[2] - vMin->win[2]; eBot_dz = vMid->win[2] - vMin->win[2]; dzdx = oneOverArea * (eMaj_dz * eBot.dy - eMaj.dy * eBot_dz); if (dzdx > maxDepth || dzdx < -maxDepth) { /* probably a sliver triangle */ dzdx = 0.0; dzdy = 0.0; } else { dzdy = oneOverArea * (eMaj.dx * eBot_dz - eMaj_dz * eBot.dx); } if (depthBits <= 16) span.zStep = SignedFloatToFixed(dzdx); else span.zStep = (GLint) dzdx; } #endif #ifdef INTERP_FOG span.interpMask |= SPAN_FOG; { const GLfloat eMaj_dfog = vMax->fog - vMin->fog; const GLfloat eBot_dfog = vMid->fog - vMin->fog; span.fogStep = oneOverArea * (eMaj_dfog * eBot.dy - eMaj.dy * eBot_dfog); dfogdy = oneOverArea * (eMaj.dx * eBot_dfog - eMaj_dfog * eBot.dx); } #endif #ifdef INTERP_RGB span.interpMask |= SPAN_RGBA; if (ctx->Light.ShadeModel == GL_SMOOTH) { GLfloat eMaj_dr, eBot_dr; GLfloat eMaj_dg, eBot_dg; GLfloat eMaj_db, eBot_db; # ifdef INTERP_ALPHA GLfloat eMaj_da, eBot_da; # endif eMaj_dr = (GLfloat) ((GLint) vMax->color[RCOMP] - (GLint) vMin->color[RCOMP]); eBot_dr = (GLfloat) ((GLint) vMid->color[RCOMP] - (GLint) vMin->color[RCOMP]); drdx = oneOverArea * (eMaj_dr * eBot.dy - eMaj.dy * eBot_dr); span.redStep = SignedFloatToFixed(drdx); drdy = oneOverArea * (eMaj.dx * eBot_dr - eMaj_dr * eBot.dx); eMaj_dg = (GLfloat) ((GLint) vMax->color[GCOMP] - (GLint) vMin->color[GCOMP]); eBot_dg = (GLfloat) ((GLint) vMid->color[GCOMP] - (GLint) vMin->color[GCOMP]); dgdx = oneOverArea * (eMaj_dg * eBot.dy - eMaj.dy * eBot_dg); span.greenStep = SignedFloatToFixed(dgdx); dgdy = oneOverArea * (eMaj.dx * eBot_dg - eMaj_dg * eBot.dx); eMaj_db = (GLfloat) ((GLint) vMax->color[BCOMP] - (GLint) vMin->color[BCOMP]); eBot_db = (GLfloat) ((GLint) vMid->color[BCOMP] - (GLint) vMin->color[BCOMP]); dbdx = oneOverArea * (eMaj_db * eBot.dy - eMaj.dy * eBot_db); span.blueStep = SignedFloatToFixed(dbdx); dbdy = oneOverArea * (eMaj.dx * eBot_db - eMaj_db * eBot.dx); # ifdef INTERP_ALPHA eMaj_da = (GLfloat) ((GLint) vMax->color[ACOMP] - (GLint) vMin->color[ACOMP]); eBot_da = (GLfloat) ((GLint) vMid->color[ACOMP] - (GLint) vMin->color[ACOMP]); dadx = oneOverArea * (eMaj_da * eBot.dy - eMaj.dy * eBot_da); span.alphaStep = SignedFloatToFixed(dadx); dady = oneOverArea * (eMaj.dx * eBot_da - eMaj_da * eBot.dx); # endif } else { ASSERT (ctx->Light.ShadeModel == GL_FLAT); span.interpMask |= SPAN_FLAT; drdx = drdy = 0.0F; dgdx = dgdy = 0.0F; dbdx = dbdy = 0.0F; span.redStep = 0; span.greenStep = 0; span.blueStep = 0; # ifdef INTERP_ALPHA dadx = dady = 0.0F; span.alphaStep = 0; # endif } #endif #ifdef INTERP_FLOAT_RGBA span.interpMask |= SPAN_RGBA; if (ctx->Light.ShadeModel == GL_SMOOTH) { GLfloat eMaj_dr, eBot_dr; GLfloat eMaj_dg, eBot_dg; GLfloat eMaj_db, eBot_db; GLfloat eMaj_da, eBot_da; eMaj_dr = vMax->color[RCOMP] - vMin->color[RCOMP]; eBot_dr = vMid->color[RCOMP] - vMin->color[RCOMP]; drdx = oneOverArea * (eMaj_dr * eBot.dy - eMaj.dy * eBot_dr); span.redStep = drdx; drdy = oneOverArea * (eMaj.dx * eBot_dr - eMaj_dr * eBot.dx); eMaj_dg = vMax->color[GCOMP] - vMin->color[GCOMP]; eBot_dg = vMid->color[GCOMP] - vMin->color[GCOMP]; dgdx = oneOverArea * (eMaj_dg * eBot.dy - eMaj.dy * eBot_dg); span.greenStep = dgdx; dgdy = oneOverArea * (eMaj.dx * eBot_dg - eMaj_dg * eBot.dx); eMaj_db = vMax->color[BCOMP] - vMin->color[BCOMP]; eBot_db = vMid->color[BCOMP] - vMin->color[BCOMP]; dbdx = oneOverArea * (eMaj_db * eBot.dy - eMaj.dy * eBot_db); span.blueStep = dbdx; dbdy = oneOverArea * (eMaj.dx * eBot_db - eMaj_db * eBot.dx); eMaj_da = vMax->color[ACOMP] - vMin->color[ACOMP]; eBot_da = vMid->color[ACOMP] - vMin->color[ACOMP]; dadx = oneOverArea * (eMaj_da * eBot.dy - eMaj.dy * eBot_da); span.alphaStep = dadx; dady = oneOverArea * (eMaj.dx * eBot_da - eMaj_da * eBot.dx); } else { drdx = drdy = span.redStep = 0.0F; dgdx = dgdy = span.greenStep = 0.0F; dbdx = dbdy = span.blueStep = 0.0F; dadx = dady = span.alphaStep = 0.0F; } #endif #ifdef INTERP_SPEC span.interpMask |= SPAN_SPEC; if (ctx->Light.ShadeModel == GL_SMOOTH) { GLfloat eMaj_dsr, eBot_dsr; GLfloat eMaj_dsg, eBot_dsg; GLfloat eMaj_dsb, eBot_dsb; eMaj_dsr = (GLfloat) ((GLint) vMax->specular[RCOMP] - (GLint) vMin->specular[RCOMP]); eBot_dsr = (GLfloat) ((GLint) vMid->specular[RCOMP] - (GLint) vMin->specular[RCOMP]); dsrdx = oneOverArea * (eMaj_dsr * eBot.dy - eMaj.dy * eBot_dsr); span.specRedStep = SignedFloatToFixed(dsrdx); dsrdy = oneOverArea * (eMaj.dx * eBot_dsr - eMaj_dsr * eBot.dx); eMaj_dsg = (GLfloat) ((GLint) vMax->specular[GCOMP] - (GLint) vMin->specular[GCOMP]); eBot_dsg = (GLfloat) ((GLint) vMid->specular[GCOMP] - (GLint) vMin->specular[GCOMP]); dsgdx = oneOverArea * (eMaj_dsg * eBot.dy - eMaj.dy * eBot_dsg); span.specGreenStep = SignedFloatToFixed(dsgdx); dsgdy = oneOverArea * (eMaj.dx * eBot_dsg - eMaj_dsg * eBot.dx); eMaj_dsb = (GLfloat) ((GLint) vMax->specular[BCOMP] - (GLint) vMin->specular[BCOMP]); eBot_dsb = (GLfloat) ((GLint) vMid->specular[BCOMP] - (GLint) vMin->specular[BCOMP]); dsbdx = oneOverArea * (eMaj_dsb * eBot.dy - eMaj.dy * eBot_dsb); span.specBlueStep = SignedFloatToFixed(dsbdx); dsbdy = oneOverArea * (eMaj.dx * eBot_dsb - eMaj_dsb * eBot.dx); } else { dsrdx = dsrdy = 0.0F; dsgdx = dsgdy = 0.0F; dsbdx = dsbdy = 0.0F; span.specRedStep = 0; span.specGreenStep = 0; span.specBlueStep = 0; } #endif #ifdef INTERP_FLOAT_SPEC span.interpMask |= SPAN_SPEC; if (ctx->Light.ShadeModel == GL_SMOOTH) { GLfloat eMaj_dsr, eBot_dsr; GLfloat eMaj_dsg, eBot_dsg; GLfloat eMaj_dsb, eBot_dsb; eMaj_dsr = vMax->specular[RCOMP] - vMin->specular[RCOMP]; eBot_dsr = vMid->specular[RCOMP] - vMin->specular[RCOMP]; dsrdx = oneOverArea * (eMaj_dsr * eBot.dy - eMaj.dy * eBot_dsr); span.specRedStep = dsrdx; dsrdy = oneOverArea * (eMaj.dx * eBot_dsr - eMaj_dsr * eBot.dx); eMaj_dsg = vMax->specular[GCOMP] - vMin->specular[GCOMP]; eBot_dsg = vMid->specular[GCOMP] - vMin->specular[GCOMP]; dsgdx = oneOverArea * (eMaj_dsg * eBot.dy - eMaj.dy * eBot_dsg); span.specGreenStep = dsgdx; dsgdy = oneOverArea * (eMaj.dx * eBot_dsg - eMaj_dsg * eBot.dx); eMaj_dsb = vMax->specular[BCOMP] - vMin->specular[BCOMP]; eBot_dsb = vMid->specular[BCOMP] - vMin->specular[BCOMP]; dsbdx = oneOverArea * (eMaj_dsb * eBot.dy - eMaj.dy * eBot_dsb); span.specBlueStep = dsbdx; dsbdy = oneOverArea * (eMaj.dx * eBot_dsb - eMaj_dsb * eBot.dx); } else { dsrdx = dsrdy = span.specRedStep = 0; dsgdx = dsgdy = span.specGreenStep = 0; dsbdx = dsbdy = span.specBlueStep = 0; } #endif #ifdef INTERP_INDEX span.interpMask |= SPAN_INDEX; if (ctx->Light.ShadeModel == GL_SMOOTH) { GLfloat eMaj_di, eBot_di; eMaj_di = (GLfloat) ((GLint) vMax->index - (GLint) vMin->index); eBot_di = (GLfloat) ((GLint) vMid->index - (GLint) vMin->index); didx = oneOverArea * (eMaj_di * eBot.dy - eMaj.dy * eBot_di); span.indexStep = SignedFloatToFixed(didx); didy = oneOverArea * (eMaj.dx * eBot_di - eMaj_di * eBot.dx); } else { span.interpMask |= SPAN_FLAT; didx = didy = 0.0F; span.indexStep = 0; } #endif #ifdef INTERP_INT_TEX span.interpMask |= SPAN_INT_TEXTURE; { GLfloat eMaj_ds, eBot_ds; eMaj_ds = (vMax->texcoord[0][0] - vMin->texcoord[0][0]) * S_SCALE; eBot_ds = (vMid->texcoord[0][0] - vMin->texcoord[0][0]) * S_SCALE; dsdx = oneOverArea * (eMaj_ds * eBot.dy - eMaj.dy * eBot_ds); span.intTexStep[0] = SignedFloatToFixed(dsdx); dsdy = oneOverArea * (eMaj.dx * eBot_ds - eMaj_ds * eBot.dx); } { GLfloat eMaj_dt, eBot_dt; eMaj_dt = (vMax->texcoord[0][1] - vMin->texcoord[0][1]) * T_SCALE; eBot_dt = (vMid->texcoord[0][1] - vMin->texcoord[0][1]) * T_SCALE; dtdx = oneOverArea * (eMaj_dt * eBot.dy - eMaj.dy * eBot_dt); span.intTexStep[1] = SignedFloatToFixed(dtdx); dtdy = oneOverArea * (eMaj.dx * eBot_dt - eMaj_dt * eBot.dx); } #endif #ifdef INTERP_TEX span.interpMask |= SPAN_TEXTURE; { GLfloat wMax = vMax->win[3]; GLfloat wMin = vMin->win[3]; GLfloat wMid = vMid->win[3]; GLfloat eMaj_ds, eBot_ds; GLfloat eMaj_dt, eBot_dt; GLfloat eMaj_du, eBot_du; GLfloat eMaj_dv, eBot_dv; eMaj_ds = vMax->texcoord[0][0] * wMax - vMin->texcoord[0][0] * wMin; eBot_ds = vMid->texcoord[0][0] * wMid - vMin->texcoord[0][0] * wMin; dsdx = oneOverArea * (eMaj_ds * eBot.dy - eMaj.dy * eBot_ds); dsdy = oneOverArea * (eMaj.dx * eBot_ds - eMaj_ds * eBot.dx); span.texStepX[0][0] = dsdx; span.texStepY[0][0] = dsdy; eMaj_dt = vMax->texcoord[0][1] * wMax - vMin->texcoord[0][1] * wMin; eBot_dt = vMid->texcoord[0][1] * wMid - vMin->texcoord[0][1] * wMin; dtdx = oneOverArea * (eMaj_dt * eBot.dy - eMaj.dy * eBot_dt); dtdy = oneOverArea * (eMaj.dx * eBot_dt - eMaj_dt * eBot.dx); span.texStepX[0][1] = dtdx; span.texStepY[0][1] = dtdy; eMaj_du = vMax->texcoord[0][2] * wMax - vMin->texcoord[0][2] * wMin; eBot_du = vMid->texcoord[0][2] * wMid - vMin->texcoord[0][2] * wMin; dudx = oneOverArea * (eMaj_du * eBot.dy - eMaj.dy * eBot_du); dudy = oneOverArea * (eMaj.dx * eBot_du - eMaj_du * eBot.dx); span.texStepX[0][2] = dudx; span.texStepY[0][2] = dudy; eMaj_dv = vMax->texcoord[0][3] * wMax - vMin->texcoord[0][3] * wMin; eBot_dv = vMid->texcoord[0][3] * wMid - vMin->texcoord[0][3] * wMin; dvdx = oneOverArea * (eMaj_dv * eBot.dy - eMaj.dy * eBot_dv); dvdy = oneOverArea * (eMaj.dx * eBot_dv - eMaj_dv * eBot.dx); span.texStepX[0][3] = dvdx; span.texStepY[0][3] = dvdy; } #endif #ifdef INTERP_MULTITEX span.interpMask |= SPAN_TEXTURE; { GLfloat wMax = vMax->win[3]; GLfloat wMin = vMin->win[3]; GLfloat wMid = vMid->win[3]; GLuint u; for (u = 0; u < ctx->Const.MaxTextureUnits; u++) { if (ctx->Texture.Unit[u]._ReallyEnabled) { GLfloat eMaj_ds, eBot_ds; GLfloat eMaj_dt, eBot_dt; GLfloat eMaj_du, eBot_du; GLfloat eMaj_dv, eBot_dv; eMaj_ds = vMax->texcoord[u][0] * wMax - vMin->texcoord[u][0] * wMin; eBot_ds = vMid->texcoord[u][0] * wMid - vMin->texcoord[u][0] * wMin; dsdx[u] = oneOverArea * (eMaj_ds * eBot.dy - eMaj.dy * eBot_ds); dsdy[u] = oneOverArea * (eMaj.dx * eBot_ds - eMaj_ds * eBot.dx); span.texStepX[u][0] = dsdx[u]; span.texStepY[u][0] = dsdy[u]; eMaj_dt = vMax->texcoord[u][1] * wMax - vMin->texcoord[u][1] * wMin; eBot_dt = vMid->texcoord[u][1] * wMid - vMin->texcoord[u][1] * wMin; dtdx[u] = oneOverArea * (eMaj_dt * eBot.dy - eMaj.dy * eBot_dt); dtdy[u] = oneOverArea * (eMaj.dx * eBot_dt - eMaj_dt * eBot.dx); span.texStepX[u][1] = dtdx[u]; span.texStepY[u][1] = dtdy[u]; eMaj_du = vMax->texcoord[u][2] * wMax - vMin->texcoord[u][2] * wMin; eBot_du = vMid->texcoord[u][2] * wMid - vMin->texcoord[u][2] * wMin; dudx[u] = oneOverArea * (eMaj_du * eBot.dy - eMaj.dy * eBot_du); dudy[u] = oneOverArea * (eMaj.dx * eBot_du - eMaj_du * eBot.dx); span.texStepX[u][2] = dudx[u]; span.texStepY[u][2] = dudy[u]; eMaj_dv = vMax->texcoord[u][3] * wMax - vMin->texcoord[u][3] * wMin; eBot_dv = vMid->texcoord[u][3] * wMid - vMin->texcoord[u][3] * wMin; dvdx[u] = oneOverArea * (eMaj_dv * eBot.dy - eMaj.dy * eBot_dv); dvdy[u] = oneOverArea * (eMaj.dx * eBot_dv - eMaj_dv * eBot.dx); span.texStepX[u][3] = dvdx[u]; span.texStepY[u][3] = dvdy[u]; } } } #endif /* * We always sample at pixel centers. However, we avoid * explicit half-pixel offsets in this code by incorporating * the proper offset in each of x and y during the * transformation to window coordinates. * * We also apply the usual rasterization rules to prevent * cracks and overlaps. A pixel is considered inside a * subtriangle if it meets all of four conditions: it is on or * to the right of the left edge, strictly to the left of the * right edge, on or below the top edge, and strictly above * the bottom edge. (Some edges may be degenerate.) * * The following discussion assumes left-to-right scanning * (that is, the major edge is on the left); the right-to-left * case is a straightforward variation. * * We start by finding the half-integral y coordinate that is * at or below the top of the triangle. This gives us the * first scan line that could possibly contain pixels that are * inside the triangle. * * Next we creep down the major edge until we reach that y, * and compute the corresponding x coordinate on the edge. * Then we find the half-integral x that lies on or just * inside the edge. This is the first pixel that might lie in * the interior of the triangle. (We won't know for sure * until we check the other edges.) * * As we rasterize the triangle, we'll step down the major * edge. For each step in y, we'll move an integer number * of steps in x. There are two possible x step sizes, which * we'll call the ``inner'' step (guaranteed to land on the * edge or inside it) and the ``outer'' step (guaranteed to * land on the edge or outside it). The inner and outer steps * differ by one. During rasterization we maintain an error * term that indicates our distance from the true edge, and * select either the inner step or the outer step, whichever * gets us to the first pixel that falls inside the triangle. * * All parameters (z, red, etc.) as well as the buffer * addresses for color and z have inner and outer step values, * so that we can increment them appropriately. This method * eliminates the need to adjust parameters by creeping a * sub-pixel amount into the triangle at each scanline. */ { int subTriangle; GLfixed fx; GLfixed fxLeftEdge = 0, fxRightEdge = 0; GLfixed fdxLeftEdge = 0, fdxRightEdge = 0; GLfixed fdxOuter; int idxOuter; float dxOuter; GLfixed fError = 0, fdError = 0; float adjx, adjy; GLfixed fy; #ifdef PIXEL_ADDRESS PIXEL_TYPE *pRow = NULL; int dPRowOuter = 0, dPRowInner; /* offset in bytes */ #endif #ifdef INTERP_Z # ifdef DEPTH_TYPE DEPTH_TYPE *zRow = NULL; int dZRowOuter = 0, dZRowInner; /* offset in bytes */ # endif GLfixed fz = 0, fdzOuter = 0, fdzInner; #endif #ifdef INTERP_FOG GLfloat fogLeft = 0, dfogOuter = 0, dfogInner; #endif #ifdef INTERP_RGB GLfixed fr = 0, fdrOuter = 0, fdrInner; GLfixed fg = 0, fdgOuter = 0, fdgInner; GLfixed fb = 0, fdbOuter = 0, fdbInner; #endif #ifdef INTERP_ALPHA GLfixed fa = 0, fdaOuter = 0, fdaInner; #endif #ifdef INTERP_FLOAT_RGBA GLfloat fr, fdrOuter, fdrInner; GLfloat fg, fdgOuter, fdgInner; GLfloat fb, fdbOuter, fdbInner; GLfloat fa, fdaOuter, fdaInner; #endif #ifdef INTERP_SPEC GLfixed fsr=0, fdsrOuter=0, fdsrInner; GLfixed fsg=0, fdsgOuter=0, fdsgInner; GLfixed fsb=0, fdsbOuter=0, fdsbInner; #endif #ifdef INTERP_FLOAT_SPEC GLfloat fsr=0, fdsrOuter=0, fdsrInner; GLfloat fsg=0, fdsgOuter=0, fdsgInner; GLfloat fsb=0, fdsbOuter=0, fdsbInner; #endif #ifdef INTERP_INDEX GLfixed fi=0, fdiOuter=0, fdiInner; #endif #ifdef INTERP_INT_TEX GLfixed fs=0, fdsOuter=0, fdsInner; GLfixed ft=0, fdtOuter=0, fdtInner; #endif #ifdef INTERP_TEX GLfloat sLeft=0, dsOuter=0, dsInner; GLfloat tLeft=0, dtOuter=0, dtInner; GLfloat uLeft=0, duOuter=0, duInner; GLfloat vLeft=0, dvOuter=0, dvInner; #endif #ifdef INTERP_MULTITEX GLfloat sLeft[MAX_TEXTURE_UNITS]; GLfloat tLeft[MAX_TEXTURE_UNITS]; GLfloat uLeft[MAX_TEXTURE_UNITS]; GLfloat vLeft[MAX_TEXTURE_UNITS]; GLfloat dsOuter[MAX_TEXTURE_UNITS], dsInner[MAX_TEXTURE_UNITS]; GLfloat dtOuter[MAX_TEXTURE_UNITS], dtInner[MAX_TEXTURE_UNITS]; GLfloat duOuter[MAX_TEXTURE_UNITS], duInner[MAX_TEXTURE_UNITS]; GLfloat dvOuter[MAX_TEXTURE_UNITS], dvInner[MAX_TEXTURE_UNITS]; #endif for (subTriangle=0; subTriangle<=1; subTriangle++) { EdgeT *eLeft, *eRight; int setupLeft, setupRight; int lines; if (subTriangle==0) { /* bottom half */ if (scan_from_left_to_right) { eLeft = &eMaj; eRight = &eBot; lines = eRight->lines; setupLeft = 1; setupRight = 1; } else { eLeft = &eBot; eRight = &eMaj; lines = eLeft->lines; setupLeft = 1; setupRight = 1; } } else { /* top half */ if (scan_from_left_to_right) { eLeft = &eMaj; eRight = &eTop; lines = eRight->lines; setupLeft = 0; setupRight = 1; } else { eLeft = &eTop; eRight = &eMaj; lines = eLeft->lines; setupLeft = 1; setupRight = 0; } if (lines == 0) return; } if (setupLeft && eLeft->lines > 0) { const SWvertex *vLower; GLfixed fsx = eLeft->fsx; fx = FixedCeil(fsx); fError = fx - fsx - FIXED_ONE; fxLeftEdge = fsx - FIXED_EPSILON; fdxLeftEdge = eLeft->fdxdy; fdxOuter = FixedFloor(fdxLeftEdge - FIXED_EPSILON); fdError = fdxOuter - fdxLeftEdge + FIXED_ONE; idxOuter = FixedToInt(fdxOuter); dxOuter = (float) idxOuter; (void) dxOuter; fy = eLeft->fsy; span.y = FixedToInt(fy); adjx = (float)(fx - eLeft->fx0); /* SCALED! */ adjy = eLeft->adjy; /* SCALED! */ (void) adjx; /* silence compiler warnings */ (void) adjy; /* silence compiler warnings */ vLower = eLeft->v0; (void) vLower; /* silence compiler warnings */ #ifdef PIXEL_ADDRESS { pRow = (PIXEL_TYPE *) PIXEL_ADDRESS(FixedToInt(fxLeftEdge), span.y); dPRowOuter = -((int)BYTES_PER_ROW) + idxOuter * sizeof(PIXEL_TYPE); /* negative because Y=0 at bottom and increases upward */ } #endif /* * Now we need the set of parameter (z, color, etc.) values at * the point (fx, fy). This gives us properly-sampled parameter * values that we can step from pixel to pixel. Furthermore, * although we might have intermediate results that overflow * the normal parameter range when we step temporarily outside * the triangle, we shouldn't overflow or underflow for any * pixel that's actually inside the triangle. */ #ifdef INTERP_Z { GLfloat z0 = vLower->win[2]; if (depthBits <= 16) { /* interpolate fixed-pt values */ GLfloat tmp = (z0 * FIXED_SCALE + dzdx * adjx + dzdy * adjy) + FIXED_HALF; if (tmp < MAX_GLUINT / 2) fz = (GLfixed) tmp; else fz = MAX_GLUINT / 2; fdzOuter = SignedFloatToFixed(dzdy + dxOuter * dzdx); } else { /* interpolate depth values exactly */ fz = (GLint) (z0 + dzdx * FixedToFloat(adjx) + dzdy * FixedToFloat(adjy)); fdzOuter = (GLint) (dzdy + dxOuter * dzdx); } # ifdef DEPTH_TYPE zRow = (DEPTH_TYPE *) _mesa_zbuffer_address(ctx, FixedToInt(fxLeftEdge), span.y); dZRowOuter = (ctx->DrawBuffer->Width + idxOuter) * sizeof(DEPTH_TYPE); # endif } #endif #ifdef INTERP_FOG fogLeft = vLower->fog + (span.fogStep * adjx + dfogdy * adjy) * (1.0F/FIXED_SCALE); dfogOuter = dfogdy + dxOuter * span.fogStep; #endif #ifdef INTERP_RGB if (ctx->Light.ShadeModel == GL_SMOOTH) { fr = (GLfixed) (ChanToFixed(vLower->color[RCOMP]) + drdx * adjx + drdy * adjy) + FIXED_HALF; fdrOuter = SignedFloatToFixed(drdy + dxOuter * drdx); fg = (GLfixed) (ChanToFixed(vLower->color[GCOMP]) + dgdx * adjx + dgdy * adjy) + FIXED_HALF; fdgOuter = SignedFloatToFixed(dgdy + dxOuter * dgdx); fb = (GLfixed) (ChanToFixed(vLower->color[BCOMP]) + dbdx * adjx + dbdy * adjy) + FIXED_HALF; fdbOuter = SignedFloatToFixed(dbdy + dxOuter * dbdx); # ifdef INTERP_ALPHA fa = (GLfixed) (ChanToFixed(vLower->color[ACOMP]) + dadx * adjx + dady * adjy) + FIXED_HALF; fdaOuter = SignedFloatToFixed(dady + dxOuter * dadx); # endif } else { ASSERT (ctx->Light.ShadeModel == GL_FLAT); fr = ChanToFixed(v2->color[RCOMP]); fg = ChanToFixed(v2->color[GCOMP]); fb = ChanToFixed(v2->color[BCOMP]); fdrOuter = fdgOuter = fdbOuter = 0; # ifdef INTERP_ALPHA fa = ChanToFixed(v2->color[ACOMP]); fdaOuter = 0; # endif } #endif #ifdef INTERP_FLOAT_RGBA if (ctx->Light.ShadeModel == GL_SMOOTH) { fr = vLower->color[RCOMP] + (drdx * adjx + drdy * adjy) * (1.0F / FIXED_SCALE); fdrOuter = drdy + dxOuter * drdx; fg = vLower->color[GCOMP] + (dgdx * adjx + dgdy * adjy) * (1.0F / FIXED_SCALE); fdgOuter = dgdy + dxOuter * dgdx; fb = vLower->color[BCOMP] + (dbdx * adjx + dbdy * adjy) * (1.0F / FIXED_SCALE); fdbOuter = dbdy + dxOuter * dbdx; fa = vLower->color[ACOMP] + (dadx * adjx + dady * adjy) * (1.0F / FIXED_SCALE); fdaOuter = dady + dxOuter * dadx; } else { fr = v2->color[RCOMP]; fg = v2->color[GCOMP]; fb = v2->color[BCOMP]; fa = v2->color[ACOMP]; fdrOuter = fdgOuter = fdbOuter = fdaOuter = 0.0F; } #endif #ifdef INTERP_SPEC if (ctx->Light.ShadeModel == GL_SMOOTH) { fsr = (GLfixed) (ChanToFixed(vLower->specular[RCOMP]) + dsrdx * adjx + dsrdy * adjy) + FIXED_HALF; fdsrOuter = SignedFloatToFixed(dsrdy + dxOuter * dsrdx); fsg = (GLfixed) (ChanToFixed(vLower->specular[GCOMP]) + dsgdx * adjx + dsgdy * adjy) + FIXED_HALF; fdsgOuter = SignedFloatToFixed(dsgdy + dxOuter * dsgdx); fsb = (GLfixed) (ChanToFixed(vLower->specular[BCOMP]) + dsbdx * adjx + dsbdy * adjy) + FIXED_HALF; fdsbOuter = SignedFloatToFixed(dsbdy + dxOuter * dsbdx); } else { fsr = ChanToFixed(v2->specular[RCOMP]); fsg = ChanToFixed(v2->specular[GCOMP]); fsb = ChanToFixed(v2->specular[BCOMP]); fdsrOuter = fdsgOuter = fdsbOuter = 0; } #endif #ifdef INTERP_FLOAT_SPEC if (ctx->Light.ShadeModel == GL_SMOOTH) { fsr = vLower->specular[RCOMP] + (dsrdx * adjx + dsrdy * adjy) * (1.0F / FIXED_SCALE); fdsrOuter = dsrdy + dxOuter * dsrdx; fsg = vLower->specular[GCOMP] + (dsgdx * adjx + dsgdy * adjy) * (1.0F / FIXED_SCALE); fdsgOuter = dsgdy + dxOuter * dsgdx; fsb = vLower->specular[BCOMP] + (dsbdx * adjx + dsbdy * adjy) * (1.0F / FIXED_SCALE); fdsbOuter = dsbdy + dxOuter * dsbdx; } else { fsr = v2->specular[RCOMP]; fsg = v2->specular[GCOMP]; fsb = v2->specular[BCOMP]; fdsrOuter = fdsgOuter = fdsbOuter = 0.0F; } #endif #ifdef INTERP_INDEX if (ctx->Light.ShadeModel == GL_SMOOTH) { fi = (GLfixed)(vLower->index * FIXED_SCALE + didx * adjx + didy * adjy) + FIXED_HALF; fdiOuter = SignedFloatToFixed(didy + dxOuter * didx); } else { fi = (GLfixed) (v2->index * FIXED_SCALE); fdiOuter = 0; } #endif #ifdef INTERP_INT_TEX { GLfloat s0, t0; s0 = vLower->texcoord[0][0] * S_SCALE; fs = (GLfixed)(s0 * FIXED_SCALE + dsdx * adjx + dsdy * adjy) + FIXED_HALF; fdsOuter = SignedFloatToFixed(dsdy + dxOuter * dsdx); t0 = vLower->texcoord[0][1] * T_SCALE; ft = (GLfixed)(t0 * FIXED_SCALE + dtdx * adjx + dtdy * adjy) + FIXED_HALF; fdtOuter = SignedFloatToFixed(dtdy + dxOuter * dtdx); } #endif #ifdef INTERP_TEX { GLfloat invW = vLower->win[3]; GLfloat s0, t0, u0, v0; s0 = vLower->texcoord[0][0] * invW; sLeft = s0 + (span.texStepX[0][0] * adjx + dsdy * adjy) * (1.0F/FIXED_SCALE); dsOuter = dsdy + dxOuter * span.texStepX[0][0]; t0 = vLower->texcoord[0][1] * invW; tLeft = t0 + (span.texStepX[0][1] * adjx + dtdy * adjy) * (1.0F/FIXED_SCALE); dtOuter = dtdy + dxOuter * span.texStepX[0][1]; u0 = vLower->texcoord[0][2] * invW; uLeft = u0 + (span.texStepX[0][2] * adjx + dudy * adjy) * (1.0F/FIXED_SCALE); duOuter = dudy + dxOuter * span.texStepX[0][2]; v0 = vLower->texcoord[0][3] * invW; vLeft = v0 + (span.texStepX[0][3] * adjx + dvdy * adjy) * (1.0F/FIXED_SCALE); dvOuter = dvdy + dxOuter * span.texStepX[0][3]; } #endif #ifdef INTERP_MULTITEX { GLuint u; for (u = 0; u < ctx->Const.MaxTextureUnits; u++) { if (ctx->Texture.Unit[u]._ReallyEnabled) { GLfloat invW = vLower->win[3]; GLfloat s0, t0, u0, v0; s0 = vLower->texcoord[u][0] * invW; sLeft[u] = s0 + (span.texStepX[u][0] * adjx + dsdy[u] * adjy) * (1.0F/FIXED_SCALE); dsOuter[u] = dsdy[u] + dxOuter * span.texStepX[u][0]; t0 = vLower->texcoord[u][1] * invW; tLeft[u] = t0 + (span.texStepX[u][1] * adjx + dtdy[u] * adjy) * (1.0F/FIXED_SCALE); dtOuter[u] = dtdy[u] + dxOuter * span.texStepX[u][1]; u0 = vLower->texcoord[u][2] * invW; uLeft[u] = u0 + (span.texStepX[u][2] * adjx + dudy[u] * adjy) * (1.0F/FIXED_SCALE); duOuter[u] = dudy[u] + dxOuter * span.texStepX[u][2]; v0 = vLower->texcoord[u][3] * invW; vLeft[u] = v0 + (span.texStepX[u][3] * adjx + dvdy[u] * adjy) * (1.0F/FIXED_SCALE); dvOuter[u] = dvdy[u] + dxOuter * span.texStepX[u][3]; } } } #endif } /*if setupLeft*/ if (setupRight && eRight->lines>0) { fxRightEdge = eRight->fsx - FIXED_EPSILON; fdxRightEdge = eRight->fdxdy; } if (lines==0) { continue; } /* Rasterize setup */ #ifdef PIXEL_ADDRESS dPRowInner = dPRowOuter + sizeof(PIXEL_TYPE); #endif #ifdef INTERP_Z # ifdef DEPTH_TYPE dZRowInner = dZRowOuter + sizeof(DEPTH_TYPE); # endif fdzInner = fdzOuter + span.zStep; #endif #ifdef INTERP_FOG dfogInner = dfogOuter + span.fogStep; #endif #if defined(INTERP_RGB) || defined(INTERP_FLOAT_RGBA) fdrInner = fdrOuter + span.redStep; fdgInner = fdgOuter + span.greenStep; fdbInner = fdbOuter + span.blueStep; #endif #if defined(INTERP_ALPHA) || defined(INTERP_FLOAT_RGBA) fdaInner = fdaOuter + span.alphaStep; #endif #if defined(INTERP_SPEC) || defined(INTERP_FLOAT_SPEC) fdsrInner = fdsrOuter + span.specRedStep; fdsgInner = fdsgOuter + span.specGreenStep; fdsbInner = fdsbOuter + span.specBlueStep; #endif #ifdef INTERP_INDEX fdiInner = fdiOuter + span.indexStep; #endif #ifdef INTERP_INT_TEX fdsInner = fdsOuter + span.intTexStep[0]; fdtInner = fdtOuter + span.intTexStep[1]; #endif #ifdef INTERP_TEX dsInner = dsOuter + span.texStepX[0][0]; dtInner = dtOuter + span.texStepX[0][1]; duInner = duOuter + span.texStepX[0][2]; dvInner = dvOuter + span.texStepX[0][3]; #endif #ifdef INTERP_MULTITEX { GLuint u; for (u = 0; u < ctx->Const.MaxTextureUnits; u++) { if (ctx->Texture.Unit[u]._ReallyEnabled) { dsInner[u] = dsOuter[u] + span.texStepX[u][0]; dtInner[u] = dtOuter[u] + span.texStepX[u][1]; duInner[u] = duOuter[u] + span.texStepX[u][2]; dvInner[u] = dvOuter[u] + span.texStepX[u][3]; } } } #endif while (lines > 0) { /* initialize the span interpolants to the leftmost value */ /* ff = fixed-pt fragment */ const GLint right = FixedToInt(fxRightEdge); span.x = FixedToInt(fxLeftEdge); if (right <= span.x) span.end = 0; else span.end = right - span.x; #ifdef INTERP_Z span.z = fz; #endif #ifdef INTERP_FOG span.fog = fogLeft; #endif #if defined(INTERP_RGB) || defined(INTERP_FLOAT_RGBA) span.red = fr; span.green = fg; span.blue = fb; #endif #if defined(INTERP_ALPHA) || defined(INTERP_FLOAT_RGBA) span.alpha = fa; #endif #if defined(INTERP_SPEC) || defined(INTERP_FLOAT_SPEC) span.specRed = fsr; span.specGreen = fsg; span.specBlue = fsb; #endif #ifdef INTERP_INDEX span.index = fi; #endif #ifdef INTERP_INT_TEX span.intTex[0] = fs; span.intTex[1] = ft; #endif #ifdef INTERP_TEX span.tex[0][0] = sLeft; span.tex[0][1] = tLeft; span.tex[0][2] = uLeft; span.tex[0][3] = vLeft; #endif #ifdef INTERP_MULTITEX { GLuint u; for (u = 0; u < ctx->Const.MaxTextureUnits; u++) { if (ctx->Texture.Unit[u]._ReallyEnabled) { span.tex[u][0] = sLeft[u]; span.tex[u][1] = tLeft[u]; span.tex[u][2] = uLeft[u]; span.tex[u][3] = vLeft[u]; } } } #endif #ifdef INTERP_RGB { /* need this to accomodate round-off errors */ const GLint len = right - span.x - 1; GLfixed ffrend = span.red + len * span.redStep; GLfixed ffgend = span.green + len * span.greenStep; GLfixed ffbend = span.blue + len * span.blueStep; if (ffrend < 0) { span.red -= ffrend; if (span.red < 0) span.red = 0; } if (ffgend < 0) { span.green -= ffgend; if (span.green < 0) span.green = 0; } if (ffbend < 0) { span.blue -= ffbend; if (span.blue < 0) span.blue = 0; } } #endif #ifdef INTERP_ALPHA { const GLint len = right - span.x - 1; GLfixed ffaend = span.alpha + len * span.alphaStep; if (ffaend < 0) { span.alpha -= ffaend; if (span.alpha < 0) span.alpha = 0; } } #endif #ifdef INTERP_SPEC { /* need this to accomodate round-off errors */ const GLint len = right - span.x - 1; GLfixed ffsrend = span.specRed + len * span.specRedStep; GLfixed ffsgend = span.specGreen + len * span.specGreenStep; GLfixed ffsbend = span.specBlue + len * span.specBlueStep; if (ffsrend < 0) { span.specRed -= ffsrend; if (span.specRed < 0) span.specRed = 0; } if (ffsgend < 0) { span.specGreen -= ffsgend; if (span.specGreen < 0) span.specGreen = 0; } if (ffsbend < 0) { span.specBlue -= ffsbend; if (span.specBlue < 0) span.specBlue = 0; } } #endif #ifdef INTERP_INDEX if (span.index < 0) span.index = 0; #endif /* This is where we actually generate fragments */ if (span.end > 0) { RENDER_SPAN( span ); } /* * Advance to the next scan line. Compute the * new edge coordinates, and adjust the * pixel-center x coordinate so that it stays * on or inside the major edge. */ span.y++; lines--; fxLeftEdge += fdxLeftEdge; fxRightEdge += fdxRightEdge; fError += fdError; if (fError >= 0) { fError -= FIXED_ONE; #ifdef PIXEL_ADDRESS pRow = (PIXEL_TYPE *) ((GLubyte *) pRow + dPRowOuter); #endif #ifdef INTERP_Z # ifdef DEPTH_TYPE zRow = (DEPTH_TYPE *) ((GLubyte *) zRow + dZRowOuter); # endif fz += fdzOuter; #endif #ifdef INTERP_FOG fogLeft += dfogOuter; #endif #if defined(INTERP_RGB) || defined(INTERP_FLOAT_RGBA) fr += fdrOuter; fg += fdgOuter; fb += fdbOuter; #endif #if defined(INTERP_ALPHA) || defined(INTERP_FLOAT_RGBA) fa += fdaOuter; #endif #if defined(INTERP_SPEC) || defined(INTERP_FLOAT_SPEC) fsr += fdsrOuter; fsg += fdsgOuter; fsb += fdsbOuter; #endif #ifdef INTERP_INDEX fi += fdiOuter; #endif #ifdef INTERP_INT_TEX fs += fdsOuter; ft += fdtOuter; #endif #ifdef INTERP_TEX sLeft += dsOuter; tLeft += dtOuter; uLeft += duOuter; vLeft += dvOuter; #endif #ifdef INTERP_MULTITEX { GLuint u; for (u = 0; u < ctx->Const.MaxTextureUnits; u++) { if (ctx->Texture.Unit[u]._ReallyEnabled) { sLeft[u] += dsOuter[u]; tLeft[u] += dtOuter[u]; uLeft[u] += duOuter[u]; vLeft[u] += dvOuter[u]; } } } #endif } else { #ifdef PIXEL_ADDRESS pRow = (PIXEL_TYPE *) ((GLubyte *) pRow + dPRowInner); #endif #ifdef INTERP_Z # ifdef DEPTH_TYPE zRow = (DEPTH_TYPE *) ((GLubyte *) zRow + dZRowInner); # endif fz += fdzInner; #endif #ifdef INTERP_FOG fogLeft += dfogInner; #endif #if defined(INTERP_RGB) || defined(INTERP_FLOAT_RGBA) fr += fdrInner; fg += fdgInner; fb += fdbInner; #endif #if defined(INTERP_ALPHA) || defined(INTERP_FLOAT_RGBA) fa += fdaInner; #endif #if defined(INTERP_SPEC) || defined(INTERP_FLOAT_SPEC) fsr += fdsrInner; fsg += fdsgInner; fsb += fdsbInner; #endif #ifdef INTERP_INDEX fi += fdiInner; #endif #ifdef INTERP_INT_TEX fs += fdsInner; ft += fdtInner; #endif #ifdef INTERP_TEX sLeft += dsInner; tLeft += dtInner; uLeft += duInner; vLeft += dvInner; #endif #ifdef INTERP_MULTITEX { GLuint u; for (u = 0; u < ctx->Const.MaxTextureUnits; u++) { if (ctx->Texture.Unit[u]._ReallyEnabled) { sLeft[u] += dsInner[u]; tLeft[u] += dtInner[u]; uLeft[u] += duInner[u]; vLeft[u] += dvInner[u]; } } } #endif } } /*while lines>0*/ } /* for subTriangle */ } #ifdef CLEANUP_CODE CLEANUP_CODE #endif } } #undef SETUP_CODE #undef CLEANUP_CODE #undef RENDER_SPAN #undef PIXEL_TYPE #undef BYTES_PER_ROW #undef PIXEL_ADDRESS #undef INTERP_Z #undef INTERP_FOG #undef INTERP_RGB #undef INTERP_ALPHA #undef INTERP_SPEC #undef INTERP_INDEX #undef INTERP_INT_TEX #undef INTERP_TEX #undef INTERP_MULTITEX #undef INTERP_FLOAT_RGBA #undef INTERP_FLOAT_SPEC #undef S_SCALE #undef T_SCALE #undef FixedToDepth #undef DO_OCCLUSION_TEST