Blame |
Last modification |
View Log
| RSS feed
/* $Id: s_tritemp.h,v 1.1 2003-02-28 11:49:43 pj 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 / (1 << SUB_PIXEL_BITS)) - 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, GL_POLYGON, 0, 0, 0);
#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 (IS_INF_OR_NAN(area) || area == 0.0F)
return;
oneOverArea = 1.0F / area;
}
#ifndef DO_OCCLUSION_TEST
ctx->OcclusionResult = GL_TRUE;
#endif
span.facing = ctx->_Facing; /* for 2-sided stencil test */
/* 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