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-rw-r--r--mesalib/src/mesa/swrast/s_span.c3006
1 files changed, 1503 insertions, 1503 deletions
diff --git a/mesalib/src/mesa/swrast/s_span.c b/mesalib/src/mesa/swrast/s_span.c
index 75e3c53a1..9cfecc9e3 100644
--- a/mesalib/src/mesa/swrast/s_span.c
+++ b/mesalib/src/mesa/swrast/s_span.c
@@ -1,1503 +1,1503 @@
-/*
- * Mesa 3-D graphics library
- * Version: 7.5
- *
- * Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
- * Copyright (C) 2009 VMware, Inc. 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.
- */
-
-
-/**
- * \file swrast/s_span.c
- * \brief Span processing functions used by all rasterization functions.
- * This is where all the per-fragment tests are performed
- * \author Brian Paul
- */
-
-#include "main/glheader.h"
-#include "main/colormac.h"
-#include "main/macros.h"
-#include "main/imports.h"
-#include "main/image.h"
-
-#include "s_atifragshader.h"
-#include "s_alpha.h"
-#include "s_blend.h"
-#include "s_context.h"
-#include "s_depth.h"
-#include "s_fog.h"
-#include "s_logic.h"
-#include "s_masking.h"
-#include "s_fragprog.h"
-#include "s_span.h"
-#include "s_stencil.h"
-#include "s_texcombine.h"
-
-
-/**
- * Set default fragment attributes for the span using the
- * current raster values. Used prior to glDraw/CopyPixels
- * and glBitmap.
- */
-void
-_swrast_span_default_attribs(struct gl_context *ctx, SWspan *span)
-{
- GLchan r, g, b, a;
- /* Z*/
- {
- const GLfloat depthMax = ctx->DrawBuffer->_DepthMaxF;
- if (ctx->DrawBuffer->Visual.depthBits <= 16)
- span->z = FloatToFixed(ctx->Current.RasterPos[2] * depthMax + 0.5F);
- else {
- GLfloat tmpf = ctx->Current.RasterPos[2] * depthMax;
- tmpf = MIN2(tmpf, depthMax);
- span->z = (GLint)tmpf;
- }
- span->zStep = 0;
- span->interpMask |= SPAN_Z;
- }
-
- /* W (for perspective correction) */
- span->attrStart[FRAG_ATTRIB_WPOS][3] = 1.0;
- span->attrStepX[FRAG_ATTRIB_WPOS][3] = 0.0;
- span->attrStepY[FRAG_ATTRIB_WPOS][3] = 0.0;
-
- /* primary color, or color index */
- UNCLAMPED_FLOAT_TO_CHAN(r, ctx->Current.RasterColor[0]);
- UNCLAMPED_FLOAT_TO_CHAN(g, ctx->Current.RasterColor[1]);
- UNCLAMPED_FLOAT_TO_CHAN(b, ctx->Current.RasterColor[2]);
- UNCLAMPED_FLOAT_TO_CHAN(a, ctx->Current.RasterColor[3]);
-#if CHAN_TYPE == GL_FLOAT
- span->red = r;
- span->green = g;
- span->blue = b;
- span->alpha = a;
-#else
- span->red = IntToFixed(r);
- span->green = IntToFixed(g);
- span->blue = IntToFixed(b);
- span->alpha = IntToFixed(a);
-#endif
- span->redStep = 0;
- span->greenStep = 0;
- span->blueStep = 0;
- span->alphaStep = 0;
- span->interpMask |= SPAN_RGBA;
-
- COPY_4V(span->attrStart[FRAG_ATTRIB_COL0], ctx->Current.RasterColor);
- ASSIGN_4V(span->attrStepX[FRAG_ATTRIB_COL0], 0.0, 0.0, 0.0, 0.0);
- ASSIGN_4V(span->attrStepY[FRAG_ATTRIB_COL0], 0.0, 0.0, 0.0, 0.0);
-
- /* Secondary color */
- if (ctx->Light.Enabled || ctx->Fog.ColorSumEnabled)
- {
- COPY_4V(span->attrStart[FRAG_ATTRIB_COL1], ctx->Current.RasterSecondaryColor);
- ASSIGN_4V(span->attrStepX[FRAG_ATTRIB_COL1], 0.0, 0.0, 0.0, 0.0);
- ASSIGN_4V(span->attrStepY[FRAG_ATTRIB_COL1], 0.0, 0.0, 0.0, 0.0);
- }
-
- /* fog */
- {
- const SWcontext *swrast = SWRAST_CONTEXT(ctx);
- GLfloat fogVal; /* a coord or a blend factor */
- if (swrast->_PreferPixelFog) {
- /* fog blend factors will be computed from fog coordinates per pixel */
- fogVal = ctx->Current.RasterDistance;
- }
- else {
- /* fog blend factor should be computed from fogcoord now */
- fogVal = _swrast_z_to_fogfactor(ctx, ctx->Current.RasterDistance);
- }
- span->attrStart[FRAG_ATTRIB_FOGC][0] = fogVal;
- span->attrStepX[FRAG_ATTRIB_FOGC][0] = 0.0;
- span->attrStepY[FRAG_ATTRIB_FOGC][0] = 0.0;
- }
-
- /* texcoords */
- {
- GLuint i;
- for (i = 0; i < ctx->Const.MaxTextureCoordUnits; i++) {
- const GLuint attr = FRAG_ATTRIB_TEX0 + i;
- const GLfloat *tc = ctx->Current.RasterTexCoords[i];
- if (ctx->FragmentProgram._Current || ctx->ATIFragmentShader._Enabled) {
- COPY_4V(span->attrStart[attr], tc);
- }
- else if (tc[3] > 0.0F) {
- /* use (s/q, t/q, r/q, 1) */
- span->attrStart[attr][0] = tc[0] / tc[3];
- span->attrStart[attr][1] = tc[1] / tc[3];
- span->attrStart[attr][2] = tc[2] / tc[3];
- span->attrStart[attr][3] = 1.0;
- }
- else {
- ASSIGN_4V(span->attrStart[attr], 0.0F, 0.0F, 0.0F, 1.0F);
- }
- ASSIGN_4V(span->attrStepX[attr], 0.0F, 0.0F, 0.0F, 0.0F);
- ASSIGN_4V(span->attrStepY[attr], 0.0F, 0.0F, 0.0F, 0.0F);
- }
- }
-}
-
-
-/**
- * Interpolate the active attributes (and'd with attrMask) to
- * fill in span->array->attribs[].
- * Perspective correction will be done. The point/line/triangle function
- * should have computed attrStart/Step values for FRAG_ATTRIB_WPOS[3]!
- */
-static INLINE void
-interpolate_active_attribs(struct gl_context *ctx, SWspan *span, GLbitfield attrMask)
-{
- const SWcontext *swrast = SWRAST_CONTEXT(ctx);
-
- /*
- * Don't overwrite existing array values, such as colors that may have
- * been produced by glDraw/CopyPixels.
- */
- attrMask &= ~span->arrayAttribs;
-
- ATTRIB_LOOP_BEGIN
- if (attrMask & (1 << attr)) {
- const GLfloat dwdx = span->attrStepX[FRAG_ATTRIB_WPOS][3];
- GLfloat w = span->attrStart[FRAG_ATTRIB_WPOS][3];
- const GLfloat dv0dx = span->attrStepX[attr][0];
- const GLfloat dv1dx = span->attrStepX[attr][1];
- const GLfloat dv2dx = span->attrStepX[attr][2];
- const GLfloat dv3dx = span->attrStepX[attr][3];
- GLfloat v0 = span->attrStart[attr][0] + span->leftClip * dv0dx;
- GLfloat v1 = span->attrStart[attr][1] + span->leftClip * dv1dx;
- GLfloat v2 = span->attrStart[attr][2] + span->leftClip * dv2dx;
- GLfloat v3 = span->attrStart[attr][3] + span->leftClip * dv3dx;
- GLuint k;
- for (k = 0; k < span->end; k++) {
- const GLfloat invW = 1.0f / w;
- span->array->attribs[attr][k][0] = v0 * invW;
- span->array->attribs[attr][k][1] = v1 * invW;
- span->array->attribs[attr][k][2] = v2 * invW;
- span->array->attribs[attr][k][3] = v3 * invW;
- v0 += dv0dx;
- v1 += dv1dx;
- v2 += dv2dx;
- v3 += dv3dx;
- w += dwdx;
- }
- ASSERT((span->arrayAttribs & (1 << attr)) == 0);
- span->arrayAttribs |= (1 << attr);
- }
- ATTRIB_LOOP_END
-}
-
-
-/**
- * Interpolate primary colors to fill in the span->array->rgba8 (or rgb16)
- * color array.
- */
-static INLINE void
-interpolate_int_colors(struct gl_context *ctx, SWspan *span)
-{
- const GLuint n = span->end;
- GLuint i;
-
-#if CHAN_BITS != 32
- ASSERT(!(span->arrayMask & SPAN_RGBA));
-#endif
-
- switch (span->array->ChanType) {
-#if CHAN_BITS != 32
- case GL_UNSIGNED_BYTE:
- {
- GLubyte (*rgba)[4] = span->array->rgba8;
- if (span->interpMask & SPAN_FLAT) {
- GLubyte color[4];
- color[RCOMP] = FixedToInt(span->red);
- color[GCOMP] = FixedToInt(span->green);
- color[BCOMP] = FixedToInt(span->blue);
- color[ACOMP] = FixedToInt(span->alpha);
- for (i = 0; i < n; i++) {
- COPY_4UBV(rgba[i], color);
- }
- }
- else {
- GLfixed r = span->red;
- GLfixed g = span->green;
- GLfixed b = span->blue;
- GLfixed a = span->alpha;
- GLint dr = span->redStep;
- GLint dg = span->greenStep;
- GLint db = span->blueStep;
- GLint da = span->alphaStep;
- for (i = 0; i < n; i++) {
- rgba[i][RCOMP] = FixedToChan(r);
- rgba[i][GCOMP] = FixedToChan(g);
- rgba[i][BCOMP] = FixedToChan(b);
- rgba[i][ACOMP] = FixedToChan(a);
- r += dr;
- g += dg;
- b += db;
- a += da;
- }
- }
- }
- break;
- case GL_UNSIGNED_SHORT:
- {
- GLushort (*rgba)[4] = span->array->rgba16;
- if (span->interpMask & SPAN_FLAT) {
- GLushort color[4];
- color[RCOMP] = FixedToInt(span->red);
- color[GCOMP] = FixedToInt(span->green);
- color[BCOMP] = FixedToInt(span->blue);
- color[ACOMP] = FixedToInt(span->alpha);
- for (i = 0; i < n; i++) {
- COPY_4V(rgba[i], color);
- }
- }
- else {
- GLushort (*rgba)[4] = span->array->rgba16;
- GLfixed r, g, b, a;
- GLint dr, dg, db, da;
- r = span->red;
- g = span->green;
- b = span->blue;
- a = span->alpha;
- dr = span->redStep;
- dg = span->greenStep;
- db = span->blueStep;
- da = span->alphaStep;
- for (i = 0; i < n; i++) {
- rgba[i][RCOMP] = FixedToChan(r);
- rgba[i][GCOMP] = FixedToChan(g);
- rgba[i][BCOMP] = FixedToChan(b);
- rgba[i][ACOMP] = FixedToChan(a);
- r += dr;
- g += dg;
- b += db;
- a += da;
- }
- }
- }
- break;
-#endif
- case GL_FLOAT:
- interpolate_active_attribs(ctx, span, FRAG_BIT_COL0);
- break;
- default:
- _mesa_problem(ctx, "bad datatype 0x%x in interpolate_int_colors",
- span->array->ChanType);
- }
- span->arrayMask |= SPAN_RGBA;
-}
-
-
-/**
- * Populate the FRAG_ATTRIB_COL0 array.
- */
-static INLINE void
-interpolate_float_colors(SWspan *span)
-{
- GLfloat (*col0)[4] = span->array->attribs[FRAG_ATTRIB_COL0];
- const GLuint n = span->end;
- GLuint i;
-
- assert(!(span->arrayAttribs & FRAG_BIT_COL0));
-
- if (span->arrayMask & SPAN_RGBA) {
- /* convert array of int colors */
- for (i = 0; i < n; i++) {
- col0[i][0] = UBYTE_TO_FLOAT(span->array->rgba8[i][0]);
- col0[i][1] = UBYTE_TO_FLOAT(span->array->rgba8[i][1]);
- col0[i][2] = UBYTE_TO_FLOAT(span->array->rgba8[i][2]);
- col0[i][3] = UBYTE_TO_FLOAT(span->array->rgba8[i][3]);
- }
- }
- else {
- /* interpolate red/green/blue/alpha to get float colors */
- ASSERT(span->interpMask & SPAN_RGBA);
- if (span->interpMask & SPAN_FLAT) {
- GLfloat r = FixedToFloat(span->red);
- GLfloat g = FixedToFloat(span->green);
- GLfloat b = FixedToFloat(span->blue);
- GLfloat a = FixedToFloat(span->alpha);
- for (i = 0; i < n; i++) {
- ASSIGN_4V(col0[i], r, g, b, a);
- }
- }
- else {
- GLfloat r = FixedToFloat(span->red);
- GLfloat g = FixedToFloat(span->green);
- GLfloat b = FixedToFloat(span->blue);
- GLfloat a = FixedToFloat(span->alpha);
- GLfloat dr = FixedToFloat(span->redStep);
- GLfloat dg = FixedToFloat(span->greenStep);
- GLfloat db = FixedToFloat(span->blueStep);
- GLfloat da = FixedToFloat(span->alphaStep);
- for (i = 0; i < n; i++) {
- col0[i][0] = r;
- col0[i][1] = g;
- col0[i][2] = b;
- col0[i][3] = a;
- r += dr;
- g += dg;
- b += db;
- a += da;
- }
- }
- }
-
- span->arrayAttribs |= FRAG_BIT_COL0;
- span->array->ChanType = GL_FLOAT;
-}
-
-
-
-/**
- * Fill in the span.zArray array from the span->z, zStep values.
- */
-void
-_swrast_span_interpolate_z( const struct gl_context *ctx, SWspan *span )
-{
- const GLuint n = span->end;
- GLuint i;
-
- ASSERT(!(span->arrayMask & SPAN_Z));
-
- if (ctx->DrawBuffer->Visual.depthBits <= 16) {
- GLfixed zval = span->z;
- GLuint *z = span->array->z;
- for (i = 0; i < n; i++) {
- z[i] = FixedToInt(zval);
- zval += span->zStep;
- }
- }
- else {
- /* Deep Z buffer, no fixed->int shift */
- GLuint zval = span->z;
- GLuint *z = span->array->z;
- for (i = 0; i < n; i++) {
- z[i] = zval;
- zval += span->zStep;
- }
- }
- span->interpMask &= ~SPAN_Z;
- span->arrayMask |= SPAN_Z;
-}
-
-
-/**
- * Compute mipmap LOD from partial derivatives.
- * This the ideal solution, as given in the OpenGL spec.
- */
-GLfloat
-_swrast_compute_lambda(GLfloat dsdx, GLfloat dsdy, GLfloat dtdx, GLfloat dtdy,
- GLfloat dqdx, GLfloat dqdy, GLfloat texW, GLfloat texH,
- GLfloat s, GLfloat t, GLfloat q, GLfloat invQ)
-{
- GLfloat dudx = texW * ((s + dsdx) / (q + dqdx) - s * invQ);
- GLfloat dvdx = texH * ((t + dtdx) / (q + dqdx) - t * invQ);
- GLfloat dudy = texW * ((s + dsdy) / (q + dqdy) - s * invQ);
- GLfloat dvdy = texH * ((t + dtdy) / (q + dqdy) - t * invQ);
- GLfloat x = SQRTF(dudx * dudx + dvdx * dvdx);
- GLfloat y = SQRTF(dudy * dudy + dvdy * dvdy);
- GLfloat rho = MAX2(x, y);
- GLfloat lambda = LOG2(rho);
- return lambda;
-}
-
-
-/**
- * Compute mipmap LOD from partial derivatives.
- * This is a faster approximation than above function.
- */
-#if 0
-GLfloat
-_swrast_compute_lambda(GLfloat dsdx, GLfloat dsdy, GLfloat dtdx, GLfloat dtdy,
- GLfloat dqdx, GLfloat dqdy, GLfloat texW, GLfloat texH,
- GLfloat s, GLfloat t, GLfloat q, GLfloat invQ)
-{
- GLfloat dsdx2 = (s + dsdx) / (q + dqdx) - s * invQ;
- GLfloat dtdx2 = (t + dtdx) / (q + dqdx) - t * invQ;
- GLfloat dsdy2 = (s + dsdy) / (q + dqdy) - s * invQ;
- GLfloat dtdy2 = (t + dtdy) / (q + dqdy) - t * invQ;
- GLfloat maxU, maxV, rho, lambda;
- dsdx2 = FABSF(dsdx2);
- dsdy2 = FABSF(dsdy2);
- dtdx2 = FABSF(dtdx2);
- dtdy2 = FABSF(dtdy2);
- maxU = MAX2(dsdx2, dsdy2) * texW;
- maxV = MAX2(dtdx2, dtdy2) * texH;
- rho = MAX2(maxU, maxV);
- lambda = LOG2(rho);
- return lambda;
-}
-#endif
-
-
-/**
- * Fill in the span.array->attrib[FRAG_ATTRIB_TEXn] arrays from the
- * using the attrStart/Step values.
- *
- * This function only used during fixed-function fragment processing.
- *
- * Note: in the places where we divide by Q (or mult by invQ) we're
- * really doing two things: perspective correction and texcoord
- * projection. Remember, for texcoord (s,t,r,q) we need to index
- * texels with (s/q, t/q, r/q).
- */
-static void
-interpolate_texcoords(struct gl_context *ctx, SWspan *span)
-{
- const GLuint maxUnit
- = (ctx->Texture._EnabledCoordUnits > 1) ? ctx->Const.MaxTextureUnits : 1;
- GLuint u;
-
- /* XXX CoordUnits vs. ImageUnits */
- for (u = 0; u < maxUnit; u++) {
- if (ctx->Texture._EnabledCoordUnits & (1 << u)) {
- const GLuint attr = FRAG_ATTRIB_TEX0 + u;
- const struct gl_texture_object *obj = ctx->Texture.Unit[u]._Current;
- GLfloat texW, texH;
- GLboolean needLambda;
- GLfloat (*texcoord)[4] = span->array->attribs[attr];
- GLfloat *lambda = span->array->lambda[u];
- const GLfloat dsdx = span->attrStepX[attr][0];
- const GLfloat dsdy = span->attrStepY[attr][0];
- const GLfloat dtdx = span->attrStepX[attr][1];
- const GLfloat dtdy = span->attrStepY[attr][1];
- const GLfloat drdx = span->attrStepX[attr][2];
- const GLfloat dqdx = span->attrStepX[attr][3];
- const GLfloat dqdy = span->attrStepY[attr][3];
- GLfloat s = span->attrStart[attr][0] + span->leftClip * dsdx;
- GLfloat t = span->attrStart[attr][1] + span->leftClip * dtdx;
- GLfloat r = span->attrStart[attr][2] + span->leftClip * drdx;
- GLfloat q = span->attrStart[attr][3] + span->leftClip * dqdx;
-
- if (obj) {
- const struct gl_texture_image *img = obj->Image[0][obj->BaseLevel];
- needLambda = (obj->MinFilter != obj->MagFilter)
- || ctx->FragmentProgram._Current;
- texW = img->WidthScale;
- texH = img->HeightScale;
- }
- else {
- /* using a fragment program */
- texW = 1.0;
- texH = 1.0;
- needLambda = GL_FALSE;
- }
-
- if (needLambda) {
- GLuint i;
- if (ctx->FragmentProgram._Current
- || ctx->ATIFragmentShader._Enabled) {
- /* do perspective correction but don't divide s, t, r by q */
- const GLfloat dwdx = span->attrStepX[FRAG_ATTRIB_WPOS][3];
- GLfloat w = span->attrStart[FRAG_ATTRIB_WPOS][3] + span->leftClip * dwdx;
- for (i = 0; i < span->end; i++) {
- const GLfloat invW = 1.0F / w;
- texcoord[i][0] = s * invW;
- texcoord[i][1] = t * invW;
- texcoord[i][2] = r * invW;
- texcoord[i][3] = q * invW;
- lambda[i] = _swrast_compute_lambda(dsdx, dsdy, dtdx, dtdy,
- dqdx, dqdy, texW, texH,
- s, t, q, invW);
- s += dsdx;
- t += dtdx;
- r += drdx;
- q += dqdx;
- w += dwdx;
- }
- }
- else {
- for (i = 0; i < span->end; i++) {
- const GLfloat invQ = (q == 0.0F) ? 1.0F : (1.0F / q);
- texcoord[i][0] = s * invQ;
- texcoord[i][1] = t * invQ;
- texcoord[i][2] = r * invQ;
- texcoord[i][3] = q;
- lambda[i] = _swrast_compute_lambda(dsdx, dsdy, dtdx, dtdy,
- dqdx, dqdy, texW, texH,
- s, t, q, invQ);
- s += dsdx;
- t += dtdx;
- r += drdx;
- q += dqdx;
- }
- }
- span->arrayMask |= SPAN_LAMBDA;
- }
- else {
- GLuint i;
- if (ctx->FragmentProgram._Current ||
- ctx->ATIFragmentShader._Enabled) {
- /* do perspective correction but don't divide s, t, r by q */
- const GLfloat dwdx = span->attrStepX[FRAG_ATTRIB_WPOS][3];
- GLfloat w = span->attrStart[FRAG_ATTRIB_WPOS][3] + span->leftClip * dwdx;
- for (i = 0; i < span->end; i++) {
- const GLfloat invW = 1.0F / w;
- texcoord[i][0] = s * invW;
- texcoord[i][1] = t * invW;
- texcoord[i][2] = r * invW;
- texcoord[i][3] = q * invW;
- lambda[i] = 0.0;
- s += dsdx;
- t += dtdx;
- r += drdx;
- q += dqdx;
- w += dwdx;
- }
- }
- else if (dqdx == 0.0F) {
- /* Ortho projection or polygon's parallel to window X axis */
- const GLfloat invQ = (q == 0.0F) ? 1.0F : (1.0F / q);
- for (i = 0; i < span->end; i++) {
- texcoord[i][0] = s * invQ;
- texcoord[i][1] = t * invQ;
- texcoord[i][2] = r * invQ;
- texcoord[i][3] = q;
- lambda[i] = 0.0;
- s += dsdx;
- t += dtdx;
- r += drdx;
- }
- }
- else {
- for (i = 0; i < span->end; i++) {
- const GLfloat invQ = (q == 0.0F) ? 1.0F : (1.0F / q);
- texcoord[i][0] = s * invQ;
- texcoord[i][1] = t * invQ;
- texcoord[i][2] = r * invQ;
- texcoord[i][3] = q;
- lambda[i] = 0.0;
- s += dsdx;
- t += dtdx;
- r += drdx;
- q += dqdx;
- }
- }
- } /* lambda */
- } /* if */
- } /* for */
-}
-
-
-/**
- * Fill in the arrays->attribs[FRAG_ATTRIB_WPOS] array.
- */
-static INLINE void
-interpolate_wpos(struct gl_context *ctx, SWspan *span)
-{
- GLfloat (*wpos)[4] = span->array->attribs[FRAG_ATTRIB_WPOS];
- GLuint i;
- const GLfloat zScale = 1.0F / ctx->DrawBuffer->_DepthMaxF;
- GLfloat w, dw;
-
- if (span->arrayMask & SPAN_XY) {
- for (i = 0; i < span->end; i++) {
- wpos[i][0] = (GLfloat) span->array->x[i];
- wpos[i][1] = (GLfloat) span->array->y[i];
- }
- }
- else {
- for (i = 0; i < span->end; i++) {
- wpos[i][0] = (GLfloat) span->x + i;
- wpos[i][1] = (GLfloat) span->y;
- }
- }
-
- dw = span->attrStepX[FRAG_ATTRIB_WPOS][3];
- w = span->attrStart[FRAG_ATTRIB_WPOS][3] + span->leftClip * dw;
- for (i = 0; i < span->end; i++) {
- wpos[i][2] = (GLfloat) span->array->z[i] * zScale;
- wpos[i][3] = w;
- w += dw;
- }
-}
-
-
-/**
- * Apply the current polygon stipple pattern to a span of pixels.
- */
-static INLINE void
-stipple_polygon_span(struct gl_context *ctx, SWspan *span)
-{
- GLubyte *mask = span->array->mask;
-
- ASSERT(ctx->Polygon.StippleFlag);
-
- if (span->arrayMask & SPAN_XY) {
- /* arrays of x/y pixel coords */
- GLuint i;
- for (i = 0; i < span->end; i++) {
- const GLint col = span->array->x[i] % 32;
- const GLint row = span->array->y[i] % 32;
- const GLuint stipple = ctx->PolygonStipple[row];
- if (((1 << col) & stipple) == 0) {
- mask[i] = 0;
- }
- }
- }
- else {
- /* horizontal span of pixels */
- const GLuint highBit = 1 << 31;
- const GLuint stipple = ctx->PolygonStipple[span->y % 32];
- GLuint i, m = highBit >> (GLuint) (span->x % 32);
- for (i = 0; i < span->end; i++) {
- if ((m & stipple) == 0) {
- mask[i] = 0;
- }
- m = m >> 1;
- if (m == 0) {
- m = highBit;
- }
- }
- }
- span->writeAll = GL_FALSE;
-}
-
-
-/**
- * Clip a pixel span to the current buffer/window boundaries:
- * DrawBuffer->_Xmin, _Xmax, _Ymin, _Ymax. This will accomplish
- * window clipping and scissoring.
- * Return: GL_TRUE some pixels still visible
- * GL_FALSE nothing visible
- */
-static INLINE GLuint
-clip_span( struct gl_context *ctx, SWspan *span )
-{
- const GLint xmin = ctx->DrawBuffer->_Xmin;
- const GLint xmax = ctx->DrawBuffer->_Xmax;
- const GLint ymin = ctx->DrawBuffer->_Ymin;
- const GLint ymax = ctx->DrawBuffer->_Ymax;
-
- span->leftClip = 0;
-
- if (span->arrayMask & SPAN_XY) {
- /* arrays of x/y pixel coords */
- const GLint *x = span->array->x;
- const GLint *y = span->array->y;
- const GLint n = span->end;
- GLubyte *mask = span->array->mask;
- GLint i;
- if (span->arrayMask & SPAN_MASK) {
- /* note: using & intead of && to reduce branches */
- for (i = 0; i < n; i++) {
- mask[i] &= (x[i] >= xmin) & (x[i] < xmax)
- & (y[i] >= ymin) & (y[i] < ymax);
- }
- }
- else {
- /* note: using & intead of && to reduce branches */
- for (i = 0; i < n; i++) {
- mask[i] = (x[i] >= xmin) & (x[i] < xmax)
- & (y[i] >= ymin) & (y[i] < ymax);
- }
- }
- return GL_TRUE; /* some pixels visible */
- }
- else {
- /* horizontal span of pixels */
- const GLint x = span->x;
- const GLint y = span->y;
- GLint n = span->end;
-
- /* Trivial rejection tests */
- if (y < ymin || y >= ymax || x + n <= xmin || x >= xmax) {
- span->end = 0;
- return GL_FALSE; /* all pixels clipped */
- }
-
- /* Clip to right */
- if (x + n > xmax) {
- ASSERT(x < xmax);
- n = span->end = xmax - x;
- }
-
- /* Clip to the left */
- if (x < xmin) {
- const GLint leftClip = xmin - x;
- GLuint i;
-
- ASSERT(leftClip > 0);
- ASSERT(x + n > xmin);
-
- /* Clip 'leftClip' pixels from the left side.
- * The span->leftClip field will be applied when we interpolate
- * fragment attributes.
- * For arrays of values, shift them left.
- */
- for (i = 0; i < FRAG_ATTRIB_MAX; i++) {
- if (span->interpMask & (1 << i)) {
- GLuint j;
- for (j = 0; j < 4; j++) {
- span->attrStart[i][j] += leftClip * span->attrStepX[i][j];
- }
- }
- }
-
- span->red += leftClip * span->redStep;
- span->green += leftClip * span->greenStep;
- span->blue += leftClip * span->blueStep;
- span->alpha += leftClip * span->alphaStep;
- span->index += leftClip * span->indexStep;
- span->z += leftClip * span->zStep;
- span->intTex[0] += leftClip * span->intTexStep[0];
- span->intTex[1] += leftClip * span->intTexStep[1];
-
-#define SHIFT_ARRAY(ARRAY, SHIFT, LEN) \
- memcpy(ARRAY, ARRAY + (SHIFT), (LEN) * sizeof(ARRAY[0]))
-
- for (i = 0; i < FRAG_ATTRIB_MAX; i++) {
- if (span->arrayAttribs & (1 << i)) {
- /* shift array elements left by 'leftClip' */
- SHIFT_ARRAY(span->array->attribs[i], leftClip, n - leftClip);
- }
- }
-
- SHIFT_ARRAY(span->array->mask, leftClip, n - leftClip);
- SHIFT_ARRAY(span->array->rgba8, leftClip, n - leftClip);
- SHIFT_ARRAY(span->array->rgba16, leftClip, n - leftClip);
- SHIFT_ARRAY(span->array->x, leftClip, n - leftClip);
- SHIFT_ARRAY(span->array->y, leftClip, n - leftClip);
- SHIFT_ARRAY(span->array->z, leftClip, n - leftClip);
- SHIFT_ARRAY(span->array->index, leftClip, n - leftClip);
- for (i = 0; i < MAX_TEXTURE_COORD_UNITS; i++) {
- SHIFT_ARRAY(span->array->lambda[i], leftClip, n - leftClip);
- }
- SHIFT_ARRAY(span->array->coverage, leftClip, n - leftClip);
-
-#undef SHIFT_ARRAY
-
- span->leftClip = leftClip;
- span->x = xmin;
- span->end -= leftClip;
- span->writeAll = GL_FALSE;
- }
-
- ASSERT(span->x >= xmin);
- ASSERT(span->x + span->end <= xmax);
- ASSERT(span->y >= ymin);
- ASSERT(span->y < ymax);
-
- return GL_TRUE; /* some pixels visible */
- }
-}
-
-
-/**
- * Add specular colors to primary colors.
- * Only called during fixed-function operation.
- * Result is float color array (FRAG_ATTRIB_COL0).
- */
-static INLINE void
-add_specular(struct gl_context *ctx, SWspan *span)
-{
- const SWcontext *swrast = SWRAST_CONTEXT(ctx);
- const GLubyte *mask = span->array->mask;
- GLfloat (*col0)[4] = span->array->attribs[FRAG_ATTRIB_COL0];
- GLfloat (*col1)[4] = span->array->attribs[FRAG_ATTRIB_COL1];
- GLuint i;
-
- ASSERT(!ctx->FragmentProgram._Current);
- ASSERT(span->arrayMask & SPAN_RGBA);
- ASSERT(swrast->_ActiveAttribMask & FRAG_BIT_COL1);
- (void) swrast; /* silence warning */
-
- if (span->array->ChanType == GL_FLOAT) {
- if ((span->arrayAttribs & FRAG_BIT_COL0) == 0) {
- interpolate_active_attribs(ctx, span, FRAG_BIT_COL0);
- }
- }
- else {
- /* need float colors */
- if ((span->arrayAttribs & FRAG_BIT_COL0) == 0) {
- interpolate_float_colors(span);
- }
- }
-
- if ((span->arrayAttribs & FRAG_BIT_COL1) == 0) {
- /* XXX could avoid this and interpolate COL1 in the loop below */
- interpolate_active_attribs(ctx, span, FRAG_BIT_COL1);
- }
-
- ASSERT(span->arrayAttribs & FRAG_BIT_COL0);
- ASSERT(span->arrayAttribs & FRAG_BIT_COL1);
-
- for (i = 0; i < span->end; i++) {
- if (mask[i]) {
- col0[i][0] += col1[i][0];
- col0[i][1] += col1[i][1];
- col0[i][2] += col1[i][2];
- }
- }
-
- span->array->ChanType = GL_FLOAT;
-}
-
-
-/**
- * Apply antialiasing coverage value to alpha values.
- */
-static INLINE void
-apply_aa_coverage(SWspan *span)
-{
- const GLfloat *coverage = span->array->coverage;
- GLuint i;
- if (span->array->ChanType == GL_UNSIGNED_BYTE) {
- GLubyte (*rgba)[4] = span->array->rgba8;
- for (i = 0; i < span->end; i++) {
- const GLfloat a = rgba[i][ACOMP] * coverage[i];
- rgba[i][ACOMP] = (GLubyte) CLAMP(a, 0.0, 255.0);
- ASSERT(coverage[i] >= 0.0);
- ASSERT(coverage[i] <= 1.0);
- }
- }
- else if (span->array->ChanType == GL_UNSIGNED_SHORT) {
- GLushort (*rgba)[4] = span->array->rgba16;
- for (i = 0; i < span->end; i++) {
- const GLfloat a = rgba[i][ACOMP] * coverage[i];
- rgba[i][ACOMP] = (GLushort) CLAMP(a, 0.0, 65535.0);
- }
- }
- else {
- GLfloat (*rgba)[4] = span->array->attribs[FRAG_ATTRIB_COL0];
- for (i = 0; i < span->end; i++) {
- rgba[i][ACOMP] = rgba[i][ACOMP] * coverage[i];
- /* clamp later */
- }
- }
-}
-
-
-/**
- * Clamp span's float colors to [0,1]
- */
-static INLINE void
-clamp_colors(SWspan *span)
-{
- GLfloat (*rgba)[4] = span->array->attribs[FRAG_ATTRIB_COL0];
- GLuint i;
- ASSERT(span->array->ChanType == GL_FLOAT);
- for (i = 0; i < span->end; i++) {
- rgba[i][RCOMP] = CLAMP(rgba[i][RCOMP], 0.0F, 1.0F);
- rgba[i][GCOMP] = CLAMP(rgba[i][GCOMP], 0.0F, 1.0F);
- rgba[i][BCOMP] = CLAMP(rgba[i][BCOMP], 0.0F, 1.0F);
- rgba[i][ACOMP] = CLAMP(rgba[i][ACOMP], 0.0F, 1.0F);
- }
-}
-
-
-/**
- * Convert the span's color arrays to the given type.
- * The only way 'output' can be greater than zero is when we have a fragment
- * program that writes to gl_FragData[1] or higher.
- * \param output which fragment program color output is being processed
- */
-static INLINE void
-convert_color_type(SWspan *span, GLenum newType, GLuint output)
-{
- GLvoid *src, *dst;
-
- if (output > 0 || span->array->ChanType == GL_FLOAT) {
- src = span->array->attribs[FRAG_ATTRIB_COL0 + output];
- span->array->ChanType = GL_FLOAT;
- }
- else if (span->array->ChanType == GL_UNSIGNED_BYTE) {
- src = span->array->rgba8;
- }
- else {
- ASSERT(span->array->ChanType == GL_UNSIGNED_SHORT);
- src = span->array->rgba16;
- }
-
- if (newType == GL_UNSIGNED_BYTE) {
- dst = span->array->rgba8;
- }
- else if (newType == GL_UNSIGNED_SHORT) {
- dst = span->array->rgba16;
- }
- else {
- dst = span->array->attribs[FRAG_ATTRIB_COL0];
- }
-
- _mesa_convert_colors(span->array->ChanType, src,
- newType, dst,
- span->end, span->array->mask);
-
- span->array->ChanType = newType;
- span->array->rgba = dst;
-}
-
-
-
-/**
- * Apply fragment shader, fragment program or normal texturing to span.
- */
-static INLINE void
-shade_texture_span(struct gl_context *ctx, SWspan *span)
-{
- GLbitfield inputsRead;
-
- /* Determine which fragment attributes are actually needed */
- if (ctx->FragmentProgram._Current) {
- inputsRead = ctx->FragmentProgram._Current->Base.InputsRead;
- }
- else {
- /* XXX we could be a bit smarter about this */
- inputsRead = ~0;
- }
-
- if (ctx->FragmentProgram._Current ||
- ctx->ATIFragmentShader._Enabled) {
- /* programmable shading */
- if (span->primitive == GL_BITMAP && span->array->ChanType != GL_FLOAT) {
- convert_color_type(span, GL_FLOAT, 0);
- }
- else {
- span->array->rgba = (void *) span->array->attribs[FRAG_ATTRIB_COL0];
- }
-
- if (span->primitive != GL_POINT ||
- (span->interpMask & SPAN_RGBA) ||
- ctx->Point.PointSprite) {
- /* for single-pixel points, we populated the arrays already */
- interpolate_active_attribs(ctx, span, ~0);
- }
- span->array->ChanType = GL_FLOAT;
-
- if (!(span->arrayMask & SPAN_Z))
- _swrast_span_interpolate_z (ctx, span);
-
-#if 0
- if (inputsRead & FRAG_BIT_WPOS)
-#else
- /* XXX always interpolate wpos so that DDX/DDY work */
-#endif
- interpolate_wpos(ctx, span);
-
- /* Run fragment program/shader now */
- if (ctx->FragmentProgram._Current) {
- _swrast_exec_fragment_program(ctx, span);
- }
- else {
- ASSERT(ctx->ATIFragmentShader._Enabled);
- _swrast_exec_fragment_shader(ctx, span);
- }
- }
- else if (ctx->Texture._EnabledCoordUnits) {
- /* conventional texturing */
-
-#if CHAN_BITS == 32
- if ((span->arrayAttribs & FRAG_BIT_COL0) == 0) {
- interpolate_int_colors(ctx, span);
- }
-#else
- if (!(span->arrayMask & SPAN_RGBA))
- interpolate_int_colors(ctx, span);
-#endif
- if ((span->arrayAttribs & FRAG_BITS_TEX_ANY) == 0x0)
- interpolate_texcoords(ctx, span);
-
- _swrast_texture_span(ctx, span);
- }
-}
-
-
-
-/**
- * Apply all the per-fragment operations to a span.
- * This now includes texturing (_swrast_write_texture_span() is history).
- * This function may modify any of the array values in the span.
- * span->interpMask and span->arrayMask may be changed but will be restored
- * to their original values before returning.
- */
-void
-_swrast_write_rgba_span( struct gl_context *ctx, SWspan *span)
-{
- const SWcontext *swrast = SWRAST_CONTEXT(ctx);
- const GLuint *colorMask = (GLuint *) ctx->Color.ColorMask;
- const GLbitfield origInterpMask = span->interpMask;
- const GLbitfield origArrayMask = span->arrayMask;
- const GLbitfield origArrayAttribs = span->arrayAttribs;
- const GLenum origChanType = span->array->ChanType;
- void * const origRgba = span->array->rgba;
- const GLboolean shader = (ctx->FragmentProgram._Current
- || ctx->ATIFragmentShader._Enabled);
- const GLboolean shaderOrTexture = shader || ctx->Texture._EnabledCoordUnits;
- struct gl_framebuffer *fb = ctx->DrawBuffer;
-
- /*
- printf("%s() interp 0x%x array 0x%x\n", __FUNCTION__,
- span->interpMask, span->arrayMask);
- */
-
- ASSERT(span->primitive == GL_POINT ||
- span->primitive == GL_LINE ||
- span->primitive == GL_POLYGON ||
- span->primitive == GL_BITMAP);
-
- /* Fragment write masks */
- if (span->arrayMask & SPAN_MASK) {
- /* mask was initialized by caller, probably glBitmap */
- span->writeAll = GL_FALSE;
- }
- else {
- memset(span->array->mask, 1, span->end);
- span->writeAll = GL_TRUE;
- }
-
- /* Clip to window/scissor box */
- if (!clip_span(ctx, span)) {
- return;
- }
-
- ASSERT(span->end <= MAX_WIDTH);
-
- /* Depth bounds test */
- if (ctx->Depth.BoundsTest && fb->Visual.depthBits > 0) {
- if (!_swrast_depth_bounds_test(ctx, span)) {
- return;
- }
- }
-
-#ifdef DEBUG
- /* Make sure all fragments are within window bounds */
- if (span->arrayMask & SPAN_XY) {
- /* array of pixel locations */
- GLuint i;
- for (i = 0; i < span->end; i++) {
- if (span->array->mask[i]) {
- assert(span->array->x[i] >= fb->_Xmin);
- assert(span->array->x[i] < fb->_Xmax);
- assert(span->array->y[i] >= fb->_Ymin);
- assert(span->array->y[i] < fb->_Ymax);
- }
- }
- }
-#endif
-
- /* Polygon Stippling */
- if (ctx->Polygon.StippleFlag && span->primitive == GL_POLYGON) {
- stipple_polygon_span(ctx, span);
- }
-
- /* This is the normal place to compute the fragment color/Z
- * from texturing or shading.
- */
- if (shaderOrTexture && !swrast->_DeferredTexture) {
- shade_texture_span(ctx, span);
- }
-
- /* Do the alpha test */
- if (ctx->Color.AlphaEnabled) {
- if (!_swrast_alpha_test(ctx, span)) {
- /* all fragments failed test */
- goto end;
- }
- }
-
- /* Stencil and Z testing */
- if (ctx->Stencil._Enabled || ctx->Depth.Test) {
- if (!(span->arrayMask & SPAN_Z))
- _swrast_span_interpolate_z(ctx, span);
-
- if (ctx->Transform.DepthClamp)
- _swrast_depth_clamp_span(ctx, span);
-
- if (ctx->Stencil._Enabled) {
- /* Combined Z/stencil tests */
- if (!_swrast_stencil_and_ztest_span(ctx, span)) {
- /* all fragments failed test */
- goto end;
- }
- }
- else if (fb->Visual.depthBits > 0) {
- /* Just regular depth testing */
- ASSERT(ctx->Depth.Test);
- ASSERT(span->arrayMask & SPAN_Z);
- if (!_swrast_depth_test_span(ctx, span)) {
- /* all fragments failed test */
- goto end;
- }
- }
- }
-
- if (ctx->Query.CurrentOcclusionObject) {
- /* update count of 'passed' fragments */
- struct gl_query_object *q = ctx->Query.CurrentOcclusionObject;
- GLuint i;
- for (i = 0; i < span->end; i++)
- q->Result += span->array->mask[i];
- }
-
- /* We had to wait until now to check for glColorMask(0,0,0,0) because of
- * the occlusion test.
- */
- if (fb->_NumColorDrawBuffers == 1 && colorMask[0] == 0x0) {
- /* no colors to write */
- goto end;
- }
-
- /* If we were able to defer fragment color computation to now, there's
- * a good chance that many fragments will have already been killed by
- * Z/stencil testing.
- */
- if (shaderOrTexture && swrast->_DeferredTexture) {
- shade_texture_span(ctx, span);
- }
-
-#if CHAN_BITS == 32
- if ((span->arrayAttribs & FRAG_BIT_COL0) == 0) {
- interpolate_active_attribs(ctx, span, FRAG_BIT_COL0);
- }
-#else
- if ((span->arrayMask & SPAN_RGBA) == 0) {
- interpolate_int_colors(ctx, span);
- }
-#endif
-
- ASSERT(span->arrayMask & SPAN_RGBA);
-
- if (span->primitive == GL_BITMAP || !swrast->SpecularVertexAdd) {
- /* Add primary and specular (diffuse + specular) colors */
- if (!shader) {
- if (ctx->Fog.ColorSumEnabled ||
- (ctx->Light.Enabled &&
- ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)) {
- add_specular(ctx, span);
- }
- }
- }
-
- /* Fog */
- if (swrast->_FogEnabled) {
- _swrast_fog_rgba_span(ctx, span);
- }
-
- /* Antialias coverage application */
- if (span->arrayMask & SPAN_COVERAGE) {
- apply_aa_coverage(span);
- }
-
- /* Clamp color/alpha values over the range [0.0, 1.0] before storage */
- if (ctx->Color.ClampFragmentColor == GL_TRUE &&
- span->array->ChanType == GL_FLOAT) {
- clamp_colors(span);
- }
-
- /*
- * Write to renderbuffers.
- * Depending on glDrawBuffer() state and the which color outputs are
- * written by the fragment shader, we may either replicate one color to
- * all renderbuffers or write a different color to each renderbuffer.
- * multiFragOutputs=TRUE for the later case.
- */
- {
- const GLuint numBuffers = fb->_NumColorDrawBuffers;
- const struct gl_fragment_program *fp = ctx->FragmentProgram._Current;
- const GLboolean multiFragOutputs =
- (fp && fp->Base.OutputsWritten >= (1 << FRAG_RESULT_DATA0));
- GLuint buf;
-
- for (buf = 0; buf < numBuffers; buf++) {
- struct gl_renderbuffer *rb = fb->_ColorDrawBuffers[buf];
-
- /* color[fragOutput] will be written to buffer[buf] */
-
- if (rb) {
- GLchan rgbaSave[MAX_WIDTH][4];
- const GLuint fragOutput = multiFragOutputs ? buf : 0;
-
- /* set span->array->rgba to colors for render buffer's datatype */
- if (rb->DataType != span->array->ChanType || fragOutput > 0) {
- convert_color_type(span, rb->DataType, fragOutput);
- }
- else {
- if (rb->DataType == GL_UNSIGNED_BYTE) {
- span->array->rgba = span->array->rgba8;
- }
- else if (rb->DataType == GL_UNSIGNED_SHORT) {
- span->array->rgba = (void *) span->array->rgba16;
- }
- else {
- span->array->rgba = (void *)
- span->array->attribs[FRAG_ATTRIB_COL0];
- }
- }
-
- if (!multiFragOutputs && numBuffers > 1) {
- /* save colors for second, third renderbuffer writes */
- memcpy(rgbaSave, span->array->rgba,
- 4 * span->end * sizeof(GLchan));
- }
-
- ASSERT(rb->_BaseFormat == GL_RGBA || rb->_BaseFormat == GL_RGB ||
- rb->_BaseFormat == GL_ALPHA);
-
- if (ctx->Color._LogicOpEnabled) {
- _swrast_logicop_rgba_span(ctx, rb, span);
- }
- else if ((ctx->Color.BlendEnabled >> buf) & 1) {
- _swrast_blend_span(ctx, rb, span);
- }
-
- if (colorMask[buf] != 0xffffffff) {
- _swrast_mask_rgba_span(ctx, rb, span, buf);
- }
-
- if (span->arrayMask & SPAN_XY) {
- /* array of pixel coords */
- ASSERT(rb->PutValues);
- rb->PutValues(ctx, rb, span->end,
- span->array->x, span->array->y,
- span->array->rgba, span->array->mask);
- }
- else {
- /* horizontal run of pixels */
- ASSERT(rb->PutRow);
- rb->PutRow(ctx, rb, span->end, span->x, span->y,
- span->array->rgba,
- span->writeAll ? NULL: span->array->mask);
- }
-
- if (!multiFragOutputs && numBuffers > 1) {
- /* restore original span values */
- memcpy(span->array->rgba, rgbaSave,
- 4 * span->end * sizeof(GLchan));
- }
-
- } /* if rb */
- } /* for buf */
- }
-
-end:
- /* restore these values before returning */
- span->interpMask = origInterpMask;
- span->arrayMask = origArrayMask;
- span->arrayAttribs = origArrayAttribs;
- span->array->ChanType = origChanType;
- span->array->rgba = origRgba;
-}
-
-
-/**
- * Read RGBA pixels from a renderbuffer. Clipping will be done to prevent
- * reading ouside the buffer's boundaries.
- * \param dstType datatype for returned colors
- * \param rgba the returned colors
- */
-void
-_swrast_read_rgba_span( struct gl_context *ctx, struct gl_renderbuffer *rb,
- GLuint n, GLint x, GLint y, GLenum dstType,
- GLvoid *rgba)
-{
- const GLint bufWidth = (GLint) rb->Width;
- const GLint bufHeight = (GLint) rb->Height;
-
- if (y < 0 || y >= bufHeight || x + (GLint) n < 0 || x >= bufWidth) {
- /* completely above, below, or right */
- /* XXX maybe leave rgba values undefined? */
- memset(rgba, 0, 4 * n * sizeof(GLchan));
- }
- else {
- GLint skip, length;
- if (x < 0) {
- /* left edge clipping */
- skip = -x;
- length = (GLint) n - skip;
- if (length < 0) {
- /* completely left of window */
- return;
- }
- if (length > bufWidth) {
- length = bufWidth;
- }
- }
- else if ((GLint) (x + n) > bufWidth) {
- /* right edge clipping */
- skip = 0;
- length = bufWidth - x;
- if (length < 0) {
- /* completely to right of window */
- return;
- }
- }
- else {
- /* no clipping */
- skip = 0;
- length = (GLint) n;
- }
-
- ASSERT(rb);
- ASSERT(rb->GetRow);
- ASSERT(rb->_BaseFormat == GL_RGB || rb->_BaseFormat == GL_RGBA ||
- rb->_BaseFormat == GL_ALPHA);
-
- if (rb->DataType == dstType) {
- rb->GetRow(ctx, rb, length, x + skip, y,
- (GLubyte *) rgba + skip * RGBA_PIXEL_SIZE(rb->DataType));
- }
- else {
- GLuint temp[MAX_WIDTH * 4];
- rb->GetRow(ctx, rb, length, x + skip, y, temp);
- _mesa_convert_colors(rb->DataType, temp,
- dstType, (GLubyte *) rgba + skip * RGBA_PIXEL_SIZE(dstType),
- length, NULL);
- }
- }
-}
-
-
-/**
- * Wrapper for gl_renderbuffer::GetValues() which does clipping to avoid
- * reading values outside the buffer bounds.
- * We can use this for reading any format/type of renderbuffer.
- * \param valueSize is the size in bytes of each value (pixel) put into the
- * values array.
- */
-void
-_swrast_get_values(struct gl_context *ctx, struct gl_renderbuffer *rb,
- GLuint count, const GLint x[], const GLint y[],
- void *values, GLuint valueSize)
-{
- GLuint i, inCount = 0, inStart = 0;
-
- for (i = 0; i < count; i++) {
- if (x[i] >= 0 && y[i] >= 0 &&
- x[i] < (GLint) rb->Width && y[i] < (GLint) rb->Height) {
- /* inside */
- if (inCount == 0)
- inStart = i;
- inCount++;
- }
- else {
- if (inCount > 0) {
- /* read [inStart, inStart + inCount) */
- rb->GetValues(ctx, rb, inCount, x + inStart, y + inStart,
- (GLubyte *) values + inStart * valueSize);
- inCount = 0;
- }
- }
- }
- if (inCount > 0) {
- /* read last values */
- rb->GetValues(ctx, rb, inCount, x + inStart, y + inStart,
- (GLubyte *) values + inStart * valueSize);
- }
-}
-
-
-/**
- * Wrapper for gl_renderbuffer::PutRow() which does clipping.
- * \param valueSize size of each value (pixel) in bytes
- */
-void
-_swrast_put_row(struct gl_context *ctx, struct gl_renderbuffer *rb,
- GLuint count, GLint x, GLint y,
- const GLvoid *values, GLuint valueSize)
-{
- GLint skip = 0;
-
- if (y < 0 || y >= (GLint) rb->Height)
- return; /* above or below */
-
- if (x + (GLint) count <= 0 || x >= (GLint) rb->Width)
- return; /* entirely left or right */
-
- if ((GLint) (x + count) > (GLint) rb->Width) {
- /* right clip */
- GLint clip = x + count - rb->Width;
- count -= clip;
- }
-
- if (x < 0) {
- /* left clip */
- skip = -x;
- x = 0;
- count -= skip;
- }
-
- rb->PutRow(ctx, rb, count, x, y,
- (const GLubyte *) values + skip * valueSize, NULL);
-}
-
-
-/**
- * Wrapper for gl_renderbuffer::GetRow() which does clipping.
- * \param valueSize size of each value (pixel) in bytes
- */
-void
-_swrast_get_row(struct gl_context *ctx, struct gl_renderbuffer *rb,
- GLuint count, GLint x, GLint y,
- GLvoid *values, GLuint valueSize)
-{
- GLint skip = 0;
-
- if (y < 0 || y >= (GLint) rb->Height)
- return; /* above or below */
-
- if (x + (GLint) count <= 0 || x >= (GLint) rb->Width)
- return; /* entirely left or right */
-
- if (x + count > rb->Width) {
- /* right clip */
- GLint clip = x + count - rb->Width;
- count -= clip;
- }
-
- if (x < 0) {
- /* left clip */
- skip = -x;
- x = 0;
- count -= skip;
- }
-
- rb->GetRow(ctx, rb, count, x, y, (GLubyte *) values + skip * valueSize);
-}
-
-
-/**
- * Get RGBA pixels from the given renderbuffer.
- * Used by blending, logicop and masking functions.
- * \return pointer to the colors we read.
- */
-void *
-_swrast_get_dest_rgba(struct gl_context *ctx, struct gl_renderbuffer *rb,
- SWspan *span)
-{
- const GLuint pixelSize = RGBA_PIXEL_SIZE(span->array->ChanType);
- void *rbPixels;
-
- /* Point rbPixels to a temporary space */
- rbPixels = span->array->attribs[FRAG_ATTRIB_MAX - 1];
-
- /* Get destination values from renderbuffer */
- if (span->arrayMask & SPAN_XY) {
- _swrast_get_values(ctx, rb, span->end, span->array->x, span->array->y,
- rbPixels, pixelSize);
- }
- else {
- _swrast_get_row(ctx, rb, span->end, span->x, span->y,
- rbPixels, pixelSize);
- }
-
- return rbPixels;
-}
+/*
+ * Mesa 3-D graphics library
+ * Version: 7.5
+ *
+ * Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
+ * Copyright (C) 2009 VMware, Inc. 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.
+ */
+
+
+/**
+ * \file swrast/s_span.c
+ * \brief Span processing functions used by all rasterization functions.
+ * This is where all the per-fragment tests are performed
+ * \author Brian Paul
+ */
+
+#include "main/glheader.h"
+#include "main/colormac.h"
+#include "main/macros.h"
+#include "main/imports.h"
+#include "main/image.h"
+
+#include "s_atifragshader.h"
+#include "s_alpha.h"
+#include "s_blend.h"
+#include "s_context.h"
+#include "s_depth.h"
+#include "s_fog.h"
+#include "s_logic.h"
+#include "s_masking.h"
+#include "s_fragprog.h"
+#include "s_span.h"
+#include "s_stencil.h"
+#include "s_texcombine.h"
+
+
+/**
+ * Set default fragment attributes for the span using the
+ * current raster values. Used prior to glDraw/CopyPixels
+ * and glBitmap.
+ */
+void
+_swrast_span_default_attribs(struct gl_context *ctx, SWspan *span)
+{
+ GLchan r, g, b, a;
+ /* Z*/
+ {
+ const GLfloat depthMax = ctx->DrawBuffer->_DepthMaxF;
+ if (ctx->DrawBuffer->Visual.depthBits <= 16)
+ span->z = FloatToFixed(ctx->Current.RasterPos[2] * depthMax + 0.5F);
+ else {
+ GLfloat tmpf = ctx->Current.RasterPos[2] * depthMax;
+ tmpf = MIN2(tmpf, depthMax);
+ span->z = (GLint)tmpf;
+ }
+ span->zStep = 0;
+ span->interpMask |= SPAN_Z;
+ }
+
+ /* W (for perspective correction) */
+ span->attrStart[FRAG_ATTRIB_WPOS][3] = 1.0;
+ span->attrStepX[FRAG_ATTRIB_WPOS][3] = 0.0;
+ span->attrStepY[FRAG_ATTRIB_WPOS][3] = 0.0;
+
+ /* primary color, or color index */
+ UNCLAMPED_FLOAT_TO_CHAN(r, ctx->Current.RasterColor[0]);
+ UNCLAMPED_FLOAT_TO_CHAN(g, ctx->Current.RasterColor[1]);
+ UNCLAMPED_FLOAT_TO_CHAN(b, ctx->Current.RasterColor[2]);
+ UNCLAMPED_FLOAT_TO_CHAN(a, ctx->Current.RasterColor[3]);
+#if CHAN_TYPE == GL_FLOAT
+ span->red = r;
+ span->green = g;
+ span->blue = b;
+ span->alpha = a;
+#else
+ span->red = IntToFixed(r);
+ span->green = IntToFixed(g);
+ span->blue = IntToFixed(b);
+ span->alpha = IntToFixed(a);
+#endif
+ span->redStep = 0;
+ span->greenStep = 0;
+ span->blueStep = 0;
+ span->alphaStep = 0;
+ span->interpMask |= SPAN_RGBA;
+
+ COPY_4V(span->attrStart[FRAG_ATTRIB_COL0], ctx->Current.RasterColor);
+ ASSIGN_4V(span->attrStepX[FRAG_ATTRIB_COL0], 0.0, 0.0, 0.0, 0.0);
+ ASSIGN_4V(span->attrStepY[FRAG_ATTRIB_COL0], 0.0, 0.0, 0.0, 0.0);
+
+ /* Secondary color */
+ if (ctx->Light.Enabled || ctx->Fog.ColorSumEnabled)
+ {
+ COPY_4V(span->attrStart[FRAG_ATTRIB_COL1], ctx->Current.RasterSecondaryColor);
+ ASSIGN_4V(span->attrStepX[FRAG_ATTRIB_COL1], 0.0, 0.0, 0.0, 0.0);
+ ASSIGN_4V(span->attrStepY[FRAG_ATTRIB_COL1], 0.0, 0.0, 0.0, 0.0);
+ }
+
+ /* fog */
+ {
+ const SWcontext *swrast = SWRAST_CONTEXT(ctx);
+ GLfloat fogVal; /* a coord or a blend factor */
+ if (swrast->_PreferPixelFog) {
+ /* fog blend factors will be computed from fog coordinates per pixel */
+ fogVal = ctx->Current.RasterDistance;
+ }
+ else {
+ /* fog blend factor should be computed from fogcoord now */
+ fogVal = _swrast_z_to_fogfactor(ctx, ctx->Current.RasterDistance);
+ }
+ span->attrStart[FRAG_ATTRIB_FOGC][0] = fogVal;
+ span->attrStepX[FRAG_ATTRIB_FOGC][0] = 0.0;
+ span->attrStepY[FRAG_ATTRIB_FOGC][0] = 0.0;
+ }
+
+ /* texcoords */
+ {
+ GLuint i;
+ for (i = 0; i < ctx->Const.MaxTextureCoordUnits; i++) {
+ const GLuint attr = FRAG_ATTRIB_TEX0 + i;
+ const GLfloat *tc = ctx->Current.RasterTexCoords[i];
+ if (ctx->FragmentProgram._Current || ctx->ATIFragmentShader._Enabled) {
+ COPY_4V(span->attrStart[attr], tc);
+ }
+ else if (tc[3] > 0.0F) {
+ /* use (s/q, t/q, r/q, 1) */
+ span->attrStart[attr][0] = tc[0] / tc[3];
+ span->attrStart[attr][1] = tc[1] / tc[3];
+ span->attrStart[attr][2] = tc[2] / tc[3];
+ span->attrStart[attr][3] = 1.0;
+ }
+ else {
+ ASSIGN_4V(span->attrStart[attr], 0.0F, 0.0F, 0.0F, 1.0F);
+ }
+ ASSIGN_4V(span->attrStepX[attr], 0.0F, 0.0F, 0.0F, 0.0F);
+ ASSIGN_4V(span->attrStepY[attr], 0.0F, 0.0F, 0.0F, 0.0F);
+ }
+ }
+}
+
+
+/**
+ * Interpolate the active attributes (and'd with attrMask) to
+ * fill in span->array->attribs[].
+ * Perspective correction will be done. The point/line/triangle function
+ * should have computed attrStart/Step values for FRAG_ATTRIB_WPOS[3]!
+ */
+static INLINE void
+interpolate_active_attribs(struct gl_context *ctx, SWspan *span, GLbitfield attrMask)
+{
+ const SWcontext *swrast = SWRAST_CONTEXT(ctx);
+
+ /*
+ * Don't overwrite existing array values, such as colors that may have
+ * been produced by glDraw/CopyPixels.
+ */
+ attrMask &= ~span->arrayAttribs;
+
+ ATTRIB_LOOP_BEGIN
+ if (attrMask & (1 << attr)) {
+ const GLfloat dwdx = span->attrStepX[FRAG_ATTRIB_WPOS][3];
+ GLfloat w = span->attrStart[FRAG_ATTRIB_WPOS][3];
+ const GLfloat dv0dx = span->attrStepX[attr][0];
+ const GLfloat dv1dx = span->attrStepX[attr][1];
+ const GLfloat dv2dx = span->attrStepX[attr][2];
+ const GLfloat dv3dx = span->attrStepX[attr][3];
+ GLfloat v0 = span->attrStart[attr][0] + span->leftClip * dv0dx;
+ GLfloat v1 = span->attrStart[attr][1] + span->leftClip * dv1dx;
+ GLfloat v2 = span->attrStart[attr][2] + span->leftClip * dv2dx;
+ GLfloat v3 = span->attrStart[attr][3] + span->leftClip * dv3dx;
+ GLuint k;
+ for (k = 0; k < span->end; k++) {
+ const GLfloat invW = 1.0f / w;
+ span->array->attribs[attr][k][0] = v0 * invW;
+ span->array->attribs[attr][k][1] = v1 * invW;
+ span->array->attribs[attr][k][2] = v2 * invW;
+ span->array->attribs[attr][k][3] = v3 * invW;
+ v0 += dv0dx;
+ v1 += dv1dx;
+ v2 += dv2dx;
+ v3 += dv3dx;
+ w += dwdx;
+ }
+ ASSERT((span->arrayAttribs & (1 << attr)) == 0);
+ span->arrayAttribs |= (1 << attr);
+ }
+ ATTRIB_LOOP_END
+}
+
+
+/**
+ * Interpolate primary colors to fill in the span->array->rgba8 (or rgb16)
+ * color array.
+ */
+static INLINE void
+interpolate_int_colors(struct gl_context *ctx, SWspan *span)
+{
+ const GLuint n = span->end;
+ GLuint i;
+
+#if CHAN_BITS != 32
+ ASSERT(!(span->arrayMask & SPAN_RGBA));
+#endif
+
+ switch (span->array->ChanType) {
+#if CHAN_BITS != 32
+ case GL_UNSIGNED_BYTE:
+ {
+ GLubyte (*rgba)[4] = span->array->rgba8;
+ if (span->interpMask & SPAN_FLAT) {
+ GLubyte color[4];
+ color[RCOMP] = FixedToInt(span->red);
+ color[GCOMP] = FixedToInt(span->green);
+ color[BCOMP] = FixedToInt(span->blue);
+ color[ACOMP] = FixedToInt(span->alpha);
+ for (i = 0; i < n; i++) {
+ COPY_4UBV(rgba[i], color);
+ }
+ }
+ else {
+ GLfixed r = span->red;
+ GLfixed g = span->green;
+ GLfixed b = span->blue;
+ GLfixed a = span->alpha;
+ GLint dr = span->redStep;
+ GLint dg = span->greenStep;
+ GLint db = span->blueStep;
+ GLint da = span->alphaStep;
+ for (i = 0; i < n; i++) {
+ rgba[i][RCOMP] = FixedToChan(r);
+ rgba[i][GCOMP] = FixedToChan(g);
+ rgba[i][BCOMP] = FixedToChan(b);
+ rgba[i][ACOMP] = FixedToChan(a);
+ r += dr;
+ g += dg;
+ b += db;
+ a += da;
+ }
+ }
+ }
+ break;
+ case GL_UNSIGNED_SHORT:
+ {
+ GLushort (*rgba)[4] = span->array->rgba16;
+ if (span->interpMask & SPAN_FLAT) {
+ GLushort color[4];
+ color[RCOMP] = FixedToInt(span->red);
+ color[GCOMP] = FixedToInt(span->green);
+ color[BCOMP] = FixedToInt(span->blue);
+ color[ACOMP] = FixedToInt(span->alpha);
+ for (i = 0; i < n; i++) {
+ COPY_4V(rgba[i], color);
+ }
+ }
+ else {
+ GLushort (*rgba)[4] = span->array->rgba16;
+ GLfixed r, g, b, a;
+ GLint dr, dg, db, da;
+ r = span->red;
+ g = span->green;
+ b = span->blue;
+ a = span->alpha;
+ dr = span->redStep;
+ dg = span->greenStep;
+ db = span->blueStep;
+ da = span->alphaStep;
+ for (i = 0; i < n; i++) {
+ rgba[i][RCOMP] = FixedToChan(r);
+ rgba[i][GCOMP] = FixedToChan(g);
+ rgba[i][BCOMP] = FixedToChan(b);
+ rgba[i][ACOMP] = FixedToChan(a);
+ r += dr;
+ g += dg;
+ b += db;
+ a += da;
+ }
+ }
+ }
+ break;
+#endif
+ case GL_FLOAT:
+ interpolate_active_attribs(ctx, span, FRAG_BIT_COL0);
+ break;
+ default:
+ _mesa_problem(ctx, "bad datatype 0x%x in interpolate_int_colors",
+ span->array->ChanType);
+ }
+ span->arrayMask |= SPAN_RGBA;
+}
+
+
+/**
+ * Populate the FRAG_ATTRIB_COL0 array.
+ */
+static INLINE void
+interpolate_float_colors(SWspan *span)
+{
+ GLfloat (*col0)[4] = span->array->attribs[FRAG_ATTRIB_COL0];
+ const GLuint n = span->end;
+ GLuint i;
+
+ assert(!(span->arrayAttribs & FRAG_BIT_COL0));
+
+ if (span->arrayMask & SPAN_RGBA) {
+ /* convert array of int colors */
+ for (i = 0; i < n; i++) {
+ col0[i][0] = UBYTE_TO_FLOAT(span->array->rgba8[i][0]);
+ col0[i][1] = UBYTE_TO_FLOAT(span->array->rgba8[i][1]);
+ col0[i][2] = UBYTE_TO_FLOAT(span->array->rgba8[i][2]);
+ col0[i][3] = UBYTE_TO_FLOAT(span->array->rgba8[i][3]);
+ }
+ }
+ else {
+ /* interpolate red/green/blue/alpha to get float colors */
+ ASSERT(span->interpMask & SPAN_RGBA);
+ if (span->interpMask & SPAN_FLAT) {
+ GLfloat r = FixedToFloat(span->red);
+ GLfloat g = FixedToFloat(span->green);
+ GLfloat b = FixedToFloat(span->blue);
+ GLfloat a = FixedToFloat(span->alpha);
+ for (i = 0; i < n; i++) {
+ ASSIGN_4V(col0[i], r, g, b, a);
+ }
+ }
+ else {
+ GLfloat r = FixedToFloat(span->red);
+ GLfloat g = FixedToFloat(span->green);
+ GLfloat b = FixedToFloat(span->blue);
+ GLfloat a = FixedToFloat(span->alpha);
+ GLfloat dr = FixedToFloat(span->redStep);
+ GLfloat dg = FixedToFloat(span->greenStep);
+ GLfloat db = FixedToFloat(span->blueStep);
+ GLfloat da = FixedToFloat(span->alphaStep);
+ for (i = 0; i < n; i++) {
+ col0[i][0] = r;
+ col0[i][1] = g;
+ col0[i][2] = b;
+ col0[i][3] = a;
+ r += dr;
+ g += dg;
+ b += db;
+ a += da;
+ }
+ }
+ }
+
+ span->arrayAttribs |= FRAG_BIT_COL0;
+ span->array->ChanType = GL_FLOAT;
+}
+
+
+
+/**
+ * Fill in the span.zArray array from the span->z, zStep values.
+ */
+void
+_swrast_span_interpolate_z( const struct gl_context *ctx, SWspan *span )
+{
+ const GLuint n = span->end;
+ GLuint i;
+
+ ASSERT(!(span->arrayMask & SPAN_Z));
+
+ if (ctx->DrawBuffer->Visual.depthBits <= 16) {
+ GLfixed zval = span->z;
+ GLuint *z = span->array->z;
+ for (i = 0; i < n; i++) {
+ z[i] = FixedToInt(zval);
+ zval += span->zStep;
+ }
+ }
+ else {
+ /* Deep Z buffer, no fixed->int shift */
+ GLuint zval = span->z;
+ GLuint *z = span->array->z;
+ for (i = 0; i < n; i++) {
+ z[i] = zval;
+ zval += span->zStep;
+ }
+ }
+ span->interpMask &= ~SPAN_Z;
+ span->arrayMask |= SPAN_Z;
+}
+
+
+/**
+ * Compute mipmap LOD from partial derivatives.
+ * This the ideal solution, as given in the OpenGL spec.
+ */
+GLfloat
+_swrast_compute_lambda(GLfloat dsdx, GLfloat dsdy, GLfloat dtdx, GLfloat dtdy,
+ GLfloat dqdx, GLfloat dqdy, GLfloat texW, GLfloat texH,
+ GLfloat s, GLfloat t, GLfloat q, GLfloat invQ)
+{
+ GLfloat dudx = texW * ((s + dsdx) / (q + dqdx) - s * invQ);
+ GLfloat dvdx = texH * ((t + dtdx) / (q + dqdx) - t * invQ);
+ GLfloat dudy = texW * ((s + dsdy) / (q + dqdy) - s * invQ);
+ GLfloat dvdy = texH * ((t + dtdy) / (q + dqdy) - t * invQ);
+ GLfloat x = SQRTF(dudx * dudx + dvdx * dvdx);
+ GLfloat y = SQRTF(dudy * dudy + dvdy * dvdy);
+ GLfloat rho = MAX2(x, y);
+ GLfloat lambda = LOG2(rho);
+ return lambda;
+}
+
+
+/**
+ * Compute mipmap LOD from partial derivatives.
+ * This is a faster approximation than above function.
+ */
+#if 0
+GLfloat
+_swrast_compute_lambda(GLfloat dsdx, GLfloat dsdy, GLfloat dtdx, GLfloat dtdy,
+ GLfloat dqdx, GLfloat dqdy, GLfloat texW, GLfloat texH,
+ GLfloat s, GLfloat t, GLfloat q, GLfloat invQ)
+{
+ GLfloat dsdx2 = (s + dsdx) / (q + dqdx) - s * invQ;
+ GLfloat dtdx2 = (t + dtdx) / (q + dqdx) - t * invQ;
+ GLfloat dsdy2 = (s + dsdy) / (q + dqdy) - s * invQ;
+ GLfloat dtdy2 = (t + dtdy) / (q + dqdy) - t * invQ;
+ GLfloat maxU, maxV, rho, lambda;
+ dsdx2 = FABSF(dsdx2);
+ dsdy2 = FABSF(dsdy2);
+ dtdx2 = FABSF(dtdx2);
+ dtdy2 = FABSF(dtdy2);
+ maxU = MAX2(dsdx2, dsdy2) * texW;
+ maxV = MAX2(dtdx2, dtdy2) * texH;
+ rho = MAX2(maxU, maxV);
+ lambda = LOG2(rho);
+ return lambda;
+}
+#endif
+
+
+/**
+ * Fill in the span.array->attrib[FRAG_ATTRIB_TEXn] arrays from the
+ * using the attrStart/Step values.
+ *
+ * This function only used during fixed-function fragment processing.
+ *
+ * Note: in the places where we divide by Q (or mult by invQ) we're
+ * really doing two things: perspective correction and texcoord
+ * projection. Remember, for texcoord (s,t,r,q) we need to index
+ * texels with (s/q, t/q, r/q).
+ */
+static void
+interpolate_texcoords(struct gl_context *ctx, SWspan *span)
+{
+ const GLuint maxUnit
+ = (ctx->Texture._EnabledCoordUnits > 1) ? ctx->Const.MaxTextureUnits : 1;
+ GLuint u;
+
+ /* XXX CoordUnits vs. ImageUnits */
+ for (u = 0; u < maxUnit; u++) {
+ if (ctx->Texture._EnabledCoordUnits & (1 << u)) {
+ const GLuint attr = FRAG_ATTRIB_TEX0 + u;
+ const struct gl_texture_object *obj = ctx->Texture.Unit[u]._Current;
+ GLfloat texW, texH;
+ GLboolean needLambda;
+ GLfloat (*texcoord)[4] = span->array->attribs[attr];
+ GLfloat *lambda = span->array->lambda[u];
+ const GLfloat dsdx = span->attrStepX[attr][0];
+ const GLfloat dsdy = span->attrStepY[attr][0];
+ const GLfloat dtdx = span->attrStepX[attr][1];
+ const GLfloat dtdy = span->attrStepY[attr][1];
+ const GLfloat drdx = span->attrStepX[attr][2];
+ const GLfloat dqdx = span->attrStepX[attr][3];
+ const GLfloat dqdy = span->attrStepY[attr][3];
+ GLfloat s = span->attrStart[attr][0] + span->leftClip * dsdx;
+ GLfloat t = span->attrStart[attr][1] + span->leftClip * dtdx;
+ GLfloat r = span->attrStart[attr][2] + span->leftClip * drdx;
+ GLfloat q = span->attrStart[attr][3] + span->leftClip * dqdx;
+
+ if (obj) {
+ const struct gl_texture_image *img = obj->Image[0][obj->BaseLevel];
+ needLambda = (obj->Sampler.MinFilter != obj->Sampler.MagFilter)
+ || ctx->FragmentProgram._Current;
+ texW = img->WidthScale;
+ texH = img->HeightScale;
+ }
+ else {
+ /* using a fragment program */
+ texW = 1.0;
+ texH = 1.0;
+ needLambda = GL_FALSE;
+ }
+
+ if (needLambda) {
+ GLuint i;
+ if (ctx->FragmentProgram._Current
+ || ctx->ATIFragmentShader._Enabled) {
+ /* do perspective correction but don't divide s, t, r by q */
+ const GLfloat dwdx = span->attrStepX[FRAG_ATTRIB_WPOS][3];
+ GLfloat w = span->attrStart[FRAG_ATTRIB_WPOS][3] + span->leftClip * dwdx;
+ for (i = 0; i < span->end; i++) {
+ const GLfloat invW = 1.0F / w;
+ texcoord[i][0] = s * invW;
+ texcoord[i][1] = t * invW;
+ texcoord[i][2] = r * invW;
+ texcoord[i][3] = q * invW;
+ lambda[i] = _swrast_compute_lambda(dsdx, dsdy, dtdx, dtdy,
+ dqdx, dqdy, texW, texH,
+ s, t, q, invW);
+ s += dsdx;
+ t += dtdx;
+ r += drdx;
+ q += dqdx;
+ w += dwdx;
+ }
+ }
+ else {
+ for (i = 0; i < span->end; i++) {
+ const GLfloat invQ = (q == 0.0F) ? 1.0F : (1.0F / q);
+ texcoord[i][0] = s * invQ;
+ texcoord[i][1] = t * invQ;
+ texcoord[i][2] = r * invQ;
+ texcoord[i][3] = q;
+ lambda[i] = _swrast_compute_lambda(dsdx, dsdy, dtdx, dtdy,
+ dqdx, dqdy, texW, texH,
+ s, t, q, invQ);
+ s += dsdx;
+ t += dtdx;
+ r += drdx;
+ q += dqdx;
+ }
+ }
+ span->arrayMask |= SPAN_LAMBDA;
+ }
+ else {
+ GLuint i;
+ if (ctx->FragmentProgram._Current ||
+ ctx->ATIFragmentShader._Enabled) {
+ /* do perspective correction but don't divide s, t, r by q */
+ const GLfloat dwdx = span->attrStepX[FRAG_ATTRIB_WPOS][3];
+ GLfloat w = span->attrStart[FRAG_ATTRIB_WPOS][3] + span->leftClip * dwdx;
+ for (i = 0; i < span->end; i++) {
+ const GLfloat invW = 1.0F / w;
+ texcoord[i][0] = s * invW;
+ texcoord[i][1] = t * invW;
+ texcoord[i][2] = r * invW;
+ texcoord[i][3] = q * invW;
+ lambda[i] = 0.0;
+ s += dsdx;
+ t += dtdx;
+ r += drdx;
+ q += dqdx;
+ w += dwdx;
+ }
+ }
+ else if (dqdx == 0.0F) {
+ /* Ortho projection or polygon's parallel to window X axis */
+ const GLfloat invQ = (q == 0.0F) ? 1.0F : (1.0F / q);
+ for (i = 0; i < span->end; i++) {
+ texcoord[i][0] = s * invQ;
+ texcoord[i][1] = t * invQ;
+ texcoord[i][2] = r * invQ;
+ texcoord[i][3] = q;
+ lambda[i] = 0.0;
+ s += dsdx;
+ t += dtdx;
+ r += drdx;
+ }
+ }
+ else {
+ for (i = 0; i < span->end; i++) {
+ const GLfloat invQ = (q == 0.0F) ? 1.0F : (1.0F / q);
+ texcoord[i][0] = s * invQ;
+ texcoord[i][1] = t * invQ;
+ texcoord[i][2] = r * invQ;
+ texcoord[i][3] = q;
+ lambda[i] = 0.0;
+ s += dsdx;
+ t += dtdx;
+ r += drdx;
+ q += dqdx;
+ }
+ }
+ } /* lambda */
+ } /* if */
+ } /* for */
+}
+
+
+/**
+ * Fill in the arrays->attribs[FRAG_ATTRIB_WPOS] array.
+ */
+static INLINE void
+interpolate_wpos(struct gl_context *ctx, SWspan *span)
+{
+ GLfloat (*wpos)[4] = span->array->attribs[FRAG_ATTRIB_WPOS];
+ GLuint i;
+ const GLfloat zScale = 1.0F / ctx->DrawBuffer->_DepthMaxF;
+ GLfloat w, dw;
+
+ if (span->arrayMask & SPAN_XY) {
+ for (i = 0; i < span->end; i++) {
+ wpos[i][0] = (GLfloat) span->array->x[i];
+ wpos[i][1] = (GLfloat) span->array->y[i];
+ }
+ }
+ else {
+ for (i = 0; i < span->end; i++) {
+ wpos[i][0] = (GLfloat) span->x + i;
+ wpos[i][1] = (GLfloat) span->y;
+ }
+ }
+
+ dw = span->attrStepX[FRAG_ATTRIB_WPOS][3];
+ w = span->attrStart[FRAG_ATTRIB_WPOS][3] + span->leftClip * dw;
+ for (i = 0; i < span->end; i++) {
+ wpos[i][2] = (GLfloat) span->array->z[i] * zScale;
+ wpos[i][3] = w;
+ w += dw;
+ }
+}
+
+
+/**
+ * Apply the current polygon stipple pattern to a span of pixels.
+ */
+static INLINE void
+stipple_polygon_span(struct gl_context *ctx, SWspan *span)
+{
+ GLubyte *mask = span->array->mask;
+
+ ASSERT(ctx->Polygon.StippleFlag);
+
+ if (span->arrayMask & SPAN_XY) {
+ /* arrays of x/y pixel coords */
+ GLuint i;
+ for (i = 0; i < span->end; i++) {
+ const GLint col = span->array->x[i] % 32;
+ const GLint row = span->array->y[i] % 32;
+ const GLuint stipple = ctx->PolygonStipple[row];
+ if (((1 << col) & stipple) == 0) {
+ mask[i] = 0;
+ }
+ }
+ }
+ else {
+ /* horizontal span of pixels */
+ const GLuint highBit = 1 << 31;
+ const GLuint stipple = ctx->PolygonStipple[span->y % 32];
+ GLuint i, m = highBit >> (GLuint) (span->x % 32);
+ for (i = 0; i < span->end; i++) {
+ if ((m & stipple) == 0) {
+ mask[i] = 0;
+ }
+ m = m >> 1;
+ if (m == 0) {
+ m = highBit;
+ }
+ }
+ }
+ span->writeAll = GL_FALSE;
+}
+
+
+/**
+ * Clip a pixel span to the current buffer/window boundaries:
+ * DrawBuffer->_Xmin, _Xmax, _Ymin, _Ymax. This will accomplish
+ * window clipping and scissoring.
+ * Return: GL_TRUE some pixels still visible
+ * GL_FALSE nothing visible
+ */
+static INLINE GLuint
+clip_span( struct gl_context *ctx, SWspan *span )
+{
+ const GLint xmin = ctx->DrawBuffer->_Xmin;
+ const GLint xmax = ctx->DrawBuffer->_Xmax;
+ const GLint ymin = ctx->DrawBuffer->_Ymin;
+ const GLint ymax = ctx->DrawBuffer->_Ymax;
+
+ span->leftClip = 0;
+
+ if (span->arrayMask & SPAN_XY) {
+ /* arrays of x/y pixel coords */
+ const GLint *x = span->array->x;
+ const GLint *y = span->array->y;
+ const GLint n = span->end;
+ GLubyte *mask = span->array->mask;
+ GLint i;
+ if (span->arrayMask & SPAN_MASK) {
+ /* note: using & intead of && to reduce branches */
+ for (i = 0; i < n; i++) {
+ mask[i] &= (x[i] >= xmin) & (x[i] < xmax)
+ & (y[i] >= ymin) & (y[i] < ymax);
+ }
+ }
+ else {
+ /* note: using & intead of && to reduce branches */
+ for (i = 0; i < n; i++) {
+ mask[i] = (x[i] >= xmin) & (x[i] < xmax)
+ & (y[i] >= ymin) & (y[i] < ymax);
+ }
+ }
+ return GL_TRUE; /* some pixels visible */
+ }
+ else {
+ /* horizontal span of pixels */
+ const GLint x = span->x;
+ const GLint y = span->y;
+ GLint n = span->end;
+
+ /* Trivial rejection tests */
+ if (y < ymin || y >= ymax || x + n <= xmin || x >= xmax) {
+ span->end = 0;
+ return GL_FALSE; /* all pixels clipped */
+ }
+
+ /* Clip to right */
+ if (x + n > xmax) {
+ ASSERT(x < xmax);
+ n = span->end = xmax - x;
+ }
+
+ /* Clip to the left */
+ if (x < xmin) {
+ const GLint leftClip = xmin - x;
+ GLuint i;
+
+ ASSERT(leftClip > 0);
+ ASSERT(x + n > xmin);
+
+ /* Clip 'leftClip' pixels from the left side.
+ * The span->leftClip field will be applied when we interpolate
+ * fragment attributes.
+ * For arrays of values, shift them left.
+ */
+ for (i = 0; i < FRAG_ATTRIB_MAX; i++) {
+ if (span->interpMask & (1 << i)) {
+ GLuint j;
+ for (j = 0; j < 4; j++) {
+ span->attrStart[i][j] += leftClip * span->attrStepX[i][j];
+ }
+ }
+ }
+
+ span->red += leftClip * span->redStep;
+ span->green += leftClip * span->greenStep;
+ span->blue += leftClip * span->blueStep;
+ span->alpha += leftClip * span->alphaStep;
+ span->index += leftClip * span->indexStep;
+ span->z += leftClip * span->zStep;
+ span->intTex[0] += leftClip * span->intTexStep[0];
+ span->intTex[1] += leftClip * span->intTexStep[1];
+
+#define SHIFT_ARRAY(ARRAY, SHIFT, LEN) \
+ memcpy(ARRAY, ARRAY + (SHIFT), (LEN) * sizeof(ARRAY[0]))
+
+ for (i = 0; i < FRAG_ATTRIB_MAX; i++) {
+ if (span->arrayAttribs & (1 << i)) {
+ /* shift array elements left by 'leftClip' */
+ SHIFT_ARRAY(span->array->attribs[i], leftClip, n - leftClip);
+ }
+ }
+
+ SHIFT_ARRAY(span->array->mask, leftClip, n - leftClip);
+ SHIFT_ARRAY(span->array->rgba8, leftClip, n - leftClip);
+ SHIFT_ARRAY(span->array->rgba16, leftClip, n - leftClip);
+ SHIFT_ARRAY(span->array->x, leftClip, n - leftClip);
+ SHIFT_ARRAY(span->array->y, leftClip, n - leftClip);
+ SHIFT_ARRAY(span->array->z, leftClip, n - leftClip);
+ SHIFT_ARRAY(span->array->index, leftClip, n - leftClip);
+ for (i = 0; i < MAX_TEXTURE_COORD_UNITS; i++) {
+ SHIFT_ARRAY(span->array->lambda[i], leftClip, n - leftClip);
+ }
+ SHIFT_ARRAY(span->array->coverage, leftClip, n - leftClip);
+
+#undef SHIFT_ARRAY
+
+ span->leftClip = leftClip;
+ span->x = xmin;
+ span->end -= leftClip;
+ span->writeAll = GL_FALSE;
+ }
+
+ ASSERT(span->x >= xmin);
+ ASSERT(span->x + span->end <= xmax);
+ ASSERT(span->y >= ymin);
+ ASSERT(span->y < ymax);
+
+ return GL_TRUE; /* some pixels visible */
+ }
+}
+
+
+/**
+ * Add specular colors to primary colors.
+ * Only called during fixed-function operation.
+ * Result is float color array (FRAG_ATTRIB_COL0).
+ */
+static INLINE void
+add_specular(struct gl_context *ctx, SWspan *span)
+{
+ const SWcontext *swrast = SWRAST_CONTEXT(ctx);
+ const GLubyte *mask = span->array->mask;
+ GLfloat (*col0)[4] = span->array->attribs[FRAG_ATTRIB_COL0];
+ GLfloat (*col1)[4] = span->array->attribs[FRAG_ATTRIB_COL1];
+ GLuint i;
+
+ ASSERT(!ctx->FragmentProgram._Current);
+ ASSERT(span->arrayMask & SPAN_RGBA);
+ ASSERT(swrast->_ActiveAttribMask & FRAG_BIT_COL1);
+ (void) swrast; /* silence warning */
+
+ if (span->array->ChanType == GL_FLOAT) {
+ if ((span->arrayAttribs & FRAG_BIT_COL0) == 0) {
+ interpolate_active_attribs(ctx, span, FRAG_BIT_COL0);
+ }
+ }
+ else {
+ /* need float colors */
+ if ((span->arrayAttribs & FRAG_BIT_COL0) == 0) {
+ interpolate_float_colors(span);
+ }
+ }
+
+ if ((span->arrayAttribs & FRAG_BIT_COL1) == 0) {
+ /* XXX could avoid this and interpolate COL1 in the loop below */
+ interpolate_active_attribs(ctx, span, FRAG_BIT_COL1);
+ }
+
+ ASSERT(span->arrayAttribs & FRAG_BIT_COL0);
+ ASSERT(span->arrayAttribs & FRAG_BIT_COL1);
+
+ for (i = 0; i < span->end; i++) {
+ if (mask[i]) {
+ col0[i][0] += col1[i][0];
+ col0[i][1] += col1[i][1];
+ col0[i][2] += col1[i][2];
+ }
+ }
+
+ span->array->ChanType = GL_FLOAT;
+}
+
+
+/**
+ * Apply antialiasing coverage value to alpha values.
+ */
+static INLINE void
+apply_aa_coverage(SWspan *span)
+{
+ const GLfloat *coverage = span->array->coverage;
+ GLuint i;
+ if (span->array->ChanType == GL_UNSIGNED_BYTE) {
+ GLubyte (*rgba)[4] = span->array->rgba8;
+ for (i = 0; i < span->end; i++) {
+ const GLfloat a = rgba[i][ACOMP] * coverage[i];
+ rgba[i][ACOMP] = (GLubyte) CLAMP(a, 0.0, 255.0);
+ ASSERT(coverage[i] >= 0.0);
+ ASSERT(coverage[i] <= 1.0);
+ }
+ }
+ else if (span->array->ChanType == GL_UNSIGNED_SHORT) {
+ GLushort (*rgba)[4] = span->array->rgba16;
+ for (i = 0; i < span->end; i++) {
+ const GLfloat a = rgba[i][ACOMP] * coverage[i];
+ rgba[i][ACOMP] = (GLushort) CLAMP(a, 0.0, 65535.0);
+ }
+ }
+ else {
+ GLfloat (*rgba)[4] = span->array->attribs[FRAG_ATTRIB_COL0];
+ for (i = 0; i < span->end; i++) {
+ rgba[i][ACOMP] = rgba[i][ACOMP] * coverage[i];
+ /* clamp later */
+ }
+ }
+}
+
+
+/**
+ * Clamp span's float colors to [0,1]
+ */
+static INLINE void
+clamp_colors(SWspan *span)
+{
+ GLfloat (*rgba)[4] = span->array->attribs[FRAG_ATTRIB_COL0];
+ GLuint i;
+ ASSERT(span->array->ChanType == GL_FLOAT);
+ for (i = 0; i < span->end; i++) {
+ rgba[i][RCOMP] = CLAMP(rgba[i][RCOMP], 0.0F, 1.0F);
+ rgba[i][GCOMP] = CLAMP(rgba[i][GCOMP], 0.0F, 1.0F);
+ rgba[i][BCOMP] = CLAMP(rgba[i][BCOMP], 0.0F, 1.0F);
+ rgba[i][ACOMP] = CLAMP(rgba[i][ACOMP], 0.0F, 1.0F);
+ }
+}
+
+
+/**
+ * Convert the span's color arrays to the given type.
+ * The only way 'output' can be greater than zero is when we have a fragment
+ * program that writes to gl_FragData[1] or higher.
+ * \param output which fragment program color output is being processed
+ */
+static INLINE void
+convert_color_type(SWspan *span, GLenum newType, GLuint output)
+{
+ GLvoid *src, *dst;
+
+ if (output > 0 || span->array->ChanType == GL_FLOAT) {
+ src = span->array->attribs[FRAG_ATTRIB_COL0 + output];
+ span->array->ChanType = GL_FLOAT;
+ }
+ else if (span->array->ChanType == GL_UNSIGNED_BYTE) {
+ src = span->array->rgba8;
+ }
+ else {
+ ASSERT(span->array->ChanType == GL_UNSIGNED_SHORT);
+ src = span->array->rgba16;
+ }
+
+ if (newType == GL_UNSIGNED_BYTE) {
+ dst = span->array->rgba8;
+ }
+ else if (newType == GL_UNSIGNED_SHORT) {
+ dst = span->array->rgba16;
+ }
+ else {
+ dst = span->array->attribs[FRAG_ATTRIB_COL0];
+ }
+
+ _mesa_convert_colors(span->array->ChanType, src,
+ newType, dst,
+ span->end, span->array->mask);
+
+ span->array->ChanType = newType;
+ span->array->rgba = dst;
+}
+
+
+
+/**
+ * Apply fragment shader, fragment program or normal texturing to span.
+ */
+static INLINE void
+shade_texture_span(struct gl_context *ctx, SWspan *span)
+{
+ GLbitfield inputsRead;
+
+ /* Determine which fragment attributes are actually needed */
+ if (ctx->FragmentProgram._Current) {
+ inputsRead = ctx->FragmentProgram._Current->Base.InputsRead;
+ }
+ else {
+ /* XXX we could be a bit smarter about this */
+ inputsRead = ~0;
+ }
+
+ if (ctx->FragmentProgram._Current ||
+ ctx->ATIFragmentShader._Enabled) {
+ /* programmable shading */
+ if (span->primitive == GL_BITMAP && span->array->ChanType != GL_FLOAT) {
+ convert_color_type(span, GL_FLOAT, 0);
+ }
+ else {
+ span->array->rgba = (void *) span->array->attribs[FRAG_ATTRIB_COL0];
+ }
+
+ if (span->primitive != GL_POINT ||
+ (span->interpMask & SPAN_RGBA) ||
+ ctx->Point.PointSprite) {
+ /* for single-pixel points, we populated the arrays already */
+ interpolate_active_attribs(ctx, span, ~0);
+ }
+ span->array->ChanType = GL_FLOAT;
+
+ if (!(span->arrayMask & SPAN_Z))
+ _swrast_span_interpolate_z (ctx, span);
+
+#if 0
+ if (inputsRead & FRAG_BIT_WPOS)
+#else
+ /* XXX always interpolate wpos so that DDX/DDY work */
+#endif
+ interpolate_wpos(ctx, span);
+
+ /* Run fragment program/shader now */
+ if (ctx->FragmentProgram._Current) {
+ _swrast_exec_fragment_program(ctx, span);
+ }
+ else {
+ ASSERT(ctx->ATIFragmentShader._Enabled);
+ _swrast_exec_fragment_shader(ctx, span);
+ }
+ }
+ else if (ctx->Texture._EnabledCoordUnits) {
+ /* conventional texturing */
+
+#if CHAN_BITS == 32
+ if ((span->arrayAttribs & FRAG_BIT_COL0) == 0) {
+ interpolate_int_colors(ctx, span);
+ }
+#else
+ if (!(span->arrayMask & SPAN_RGBA))
+ interpolate_int_colors(ctx, span);
+#endif
+ if ((span->arrayAttribs & FRAG_BITS_TEX_ANY) == 0x0)
+ interpolate_texcoords(ctx, span);
+
+ _swrast_texture_span(ctx, span);
+ }
+}
+
+
+
+/**
+ * Apply all the per-fragment operations to a span.
+ * This now includes texturing (_swrast_write_texture_span() is history).
+ * This function may modify any of the array values in the span.
+ * span->interpMask and span->arrayMask may be changed but will be restored
+ * to their original values before returning.
+ */
+void
+_swrast_write_rgba_span( struct gl_context *ctx, SWspan *span)
+{
+ const SWcontext *swrast = SWRAST_CONTEXT(ctx);
+ const GLuint *colorMask = (GLuint *) ctx->Color.ColorMask;
+ const GLbitfield origInterpMask = span->interpMask;
+ const GLbitfield origArrayMask = span->arrayMask;
+ const GLbitfield origArrayAttribs = span->arrayAttribs;
+ const GLenum origChanType = span->array->ChanType;
+ void * const origRgba = span->array->rgba;
+ const GLboolean shader = (ctx->FragmentProgram._Current
+ || ctx->ATIFragmentShader._Enabled);
+ const GLboolean shaderOrTexture = shader || ctx->Texture._EnabledCoordUnits;
+ struct gl_framebuffer *fb = ctx->DrawBuffer;
+
+ /*
+ printf("%s() interp 0x%x array 0x%x\n", __FUNCTION__,
+ span->interpMask, span->arrayMask);
+ */
+
+ ASSERT(span->primitive == GL_POINT ||
+ span->primitive == GL_LINE ||
+ span->primitive == GL_POLYGON ||
+ span->primitive == GL_BITMAP);
+
+ /* Fragment write masks */
+ if (span->arrayMask & SPAN_MASK) {
+ /* mask was initialized by caller, probably glBitmap */
+ span->writeAll = GL_FALSE;
+ }
+ else {
+ memset(span->array->mask, 1, span->end);
+ span->writeAll = GL_TRUE;
+ }
+
+ /* Clip to window/scissor box */
+ if (!clip_span(ctx, span)) {
+ return;
+ }
+
+ ASSERT(span->end <= MAX_WIDTH);
+
+ /* Depth bounds test */
+ if (ctx->Depth.BoundsTest && fb->Visual.depthBits > 0) {
+ if (!_swrast_depth_bounds_test(ctx, span)) {
+ return;
+ }
+ }
+
+#ifdef DEBUG
+ /* Make sure all fragments are within window bounds */
+ if (span->arrayMask & SPAN_XY) {
+ /* array of pixel locations */
+ GLuint i;
+ for (i = 0; i < span->end; i++) {
+ if (span->array->mask[i]) {
+ assert(span->array->x[i] >= fb->_Xmin);
+ assert(span->array->x[i] < fb->_Xmax);
+ assert(span->array->y[i] >= fb->_Ymin);
+ assert(span->array->y[i] < fb->_Ymax);
+ }
+ }
+ }
+#endif
+
+ /* Polygon Stippling */
+ if (ctx->Polygon.StippleFlag && span->primitive == GL_POLYGON) {
+ stipple_polygon_span(ctx, span);
+ }
+
+ /* This is the normal place to compute the fragment color/Z
+ * from texturing or shading.
+ */
+ if (shaderOrTexture && !swrast->_DeferredTexture) {
+ shade_texture_span(ctx, span);
+ }
+
+ /* Do the alpha test */
+ if (ctx->Color.AlphaEnabled) {
+ if (!_swrast_alpha_test(ctx, span)) {
+ /* all fragments failed test */
+ goto end;
+ }
+ }
+
+ /* Stencil and Z testing */
+ if (ctx->Stencil._Enabled || ctx->Depth.Test) {
+ if (!(span->arrayMask & SPAN_Z))
+ _swrast_span_interpolate_z(ctx, span);
+
+ if (ctx->Transform.DepthClamp)
+ _swrast_depth_clamp_span(ctx, span);
+
+ if (ctx->Stencil._Enabled) {
+ /* Combined Z/stencil tests */
+ if (!_swrast_stencil_and_ztest_span(ctx, span)) {
+ /* all fragments failed test */
+ goto end;
+ }
+ }
+ else if (fb->Visual.depthBits > 0) {
+ /* Just regular depth testing */
+ ASSERT(ctx->Depth.Test);
+ ASSERT(span->arrayMask & SPAN_Z);
+ if (!_swrast_depth_test_span(ctx, span)) {
+ /* all fragments failed test */
+ goto end;
+ }
+ }
+ }
+
+ if (ctx->Query.CurrentOcclusionObject) {
+ /* update count of 'passed' fragments */
+ struct gl_query_object *q = ctx->Query.CurrentOcclusionObject;
+ GLuint i;
+ for (i = 0; i < span->end; i++)
+ q->Result += span->array->mask[i];
+ }
+
+ /* We had to wait until now to check for glColorMask(0,0,0,0) because of
+ * the occlusion test.
+ */
+ if (fb->_NumColorDrawBuffers == 1 && colorMask[0] == 0x0) {
+ /* no colors to write */
+ goto end;
+ }
+
+ /* If we were able to defer fragment color computation to now, there's
+ * a good chance that many fragments will have already been killed by
+ * Z/stencil testing.
+ */
+ if (shaderOrTexture && swrast->_DeferredTexture) {
+ shade_texture_span(ctx, span);
+ }
+
+#if CHAN_BITS == 32
+ if ((span->arrayAttribs & FRAG_BIT_COL0) == 0) {
+ interpolate_active_attribs(ctx, span, FRAG_BIT_COL0);
+ }
+#else
+ if ((span->arrayMask & SPAN_RGBA) == 0) {
+ interpolate_int_colors(ctx, span);
+ }
+#endif
+
+ ASSERT(span->arrayMask & SPAN_RGBA);
+
+ if (span->primitive == GL_BITMAP || !swrast->SpecularVertexAdd) {
+ /* Add primary and specular (diffuse + specular) colors */
+ if (!shader) {
+ if (ctx->Fog.ColorSumEnabled ||
+ (ctx->Light.Enabled &&
+ ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)) {
+ add_specular(ctx, span);
+ }
+ }
+ }
+
+ /* Fog */
+ if (swrast->_FogEnabled) {
+ _swrast_fog_rgba_span(ctx, span);
+ }
+
+ /* Antialias coverage application */
+ if (span->arrayMask & SPAN_COVERAGE) {
+ apply_aa_coverage(span);
+ }
+
+ /* Clamp color/alpha values over the range [0.0, 1.0] before storage */
+ if (ctx->Color.ClampFragmentColor == GL_TRUE &&
+ span->array->ChanType == GL_FLOAT) {
+ clamp_colors(span);
+ }
+
+ /*
+ * Write to renderbuffers.
+ * Depending on glDrawBuffer() state and the which color outputs are
+ * written by the fragment shader, we may either replicate one color to
+ * all renderbuffers or write a different color to each renderbuffer.
+ * multiFragOutputs=TRUE for the later case.
+ */
+ {
+ const GLuint numBuffers = fb->_NumColorDrawBuffers;
+ const struct gl_fragment_program *fp = ctx->FragmentProgram._Current;
+ const GLboolean multiFragOutputs =
+ (fp && fp->Base.OutputsWritten >= (1 << FRAG_RESULT_DATA0));
+ GLuint buf;
+
+ for (buf = 0; buf < numBuffers; buf++) {
+ struct gl_renderbuffer *rb = fb->_ColorDrawBuffers[buf];
+
+ /* color[fragOutput] will be written to buffer[buf] */
+
+ if (rb) {
+ GLchan rgbaSave[MAX_WIDTH][4];
+ const GLuint fragOutput = multiFragOutputs ? buf : 0;
+
+ /* set span->array->rgba to colors for render buffer's datatype */
+ if (rb->DataType != span->array->ChanType || fragOutput > 0) {
+ convert_color_type(span, rb->DataType, fragOutput);
+ }
+ else {
+ if (rb->DataType == GL_UNSIGNED_BYTE) {
+ span->array->rgba = span->array->rgba8;
+ }
+ else if (rb->DataType == GL_UNSIGNED_SHORT) {
+ span->array->rgba = (void *) span->array->rgba16;
+ }
+ else {
+ span->array->rgba = (void *)
+ span->array->attribs[FRAG_ATTRIB_COL0];
+ }
+ }
+
+ if (!multiFragOutputs && numBuffers > 1) {
+ /* save colors for second, third renderbuffer writes */
+ memcpy(rgbaSave, span->array->rgba,
+ 4 * span->end * sizeof(GLchan));
+ }
+
+ ASSERT(rb->_BaseFormat == GL_RGBA || rb->_BaseFormat == GL_RGB ||
+ rb->_BaseFormat == GL_ALPHA);
+
+ if (ctx->Color._LogicOpEnabled) {
+ _swrast_logicop_rgba_span(ctx, rb, span);
+ }
+ else if ((ctx->Color.BlendEnabled >> buf) & 1) {
+ _swrast_blend_span(ctx, rb, span);
+ }
+
+ if (colorMask[buf] != 0xffffffff) {
+ _swrast_mask_rgba_span(ctx, rb, span, buf);
+ }
+
+ if (span->arrayMask & SPAN_XY) {
+ /* array of pixel coords */
+ ASSERT(rb->PutValues);
+ rb->PutValues(ctx, rb, span->end,
+ span->array->x, span->array->y,
+ span->array->rgba, span->array->mask);
+ }
+ else {
+ /* horizontal run of pixels */
+ ASSERT(rb->PutRow);
+ rb->PutRow(ctx, rb, span->end, span->x, span->y,
+ span->array->rgba,
+ span->writeAll ? NULL: span->array->mask);
+ }
+
+ if (!multiFragOutputs && numBuffers > 1) {
+ /* restore original span values */
+ memcpy(span->array->rgba, rgbaSave,
+ 4 * span->end * sizeof(GLchan));
+ }
+
+ } /* if rb */
+ } /* for buf */
+ }
+
+end:
+ /* restore these values before returning */
+ span->interpMask = origInterpMask;
+ span->arrayMask = origArrayMask;
+ span->arrayAttribs = origArrayAttribs;
+ span->array->ChanType = origChanType;
+ span->array->rgba = origRgba;
+}
+
+
+/**
+ * Read RGBA pixels from a renderbuffer. Clipping will be done to prevent
+ * reading ouside the buffer's boundaries.
+ * \param dstType datatype for returned colors
+ * \param rgba the returned colors
+ */
+void
+_swrast_read_rgba_span( struct gl_context *ctx, struct gl_renderbuffer *rb,
+ GLuint n, GLint x, GLint y, GLenum dstType,
+ GLvoid *rgba)
+{
+ const GLint bufWidth = (GLint) rb->Width;
+ const GLint bufHeight = (GLint) rb->Height;
+
+ if (y < 0 || y >= bufHeight || x + (GLint) n < 0 || x >= bufWidth) {
+ /* completely above, below, or right */
+ /* XXX maybe leave rgba values undefined? */
+ memset(rgba, 0, 4 * n * sizeof(GLchan));
+ }
+ else {
+ GLint skip, length;
+ if (x < 0) {
+ /* left edge clipping */
+ skip = -x;
+ length = (GLint) n - skip;
+ if (length < 0) {
+ /* completely left of window */
+ return;
+ }
+ if (length > bufWidth) {
+ length = bufWidth;
+ }
+ }
+ else if ((GLint) (x + n) > bufWidth) {
+ /* right edge clipping */
+ skip = 0;
+ length = bufWidth - x;
+ if (length < 0) {
+ /* completely to right of window */
+ return;
+ }
+ }
+ else {
+ /* no clipping */
+ skip = 0;
+ length = (GLint) n;
+ }
+
+ ASSERT(rb);
+ ASSERT(rb->GetRow);
+ ASSERT(rb->_BaseFormat == GL_RGB || rb->_BaseFormat == GL_RGBA ||
+ rb->_BaseFormat == GL_ALPHA);
+
+ if (rb->DataType == dstType) {
+ rb->GetRow(ctx, rb, length, x + skip, y,
+ (GLubyte *) rgba + skip * RGBA_PIXEL_SIZE(rb->DataType));
+ }
+ else {
+ GLuint temp[MAX_WIDTH * 4];
+ rb->GetRow(ctx, rb, length, x + skip, y, temp);
+ _mesa_convert_colors(rb->DataType, temp,
+ dstType, (GLubyte *) rgba + skip * RGBA_PIXEL_SIZE(dstType),
+ length, NULL);
+ }
+ }
+}
+
+
+/**
+ * Wrapper for gl_renderbuffer::GetValues() which does clipping to avoid
+ * reading values outside the buffer bounds.
+ * We can use this for reading any format/type of renderbuffer.
+ * \param valueSize is the size in bytes of each value (pixel) put into the
+ * values array.
+ */
+void
+_swrast_get_values(struct gl_context *ctx, struct gl_renderbuffer *rb,
+ GLuint count, const GLint x[], const GLint y[],
+ void *values, GLuint valueSize)
+{
+ GLuint i, inCount = 0, inStart = 0;
+
+ for (i = 0; i < count; i++) {
+ if (x[i] >= 0 && y[i] >= 0 &&
+ x[i] < (GLint) rb->Width && y[i] < (GLint) rb->Height) {
+ /* inside */
+ if (inCount == 0)
+ inStart = i;
+ inCount++;
+ }
+ else {
+ if (inCount > 0) {
+ /* read [inStart, inStart + inCount) */
+ rb->GetValues(ctx, rb, inCount, x + inStart, y + inStart,
+ (GLubyte *) values + inStart * valueSize);
+ inCount = 0;
+ }
+ }
+ }
+ if (inCount > 0) {
+ /* read last values */
+ rb->GetValues(ctx, rb, inCount, x + inStart, y + inStart,
+ (GLubyte *) values + inStart * valueSize);
+ }
+}
+
+
+/**
+ * Wrapper for gl_renderbuffer::PutRow() which does clipping.
+ * \param valueSize size of each value (pixel) in bytes
+ */
+void
+_swrast_put_row(struct gl_context *ctx, struct gl_renderbuffer *rb,
+ GLuint count, GLint x, GLint y,
+ const GLvoid *values, GLuint valueSize)
+{
+ GLint skip = 0;
+
+ if (y < 0 || y >= (GLint) rb->Height)
+ return; /* above or below */
+
+ if (x + (GLint) count <= 0 || x >= (GLint) rb->Width)
+ return; /* entirely left or right */
+
+ if ((GLint) (x + count) > (GLint) rb->Width) {
+ /* right clip */
+ GLint clip = x + count - rb->Width;
+ count -= clip;
+ }
+
+ if (x < 0) {
+ /* left clip */
+ skip = -x;
+ x = 0;
+ count -= skip;
+ }
+
+ rb->PutRow(ctx, rb, count, x, y,
+ (const GLubyte *) values + skip * valueSize, NULL);
+}
+
+
+/**
+ * Wrapper for gl_renderbuffer::GetRow() which does clipping.
+ * \param valueSize size of each value (pixel) in bytes
+ */
+void
+_swrast_get_row(struct gl_context *ctx, struct gl_renderbuffer *rb,
+ GLuint count, GLint x, GLint y,
+ GLvoid *values, GLuint valueSize)
+{
+ GLint skip = 0;
+
+ if (y < 0 || y >= (GLint) rb->Height)
+ return; /* above or below */
+
+ if (x + (GLint) count <= 0 || x >= (GLint) rb->Width)
+ return; /* entirely left or right */
+
+ if (x + count > rb->Width) {
+ /* right clip */
+ GLint clip = x + count - rb->Width;
+ count -= clip;
+ }
+
+ if (x < 0) {
+ /* left clip */
+ skip = -x;
+ x = 0;
+ count -= skip;
+ }
+
+ rb->GetRow(ctx, rb, count, x, y, (GLubyte *) values + skip * valueSize);
+}
+
+
+/**
+ * Get RGBA pixels from the given renderbuffer.
+ * Used by blending, logicop and masking functions.
+ * \return pointer to the colors we read.
+ */
+void *
+_swrast_get_dest_rgba(struct gl_context *ctx, struct gl_renderbuffer *rb,
+ SWspan *span)
+{
+ const GLuint pixelSize = RGBA_PIXEL_SIZE(span->array->ChanType);
+ void *rbPixels;
+
+ /* Point rbPixels to a temporary space */
+ rbPixels = span->array->attribs[FRAG_ATTRIB_MAX - 1];
+
+ /* Get destination values from renderbuffer */
+ if (span->arrayMask & SPAN_XY) {
+ _swrast_get_values(ctx, rb, span->end, span->array->x, span->array->y,
+ rbPixels, pixelSize);
+ }
+ else {
+ _swrast_get_row(ctx, rb, span->end, span->x, span->y,
+ rbPixels, pixelSize);
+ }
+
+ return rbPixels;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-27 22:50:11 +0000