svn merge ^/branches/released . --username marha

1 files changed, 1002 insertions, 0 deletions

diff --git a/mesalib/src/mesa/swrast/s_blend.c b/mesalib/src/mesa/swrast/s_blend.c
new file mode 100644
index 000000000..95c83432a
--- /dev/null
+++ b/mesalib/src/mesa/swrast/s_blend.c
@@ -0,0 +1,1002 @@
+/*
+ * Mesa 3-D graphics library
+ * Version:  7.1
+ *
+ * Copyright (C) 1999-2008  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.
+ */
+
+
+/**
+ * \file swrast/s_blend.c
+ * \brief software blending.
+ * \author Brian Paul
+ *
+ * Only a few blend modes have been optimized (min, max, transparency, add)
+ * more optimized cases can easily be added if needed.
+ * Celestia uses glBlendFunc(GL_SRC_ALPHA, GL_ONE), for example.
+ */
+
+
+
+#include "main/glheader.h"
+#include "main/context.h"
+#include "main/colormac.h"
+#include "main/macros.h"
+
+#include "s_blend.h"
+#include "s_context.h"
+#include "s_span.h"
+
+
+#if defined(USE_MMX_ASM)
+#include "x86/mmx.h"
+#include "x86/common_x86_asm.h"
+#define _BLENDAPI _ASMAPI
+#else
+#define _BLENDAPI
+#endif
+
+
+/**
+ * Integer divide by 255
+ * Declare "int divtemp" before using.
+ * This satisfies Glean and should be reasonably fast.
+ * Contributed by Nathan Hand.
+ */
+#define DIV255(X)  (divtemp = (X), ((divtemp << 8) + divtemp + 256) >> 16)
+
+
+
+/**
+ * Special case for glBlendFunc(GL_ZERO, GL_ONE).
+ * No-op means the framebuffer values remain unchanged.
+ * Any chanType ok.
+ */
+static void _BLENDAPI
+blend_noop(GLcontext *ctx, GLuint n, const GLubyte mask[],
+           GLvoid *src, const GLvoid *dst, GLenum chanType)
+{
+   GLint bytes;
+
+   ASSERT(ctx->Color.BlendEquationRGB == GL_FUNC_ADD);
+   ASSERT(ctx->Color.BlendEquationA == GL_FUNC_ADD);
+   ASSERT(ctx->Color.BlendSrcRGB == GL_ZERO);
+   ASSERT(ctx->Color.BlendDstRGB == GL_ONE);
+   (void) ctx;
+
+   /* just memcpy */
+   if (chanType == GL_UNSIGNED_BYTE)
+      bytes = 4 * n * sizeof(GLubyte);
+   else if (chanType == GL_UNSIGNED_SHORT)
+      bytes = 4 * n * sizeof(GLushort);
+   else
+      bytes = 4 * n * sizeof(GLfloat);
+
+   _mesa_memcpy(src, dst, bytes);
+}
+
+
+/**
+ * Special case for glBlendFunc(GL_ONE, GL_ZERO)
+ * Any chanType ok.
+ */
+static void _BLENDAPI
+blend_replace(GLcontext *ctx, GLuint n, const GLubyte mask[],
+              GLvoid *src, const GLvoid *dst, GLenum chanType)
+{
+   ASSERT(ctx->Color.BlendEquationRGB == GL_FUNC_ADD);
+   ASSERT(ctx->Color.BlendEquationA == GL_FUNC_ADD);
+   ASSERT(ctx->Color.BlendSrcRGB == GL_ONE);
+   ASSERT(ctx->Color.BlendDstRGB == GL_ZERO);
+   (void) ctx;
+   (void) n;
+   (void) mask;
+   (void) src;
+   (void) dst;
+}
+
+
+/**
+ * Common transparency blending mode:
+ * glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA).
+ */
+static void _BLENDAPI
+blend_transparency_ubyte(GLcontext *ctx, GLuint n, const GLubyte mask[],
+                         GLvoid *src, const GLvoid *dst, GLenum chanType)
+{
+   GLubyte (*rgba)[4] = (GLubyte (*)[4]) src;
+   const GLubyte (*dest)[4] = (const GLubyte (*)[4]) dst;
+   GLuint i;
+
+   ASSERT(ctx->Color.BlendEquationRGB == GL_FUNC_ADD);
+   ASSERT(ctx->Color.BlendEquationA == GL_FUNC_ADD);
+   ASSERT(ctx->Color.BlendSrcRGB == GL_SRC_ALPHA);
+   ASSERT(ctx->Color.BlendSrcA == GL_SRC_ALPHA);
+   ASSERT(ctx->Color.BlendDstRGB == GL_ONE_MINUS_SRC_ALPHA);
+   ASSERT(ctx->Color.BlendDstA == GL_ONE_MINUS_SRC_ALPHA);
+   ASSERT(chanType == GL_UNSIGNED_BYTE);
+
+   (void) ctx;
+
+   for (i = 0; i < n; i++) {
+      if (mask[i]) {
+         const GLint t = rgba[i][ACOMP];  /* t is in [0, 255] */
+         if (t == 0) {
+            /* 0% alpha */
+            COPY_4UBV(rgba[i], dest[i]);
+         }
+         else if (t != 255) {
+	    GLint divtemp;
+            const GLint r = DIV255((rgba[i][RCOMP] - dest[i][RCOMP]) * t) + dest[i][RCOMP];
+            const GLint g = DIV255((rgba[i][GCOMP] - dest[i][GCOMP]) * t) + dest[i][GCOMP];
+            const GLint b = DIV255((rgba[i][BCOMP] - dest[i][BCOMP]) * t) + dest[i][BCOMP];
+            const GLint a = DIV255((rgba[i][ACOMP] - dest[i][ACOMP]) * t) + dest[i][ACOMP]; 
+            ASSERT(r <= 255);
+            ASSERT(g <= 255);
+            ASSERT(b <= 255);
+            ASSERT(a <= 255);
+            rgba[i][RCOMP] = (GLubyte) r;
+            rgba[i][GCOMP] = (GLubyte) g;
+            rgba[i][BCOMP] = (GLubyte) b;
+            rgba[i][ACOMP] = (GLubyte) a;
+         }
+      }
+   }
+}
+
+
+static void _BLENDAPI
+blend_transparency_ushort(GLcontext *ctx, GLuint n, const GLubyte mask[],
+                          GLvoid *src, const GLvoid *dst, GLenum chanType)
+{
+   GLushort (*rgba)[4] = (GLushort (*)[4]) src;
+   const GLushort (*dest)[4] = (const GLushort (*)[4]) dst;
+   GLuint i;
+
+   ASSERT(ctx->Color.BlendEquationRGB == GL_FUNC_ADD);
+   ASSERT(ctx->Color.BlendEquationA == GL_FUNC_ADD);
+   ASSERT(ctx->Color.BlendSrcRGB == GL_SRC_ALPHA);
+   ASSERT(ctx->Color.BlendSrcA == GL_SRC_ALPHA);
+   ASSERT(ctx->Color.BlendDstRGB == GL_ONE_MINUS_SRC_ALPHA);
+   ASSERT(ctx->Color.BlendDstA == GL_ONE_MINUS_SRC_ALPHA);
+   ASSERT(chanType == GL_UNSIGNED_SHORT);
+
+   (void) ctx;
+
+   for (i = 0; i < n; i++) {
+      if (mask[i]) {
+         const GLint t = rgba[i][ACOMP];
+         if (t == 0) {
+            /* 0% alpha */
+            COPY_4V(rgba[i], dest[i]);
+         }
+         else if (t != 65535) {
+            const GLfloat tt = (GLfloat) t / 65535.0F;
+            GLushort r = (GLushort) ((rgba[i][RCOMP] - dest[i][RCOMP]) * tt + dest[i][RCOMP]);
+            GLushort g = (GLushort) ((rgba[i][GCOMP] - dest[i][GCOMP]) * tt + dest[i][GCOMP]);
+            GLushort b = (GLushort) ((rgba[i][BCOMP] - dest[i][BCOMP]) * tt + dest[i][BCOMP]);
+            GLushort a = (GLushort) ((rgba[i][ACOMP] - dest[i][ACOMP]) * tt + dest[i][ACOMP]);
+            ASSIGN_4V(rgba[i], r, g, b, a);
+         }
+      }
+   }
+}
+
+
+static void _BLENDAPI
+blend_transparency_float(GLcontext *ctx, GLuint n, const GLubyte mask[],
+                         GLvoid *src, const GLvoid *dst, GLenum chanType)
+{
+   GLfloat (*rgba)[4] = (GLfloat (*)[4]) src;
+   const GLfloat (*dest)[4] = (const GLfloat (*)[4]) dst;
+   GLuint i;
+
+   ASSERT(ctx->Color.BlendEquationRGB == GL_FUNC_ADD);
+   ASSERT(ctx->Color.BlendEquationA == GL_FUNC_ADD);
+   ASSERT(ctx->Color.BlendSrcRGB == GL_SRC_ALPHA);
+   ASSERT(ctx->Color.BlendSrcA == GL_SRC_ALPHA);
+   ASSERT(ctx->Color.BlendDstRGB == GL_ONE_MINUS_SRC_ALPHA);
+   ASSERT(ctx->Color.BlendDstA == GL_ONE_MINUS_SRC_ALPHA);
+   ASSERT(chanType == GL_FLOAT);
+
+   (void) ctx;
+
+   for (i = 0; i < n; i++) {
+      if (mask[i]) {
+         const GLfloat t = rgba[i][ACOMP];  /* t in [0, 1] */
+         if (t == 0.0F) {
+            /* 0% alpha */
+            COPY_4V(rgba[i], dest[i]);
+         }
+         else if (t != 1.0F) {
+            GLfloat r = (rgba[i][RCOMP] - dest[i][RCOMP]) * t + dest[i][RCOMP];
+            GLfloat g = (rgba[i][GCOMP] - dest[i][GCOMP]) * t + dest[i][GCOMP];
+            GLfloat b = (rgba[i][BCOMP] - dest[i][BCOMP]) * t + dest[i][BCOMP];
+            GLfloat a = (rgba[i][ACOMP] - dest[i][ACOMP]) * t + dest[i][ACOMP];
+            ASSIGN_4V(rgba[i], r, g, b, a);
+         }
+      }
+   }
+}
+
+
+
+/**
+ * Add src and dest: glBlendFunc(GL_ONE, GL_ONE).
+ * Any chanType ok.
+ */
+static void _BLENDAPI
+blend_add(GLcontext *ctx, GLuint n, const GLubyte mask[],
+          GLvoid *src, const GLvoid *dst, GLenum chanType)
+{
+   GLuint i;
+
+   ASSERT(ctx->Color.BlendEquationRGB == GL_FUNC_ADD);
+   ASSERT(ctx->Color.BlendEquationA == GL_FUNC_ADD);
+   ASSERT(ctx->Color.BlendSrcRGB == GL_ONE);
+   ASSERT(ctx->Color.BlendDstRGB == GL_ONE);
+   (void) ctx;
+
+   if (chanType == GL_UNSIGNED_BYTE) {
+      GLubyte (*rgba)[4] = (GLubyte (*)[4]) src;
+      const GLubyte (*dest)[4] = (const GLubyte (*)[4]) dst;
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            GLint r = rgba[i][RCOMP] + dest[i][RCOMP];
+            GLint g = rgba[i][GCOMP] + dest[i][GCOMP];
+            GLint b = rgba[i][BCOMP] + dest[i][BCOMP];
+            GLint a = rgba[i][ACOMP] + dest[i][ACOMP];
+            rgba[i][RCOMP] = (GLubyte) MIN2( r, 255 );
+            rgba[i][GCOMP] = (GLubyte) MIN2( g, 255 );
+            rgba[i][BCOMP] = (GLubyte) MIN2( b, 255 );
+            rgba[i][ACOMP] = (GLubyte) MIN2( a, 255 );
+         }
+      }
+   }
+   else if (chanType == GL_UNSIGNED_SHORT) {
+      GLushort (*rgba)[4] = (GLushort (*)[4]) src;
+      const GLushort (*dest)[4] = (const GLushort (*)[4]) dst;
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            GLint r = rgba[i][RCOMP] + dest[i][RCOMP];
+            GLint g = rgba[i][GCOMP] + dest[i][GCOMP];
+            GLint b = rgba[i][BCOMP] + dest[i][BCOMP];
+            GLint a = rgba[i][ACOMP] + dest[i][ACOMP];
+            rgba[i][RCOMP] = (GLshort) MIN2( r, 255 );
+            rgba[i][GCOMP] = (GLshort) MIN2( g, 255 );
+            rgba[i][BCOMP] = (GLshort) MIN2( b, 255 );
+            rgba[i][ACOMP] = (GLshort) MIN2( a, 255 );
+         }
+      }
+   }
+   else {
+      GLfloat (*rgba)[4] = (GLfloat (*)[4]) src;
+      const GLfloat (*dest)[4] = (const GLfloat (*)[4]) dst;
+      ASSERT(chanType == GL_FLOAT);
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            /* don't RGB clamp to max */
+            rgba[i][RCOMP] += dest[i][RCOMP];
+            rgba[i][GCOMP] += dest[i][GCOMP];
+            rgba[i][BCOMP] += dest[i][BCOMP];
+            rgba[i][ACOMP] += dest[i][ACOMP];
+         }
+      }
+   }
+}
+
+
+
+/**
+ * Blend min function.
+ * Any chanType ok.
+ */
+static void _BLENDAPI
+blend_min(GLcontext *ctx, GLuint n, const GLubyte mask[],
+          GLvoid *src, const GLvoid *dst, GLenum chanType)
+{
+   GLuint i;
+   ASSERT(ctx->Color.BlendEquationRGB == GL_MIN);
+   ASSERT(ctx->Color.BlendEquationA == GL_MIN);
+   (void) ctx;
+
+   if (chanType == GL_UNSIGNED_BYTE) {
+      GLubyte (*rgba)[4] = (GLubyte (*)[4]) src;
+      const GLubyte (*dest)[4] = (const GLubyte (*)[4]) dst;
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            rgba[i][RCOMP] = MIN2( rgba[i][RCOMP], dest[i][RCOMP] );
+            rgba[i][GCOMP] = MIN2( rgba[i][GCOMP], dest[i][GCOMP] );
+            rgba[i][BCOMP] = MIN2( rgba[i][BCOMP], dest[i][BCOMP] );
+            rgba[i][ACOMP] = MIN2( rgba[i][ACOMP], dest[i][ACOMP] );
+         }
+      }
+   }
+   else if (chanType == GL_UNSIGNED_SHORT) {
+      GLushort (*rgba)[4] = (GLushort (*)[4]) src;
+      const GLushort (*dest)[4] = (const GLushort (*)[4]) dst;
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            rgba[i][RCOMP] = MIN2( rgba[i][RCOMP], dest[i][RCOMP] );
+            rgba[i][GCOMP] = MIN2( rgba[i][GCOMP], dest[i][GCOMP] );
+            rgba[i][BCOMP] = MIN2( rgba[i][BCOMP], dest[i][BCOMP] );
+            rgba[i][ACOMP] = MIN2( rgba[i][ACOMP], dest[i][ACOMP] );
+         }
+      }
+   }
+   else {
+      GLfloat (*rgba)[4] = (GLfloat (*)[4]) src;
+      const GLfloat (*dest)[4] = (const GLfloat (*)[4]) dst;
+      ASSERT(chanType == GL_FLOAT);
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            rgba[i][RCOMP] = MIN2( rgba[i][RCOMP], dest[i][RCOMP] );
+            rgba[i][GCOMP] = MIN2( rgba[i][GCOMP], dest[i][GCOMP] );
+            rgba[i][BCOMP] = MIN2( rgba[i][BCOMP], dest[i][BCOMP] );
+            rgba[i][ACOMP] = MIN2( rgba[i][ACOMP], dest[i][ACOMP] );
+         }
+      }
+   }
+}
+
+
+/**
+ * Blend max function.
+ * Any chanType ok.
+ */
+static void _BLENDAPI
+blend_max(GLcontext *ctx, GLuint n, const GLubyte mask[],
+          GLvoid *src, const GLvoid *dst, GLenum chanType)
+{
+   GLuint i;
+   ASSERT(ctx->Color.BlendEquationRGB == GL_MAX);
+   ASSERT(ctx->Color.BlendEquationA == GL_MAX);
+   (void) ctx;
+
+   if (chanType == GL_UNSIGNED_BYTE) {
+      GLubyte (*rgba)[4] = (GLubyte (*)[4]) src;
+      const GLubyte (*dest)[4] = (const GLubyte (*)[4]) dst;
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            rgba[i][RCOMP] = MAX2( rgba[i][RCOMP], dest[i][RCOMP] );
+            rgba[i][GCOMP] = MAX2( rgba[i][GCOMP], dest[i][GCOMP] );
+            rgba[i][BCOMP] = MAX2( rgba[i][BCOMP], dest[i][BCOMP] );
+            rgba[i][ACOMP] = MAX2( rgba[i][ACOMP], dest[i][ACOMP] );
+         }
+      }
+   }
+   else if (chanType == GL_UNSIGNED_SHORT) {
+      GLushort (*rgba)[4] = (GLushort (*)[4]) src;
+      const GLushort (*dest)[4] = (const GLushort (*)[4]) dst;
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            rgba[i][RCOMP] = MAX2( rgba[i][RCOMP], dest[i][RCOMP] );
+            rgba[i][GCOMP] = MAX2( rgba[i][GCOMP], dest[i][GCOMP] );
+            rgba[i][BCOMP] = MAX2( rgba[i][BCOMP], dest[i][BCOMP] );
+            rgba[i][ACOMP] = MAX2( rgba[i][ACOMP], dest[i][ACOMP] );
+         }
+      }
+   }
+   else {
+      GLfloat (*rgba)[4] = (GLfloat (*)[4]) src;
+      const GLfloat (*dest)[4] = (const GLfloat (*)[4]) dst;
+      ASSERT(chanType == GL_FLOAT);
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            rgba[i][RCOMP] = MAX2( rgba[i][RCOMP], dest[i][RCOMP] );
+            rgba[i][GCOMP] = MAX2( rgba[i][GCOMP], dest[i][GCOMP] );
+            rgba[i][BCOMP] = MAX2( rgba[i][BCOMP], dest[i][BCOMP] );
+            rgba[i][ACOMP] = MAX2( rgba[i][ACOMP], dest[i][ACOMP] );
+         }
+      }
+   }
+}
+
+
+
+/**
+ * Modulate:  result = src * dest
+ * Any chanType ok.
+ */
+static void _BLENDAPI
+blend_modulate(GLcontext *ctx, GLuint n, const GLubyte mask[],
+               GLvoid *src, const GLvoid *dst, GLenum chanType)
+{
+   GLuint i;
+   (void) ctx;
+
+   if (chanType == GL_UNSIGNED_BYTE) {
+      GLubyte (*rgba)[4] = (GLubyte (*)[4]) src;
+      const GLubyte (*dest)[4] = (const GLubyte (*)[4]) dst;
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+	    GLint divtemp;
+            rgba[i][RCOMP] = DIV255(rgba[i][RCOMP] * dest[i][RCOMP]);
+            rgba[i][GCOMP] = DIV255(rgba[i][GCOMP] * dest[i][GCOMP]);
+            rgba[i][BCOMP] = DIV255(rgba[i][BCOMP] * dest[i][BCOMP]);
+            rgba[i][ACOMP] = DIV255(rgba[i][ACOMP] * dest[i][ACOMP]);
+         }
+      }
+   }
+   else if (chanType == GL_UNSIGNED_SHORT) {
+      GLushort (*rgba)[4] = (GLushort (*)[4]) src;
+      const GLushort (*dest)[4] = (const GLushort (*)[4]) dst;
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            rgba[i][RCOMP] = (rgba[i][RCOMP] * dest[i][RCOMP] + 65535) >> 16;
+            rgba[i][GCOMP] = (rgba[i][GCOMP] * dest[i][GCOMP] + 65535) >> 16;
+            rgba[i][BCOMP] = (rgba[i][BCOMP] * dest[i][BCOMP] + 65535) >> 16;
+            rgba[i][ACOMP] = (rgba[i][ACOMP] * dest[i][ACOMP] + 65535) >> 16;
+         }
+      }
+   }
+   else {
+      GLfloat (*rgba)[4] = (GLfloat (*)[4]) src;
+      const GLfloat (*dest)[4] = (const GLfloat (*)[4]) dst;
+      ASSERT(chanType == GL_FLOAT);
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            rgba[i][RCOMP] = rgba[i][RCOMP] * dest[i][RCOMP];
+            rgba[i][GCOMP] = rgba[i][GCOMP] * dest[i][GCOMP];
+            rgba[i][BCOMP] = rgba[i][BCOMP] * dest[i][BCOMP];
+            rgba[i][ACOMP] = rgba[i][ACOMP] * dest[i][ACOMP];
+         }
+      }
+   }
+}
+
+
+/**
+ * Do any blending operation, using floating point.
+ * \param n  number of pixels
+ * \param mask  fragment writemask array
+ * \param rgba  array of incoming (and modified) pixels
+ * \param dest  array of pixels from the dest color buffer
+ */
+static void
+blend_general_float(GLcontext *ctx, GLuint n, const GLubyte mask[],
+                    GLfloat rgba[][4], GLfloat dest[][4],
+                    GLenum chanType)
+{
+   GLuint i;
+
+   for (i = 0; i < n; i++) {
+      if (mask[i]) {
+         /* Incoming/source Color */
+         const GLfloat Rs = rgba[i][RCOMP];
+         const GLfloat Gs = rgba[i][GCOMP];
+         const GLfloat Bs = rgba[i][BCOMP];
+         const GLfloat As = rgba[i][ACOMP];
+
+         /* Frame buffer/dest color */
+         const GLfloat Rd = dest[i][RCOMP];
+         const GLfloat Gd = dest[i][GCOMP];
+         const GLfloat Bd = dest[i][BCOMP];
+         const GLfloat Ad = dest[i][ACOMP];
+
+         GLfloat sR, sG, sB, sA;  /* Source factor */
+         GLfloat dR, dG, dB, dA;  /* Dest factor */
+         GLfloat r, g, b, a;      /* result color */
+
+         /* XXX for the case of constant blend terms we could init
+          * the sX and dX variables just once before the loop.
+          */
+
+         /* Source RGB factor */
+         switch (ctx->Color.BlendSrcRGB) {
+            case GL_ZERO:
+               sR = sG = sB = 0.0F;
+               break;
+            case GL_ONE:
+               sR = sG = sB = 1.0F;
+               break;
+            case GL_DST_COLOR:
+               sR = Rd;
+               sG = Gd;
+               sB = Bd;
+               break;
+            case GL_ONE_MINUS_DST_COLOR:
+               sR = 1.0F - Rd;
+               sG = 1.0F - Gd;
+               sB = 1.0F - Bd;
+               break;
+            case GL_SRC_ALPHA:
+               sR = sG = sB = As;
+               break;
+            case GL_ONE_MINUS_SRC_ALPHA:
+               sR = sG = sB = 1.0F - As;
+               break;
+            case GL_DST_ALPHA:
+               sR = sG = sB = Ad;
+               break;
+            case GL_ONE_MINUS_DST_ALPHA:
+               sR = sG = sB = 1.0F - Ad;
+               break;
+            case GL_SRC_ALPHA_SATURATE:
+               if (As < 1.0F - Ad) {
+                  sR = sG = sB = As;
+               }
+               else {
+                  sR = sG = sB = 1.0F - Ad;
+               }
+               break;
+            case GL_CONSTANT_COLOR:
+               sR = ctx->Color.BlendColor[0];
+               sG = ctx->Color.BlendColor[1];
+               sB = ctx->Color.BlendColor[2];
+               break;
+            case GL_ONE_MINUS_CONSTANT_COLOR:
+               sR = 1.0F - ctx->Color.BlendColor[0];
+               sG = 1.0F - ctx->Color.BlendColor[1];
+               sB = 1.0F - ctx->Color.BlendColor[2];
+               break;
+            case GL_CONSTANT_ALPHA:
+               sR = sG = sB = ctx->Color.BlendColor[3];
+               break;
+            case GL_ONE_MINUS_CONSTANT_ALPHA:
+               sR = sG = sB = 1.0F - ctx->Color.BlendColor[3];
+               break;
+            case GL_SRC_COLOR:
+               sR = Rs;
+               sG = Gs;
+               sB = Bs;
+               break;
+            case GL_ONE_MINUS_SRC_COLOR:
+               sR = 1.0F - Rs;
+               sG = 1.0F - Gs;
+               sB = 1.0F - Bs;
+               break;
+            default:
+               /* this should never happen */
+               _mesa_problem(ctx, "Bad blend source RGB factor in blend_general_float");
+               return;
+         }
+
+         /* Source Alpha factor */
+         switch (ctx->Color.BlendSrcA) {
+            case GL_ZERO:
+               sA = 0.0F;
+               break;
+            case GL_ONE:
+               sA = 1.0F;
+               break;
+            case GL_DST_COLOR:
+               sA = Ad;
+               break;
+            case GL_ONE_MINUS_DST_COLOR:
+               sA = 1.0F - Ad;
+               break;
+            case GL_SRC_ALPHA:
+               sA = As;
+               break;
+            case GL_ONE_MINUS_SRC_ALPHA:
+               sA = 1.0F - As;
+               break;
+            case GL_DST_ALPHA:
+               sA = Ad;
+               break;
+            case GL_ONE_MINUS_DST_ALPHA:
+               sA = 1.0F - Ad;
+               break;
+            case GL_SRC_ALPHA_SATURATE:
+               sA = 1.0;
+               break;
+            case GL_CONSTANT_COLOR:
+               sA = ctx->Color.BlendColor[3];
+               break;
+            case GL_ONE_MINUS_CONSTANT_COLOR:
+               sA = 1.0F - ctx->Color.BlendColor[3];
+               break;
+            case GL_CONSTANT_ALPHA:
+               sA = ctx->Color.BlendColor[3];
+               break;
+            case GL_ONE_MINUS_CONSTANT_ALPHA:
+               sA = 1.0F - ctx->Color.BlendColor[3];
+               break;
+            case GL_SRC_COLOR:
+               sA = As;
+               break;
+            case GL_ONE_MINUS_SRC_COLOR:
+               sA = 1.0F - As;
+               break;
+            default:
+               /* this should never happen */
+               sA = 0.0F;
+               _mesa_problem(ctx, "Bad blend source A factor in blend_general_float");
+               return;
+         }
+
+         /* Dest RGB factor */
+         switch (ctx->Color.BlendDstRGB) {
+            case GL_ZERO:
+               dR = dG = dB = 0.0F;
+               break;
+            case GL_ONE:
+               dR = dG = dB = 1.0F;
+               break;
+            case GL_SRC_COLOR:
+               dR = Rs;
+               dG = Gs;
+               dB = Bs;
+               break;
+            case GL_ONE_MINUS_SRC_COLOR:
+               dR = 1.0F - Rs;
+               dG = 1.0F - Gs;
+               dB = 1.0F - Bs;
+               break;
+            case GL_SRC_ALPHA:
+               dR = dG = dB = As;
+               break;
+            case GL_ONE_MINUS_SRC_ALPHA:
+               dR = dG = dB = 1.0F - As;
+               break;
+            case GL_DST_ALPHA:
+               dR = dG = dB = Ad;
+               break;
+            case GL_ONE_MINUS_DST_ALPHA:
+               dR = dG = dB = 1.0F - Ad;
+               break;
+            case GL_CONSTANT_COLOR:
+               dR = ctx->Color.BlendColor[0];
+               dG = ctx->Color.BlendColor[1];
+               dB = ctx->Color.BlendColor[2];
+               break;
+            case GL_ONE_MINUS_CONSTANT_COLOR:
+               dR = 1.0F - ctx->Color.BlendColor[0];
+               dG = 1.0F - ctx->Color.BlendColor[1];
+               dB = 1.0F - ctx->Color.BlendColor[2];
+               break;
+            case GL_CONSTANT_ALPHA:
+               dR = dG = dB = ctx->Color.BlendColor[3];
+               break;
+            case GL_ONE_MINUS_CONSTANT_ALPHA:
+               dR = dG = dB = 1.0F - ctx->Color.BlendColor[3];
+               break;
+            case GL_DST_COLOR:
+               dR = Rd;
+               dG = Gd;
+               dB = Bd;
+               break;
+            case GL_ONE_MINUS_DST_COLOR:
+               dR = 1.0F - Rd;
+               dG = 1.0F - Gd;
+               dB = 1.0F - Bd;
+               break;
+            default:
+               /* this should never happen */
+               dR = dG = dB = 0.0F;
+               _mesa_problem(ctx, "Bad blend dest RGB factor in blend_general_float");
+               return;
+         }
+
+         /* Dest Alpha factor */
+         switch (ctx->Color.BlendDstA) {
+            case GL_ZERO:
+               dA = 0.0F;
+               break;
+            case GL_ONE:
+               dA = 1.0F;
+               break;
+            case GL_SRC_COLOR:
+               dA = As;
+               break;
+            case GL_ONE_MINUS_SRC_COLOR:
+               dA = 1.0F - As;
+               break;
+            case GL_SRC_ALPHA:
+               dA = As;
+               break;
+            case GL_ONE_MINUS_SRC_ALPHA:
+               dA = 1.0F - As;
+               break;
+            case GL_DST_ALPHA:
+               dA = Ad;
+               break;
+            case GL_ONE_MINUS_DST_ALPHA:
+               dA = 1.0F - Ad;
+               break;
+            case GL_CONSTANT_COLOR:
+               dA = ctx->Color.BlendColor[3];
+               break;
+            case GL_ONE_MINUS_CONSTANT_COLOR:
+               dA = 1.0F - ctx->Color.BlendColor[3];
+               break;
+            case GL_CONSTANT_ALPHA:
+               dA = ctx->Color.BlendColor[3];
+               break;
+            case GL_ONE_MINUS_CONSTANT_ALPHA:
+               dA = 1.0F - ctx->Color.BlendColor[3];
+               break;
+            case GL_DST_COLOR:
+               dA = Ad;
+               break;
+            case GL_ONE_MINUS_DST_COLOR:
+               dA = 1.0F - Ad;
+               break;
+            default:
+               /* this should never happen */
+               dA = 0.0F;
+               _mesa_problem(ctx, "Bad blend dest A factor in blend_general_float");
+               return;
+         }
+
+         /* compute the blended RGB */
+         switch (ctx->Color.BlendEquationRGB) {
+         case GL_FUNC_ADD:
+            r = Rs * sR + Rd * dR;
+            g = Gs * sG + Gd * dG;
+            b = Bs * sB + Bd * dB;
+            a = As * sA + Ad * dA;
+            break;
+         case GL_FUNC_SUBTRACT:
+            r = Rs * sR - Rd * dR;
+            g = Gs * sG - Gd * dG;
+            b = Bs * sB - Bd * dB;
+            a = As * sA - Ad * dA;
+            break;
+         case GL_FUNC_REVERSE_SUBTRACT:
+            r = Rd * dR - Rs * sR;
+            g = Gd * dG - Gs * sG;
+            b = Bd * dB - Bs * sB;
+            a = Ad * dA - As * sA;
+            break;
+         case GL_MIN:
+	    r = MIN2( Rd, Rs );
+	    g = MIN2( Gd, Gs );
+	    b = MIN2( Bd, Bs );
+            break;
+         case GL_MAX:
+	    r = MAX2( Rd, Rs );
+	    g = MAX2( Gd, Gs );
+	    b = MAX2( Bd, Bs );
+            break;
+	 default:
+            /* should never get here */
+            r = g = b = 0.0F;  /* silence uninitialized var warning */
+            _mesa_problem(ctx, "unexpected BlendEquation in blend_general()");
+            return;
+         }
+
+         /* compute the blended alpha */
+         switch (ctx->Color.BlendEquationA) {
+         case GL_FUNC_ADD:
+            a = As * sA + Ad * dA;
+            break;
+         case GL_FUNC_SUBTRACT:
+            a = As * sA - Ad * dA;
+            break;
+         case GL_FUNC_REVERSE_SUBTRACT:
+            a = Ad * dA - As * sA;
+            break;
+         case GL_MIN:
+	    a = MIN2( Ad, As );
+            break;
+         case GL_MAX:
+	    a = MAX2( Ad, As );
+            break;
+         default:
+            /* should never get here */
+            a = 0.0F;  /* silence uninitialized var warning */
+            _mesa_problem(ctx, "unexpected BlendEquation in blend_general()");
+            return;
+         }
+
+         /* final clamping */
+#if 0
+         rgba[i][RCOMP] = MAX2( r, 0.0F );
+         rgba[i][GCOMP] = MAX2( g, 0.0F );
+         rgba[i][BCOMP] = MAX2( b, 0.0F );
+         rgba[i][ACOMP] = CLAMP( a, 0.0F, 1.0F );
+#else
+         ASSIGN_4V(rgba[i], r, g, b, a);
+#endif
+      }
+   }
+}
+
+
+/**
+ * Do any blending operation, any chanType.
+ */
+static void
+blend_general(GLcontext *ctx, GLuint n, const GLubyte mask[],
+              void *src, const void *dst, GLenum chanType)
+{
+   GLfloat rgbaF[MAX_WIDTH][4], destF[MAX_WIDTH][4];
+
+   if (chanType == GL_UNSIGNED_BYTE) {
+      GLubyte (*rgba)[4] = (GLubyte (*)[4]) src;
+      const GLubyte (*dest)[4] = (const GLubyte (*)[4]) dst;
+      GLuint i;
+      /* convert ubytes to floats */
+      for (i = 0; i < n; i++) {
+         if (mask[i]) {
+            rgbaF[i][RCOMP] = UBYTE_TO_FLOAT(rgba[i][RCOMP]);
+            rgbaF[i][GCOMP] = UBYTE_TO_FLOAT(rgba[i][GCOMP]);
+            rgbaF[i][BCOMP] = UBYTE_TO_FLOAT(rgba[i][BCOMP]);
+            rgbaF[i][ACOMP] = UBYTE_TO_FLOAT(rgba[i][ACOMP]);
+            destF[i][RCOMP] = UBYTE_TO_FLOAT(dest[i][RCOMP]);
+            destF[i][GCOMP] = UBYTE_TO_FLOAT(dest[i][GCOMP]);
+            destF[i][BCOMP] = UBYTE_TO_FLOAT(dest[i][BCOMP]);
+            destF[i][ACOMP] = UBYTE_TO_FLOAT(dest[i][ACOMP]);
+         }
+      }
+      /* do blend */
+      blend_general_float(ctx, n, mask, rgbaF, destF, chanType);
+      /* convert back to ubytes */
+      for (i = 0; i < n; i++) {
+         if (mask[i]) {
+            UNCLAMPED_FLOAT_TO_UBYTE(rgba[i][RCOMP], rgbaF[i][RCOMP]);
+            UNCLAMPED_FLOAT_TO_UBYTE(rgba[i][GCOMP], rgbaF[i][GCOMP]);
+            UNCLAMPED_FLOAT_TO_UBYTE(rgba[i][BCOMP], rgbaF[i][BCOMP]);
+            UNCLAMPED_FLOAT_TO_UBYTE(rgba[i][ACOMP], rgbaF[i][ACOMP]);
+         }
+      }
+   }
+   else if (chanType == GL_UNSIGNED_SHORT) {
+      GLushort (*rgba)[4] = (GLushort (*)[4]) src;
+      const GLushort (*dest)[4] = (const GLushort (*)[4]) dst;
+      GLuint i;
+      /* convert ushorts to floats */
+      for (i = 0; i < n; i++) {
+         if (mask[i]) {
+            rgbaF[i][RCOMP] = USHORT_TO_FLOAT(rgba[i][RCOMP]);
+            rgbaF[i][GCOMP] = USHORT_TO_FLOAT(rgba[i][GCOMP]);
+            rgbaF[i][BCOMP] = USHORT_TO_FLOAT(rgba[i][BCOMP]);
+            rgbaF[i][ACOMP] = USHORT_TO_FLOAT(rgba[i][ACOMP]);
+            destF[i][RCOMP] = USHORT_TO_FLOAT(dest[i][RCOMP]);
+            destF[i][GCOMP] = USHORT_TO_FLOAT(dest[i][GCOMP]);
+            destF[i][BCOMP] = USHORT_TO_FLOAT(dest[i][BCOMP]);
+            destF[i][ACOMP] = USHORT_TO_FLOAT(dest[i][ACOMP]);
+         }
+      }
+      /* do blend */
+      blend_general_float(ctx, n, mask, rgbaF, destF, chanType);
+      /* convert back to ushorts */
+      for (i = 0; i < n; i++) {
+         if (mask[i]) {
+            UNCLAMPED_FLOAT_TO_USHORT(rgba[i][RCOMP], rgbaF[i][RCOMP]);
+            UNCLAMPED_FLOAT_TO_USHORT(rgba[i][GCOMP], rgbaF[i][GCOMP]);
+            UNCLAMPED_FLOAT_TO_USHORT(rgba[i][BCOMP], rgbaF[i][BCOMP]);
+            UNCLAMPED_FLOAT_TO_USHORT(rgba[i][ACOMP], rgbaF[i][ACOMP]);
+         }
+      }
+   }
+   else {
+      blend_general_float(ctx, n, mask, (GLfloat (*)[4]) src,
+                          (GLfloat (*)[4]) dst, chanType);
+   }
+}
+
+
+
+/**
+ * Analyze current blending parameters to pick fastest blending function.
+ * Result: the ctx->Color.BlendFunc pointer is updated.
+ */
+void
+_swrast_choose_blend_func(GLcontext *ctx, GLenum chanType)
+{
+   SWcontext *swrast = SWRAST_CONTEXT(ctx);
+   const GLenum eq = ctx->Color.BlendEquationRGB;
+   const GLenum srcRGB = ctx->Color.BlendSrcRGB;
+   const GLenum dstRGB = ctx->Color.BlendDstRGB;
+   const GLenum srcA = ctx->Color.BlendSrcA;
+   const GLenum dstA = ctx->Color.BlendDstA;
+
+   if (ctx->Color.BlendEquationRGB != ctx->Color.BlendEquationA) {
+      swrast->BlendFunc = blend_general;
+   }
+   else if (eq == GL_MIN) {
+      /* Note: GL_MIN ignores the blending weight factors */
+#if defined(USE_MMX_ASM)
+      if (cpu_has_mmx && chanType == GL_UNSIGNED_BYTE) {
+         swrast->BlendFunc = _mesa_mmx_blend_min;
+      }
+      else
+#endif
+         swrast->BlendFunc = blend_min;
+   }
+   else if (eq == GL_MAX) {
+      /* Note: GL_MAX ignores the blending weight factors */
+#if defined(USE_MMX_ASM)
+      if (cpu_has_mmx && chanType == GL_UNSIGNED_BYTE) {
+         swrast->BlendFunc = _mesa_mmx_blend_max;
+      }
+      else
+#endif
+         swrast->BlendFunc = blend_max;
+   }
+   else if (srcRGB != srcA || dstRGB != dstA) {
+      swrast->BlendFunc = blend_general;
+   }
+   else if (eq == GL_FUNC_ADD && srcRGB == GL_SRC_ALPHA
+            && dstRGB == GL_ONE_MINUS_SRC_ALPHA) {
+#if defined(USE_MMX_ASM)
+      if (cpu_has_mmx && chanType == GL_UNSIGNED_BYTE) {
+         swrast->BlendFunc = _mesa_mmx_blend_transparency;
+      }
+      else
+#endif
+      {
+         if (chanType == GL_UNSIGNED_BYTE)
+            swrast->BlendFunc = blend_transparency_ubyte;
+         else if (chanType == GL_UNSIGNED_SHORT)
+            swrast->BlendFunc = blend_transparency_ushort;
+         else
+            swrast->BlendFunc = blend_transparency_float;
+      }
+   }
+   else if (eq == GL_FUNC_ADD && srcRGB == GL_ONE && dstRGB == GL_ONE) {
+#if defined(USE_MMX_ASM)
+      if (cpu_has_mmx && chanType == GL_UNSIGNED_BYTE) {
+         swrast->BlendFunc = _mesa_mmx_blend_add;
+      }
+      else
+#endif
+         swrast->BlendFunc = blend_add;
+   }
+   else if (((eq == GL_FUNC_ADD || eq == GL_FUNC_REVERSE_SUBTRACT)
+	     && (srcRGB == GL_ZERO && dstRGB == GL_SRC_COLOR))
+	    ||
+	    ((eq == GL_FUNC_ADD || eq == GL_FUNC_SUBTRACT)
+	     && (srcRGB == GL_DST_COLOR && dstRGB == GL_ZERO))) {
+#if defined(USE_MMX_ASM)
+      if (cpu_has_mmx && chanType == GL_UNSIGNED_BYTE) {
+         swrast->BlendFunc = _mesa_mmx_blend_modulate;
+      }
+      else
+#endif
+         swrast->BlendFunc = blend_modulate;
+   }
+   else if (eq == GL_FUNC_ADD && srcRGB == GL_ZERO && dstRGB == GL_ONE) {
+      swrast->BlendFunc = blend_noop;
+   }
+   else if (eq == GL_FUNC_ADD && srcRGB == GL_ONE && dstRGB == GL_ZERO) {
+      swrast->BlendFunc = blend_replace;
+   }
+   else {
+      swrast->BlendFunc = blend_general;
+   }
+}
+
+
+
+/**
+ * Apply the blending operator to a span of pixels.
+ * We can handle horizontal runs of pixels (spans) or arrays of x/y
+ * pixel coordinates.
+ */
+void
+_swrast_blend_span(GLcontext *ctx, struct gl_renderbuffer *rb, SWspan *span)
+{
+   SWcontext *swrast = SWRAST_CONTEXT(ctx);
+   void *rbPixels;
+
+   ASSERT(span->end <= MAX_WIDTH);
+   ASSERT(span->arrayMask & SPAN_RGBA);
+   ASSERT(rb->DataType == span->array->ChanType);
+   ASSERT(!ctx->Color._LogicOpEnabled);
+
+   rbPixels = _swrast_get_dest_rgba(ctx, rb, span);
+
+   swrast->BlendFunc(ctx, span->end, span->array->mask,
+                     span->array->rgba, rbPixels, span->array->ChanType);
+}