Moved software rasterizer functionality to new directory.

1 files changed, 765 insertions, 0 deletions

diff --git a/src/mesa/swrast/s_readpix.c b/src/mesa/swrast/s_readpix.c
new file mode 100644
index 00000000000..74a4d682661
--- /dev/null
+++ b/src/mesa/swrast/s_readpix.c
@@ -0,0 +1,765 @@
+/* $Id: s_readpix.c,v 1.1 2000/10/31 18:00:04 keithw Exp $ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version:  3.5
+ * 
+ * Copyright (C) 1999-2000  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.
+ */
+
+
+#include "glheader.h"
+#include "colormac.h"
+#include "convolve.h"
+#include "context.h"
+#include "feedback.h"
+#include "image.h"
+#include "macros.h"
+#include "mem.h"
+#include "pixel.h"
+
+#include "s_alphabuf.h"
+#include "s_depth.h"
+#include "s_span.h"
+#include "s_stencil.h"
+
+
+
+/*
+ * Read a block of color index pixels.
+ */
+static void read_index_pixels( GLcontext *ctx,
+                               GLint x, GLint y,
+			       GLsizei width, GLsizei height,
+			       GLenum type, GLvoid *pixels,
+                               const struct gl_pixelstore_attrib *packing )
+{
+   GLint i, j, readWidth;
+
+   /* error checking */
+   if (ctx->Visual.RGBAflag) {
+      gl_error( ctx, GL_INVALID_OPERATION, "glReadPixels" );
+      return;
+   }
+
+   ASSERT(ctx->Driver.SetReadBuffer);
+   (*ctx->Driver.SetReadBuffer)(ctx, ctx->ReadBuffer, ctx->Pixel.DriverReadBuffer);
+
+   readWidth = (width > MAX_WIDTH) ? MAX_WIDTH : width;
+
+   /* process image row by row */
+   for (j=0;j<height;j++,y++) {
+      GLuint index[MAX_WIDTH];
+      GLvoid *dest;
+
+      (*ctx->Driver.ReadCI32Span)( ctx, readWidth, x, y, index );
+
+      if (ctx->Pixel.IndexShift!=0 || ctx->Pixel.IndexOffset!=0) {
+         _mesa_shift_and_offset_ci( ctx, readWidth, index);
+      }
+
+      if (ctx->Pixel.MapColorFlag) {
+         _mesa_map_ci(ctx, readWidth, index);
+      }
+
+      dest = _mesa_image_address(packing, pixels,
+                         width, height, GL_COLOR_INDEX, type, 0, j, 0);
+
+      switch (type) {
+	 case GL_UNSIGNED_BYTE:
+	    {
+               GLubyte *dst = (GLubyte *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  *dst++ = (GLubyte) index[i];
+	       }
+	    }
+	    break;
+	 case GL_BYTE:
+	    {
+               GLbyte *dst = (GLbyte *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  dst[i] = (GLbyte) index[i];
+	       }
+	    }
+	    break;
+	 case GL_UNSIGNED_SHORT:
+	    {
+               GLushort *dst = (GLushort *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  dst[i] = (GLushort) index[i];
+	       }
+	       if (packing->SwapBytes) {
+		  _mesa_swap2( (GLushort *) dst, readWidth );
+	       }
+	    }
+	    break;
+	 case GL_SHORT:
+	    {
+               GLshort *dst = (GLshort *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  dst[i] = (GLshort) index[i];
+	       }
+	       if (packing->SwapBytes) {
+		  _mesa_swap2( (GLushort *) dst, readWidth );
+	       }
+	    }
+	    break;
+	 case GL_UNSIGNED_INT:
+	    {
+               GLuint *dst = (GLuint *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  dst[i] = (GLuint) index[i];
+	       }
+	       if (packing->SwapBytes) {
+		  _mesa_swap4( (GLuint *) dst, readWidth );
+	       }
+	    }
+	    break;
+	 case GL_INT:
+	    {
+               GLint *dst = (GLint *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  dst[i] = (GLint) index[i];
+	       }
+	       if (packing->SwapBytes) {
+		  _mesa_swap4( (GLuint *) dst, readWidth );
+	       }
+	    }
+	    break;
+	 case GL_FLOAT:
+	    {
+               GLfloat *dst = (GLfloat *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  dst[i] = (GLfloat) index[i];
+	       }
+	       if (packing->SwapBytes) {
+		  _mesa_swap4( (GLuint *) dst, readWidth );
+	       }
+	    }
+	    break;
+         default:
+            gl_error( ctx, GL_INVALID_ENUM, "glReadPixels(type)" );
+            j = height + 1; /* exit loop */
+      }
+   }
+
+   (*ctx->Driver.SetReadBuffer)(ctx, ctx->DrawBuffer, ctx->Color.DriverDrawBuffer);
+}
+
+
+
+static void read_depth_pixels( GLcontext *ctx,
+                               GLint x, GLint y,
+			       GLsizei width, GLsizei height,
+			       GLenum type, GLvoid *pixels,
+                               const struct gl_pixelstore_attrib *packing )
+{
+   GLint i, j, readWidth;
+   GLboolean bias_or_scale;
+
+   /* Error checking */
+   if (ctx->Visual.DepthBits <= 0) {
+      /* No depth buffer */
+      gl_error( ctx, GL_INVALID_OPERATION, "glReadPixels" );
+      return;
+   }
+
+   readWidth = (width > MAX_WIDTH) ? MAX_WIDTH : width;
+
+   if (type != GL_BYTE &&
+       type != GL_UNSIGNED_BYTE &&
+       type != GL_SHORT &&
+       type != GL_UNSIGNED_SHORT &&
+       type != GL_INT &&
+       type != GL_UNSIGNED_INT &&
+       type != GL_FLOAT) {
+      gl_error( ctx, GL_INVALID_OPERATION, "glReadPixels(depth type)");
+      return;
+   }
+
+   bias_or_scale = ctx->Pixel.DepthBias!=0.0 || ctx->Pixel.DepthScale!=1.0;
+
+   if (type==GL_UNSIGNED_SHORT && ctx->Visual.DepthBits == 16
+       && !bias_or_scale && !packing->SwapBytes) {
+      /* Special case: directly read 16-bit unsigned depth values. */
+      for (j=0;j<height;j++,y++) {
+         GLdepth depth[MAX_WIDTH];
+         GLushort *dst = (GLushort*) _mesa_image_address( packing, pixels,
+                         width, height, GL_DEPTH_COMPONENT, type, 0, j, 0 );
+         GLint i;
+         _mesa_read_depth_span(ctx, width, x, y, depth);
+         for (i = 0; i < width; i++)
+            dst[i] = depth[i];
+      }
+   }
+   else if (type==GL_UNSIGNED_INT && ctx->Visual.DepthBits == 32
+            && !bias_or_scale && !packing->SwapBytes) {
+      /* Special case: directly read 32-bit unsigned depth values. */
+      for (j=0;j<height;j++,y++) {
+         GLdepth *dst = (GLdepth *) _mesa_image_address( packing, pixels,
+                         width, height, GL_DEPTH_COMPONENT, type, 0, j, 0 );
+         _mesa_read_depth_span(ctx, width, x, y, dst);
+      }
+   }
+   else {
+      /* General case (slower) */
+      for (j=0;j<height;j++,y++) {
+         GLfloat depth[MAX_WIDTH];
+         GLvoid *dest;
+
+         _mesa_read_depth_span_float(ctx, readWidth, x, y, depth);
+
+         if (bias_or_scale) {
+            for (i=0;i<readWidth;i++) {
+               GLfloat d;
+               d = depth[i] * ctx->Pixel.DepthScale + ctx->Pixel.DepthBias;
+               depth[i] = CLAMP( d, 0.0F, 1.0F );
+            }
+         }
+
+         dest = _mesa_image_address(packing, pixels,
+                         width, height, GL_DEPTH_COMPONENT, type, 0, j, 0);
+
+         switch (type) {
+            case GL_UNSIGNED_BYTE:
+               {
+                  GLubyte *dst = (GLubyte *) dest;
+                  for (i=0;i<readWidth;i++) {
+                     dst[i] = FLOAT_TO_UBYTE( depth[i] );
+                  }
+               }
+               break;
+            case GL_BYTE:
+               {
+                  GLbyte *dst = (GLbyte *) dest;
+                  for (i=0;i<readWidth;i++) {
+                     dst[i] = FLOAT_TO_BYTE( depth[i] );
+                  }
+               }
+               break;
+            case GL_UNSIGNED_SHORT:
+               {
+                  GLushort *dst = (GLushort *) dest;
+                  for (i=0;i<readWidth;i++) {
+                     dst[i] = FLOAT_TO_USHORT( depth[i] );
+                  }
+                  if (packing->SwapBytes) {
+                     _mesa_swap2( (GLushort *) dst, readWidth );
+                  }
+               }
+               break;
+            case GL_SHORT:
+               {
+                  GLshort *dst = (GLshort *) dest;
+                  for (i=0;i<readWidth;i++) {
+                     dst[i] = FLOAT_TO_SHORT( depth[i] );
+                  }
+                  if (packing->SwapBytes) {
+                     _mesa_swap2( (GLushort *) dst, readWidth );
+                  }
+               }
+               break;
+            case GL_UNSIGNED_INT:
+               {
+                  GLuint *dst = (GLuint *) dest;
+                  for (i=0;i<readWidth;i++) {
+                     dst[i] = FLOAT_TO_UINT( depth[i] );
+                  }
+                  if (packing->SwapBytes) {
+                     _mesa_swap4( (GLuint *) dst, readWidth );
+                  }
+               }
+               break;
+            case GL_INT:
+               {
+                  GLint *dst = (GLint *) dest;
+                  for (i=0;i<readWidth;i++) {
+                     dst[i] = FLOAT_TO_INT( depth[i] );
+                  }
+                  if (packing->SwapBytes) {
+                     _mesa_swap4( (GLuint *) dst, readWidth );
+                  }
+               }
+               break;
+            case GL_FLOAT:
+               {
+                  GLfloat *dst = (GLfloat *) dest;
+                  for (i=0;i<readWidth;i++) {
+                     dst[i] = depth[i];
+                  }
+                  if (packing->SwapBytes) {
+                     _mesa_swap4( (GLuint *) dst, readWidth );
+                  }
+               }
+               break;
+            default:
+               gl_error( ctx, GL_INVALID_ENUM, "glReadPixels(type)" );
+         }
+      }
+   }
+}
+
+
+
+static void read_stencil_pixels( GLcontext *ctx,
+                                 GLint x, GLint y,
+				 GLsizei width, GLsizei height,
+				 GLenum type, GLvoid *pixels,
+                                 const struct gl_pixelstore_attrib *packing )
+{
+   GLboolean shift_or_offset;
+   GLint i, j, readWidth;
+
+   if (type != GL_BYTE &&
+       type != GL_UNSIGNED_BYTE &&
+       type != GL_SHORT &&
+       type != GL_UNSIGNED_SHORT &&
+       type != GL_INT &&
+       type != GL_UNSIGNED_INT &&
+       type != GL_FLOAT &&
+       type != GL_BITMAP) {
+      gl_error( ctx, GL_INVALID_OPERATION, "glReadPixels(stencil type)");
+      return;
+   }
+
+   readWidth = (width > MAX_WIDTH) ? MAX_WIDTH : width;
+
+   if (ctx->Visual.StencilBits<=0) {
+      /* No stencil buffer */
+      gl_error( ctx, GL_INVALID_OPERATION, "glReadPixels" );
+      return;
+   }
+
+   shift_or_offset = ctx->Pixel.IndexShift!=0 || ctx->Pixel.IndexOffset!=0;
+
+   /* process image row by row */
+   for (j=0;j<height;j++,y++) {
+      GLvoid *dest;
+      GLstencil stencil[MAX_WIDTH];
+
+      _mesa_read_stencil_span( ctx, readWidth, x, y, stencil );
+
+      if (shift_or_offset) {
+         _mesa_shift_and_offset_stencil( ctx, readWidth, stencil );
+      }
+
+      if (ctx->Pixel.MapStencilFlag) {
+         _mesa_map_stencil( ctx, readWidth, stencil );
+      }
+
+      dest = _mesa_image_address( packing, pixels,
+                          width, height, GL_STENCIL_INDEX, type, 0, j, 0 );
+
+      switch (type) {
+	 case GL_UNSIGNED_BYTE:
+            if (sizeof(GLstencil) == 8) {
+               MEMCPY( dest, stencil, readWidth );
+            }
+            else {
+               GLubyte *dst = (GLubyte *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  dst[i] = (GLubyte) stencil[i];
+	       }
+            }
+	    break;
+	 case GL_BYTE:
+            if (sizeof(GLstencil) == 8) {
+               MEMCPY( dest, stencil, readWidth );
+            }
+            else {
+               GLbyte *dst = (GLbyte *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  dst[i] = (GLbyte) stencil[i];
+	       }
+            }
+	    break;
+	 case GL_UNSIGNED_SHORT:
+	    {
+               GLushort *dst = (GLushort *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  dst[i] = (GLushort) stencil[i];
+	       }
+	       if (packing->SwapBytes) {
+		  _mesa_swap2( (GLushort *) dst, readWidth );
+	       }
+	    }
+	    break;
+	 case GL_SHORT:
+	    {
+               GLshort *dst = (GLshort *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  dst[i] = (GLshort) stencil[i];
+	       }
+	       if (packing->SwapBytes) {
+		  _mesa_swap2( (GLushort *) dst, readWidth );
+	       }
+	    }
+	    break;
+	 case GL_UNSIGNED_INT:
+	    {
+               GLuint *dst = (GLuint *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  dst[i] = (GLuint) stencil[i];
+	       }
+	       if (packing->SwapBytes) {
+		  _mesa_swap4( (GLuint *) dst, readWidth );
+	       }
+	    }
+	    break;
+	 case GL_INT:
+	    {
+               GLint *dst = (GLint *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  *dst++ = (GLint) stencil[i];
+	       }
+	       if (packing->SwapBytes) {
+		  _mesa_swap4( (GLuint *) dst, readWidth );
+	       }
+	    }
+	    break;
+	 case GL_FLOAT:
+	    {
+               GLfloat *dst = (GLfloat *) dest;
+	       for (i=0;i<readWidth;i++) {
+		  dst[i] = (GLfloat) stencil[i];
+	       }
+	       if (packing->SwapBytes) {
+		  _mesa_swap4( (GLuint *) dst, readWidth );
+	       }
+	    }
+	    break;
+         case GL_BITMAP:
+            if (packing->LsbFirst) {
+               GLubyte *dst = (GLubyte*) dest;
+               GLint shift = 0;
+               for (i = 0; i < readWidth; i++) {
+                  if (shift == 0)
+                     *dst = 0;
+                  *dst |= ((stencil != 0) << shift);
+                  shift++;
+                  if (shift == 8) {
+                     shift = 0;
+                     dst++;
+                  }
+               }
+            }
+            else {
+               GLubyte *dst = (GLubyte*) dest;
+               GLint shift = 7;
+               for (i = 0; i < readWidth; i++) {
+                  if (shift == 7)
+                     *dst = 0;
+                  *dst |= ((stencil != 0) << shift);
+                  shift--;
+                  if (shift < 0) {
+                     shift = 7;
+                     dst++;
+                  }
+               }
+            }
+            break;
+         default:
+            gl_error( ctx, GL_INVALID_ENUM, "glReadPixels(type)" );
+      }
+   }
+}
+
+
+
+/*
+ * Optimized glReadPixels for particular pixel formats:
+ *   GL_UNSIGNED_BYTE, GL_RGBA
+ * when pixel scaling, biasing and mapping are disabled.
+ */
+static GLboolean
+read_fast_rgba_pixels( GLcontext *ctx,
+                       GLint x, GLint y,
+                       GLsizei width, GLsizei height,
+                       GLenum format, GLenum type,
+                       GLvoid *pixels,
+                       const struct gl_pixelstore_attrib *packing )
+{
+   /* can't do scale, bias, mapping, etc */
+   if (ctx->ImageTransferState)
+       return GL_FALSE;
+
+   /* can't do fancy pixel packing */
+   if (packing->Alignment != 1 || packing->SwapBytes || packing->LsbFirst)
+      return GL_FALSE;
+
+   {
+      GLint srcX = x;
+      GLint srcY = y;
+      GLint readWidth = width;           /* actual width read */
+      GLint readHeight = height;         /* actual height read */
+      GLint skipPixels = packing->SkipPixels;
+      GLint skipRows = packing->SkipRows;
+      GLint rowLength;
+
+      if (packing->RowLength > 0)
+         rowLength = packing->RowLength;
+      else
+         rowLength = width;
+
+      /* horizontal clipping */
+      if (srcX < ctx->ReadBuffer->Xmin) {
+         skipPixels += (ctx->ReadBuffer->Xmin - srcX);
+         readWidth  -= (ctx->ReadBuffer->Xmin - srcX);
+         srcX = ctx->ReadBuffer->Xmin;
+      }
+      if (srcX + readWidth > ctx->ReadBuffer->Xmax)
+         readWidth -= (srcX + readWidth - ctx->ReadBuffer->Xmax);
+      if (readWidth <= 0)
+         return GL_TRUE;
+
+      /* vertical clipping */
+      if (srcY < ctx->ReadBuffer->Ymin) {
+         skipRows   += (ctx->ReadBuffer->Ymin - srcY);
+         readHeight -= (ctx->ReadBuffer->Ymin - srcY);
+         srcY = ctx->ReadBuffer->Ymin;
+      }
+      if (srcY + readHeight > ctx->ReadBuffer->Ymax)
+         readHeight -= (srcY + readHeight - ctx->ReadBuffer->Ymax);
+      if (readHeight <= 0)
+         return GL_TRUE;
+
+      /*
+       * Ready to read!
+       * The window region at (destX, destY) of size (readWidth, readHeight)
+       * will be read back.
+       * We'll write pixel data to buffer pointed to by "pixels" but we'll
+       * skip "skipRows" rows and skip "skipPixels" pixels/row.
+       */
+#if CHAN_BITS == 8
+      if (format == GL_RGBA && type == GL_UNSIGNED_BYTE) {
+#elif CHAN_BITS == 16
+      if (format == GL_RGBA && type == GL_UNSIGNED_SHORT) {
+#else
+      if (0) {
+#endif
+         GLchan *dest = (GLchan *) pixels
+                         + (skipRows * rowLength + skipPixels) * 4;
+         GLint row;
+         for (row=0; row<readHeight; row++) {
+            (*ctx->Driver.ReadRGBASpan)(ctx, readWidth, srcX, srcY,
+                                        (GLchan (*)[4]) dest);
+            if (ctx->DrawBuffer->UseSoftwareAlphaBuffers) {
+               _mesa_read_alpha_span(ctx, readWidth, srcX, srcY,
+                                     (GLchan (*)[4]) dest);
+            }
+            dest += rowLength * 4;
+            srcY++;
+         }
+         return GL_TRUE;
+      }
+      else {
+         /* can't do this format/type combination */
+         return GL_FALSE;
+      }
+   }
+}
+
+
+
+/*
+ * Read R, G, B, A, RGB, L, or LA pixels.
+ */
+static void read_rgba_pixels( GLcontext *ctx,
+                              GLint x, GLint y,
+                              GLsizei width, GLsizei height,
+                              GLenum format, GLenum type, GLvoid *pixels,
+                              const struct gl_pixelstore_attrib *packing )
+{
+   GLint readWidth;
+
+   (*ctx->Driver.SetReadBuffer)(ctx, ctx->ReadBuffer, ctx->Pixel.DriverReadBuffer);
+
+   /* Try optimized path first */
+   if (read_fast_rgba_pixels( ctx, x, y, width, height,
+                              format, type, pixels, packing )) {
+
+      (*ctx->Driver.SetReadBuffer)(ctx, ctx->DrawBuffer, ctx->Color.DriverDrawBuffer);
+      return; /* done! */
+   }
+
+   readWidth = (width > MAX_WIDTH) ? MAX_WIDTH : width;
+
+   /* do error checking on pixel type, format was already checked by caller */
+   switch (type) {
+      case GL_UNSIGNED_BYTE:
+      case GL_BYTE:
+      case GL_UNSIGNED_SHORT:
+      case GL_SHORT:
+      case GL_UNSIGNED_INT:
+      case GL_INT:
+      case GL_FLOAT:
+      case GL_UNSIGNED_BYTE_3_3_2:
+      case GL_UNSIGNED_BYTE_2_3_3_REV:
+      case GL_UNSIGNED_SHORT_5_6_5:
+      case GL_UNSIGNED_SHORT_5_6_5_REV:
+      case GL_UNSIGNED_SHORT_4_4_4_4:
+      case GL_UNSIGNED_SHORT_4_4_4_4_REV:
+      case GL_UNSIGNED_SHORT_5_5_5_1:
+      case GL_UNSIGNED_SHORT_1_5_5_5_REV:
+      case GL_UNSIGNED_INT_8_8_8_8:
+      case GL_UNSIGNED_INT_8_8_8_8_REV:
+      case GL_UNSIGNED_INT_10_10_10_2:
+      case GL_UNSIGNED_INT_2_10_10_10_REV:
+         /* valid pixel type */
+         break;
+      default:
+         gl_error( ctx, GL_INVALID_ENUM, "glReadPixels(type)" );
+         return;
+   }
+
+   if (!_mesa_is_legal_format_and_type(format, type) ||
+       format == GL_INTENSITY) {
+      gl_error(ctx, GL_INVALID_OPERATION, "glReadPixels(format or type)");
+      return;
+   }
+
+   if (ctx->Pixel.Convolution2DEnabled || ctx->Pixel.Separable2DEnabled) {
+      const GLuint transferOps = ctx->ImageTransferState;
+      GLfloat *dest, *src, *tmpImage, *convImage;
+      GLint row;
+
+      tmpImage = (GLfloat *) MALLOC(width * height * 4 * sizeof(GLfloat));
+      if (!tmpImage) {
+         gl_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels");
+         return;
+      }
+      convImage = (GLfloat *) MALLOC(width * height * 4 * sizeof(GLfloat));
+      if (!convImage) {
+         FREE(tmpImage);
+         gl_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels");
+         return;
+      }
+
+      /* read full RGBA, FLOAT image */
+      dest = tmpImage;
+      for (row = 0; row < height; row++, y++) {
+         GLchan rgba[MAX_WIDTH][4];
+         if (ctx->Visual.RGBAflag) {
+            gl_read_rgba_span(ctx, ctx->ReadBuffer, readWidth, x, y, rgba);
+         }
+         else {
+            GLuint index[MAX_WIDTH];
+            (*ctx->Driver.ReadCI32Span)(ctx, readWidth, x, y, index);
+            if (ctx->Pixel.IndexShift != 0 || ctx->Pixel.IndexOffset !=0 ) {
+               _mesa_map_ci(ctx, readWidth, index);
+            }
+            _mesa_map_ci_to_rgba_chan(ctx, readWidth, index, rgba);
+         }
+         _mesa_pack_rgba_span(ctx, readWidth, (const GLchan (*)[4]) rgba,
+                              GL_RGBA, GL_FLOAT, dest, &_mesa_native_packing,
+                              transferOps & IMAGE_PRE_CONVOLUTION_BITS);
+         dest += width * 4;
+      }
+
+      /* do convolution */
+      if (ctx->Pixel.Convolution2DEnabled) {
+         _mesa_convolve_2d_image(ctx, &readWidth, &height, tmpImage, convImage);
+      }
+      else {
+         ASSERT(ctx->Pixel.Separable2DEnabled);
+         _mesa_convolve_sep_image(ctx, &readWidth, &height, tmpImage, convImage);
+      }
+      FREE(tmpImage);
+
+      /* finish transfer ops and pack the resulting image */
+      src = convImage;
+      for (row = 0; row < height; row++) {
+         GLvoid *dest;
+         dest = _mesa_image_address(packing, pixels, width, height,
+                                    format, type, 0, row, 0);
+         _mesa_pack_float_rgba_span(ctx, readWidth,
+                                    (const GLfloat (*)[4]) src,
+                                    format, type, dest, packing,
+                                    transferOps & IMAGE_POST_CONVOLUTION_BITS);
+         src += readWidth * 4;
+      }
+   }
+   else {
+      /* no convolution */
+      GLint row;
+      for (row = 0; row < height; row++, y++) {
+         GLchan rgba[MAX_WIDTH][4];
+         GLvoid *dst;
+         if (ctx->Visual.RGBAflag) {
+            gl_read_rgba_span(ctx, ctx->ReadBuffer, readWidth, x, y, rgba);
+         }
+         else {
+            GLuint index[MAX_WIDTH];
+            (*ctx->Driver.ReadCI32Span)(ctx, readWidth, x, y, index);
+            if (ctx->Pixel.IndexShift != 0 || ctx->Pixel.IndexOffset != 0) {
+               _mesa_map_ci(ctx, readWidth, index);
+            }
+            _mesa_map_ci_to_rgba_chan(ctx, readWidth, index, rgba);
+         }
+         dst = _mesa_image_address(packing, pixels, width, height,
+                                   format, type, 0, row, 0);
+         _mesa_pack_rgba_span(ctx, readWidth, (const GLchan (*)[4]) rgba,
+                              format, type, dst, packing,
+                              ctx->ImageTransferState);
+      }
+   }
+
+   (*ctx->Driver.SetReadBuffer)(ctx, ctx->DrawBuffer, ctx->Color.DriverDrawBuffer);
+}
+
+
+
+void
+_swrast_ReadPixels( GLcontext *ctx,
+		    GLint x, GLint y, GLsizei width, GLsizei height,
+		    GLenum format, GLenum type, 
+		    const struct gl_pixelstore_attrib *pack,
+		    GLvoid *pixels )
+{
+   (void) pack;
+
+   switch (format) {
+      case GL_COLOR_INDEX:
+         read_index_pixels(ctx, x, y, width, height, type, pixels, &ctx->Pack);
+	 break;
+      case GL_STENCIL_INDEX:
+	 read_stencil_pixels(ctx, x,y, width,height, type, pixels, &ctx->Pack);
+         break;
+      case GL_DEPTH_COMPONENT:
+	 read_depth_pixels(ctx, x, y, width, height, type, pixels, &ctx->Pack);
+	 break;
+      case GL_RED:
+      case GL_GREEN:
+      case GL_BLUE:
+      case GL_ALPHA:
+      case GL_RGB:
+      case GL_LUMINANCE:
+      case GL_LUMINANCE_ALPHA:
+      case GL_RGBA:
+      case GL_BGR:
+      case GL_BGRA:
+      case GL_ABGR_EXT:
+         read_rgba_pixels(ctx, x, y, width, height,
+                          format, type, pixels, &ctx->Pack);
+	 break;
+      default:
+	 gl_error( ctx, GL_INVALID_ENUM, "glReadPixels(format)" );
+   }
+}