src/mesa/main/teximage.c

/* $Id: teximage.c,v 1.66 2000/12/08 18:09:33 brianp 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.
 */


#ifdef PC_HEADER
#include "all.h"
#else
#include "glheader.h"
#include "context.h"
#include "convolve.h"
#include "image.h"
#include "macros.h"
#include "mem.h"
#include "mmath.h"
#include "state.h"
#include "teximage.h"
#include "texstate.h"
#include "mtypes.h"
#include "swrast/s_span.h" /* XXX SWRAST hack */
#endif


/*
 * NOTES:
 *
 * Mesa's native texture datatype is GLchan.  Native formats are
 * GL_ALPHA, GL_LUMINANCE, GL_LUMANCE_ALPHA, GL_INTENSITY, GL_RGB, GL_RGBA,
 * and GL_COLOR_INDEX.
 * Device drivers are free to implement any internal format they want.
 */


#ifdef DEBUG
static void PrintTexture(const struct gl_texture_image *img)
{
  int i, j, c;
  GLchan *data = img->Data;

  if (!data) {
     printf("No texture data\n");
     return;
  }

  switch (img->Format) {
     case GL_ALPHA:
     case GL_LUMINANCE:
     case GL_INTENSITY:
     case GL_COLOR_INDEX:
        c = 1;
        break;
     case GL_LUMINANCE_ALPHA:
        c = 2;
        break;
     case GL_RGB:
        c = 3;
        break;
     case GL_RGBA:
        c = 4;
        break;
     default:
        gl_problem(NULL, "error in PrintTexture\n");
        return;
  }


  for (i = 0; i < img->Height; i++) {
    for (j = 0; j < img->Width; j++) {
      if (c==1)
        printf("%02x  ", data[0]);
      else if (c==2)
        printf("%02x%02x  ", data[0], data[1]);
      else if (c==3)
        printf("%02x%02x%02x  ", data[0], data[1], data[2]);
      else if (c==4)
        printf("%02x%02x%02x%02x  ", data[0], data[1], data[2], data[3]);
      data += c;
    }
    printf("\n");
  }
}
#endif



/*
 * Compute log base 2 of n.
 * If n isn't an exact power of two return -1.
 * If n<0 return -1.
 */
static int
logbase2( int n )
{
   GLint i = 1;
   GLint log2 = 0;

   if (n<0) {
      return -1;
   }

   while ( n > i ) {
      i *= 2;
      log2++;
   }
   if (i != n) {
      return -1;
   }
   else {
      return log2;
   }
}



/*
 * Given an internal texture format enum or 1, 2, 3, 4 return the
 * corresponding _base_ internal format:  GL_ALPHA, GL_LUMINANCE,
 * GL_LUMANCE_ALPHA, GL_INTENSITY, GL_RGB, or GL_RGBA.
 * Return -1 if invalid enum.
 */
GLint
_mesa_base_tex_format( GLcontext *ctx, GLint format )
{
  /*
   * Ask the driver for the base format, if it doesn't
   * know, it will return -1;
   */
   if (ctx->Driver.BaseCompressedTexFormat) {
      GLint ifmt = (*ctx->Driver.BaseCompressedTexFormat)(ctx, format);
      if (ifmt >= 0) {
         return ifmt;
      }
   }
   switch (format) {
      case GL_ALPHA:
      case GL_ALPHA4:
      case GL_ALPHA8:
      case GL_ALPHA12:
      case GL_ALPHA16:
         return GL_ALPHA;
      case 1:
      case GL_LUMINANCE:
      case GL_LUMINANCE4:
      case GL_LUMINANCE8:
      case GL_LUMINANCE12:
      case GL_LUMINANCE16:
         return GL_LUMINANCE;
      case 2:
      case GL_LUMINANCE_ALPHA:
      case GL_LUMINANCE4_ALPHA4:
      case GL_LUMINANCE6_ALPHA2:
      case GL_LUMINANCE8_ALPHA8:
      case GL_LUMINANCE12_ALPHA4:
      case GL_LUMINANCE12_ALPHA12:
      case GL_LUMINANCE16_ALPHA16:
         return GL_LUMINANCE_ALPHA;
      case GL_INTENSITY:
      case GL_INTENSITY4:
      case GL_INTENSITY8:
      case GL_INTENSITY12:
      case GL_INTENSITY16:
         return GL_INTENSITY;
      case 3:
      case GL_RGB:
      case GL_R3_G3_B2:
      case GL_RGB4:
      case GL_RGB5:
      case GL_RGB8:
      case GL_RGB10:
      case GL_RGB12:
      case GL_RGB16:
         return GL_RGB;
      case 4:
      case GL_RGBA:
      case GL_RGBA2:
      case GL_RGBA4:
      case GL_RGB5_A1:
      case GL_RGBA8:
      case GL_RGB10_A2:
      case GL_RGBA12:
      case GL_RGBA16:
         return GL_RGBA;
      case GL_COLOR_INDEX:
      case GL_COLOR_INDEX1_EXT:
      case GL_COLOR_INDEX2_EXT:
      case GL_COLOR_INDEX4_EXT:
      case GL_COLOR_INDEX8_EXT:
      case GL_COLOR_INDEX12_EXT:
      case GL_COLOR_INDEX16_EXT:
         return GL_COLOR_INDEX;
      default:
         return -1;  /* error */
   }
}



/*
 * Given an internal texture format enum or 1, 2, 3, 4 return the
 * corresponding _base_ internal format:  GL_ALPHA, GL_LUMINANCE,
 * GL_LUMANCE_ALPHA, GL_INTENSITY, GL_RGB, or GL_RGBA.  Return the
 * number of components for the format.  Return -1 if invalid enum.
 */
static GLint
components_in_intformat( GLint format )
{
   switch (format) {
      case GL_ALPHA:
      case GL_ALPHA4:
      case GL_ALPHA8:
      case GL_ALPHA12:
      case GL_ALPHA16:
         return 1;
      case 1:
      case GL_LUMINANCE:
      case GL_LUMINANCE4:
      case GL_LUMINANCE8:
      case GL_LUMINANCE12:
      case GL_LUMINANCE16:
         return 1;
      case 2:
      case GL_LUMINANCE_ALPHA:
      case GL_LUMINANCE4_ALPHA4:
      case GL_LUMINANCE6_ALPHA2:
      case GL_LUMINANCE8_ALPHA8:
      case GL_LUMINANCE12_ALPHA4:
      case GL_LUMINANCE12_ALPHA12:
      case GL_LUMINANCE16_ALPHA16:
         return 2;
      case GL_INTENSITY:
      case GL_INTENSITY4:
      case GL_INTENSITY8:
      case GL_INTENSITY12:
      case GL_INTENSITY16:
         return 1;
      case 3:
      case GL_RGB:
      case GL_R3_G3_B2:
      case GL_RGB4:
      case GL_RGB5:
      case GL_RGB8:
      case GL_RGB10:
      case GL_RGB12:
      case GL_RGB16:
         return 3;
      case 4:
      case GL_RGBA:
      case GL_RGBA2:
      case GL_RGBA4:
      case GL_RGB5_A1:
      case GL_RGBA8:
      case GL_RGB10_A2:
      case GL_RGBA12:
      case GL_RGBA16:
         return 4;
      case GL_COLOR_INDEX:
      case GL_COLOR_INDEX1_EXT:
      case GL_COLOR_INDEX2_EXT:
      case GL_COLOR_INDEX4_EXT:
      case GL_COLOR_INDEX8_EXT:
      case GL_COLOR_INDEX12_EXT:
      case GL_COLOR_INDEX16_EXT:
         return 1;
      default:
         return -1;  /* error */
   }
}


/*
 * Return GL_TRUE if internalFormat is a compressed format, return GL_FALSE
 * otherwise.
 */
static GLboolean
is_compressed_format(GLcontext *ctx, GLenum internalFormat)
{
    if (ctx->Driver.IsCompressedFormat) {
        return (*ctx->Driver.IsCompressedFormat)(ctx, internalFormat);
    }
    return GL_FALSE;
}



/*
 * Examine the texImage->Format field and set the Red, Green, Blue, etc
 * texel component sizes to default values.
 * These fields are set only here by core Mesa but device drivers may
 * overwritting these fields to indicate true texel resolution.
 */
static void
set_teximage_component_sizes( struct gl_texture_image *texImage )
{
   switch (texImage->Format) {
      case GL_ALPHA:
         texImage->RedBits = 0;
         texImage->GreenBits = 0;
         texImage->BlueBits = 0;
         texImage->AlphaBits = 8;
         texImage->IntensityBits = 0;
         texImage->LuminanceBits = 0;
         texImage->IndexBits = 0;
         break;
      case GL_LUMINANCE:
         texImage->RedBits = 0;
         texImage->GreenBits = 0;
         texImage->BlueBits = 0;
         texImage->AlphaBits = 0;
         texImage->IntensityBits = 0;
         texImage->LuminanceBits = 8;
         texImage->IndexBits = 0;
         break;
      case GL_LUMINANCE_ALPHA:
         texImage->RedBits = 0;
         texImage->GreenBits = 0;
         texImage->BlueBits = 0;
         texImage->AlphaBits = 8;
         texImage->IntensityBits = 0;
         texImage->LuminanceBits = 8;
         texImage->IndexBits = 0;
         break;
      case GL_INTENSITY:
         texImage->RedBits = 0;
         texImage->GreenBits = 0;
         texImage->BlueBits = 0;
         texImage->AlphaBits = 0;
         texImage->IntensityBits = 8;
         texImage->LuminanceBits = 0;
         texImage->IndexBits = 0;
         break;
      case GL_RED:
         texImage->RedBits = 8;
         texImage->GreenBits = 0;
         texImage->BlueBits = 0;
         texImage->AlphaBits = 0;
         texImage->IntensityBits = 0;
         texImage->LuminanceBits = 0;
         texImage->IndexBits = 0;
         break;
      case GL_GREEN:
         texImage->RedBits = 0;
         texImage->GreenBits = 8;
         texImage->BlueBits = 0;
         texImage->AlphaBits = 0;
         texImage->IntensityBits = 0;
         texImage->LuminanceBits = 0;
         texImage->IndexBits = 0;
         break;
      case GL_BLUE:
         texImage->RedBits = 0;
         texImage->GreenBits = 0;
         texImage->BlueBits = 8;
         texImage->AlphaBits = 0;
         texImage->IntensityBits = 0;
         texImage->LuminanceBits = 0;
         texImage->IndexBits = 0;
         break;
      case GL_RGB:
      case GL_BGR:
         texImage->RedBits = 8;
         texImage->GreenBits = 8;
         texImage->BlueBits = 8;
         texImage->AlphaBits = 0;
         texImage->IntensityBits = 0;
         texImage->LuminanceBits = 0;
         texImage->IndexBits = 0;
         break;
      case GL_RGBA:
      case GL_BGRA:
      case GL_ABGR_EXT:
         texImage->RedBits = 8;
         texImage->GreenBits = 8;
         texImage->BlueBits = 8;
         texImage->AlphaBits = 8;
         texImage->IntensityBits = 0;
         texImage->LuminanceBits = 0;
         texImage->IndexBits = 0;
         break;
      case GL_COLOR_INDEX:
         texImage->RedBits = 0;
         texImage->GreenBits = 0;
         texImage->BlueBits = 0;
         texImage->AlphaBits = 0;
         texImage->IntensityBits = 0;
         texImage->LuminanceBits = 0;
         texImage->IndexBits = 8;
         break;
      default:
         gl_problem(NULL, "unexpected format in set_teximage_component_sizes");
   }
}


static void
set_tex_image(struct gl_texture_object *tObj,
              GLenum target, GLint level,
              struct gl_texture_image *texImage)
{
   ASSERT(tObj);
   ASSERT(texImage);
   switch (target) {
      case GL_TEXTURE_2D:
         tObj->Image[level] = texImage;
         return;
      case GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB:
         tObj->Image[level] = texImage;
         return;
      case GL_TEXTURE_CUBE_MAP_NEGATIVE_X_ARB:
         tObj->NegX[level] = texImage;
         return;
      case GL_TEXTURE_CUBE_MAP_POSITIVE_Y_ARB:
         tObj->PosY[level] = texImage;
         return;
      case GL_TEXTURE_CUBE_MAP_NEGATIVE_Y_ARB:
         tObj->NegY[level] = texImage;
         return;
      case GL_TEXTURE_CUBE_MAP_POSITIVE_Z_ARB:
         tObj->PosZ[level] = texImage;
         return;
      case GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB:
         tObj->NegZ[level] = texImage;
         return;
      default:
         gl_problem(NULL, "bad target in set_tex_image()");
         return;
   }
}


/*
 * Return new gl_texture_image struct with all fields initialized to zero.
 */
struct gl_texture_image *
_mesa_alloc_texture_image( void )
{
   return CALLOC_STRUCT(gl_texture_image);
}



/*
 * Initialize most fields of a gl_texture_image struct.
 */
static void
init_texture_image( GLcontext *ctx,
                    struct gl_texture_image *img,
                    GLsizei width, GLsizei height, GLsizei depth,
                    GLint border, GLenum internalFormat )
{
   ASSERT(img);
   ASSERT(!img->Data);
   img->Format = (GLenum) _mesa_base_tex_format(ctx, internalFormat);
   set_teximage_component_sizes( img );
   img->IntFormat = (GLenum) internalFormat;
   img->Border = border;
   img->Width = width;
   img->Height = height;
   img->Depth = depth;
   img->WidthLog2 = logbase2(width - 2 * border);
   if (height == 1)  /* 1-D texture */
      img->HeightLog2 = 0;
   else
      img->HeightLog2 = logbase2(height - 2 * border);
   if (depth == 1)   /* 2-D texture */
      img->DepthLog2 = 0;
   else
      img->DepthLog2 = logbase2(depth - 2 * border);
   img->Width2 = 1 << img->WidthLog2;
   img->Height2 = 1 << img->HeightLog2;
   img->Depth2 = 1 << img->DepthLog2;
   img->MaxLog2 = MAX2(img->WidthLog2, img->HeightLog2);
   img->IsCompressed = is_compressed_format(ctx, internalFormat);
}



void
_mesa_free_texture_image( struct gl_texture_image *teximage )
{
   if (teximage->Data) {
      FREE( teximage->Data );
      teximage->Data = NULL;
   }
   FREE( teximage );
}



/*
 * Return number of bytes of storage needed to store a compressed texture
 * image.  Only the driver knows for sure.  If the driver can't help us,
 * we must return 0.
 */
GLuint
_mesa_compressed_image_size(GLcontext *ctx,
                            GLenum internalFormat,
                            GLint numDimensions,
                            GLint width,
                            GLint height,
                            GLint depth)
{
   if (ctx->Driver.CompressedImageSize) {
      return (*ctx->Driver.CompressedImageSize)(ctx, internalFormat,
                                                numDimensions,
                                                width, height, depth);
   }
   else {
      /* Shouldn't this be an internal error of some sort? */
      return 0;
   }
}



/*
 * Given a texture unit and a texture target, return the corresponding
 * texture object.
 */
struct gl_texture_object *
_mesa_select_tex_object(GLcontext *ctx, const struct gl_texture_unit *texUnit,
                        GLenum target)
{
   switch (target) {
      case GL_TEXTURE_1D:
         return texUnit->Current1D;
      case GL_PROXY_TEXTURE_1D:
         return ctx->Texture.Proxy1D;
      case GL_TEXTURE_2D:
         return texUnit->Current2D;
      case GL_PROXY_TEXTURE_2D:
         return ctx->Texture.Proxy2D;
      case GL_TEXTURE_3D:
         return texUnit->Current3D;
      case GL_PROXY_TEXTURE_3D:
         return ctx->Texture.Proxy3D;
      case GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB:
      case GL_TEXTURE_CUBE_MAP_NEGATIVE_X_ARB:
      case GL_TEXTURE_CUBE_MAP_POSITIVE_Y_ARB:
      case GL_TEXTURE_CUBE_MAP_NEGATIVE_Y_ARB:
      case GL_TEXTURE_CUBE_MAP_POSITIVE_Z_ARB:
      case GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB:
         return ctx->Extensions.ARB_texture_cube_map
                ? texUnit->CurrentCubeMap : NULL;
      case GL_PROXY_TEXTURE_CUBE_MAP_ARB:
         return ctx->Extensions.ARB_texture_cube_map
                ? ctx->Texture.ProxyCubeMap : NULL;
      default:
         gl_problem(NULL, "bad target in _mesa_select_tex_object()");
         return NULL;
   }
}


/*
 * Return the texture image struct which corresponds to target and level
 * for the given texture unit.
 */
struct gl_texture_image *
_mesa_select_tex_image(GLcontext *ctx, const struct gl_texture_unit *texUnit,
                       GLenum target, GLint level)
{
   ASSERT(texUnit);
   switch (target) {
      case GL_TEXTURE_1D:
         return texUnit->Current1D->Image[level];
      case GL_PROXY_TEXTURE_1D:
         return ctx->Texture.Proxy1D->Image[level];
      case GL_TEXTURE_2D:
         return texUnit->Current2D->Image[level];
      case GL_PROXY_TEXTURE_2D:
         return ctx->Texture.Proxy2D->Image[level];
      case GL_TEXTURE_3D:
         return texUnit->Current3D->Image[level];
      case GL_PROXY_TEXTURE_3D:
         return ctx->Texture.Proxy3D->Image[level];
      case GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB:
         if (ctx->Extensions.ARB_texture_cube_map)
            return texUnit->CurrentCubeMap->Image[level];
         else
            return NULL;
      case GL_TEXTURE_CUBE_MAP_NEGATIVE_X_ARB:
         if (ctx->Extensions.ARB_texture_cube_map)
            return texUnit->CurrentCubeMap->NegX[level];
         else
            return NULL;
      case GL_TEXTURE_CUBE_MAP_POSITIVE_Y_ARB:
         if (ctx->Extensions.ARB_texture_cube_map)
            return texUnit->CurrentCubeMap->PosY[level];
         else
            return NULL;
      case GL_TEXTURE_CUBE_MAP_NEGATIVE_Y_ARB:
         if (ctx->Extensions.ARB_texture_cube_map)
            return texUnit->CurrentCubeMap->NegY[level];
         else
            return NULL;
      case GL_TEXTURE_CUBE_MAP_POSITIVE_Z_ARB:
         if (ctx->Extensions.ARB_texture_cube_map)
            return texUnit->CurrentCubeMap->PosZ[level];
         else
            return NULL;
      case GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB:
         if (ctx->Extensions.ARB_texture_cube_map)
            return texUnit->CurrentCubeMap->NegZ[level];
         else
            return NULL;
      case GL_PROXY_TEXTURE_CUBE_MAP_ARB:
         if (ctx->Extensions.ARB_texture_cube_map)
            return ctx->Texture.ProxyCubeMap->Image[level];
         else
            return NULL;
      default:
         gl_problem(ctx, "bad target in _mesa_select_tex_image()");
         return NULL;
   }
}



/*
 * Calling glTexImage and related functions when convolution is enabled
 * with GL_REDUCE border mode causes some complications.
 * The incoming image must be extra large so that the post-convolution
 * image size is reduced to a power of two size (plus 2 * border).
 * This function adjusts a texture width and height accordingly if
 * convolution with GL_REDUCE is enabled.
 */
static void
adjust_texture_size_for_convolution(const GLcontext *ctx, GLuint dimensions,
                                    GLsizei *width, GLsizei *height)
{
   if (ctx->Pixel.Convolution1DEnabled
       && dimensions == 1
       && ctx->Pixel.ConvolutionBorderMode[0] == GL_REDUCE) {
      *width = *width - (MAX2(ctx->Convolution1D.Width, 1) - 1);
   }
   else if (ctx->Pixel.Convolution2DEnabled
            && dimensions > 1
            && ctx->Pixel.ConvolutionBorderMode[1] == GL_REDUCE) {
      *width = *width - (MAX2(ctx->Convolution2D.Width, 1) - 1);
      *height = *height - (MAX2(ctx->Convolution2D.Height, 1) - 1);
   }
   else if (ctx->Pixel.Separable2DEnabled
            && dimensions > 1
            && ctx->Pixel.ConvolutionBorderMode[2] == GL_REDUCE) {
      *width = *width - (MAX2(ctx->Separable2D.Width, 1) - 1);
      *height = *height - (MAX2(ctx->Separable2D.Height, 1) - 1);
   }
}



/*
 * This function is used to move user image data into a texture image.
 * We handle full texture images and subtexture images.  We also take
 * care of all image transfer operations here, including convolution.
 * Input:
 *         dstXoffset, dstYoffset, dstZoffset - offsets in pixels
 *         dstRowStride, dstImageStride - strides in GLchan's
 */
static void
fill_texture_image( GLcontext *ctx, GLuint dimensions,
                    GLenum texFormat, GLchan *texAddr,
                    GLint srcWidth, GLint srcHeight, GLint srcDepth,
                    GLint dstXoffset, GLint dstYoffset, GLint dstZoffset,
                    GLint dstRowStride, GLint dstImageStride,
                    GLenum srcFormat, GLenum srcType, const GLvoid *srcAddr,
                    const struct gl_pixelstore_attrib *srcPacking)
{
   GLint texComponents;

   ASSERT(ctx);
   ASSERT(dimensions >= 1 && dimensions <= 3);
   ASSERT(texAddr);
   ASSERT(srcWidth >= 1);
   ASSERT(srcHeight >= 1);
   ASSERT(srcDepth >= 1);
   ASSERT(dstXoffset >= 0);
   ASSERT(dstYoffset >= 0);
   ASSERT(dstZoffset >= 0);
   ASSERT(dstRowStride >= 0);
   ASSERT(dstImageStride >= 0);
   ASSERT(srcAddr);
   ASSERT(srcPacking);

   texComponents = components_in_intformat(texFormat);

   /* try common 2D texture cases first */
   if (!ctx->_ImageTransferState && dimensions == 2
       && srcType == GL_UNSIGNED_BYTE) {

      if (srcFormat == texFormat) {
         /* This will cover the common GL_RGB, GL_RGBA, GL_ALPHA,
          * GL_LUMINANCE_ALPHA, etc. texture formats.  Use memcpy().
          */
         const GLchan *src = (const GLchan *) _mesa_image_address(
                                   srcPacking, srcAddr, srcWidth, srcHeight,
                                   srcFormat, srcType, 0, 0, 0);
         const GLint srcRowStride = _mesa_image_row_stride(srcPacking,
                                               srcWidth, srcFormat, srcType);
         const GLint widthInBytes = srcWidth * texComponents * sizeof(GLchan);
         GLchan *dst = texAddr + dstYoffset * dstRowStride
                      + dstXoffset * texComponents;
         if (srcRowStride == widthInBytes && dstRowStride == widthInBytes) {
            MEMCPY(dst, src, srcHeight * widthInBytes);
         }
         else {
            GLint i;
            for (i = 0; i < srcHeight; i++) {
               MEMCPY(dst, src, widthInBytes);
               src += srcRowStride;
               dst += dstRowStride;
            }
         }
         return;  /* all done */
      }
      else if (srcFormat == GL_RGBA && texFormat == GL_RGB) {
         /* commonly used by Quake */
         const GLchan *src = (const GLchan *) _mesa_image_address(
                                   srcPacking, srcAddr, srcWidth, srcHeight,
                                   srcFormat, srcType, 0, 0, 0);
         const GLint srcRowStride = _mesa_image_row_stride(srcPacking,
                                               srcWidth, srcFormat, srcType);
         GLchan *dst = texAddr + dstYoffset * dstRowStride
                      + dstXoffset * texComponents;
         GLint i, j;
         for (i = 0; i < srcHeight; i++) {
            const GLchan *s = src;
            GLchan *d = dst;
            for (j = 0; j < srcWidth; j++) {
               *d++ = *s++;  /*red*/
               *d++ = *s++;  /*green*/
               *d++ = *s++;  /*blue*/
               s++;          /*alpha*/
            }
            src += srcRowStride;
            dst += dstRowStride;
         }
         return;  /* all done */
      }
   }

   /*
    * General case solutions
    */
   if (texFormat == GL_COLOR_INDEX) {
      /* color index texture */
      const GLenum texType = GL_UNSIGNED_BYTE;
      GLint img, row;
      GLchan *dest = texAddr + dstZoffset * dstImageStride
                    + dstYoffset * dstRowStride
                    + dstXoffset * texComponents;
      for (img = 0; img < srcDepth; img++) {
         GLchan *destRow = dest;
         for (row = 0; row < srcHeight; row++) {
            const GLvoid *src = _mesa_image_address(srcPacking,
                srcAddr, srcWidth, srcHeight, srcFormat, srcType, img, row, 0);
            _mesa_unpack_index_span(ctx, srcWidth, texType, destRow,
                                    srcType, src, srcPacking,
                                    ctx->_ImageTransferState);
            destRow += dstRowStride;
         }
         dest += dstImageStride;
      }
   }
   else {
      /* regular, color texture */
      if ((dimensions == 1 && ctx->Pixel.Convolution1DEnabled) ||
          (dimensions >= 2 && ctx->Pixel.Convolution2DEnabled) ||
          (dimensions >= 2 && ctx->Pixel.Separable2DEnabled)) {
         /*
          * Fill texture image with convolution
          */
         GLint img, row;
         GLint convWidth = srcWidth, convHeight = srcHeight;
         GLfloat *tmpImage, *convImage;
         tmpImage = (GLfloat *) MALLOC(srcWidth * srcHeight * 4 * sizeof(GLfloat));
         if (!tmpImage) {
            gl_error(ctx, GL_OUT_OF_MEMORY, "glTexImage");
            return;
         }
         convImage = (GLfloat *) MALLOC(srcWidth * srcHeight * 4 * sizeof(GLfloat));
         if (!convImage) {
            gl_error(ctx, GL_OUT_OF_MEMORY, "glTexImage");
            FREE(tmpImage);
            return;
         }

         for (img = 0; img < srcDepth; img++) {
            const GLfloat *srcf;
            GLfloat *dstf = tmpImage;
            GLchan *dest;

            /* unpack and do transfer ops up to convolution */
            for (row = 0; row < srcHeight; row++) {
               const GLvoid *src = _mesa_image_address(srcPacking,
                                              srcAddr, srcWidth, srcHeight,
                                              srcFormat, srcType, img, row, 0);
               _mesa_unpack_float_color_span(ctx, srcWidth, GL_RGBA, dstf,
                          srcFormat, srcType, src, srcPacking,
                          ctx->_ImageTransferState & IMAGE_PRE_CONVOLUTION_BITS,
                          GL_TRUE);
               dstf += srcWidth * 4;
            }

            /* convolve */
            if (dimensions == 1) {
               ASSERT(ctx->Pixel.Convolution1DEnabled);
               _mesa_convolve_1d_image(ctx, &convWidth, tmpImage, convImage);
            }
            else {
               if (ctx->Pixel.Convolution2DEnabled) {
                  _mesa_convolve_2d_image(ctx, &convWidth, &convHeight,
                                          tmpImage, convImage);
               }
               else {
                  ASSERT(ctx->Pixel.Separable2DEnabled);
                  _mesa_convolve_sep_image(ctx, &convWidth, &convHeight,
                                           tmpImage, convImage);
               }
            }

            /* packing and transfer ops after convolution */
            srcf = convImage;
            dest = texAddr + (dstZoffset + img) * dstImageStride
                 + dstYoffset * dstRowStride;
            for (row = 0; row < convHeight; row++) {
               _mesa_pack_float_rgba_span(ctx, convWidth,
                                          (const GLfloat (*)[4]) srcf,
                                          texFormat, GL_UNSIGNED_BYTE,
                                          dest, &_mesa_native_packing,
                                          ctx->_ImageTransferState
                                          & IMAGE_POST_CONVOLUTION_BITS);
               srcf += convWidth * 4;
               dest += dstRowStride;
            }
         }

         FREE(convImage);
         FREE(tmpImage);
      }
      else {
         /*
          * no convolution
          */
         GLint img, row;
         GLchan *dest = texAddr + dstZoffset * dstImageStride
                       + dstYoffset * dstRowStride
                       + dstXoffset * texComponents;
         for (img = 0; img < srcDepth; img++) {
            GLchan *destRow = dest;
            for (row = 0; row < srcHeight; row++) {
               const GLvoid *srcRow = _mesa_image_address(srcPacking,
                                              srcAddr, srcWidth, srcHeight,
                                              srcFormat, srcType, img, row, 0);
               _mesa_unpack_chan_color_span(ctx, srcWidth, texFormat, destRow,
                                       srcFormat, srcType, srcRow, srcPacking,
                                       ctx->_ImageTransferState);
               destRow += dstRowStride;
            }
            dest += dstImageStride;
         }
      }
   }
}



/* Need this to prevent an out-of-bounds memory access when using
 * X86 optimized code.
 */
#ifdef USE_X86_ASM
#  define EXTRA_BYTE sizeof(GLchan)
#else
#  define EXTRA_BYTE 0
#endif



/*
 * Called by glTexImage[123]D.  Fill in a texture image with data given
 * by the client.  All pixel transfer and unpack modes are handled here.
 * Input:  dimensions (1, 2, or 3)
 *         texImage - destination texture image (we'll malloc the memory)
 *         width, height, depth - size of source image
 *         srcFormat, srcType - source image format and type
 *         pixels - source image data
 *         srcPacking - source image packing parameters
 *
 * NOTE: All texture image parameters should have already been error checked.
 *
 * NOTE: the texImage dimensions and source image dimensions must be correct
 * with respect to convolution with border mode = reduce.
 */
static void
make_texture_image( GLcontext *ctx, GLuint dimensions,
                    struct gl_texture_image *texImage,
                    GLint width, GLint height, GLint depth,
                    GLenum srcFormat, GLenum srcType, const GLvoid *pixels,
                    const struct gl_pixelstore_attrib *srcPacking)
{
   const GLint internalFormat = texImage->IntFormat;
   const GLint components = components_in_intformat(internalFormat);
   GLint convWidth = width, convHeight = height;

   if (ctx->NewState & _NEW_PIXEL)
      gl_update_state(ctx);

   if (ctx->_ImageTransferState & IMAGE_CONVOLUTION_BIT) {
      adjust_texture_size_for_convolution(ctx, dimensions,
                                          &convWidth, &convHeight);
   }

   texImage->Data = (GLchan *) MALLOC(convWidth * convHeight * depth
                                 * components * sizeof(GLchan) + EXTRA_BYTE);
   if (!texImage->Data)
      return;      /* out of memory */

   fill_texture_image(ctx, dimensions, texImage->Format, texImage->Data,
                      width, height, depth, 0, 0, 0,
                      convWidth * components * sizeof(GLchan),
                      convWidth * convHeight * components * sizeof(GLchan),
                      srcFormat, srcType, pixels, srcPacking);
}



/*
 * glTexImage[123]D can accept a NULL image pointer.  In this case we
 * create a texture image with unspecified image contents per the OpenGL
 * spec.  This function creates an empty image for the given texture image.
 */
static void
make_null_texture( struct gl_texture_image *texImage )
{
   GLint components;
   GLint numPixels;

   ASSERT(texImage);
   ASSERT(!texImage->Data);

   components = components_in_intformat(texImage->IntFormat);
   numPixels = texImage->Width * texImage->Height * texImage->Depth;

   texImage->Data = (GLchan *) MALLOC( numPixels * components * sizeof(GLchan)
                                       + EXTRA_BYTE );

   /*
    * Let's see if anyone finds this.  If glTexImage2D() is called with
    * a NULL image pointer then load the texture image with something
    * interesting instead of leaving it indeterminate.
    */
   if (texImage->Data) {
      static const char message[8][32] = {
         "   X   X  XXXXX   XXX     X    ",
         "   XX XX  X      X   X   X X   ",
         "   X X X  X      X      X   X  ",
         "   X   X  XXXX    XXX   XXXXX  ",
         "   X   X  X          X  X   X  ",
         "   X   X  X      X   X  X   X  ",
         "   X   X  XXXXX   XXX   X   X  ",
         "                               "
      };

      GLchan *imgPtr = texImage->Data;
      GLint i, j, k;
      for (i = 0; i < texImage->Height; i++) {
         GLint srcRow = 7 - i % 8;
         for (j = 0; j < texImage->Width; j++) {
            GLint srcCol = j % 32;
            GLint texel = (message[srcRow][srcCol]=='X') ? CHAN_MAX : 70;
            for (k=0;k<components;k++) {
               *imgPtr++ = (GLchan) texel;
            }
         }
      }
   }
}



/*
 * This is called when a proxy texture test fails, we set all the
 * image members (except DriverData) to zero.
 */
static void
clear_proxy_teximage(struct gl_texture_image *img)
{
   ASSERT(img);
   img->Format = 0;
   img->IntFormat = 0;
   img->RedBits = 0;
   img->GreenBits = 0;
   img->BlueBits = 0;
   img->AlphaBits = 0;
   img->IntensityBits = 0;
   img->LuminanceBits = 0;
   img->IndexBits = 0;
   img->Border = 0;
   img->Width = 0;
   img->Height = 0;
   img->Depth = 0;
   img->Width2 = 0;
   img->Height2 = 0;
   img->Depth2 = 0;
   img->WidthLog2 = 0;
   img->HeightLog2 = 0;
   img->DepthLog2 = 0;
   img->Data = NULL;
   img->IsCompressed = 0;
   img->CompressedSize = 0;
}



/*
 * Test glTexImage[123]D() parameters for errors.
 * Input:
 *         dimensions - must be 1 or 2 or 3
 * Return:  GL_TRUE = an error was detected, GL_FALSE = no errors
 */
static GLboolean
texture_error_check( GLcontext *ctx, GLenum target,
                     GLint level, GLint internalFormat,
                     GLenum format, GLenum type,
                     GLuint dimensions,
                     GLint width, GLint height,
                     GLint depth, GLint border )
{
   GLboolean isProxy;
   GLint iformat;

   if (dimensions == 1) {
      isProxy = (GLboolean) (target == GL_PROXY_TEXTURE_1D);
      if (target != GL_TEXTURE_1D && !isProxy) {
         gl_error( ctx, GL_INVALID_ENUM, "glTexImage1D(target)" );
         return GL_TRUE;
      }
   }
   else if (dimensions == 2) {
      isProxy = (GLboolean) (target == GL_PROXY_TEXTURE_2D);
      if (target != GL_TEXTURE_2D && !isProxy &&
          !(ctx->Extensions.ARB_texture_cube_map &&
            target >= GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB &&
            target <= GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB)) {
          gl_error( ctx, GL_INVALID_ENUM, "glTexImage2D(target)" );
          return GL_TRUE;
      }
   }
   else if (dimensions == 3) {
      isProxy = (GLboolean) (target == GL_PROXY_TEXTURE_3D);
      if (target != GL_TEXTURE_3D && !isProxy) {
         gl_error( ctx, GL_INVALID_ENUM, "glTexImage3D(target)" );
         return GL_TRUE;
      }
   }
   else {
      gl_problem( ctx, "bad dims in texture_error_check" );
      return GL_TRUE;
   }

   /* Border */
   if (border != 0 && border != 1) {
      if (!isProxy) {
         char message[100];
         sprintf(message, "glTexImage%dD(border=%d)", dimensions, border);
         gl_error(ctx, GL_INVALID_VALUE, message);
      }
      return GL_TRUE;
   }

   /* Width */
   if (width < 2 * border || width > 2 + ctx->Const.MaxTextureSize
       || logbase2( width - 2 * border ) < 0) {
      if (!isProxy) {
         char message[100];
         sprintf(message, "glTexImage%dD(width=%d)", dimensions, width);
         gl_error(ctx, GL_INVALID_VALUE, message);
      }
      return GL_TRUE;
   }

   /* Height */
   if (dimensions >= 2) {
      if (height < 2 * border || height > 2 + ctx->Const.MaxTextureSize
          || logbase2( height - 2 * border ) < 0) {
         if (!isProxy) {
            char message[100];
            sprintf(message, "glTexImage%dD(height=%d)", dimensions, height);
            gl_error(ctx, GL_INVALID_VALUE, message);
         }
         return GL_TRUE;
      }
   }

   /* For cube map, width must equal height */
   if (target >= GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB &&
       target <= GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB) {
      if (width != height) {
         if (!isProxy) {
            gl_error(ctx, GL_INVALID_VALUE, "glTexImage2D(width != height)");
         }
         return GL_TRUE;
      }
   }

   /* Depth */
   if (dimensions >= 3) {
      if (depth < 2 * border || depth > 2 + ctx->Const.MaxTextureSize
          || logbase2( depth - 2 * border ) < 0) {
         if (!isProxy) {
            char message[100];
            sprintf(message, "glTexImage3D(depth=%d)", depth );
            gl_error( ctx, GL_INVALID_VALUE, message );
         }
         return GL_TRUE;
      }
   }

   /* Level */
   if (level < 0 || level >= ctx->Const.MaxTextureLevels) {
      if (!isProxy) {
         char message[100];
         sprintf(message, "glTexImage%dD(level=%d)", dimensions, level);
         gl_error(ctx, GL_INVALID_VALUE, message);
      }
      return GL_TRUE;
   }

   iformat = _mesa_base_tex_format( ctx, internalFormat );
   if (iformat < 0) {
      if (!isProxy) {
         char message[100];
         sprintf(message, "glTexImage%dD(internalFormat=0x%x)", dimensions,
                 internalFormat);
         gl_error(ctx, GL_INVALID_VALUE, message);
      }
      return GL_TRUE;
   }

   if (!is_compressed_format(ctx, internalFormat)) {
      if (!_mesa_is_legal_format_and_type( format, type )) {
         /* Yes, generate GL_INVALID_OPERATION, not GL_INVALID_ENUM, if there
          * is a type/format mismatch.  See 1.2 spec page 94, sec 3.6.4.
          */
         if (!isProxy) {
            char message[100];
            sprintf(message, "glTexImage%dD(format or type)", dimensions);
            gl_error(ctx, GL_INVALID_OPERATION, message);
         }
         return GL_TRUE;
      }
   }

   /* if we get here, the parameters are OK */
   return GL_FALSE;
}



/*
 * Test glTexSubImage[123]D() parameters for errors.
 * Input:
 *         dimensions - must be 1 or 2 or 3
 * Return:  GL_TRUE = an error was detected, GL_FALSE = no errors
 */
static GLboolean
subtexture_error_check( GLcontext *ctx, GLuint dimensions,
                        GLenum target, GLint level,
                        GLint xoffset, GLint yoffset, GLint zoffset,
                        GLint width, GLint height, GLint depth,
                        GLenum format, GLenum type )
{
   struct gl_texture_unit *texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
   struct gl_texture_image *destTex;

   if (dimensions == 1) {
      if (target != GL_TEXTURE_1D) {
         gl_error( ctx, GL_INVALID_ENUM, "glTexSubImage1D(target)" );
         return GL_TRUE;
      }
   }
   else if (dimensions == 2) {
      if (ctx->Extensions.ARB_texture_cube_map) {
         if ((target < GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB ||
              target > GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB) &&
             target != GL_TEXTURE_2D) {
            gl_error( ctx, GL_INVALID_ENUM, "glTexSubImage2D(target)" );
            return GL_TRUE;
         }
      }
      else if (target != GL_TEXTURE_2D) {
         gl_error( ctx, GL_INVALID_ENUM, "glTexSubImage2D(target)" );
         return GL_TRUE;
      }
   }
   else if (dimensions == 3) {
      if (target != GL_TEXTURE_3D) {
         gl_error( ctx, GL_INVALID_ENUM, "glTexSubImage3D(target)" );
         return GL_TRUE;
      }
   }
   else {
      gl_problem( ctx, "bad dims in texture_error_check" );
      return GL_TRUE;
   }

   if (level < 0 || level >= ctx->Const.MaxTextureLevels) {
      char message[100];
      sprintf(message, "glTexSubImage2D(level=%d)", level);
      gl_error(ctx, GL_INVALID_ENUM, message);
      return GL_TRUE;
   }

   if (width < 0) {
      char message[100];
      sprintf(message, "glTexSubImage%dD(width=%d)", dimensions, width);
      gl_error(ctx, GL_INVALID_VALUE, message);
      return GL_TRUE;
   }
   if (height < 0 && dimensions > 1) {
      char message[100];
      sprintf(message, "glTexSubImage%dD(height=%d)", dimensions, height);
      gl_error(ctx, GL_INVALID_VALUE, message);
      return GL_TRUE;
   }
   if (depth < 0 && dimensions > 2) {
      char message[100];
      sprintf(message, "glTexSubImage%dD(depth=%d)", dimensions, depth);
      gl_error(ctx, GL_INVALID_VALUE, message);
      return GL_TRUE;
   }

   destTex = texUnit->Current2D->Image[level];
   if (!destTex) {
      gl_error(ctx, GL_INVALID_OPERATION, "glTexSubImage2D");
      return GL_TRUE;
   }

   if (xoffset < -((GLint)destTex->Border)) {
      gl_error(ctx, GL_INVALID_VALUE, "glTexSubImage1/2/3D(xoffset)");
      return GL_TRUE;
   }
   if (xoffset + width > (GLint) (destTex->Width + destTex->Border)) {
      gl_error(ctx, GL_INVALID_VALUE, "glTexSubImage1/2/3D(xoffset+width)");
      return GL_TRUE;
   }
   if (dimensions > 1) {
      if (yoffset < -((GLint)destTex->Border)) {
         gl_error(ctx, GL_INVALID_VALUE, "glTexSubImage2/3D(yoffset)");
         return GL_TRUE;
      }
      if (yoffset + height > (GLint) (destTex->Height + destTex->Border)) {
         gl_error(ctx, GL_INVALID_VALUE, "glTexSubImage2/3D(yoffset+height)");
         return GL_TRUE;
      }
   }
   if (dimensions > 2) {
      if (zoffset < -((GLint)destTex->Border)) {
         gl_error(ctx, GL_INVALID_VALUE, "glTexSubImage3D(zoffset)");
         return GL_TRUE;
      }
      if (zoffset + depth  > (GLint) (destTex->Depth+destTex->Border)) {
         gl_error(ctx, GL_INVALID_VALUE, "glTexSubImage3D(zoffset+depth)");
         return GL_TRUE;
      }
   }

   if (!is_compressed_format(ctx, destTex->IntFormat)) {
      if (!_mesa_is_legal_format_and_type(format, type)) {
         char message[100];
         sprintf(message, "glTexSubImage%dD(format or type)", dimensions);
         gl_error(ctx, GL_INVALID_ENUM, message);
         return GL_TRUE;
      }
   }

   return GL_FALSE;
}


/*
 * Test glCopyTexImage[12]D() parameters for errors.
 * Input:  dimensions - must be 1 or 2 or 3
 * Return:  GL_TRUE = an error was detected, GL_FALSE = no errors
 */
static GLboolean
copytexture_error_check( GLcontext *ctx, GLuint dimensions,
                         GLenum target, GLint level, GLint internalFormat,
                         GLint width, GLint height, GLint border )
{
   GLint iformat;

   if (dimensions == 1) {
      if (target != GL_TEXTURE_1D) {
         gl_error( ctx, GL_INVALID_ENUM, "glCopyTexImage1D(target)" );
         return GL_TRUE;
      }
   }
   else if (dimensions == 2) {
      if (ctx->Extensions.ARB_texture_cube_map) {
         if ((target < GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB ||
              target > GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB) &&
             target != GL_TEXTURE_2D) {
            gl_error( ctx, GL_INVALID_ENUM, "glCopyTexImage2D(target)" );
            return GL_TRUE;
         }
      }
      else if (target != GL_TEXTURE_2D) {
         gl_error( ctx, GL_INVALID_ENUM, "glCopyTexImage2D(target)" );
         return GL_TRUE;
      }
   }

   /* Border */
   if (border!=0 && border!=1) {
      char message[100];
      sprintf(message, "glCopyTexImage%dD(border)", dimensions);
      gl_error(ctx, GL_INVALID_VALUE, message);
      return GL_TRUE;
   }

   /* Width */
   if (width < 2 * border || width > 2 + ctx->Const.MaxTextureSize
       || logbase2( width - 2 * border ) < 0) {
      char message[100];
      sprintf(message, "glCopyTexImage%dD(width=%d)", dimensions, width);
      gl_error(ctx, GL_INVALID_VALUE, message);
      return GL_TRUE;
   }

   /* Height */
   if (dimensions >= 2) {
      if (height < 2 * border || height > 2 + ctx->Const.MaxTextureSize
          || logbase2( height - 2 * border ) < 0) {
         char message[100];
         sprintf(message, "glCopyTexImage%dD(height=%d)", dimensions, height);
         gl_error(ctx, GL_INVALID_VALUE, message);
         return GL_TRUE;
      }
   }

   /* For cube map, width must equal height */
   if (target >= GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB &&
       target <= GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB) {
      if (width != height) {
         gl_error(ctx, GL_INVALID_VALUE, "glCopyTexImage2D(width != height)");
         return GL_TRUE;
      }
   }

   /* Level */
   if (level<0 || level>=ctx->Const.MaxTextureLevels) {
      char message[100];
      sprintf(message, "glCopyTexImage%dD(level=%d)", dimensions, level);
      gl_error(ctx, GL_INVALID_VALUE, message);
      return GL_TRUE;
   }

   iformat = _mesa_base_tex_format( ctx, internalFormat );
   if (iformat < 0) {
      char message[100];
      sprintf(message, "glCopyTexImage%dD(internalFormat)", dimensions);
      gl_error(ctx, GL_INVALID_VALUE, message);
      return GL_TRUE;
   }

   /* if we get here, the parameters are OK */
   return GL_FALSE;
}


static GLboolean
copytexsubimage_error_check( GLcontext *ctx, GLuint dimensions,
                             GLenum target, GLint level,
                             GLint xoffset, GLint yoffset, GLint zoffset,
                             GLsizei width, GLsizei height )
{
   struct gl_texture_unit *texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
   struct gl_texture_image *teximage;

   if (dimensions == 1) {
      if (target != GL_TEXTURE_1D) {
         gl_error( ctx, GL_INVALID_ENUM, "glCopyTexSubImage1D(target)" );
         return GL_TRUE;
      }
   }
   else if (dimensions == 2) {
      if (ctx->Extensions.ARB_texture_cube_map) {
         if ((target < GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB ||
              target > GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB) &&
             target != GL_TEXTURE_2D) {
            gl_error( ctx, GL_INVALID_ENUM, "glCopyTexSubImage2D(target)" );
            return GL_TRUE;
         }
      }
      else if (target != GL_TEXTURE_2D) {
         gl_error( ctx, GL_INVALID_ENUM, "glCopyTexSubImage2D(target)" );
         return GL_TRUE;
      }
   }
   else if (dimensions == 3) {
      if (target != GL_TEXTURE_3D) {
         gl_error( ctx, GL_INVALID_ENUM, "glCopyTexSubImage3D(target)" );
         return GL_TRUE;
      }
   }

   if (level < 0 || level >= ctx->Const.MaxTextureLevels) {
      char message[100];
      sprintf(message, "glCopyTexSubImage%dD(level=%d)", dimensions, level);
      gl_error(ctx, GL_INVALID_VALUE, message);
      return GL_TRUE;
   }

   if (width < 0) {
      char message[100];
      sprintf(message, "glCopyTexSubImage%dD(width=%d)", dimensions, width);
      gl_error(ctx, GL_INVALID_VALUE, message);
      return GL_TRUE;
   }
   if (dimensions > 1 && height < 0) {
      char message[100];
      sprintf(message, "glCopyTexSubImage%dD(height=%d)", dimensions, height);
      gl_error(ctx, GL_INVALID_VALUE, message);
      return GL_TRUE;
   }

   teximage = _mesa_select_tex_image(ctx, texUnit, target, level);
   if (!teximage) {
      char message[100];
      sprintf(message, "glCopyTexSubImage%dD(undefined texture)", dimensions);
      gl_error(ctx, GL_INVALID_OPERATION, message);
      return GL_TRUE;
   }

   if (xoffset < -((GLint)teximage->Border)) {
      char message[100];
      sprintf(message, "glCopyTexSubImage%dD(xoffset=%d)", dimensions, xoffset);
      gl_error(ctx, GL_INVALID_VALUE, message);
      return GL_TRUE;
   }
   if (xoffset+width > (GLint) (teximage->Width+teximage->Border)) {
      char message[100];
      sprintf(message, "glCopyTexSubImage%dD(xoffset+width)", dimensions);
      gl_error(ctx, GL_INVALID_VALUE, message);
      return GL_TRUE;
   }
   if (dimensions > 1) {
      if (yoffset < -((GLint)teximage->Border)) {
         char message[100];
         sprintf(message, "glCopyTexSubImage%dD(yoffset=%d)", dimensions, yoffset);
         gl_error(ctx, GL_INVALID_VALUE, message);
         return GL_TRUE;
      }
      /* NOTE: we're adding the border here, not subtracting! */
      if (yoffset+height > (GLint) (teximage->Height+teximage->Border)) {
         char message[100];
         sprintf(message, "glCopyTexSubImage%dD(yoffset+height)", dimensions);
         gl_error(ctx, GL_INVALID_VALUE, message);
         return GL_TRUE;
      }
   }

   if (dimensions > 2) {
      if (zoffset < -((GLint)teximage->Border)) {
         char message[100];
         sprintf(message, "glCopyTexSubImage%dD(zoffset)", dimensions);
         gl_error(ctx, GL_INVALID_VALUE, message);
         return GL_TRUE;
      }
      if (zoffset > (GLint) (teximage->Depth+teximage->Border)) {
         char message[100];
         sprintf(message, "glCopyTexSubImage%dD(zoffset+depth)", dimensions);
         gl_error(ctx, GL_INVALID_VALUE, message);
         return GL_TRUE;
      }
   }

   /* if we get here, the parameters are OK */
   return GL_FALSE;
}




/*
 * Turn generic compressed formats into specific compressed format.
 * Some of the compressed formats we don't support, so we
 * fall back to the uncompressed format.  (See issue 15 of
 * the GL_ARB_texture_compression specification.)
 */
static GLint
get_specific_compressed_tex_format(GLcontext *ctx,
                                   GLint ifmt, GLint numDimensions,
                                   GLint     *levelp,
                                   GLsizei   *widthp,
                                   GLsizei   *heightp,
                                   GLsizei   *depthp,
                                   GLint     *borderp,
                                   GLenum    *formatp,
                                   GLenum    *typep)
{
   char message[100];
   GLint internalFormat = ifmt;

   if (ctx->Extensions.ARB_texture_compression
       && ctx->Driver.SpecificCompressedTexFormat) {
      /*
       * First, ask the driver for the specific format.
       * We do this for all formats, since we may want to
       * fake one compressed format for another.
       */
       internalFormat = (*ctx->Driver.SpecificCompressedTexFormat)
                               (ctx, internalFormat, numDimensions,
                                levelp,
                                widthp, heightp, depthp,
                                borderp, formatp, typep);
   }

   /*
    * Now, convert any generic format left to an uncompressed
    * specific format.  If the driver does not support compression
    * of the format, we must drop back to the uncompressed format.
    * See issue 15 of the GL_ARB_texture_compression specification.
    */
   switch (internalFormat) {
      case GL_COMPRESSED_ALPHA_ARB:
         if (ctx && !ctx->Extensions.ARB_texture_compression) {
            sprintf(message, "glTexImage%dD(internalFormat)", numDimensions);
            gl_error(ctx, GL_INVALID_VALUE, message);
            return -1;
         }
         internalFormat = GL_ALPHA;
         break;
      case GL_COMPRESSED_LUMINANCE_ARB:
         if (ctx && !ctx->Extensions.ARB_texture_compression) {
            sprintf(message, "glTexImage%dD(internalFormat)", numDimensions);
            gl_error(ctx, GL_INVALID_VALUE, message);
            return -1;
         }
         internalFormat = GL_LUMINANCE;
         break;
      case GL_COMPRESSED_LUMINANCE_ALPHA_ARB:
         if (ctx && !ctx->Extensions.ARB_texture_compression) {
            sprintf(message, "glTexImage%dD(internalFormat)", numDimensions);
            gl_error(ctx, GL_INVALID_VALUE, message);
            return -1;
         }
         internalFormat = GL_LUMINANCE_ALPHA;
         break;
      case GL_COMPRESSED_INTENSITY_ARB:
         if (ctx && !ctx->Extensions.ARB_texture_compression) {
            sprintf(message, "glTexImage%dD(internalFormat)", numDimensions);
            gl_error(ctx, GL_INVALID_VALUE, message);
            return -1;
         }
         internalFormat = GL_INTENSITY;
         break;
      case GL_COMPRESSED_RGB_ARB:
         if (ctx && !ctx->Extensions.ARB_texture_compression) {
            sprintf(message, "glTexImage%dD(internalFormat)", numDimensions);
            gl_error(ctx, GL_INVALID_VALUE, message);
            return -1;
         }
         internalFormat = GL_RGB;
         break;
      case GL_COMPRESSED_RGBA_ARB:
         if (ctx && !ctx->Extensions.ARB_texture_compression) {
            sprintf(message, "glTexImage%dD(internalFormat)", numDimensions);
            gl_error(ctx, GL_INVALID_VALUE, message);
            return -1;
         }
         internalFormat = GL_RGBA;
         break;
      default:
         /* silence compiler warning */
         ;
   }
   return internalFormat;
}


/*
 * Called from the API.  Note that width includes the border.
 */
void
_mesa_TexImage1D( GLenum target, GLint level, GLint internalFormat,
                  GLsizei width, GLint border, GLenum format,
                  GLenum type, const GLvoid *pixels )
{
   GLsizei postConvWidth;
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glTexImage1D");

   postConvWidth = width;
   adjust_texture_size_for_convolution(ctx, 1, &postConvWidth, NULL);

   if (target==GL_TEXTURE_1D) {
      struct gl_texture_unit *texUnit;
      struct gl_texture_object *texObj;
      struct gl_texture_image *texImage;
      GLint ifmt;

      ifmt = get_specific_compressed_tex_format(ctx, internalFormat, 1,
                                                &level,
                                                &width, 0, 0,
                                                &border, &format, &type);
      if (ifmt < 0) {
         /*
          * The error here is that we were sent a generic compressed
          * format, but the extension is not supported.
          */
         return;
      }
      else {
         internalFormat = ifmt;
      }

      if (texture_error_check(ctx, target, level, internalFormat,
                              format, type, 1, postConvWidth, 1, 1, border)) {
         return;   /* error in texture image was detected */
      }

      texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
      texObj = texUnit->Current1D;
      texImage = texObj->Image[level];

      if (!texImage) {
         texImage = _mesa_alloc_texture_image();
         texObj->Image[level] = texImage;
         if (!texImage) {
            gl_error(ctx, GL_OUT_OF_MEMORY, "glTexImage1D");
            return;
         }
      }
      else if (texImage->Data) {
         FREE(texImage->Data);
         texImage->Data = NULL;
      }

      /* setup the teximage struct's fields */
      init_texture_image(ctx, texImage, postConvWidth, 1, 1, border, internalFormat);

      if (ctx->NewState & _NEW_PIXEL)
         gl_update_state(ctx);

      /* process the texture image */
      if (pixels) {
         GLboolean retain = GL_TRUE;
         GLboolean success = GL_FALSE;
         if (!ctx->_ImageTransferState && ctx->Driver.TexImage1D) {
            /* let device driver try to use raw image */
            success = (*ctx->Driver.TexImage1D)( ctx, target, level, format,
                                                 type, pixels, &ctx->Unpack,
                                                 texObj, texImage, &retain);
         }
         if (retain || !success) {
            /* make internal copy of the texture image */
            make_texture_image(ctx, 1, texImage, width, 1, 1,
                               format, type, pixels, &ctx->Unpack);
            if (!success && ctx->Driver.TexImage1D) {
               /* let device driver try to use unpacked image */
               (*ctx->Driver.TexImage1D)( ctx, target, level, texImage->Format,
                                          GL_UNSIGNED_BYTE, texImage->Data,
                                          &_mesa_native_packing,
                                          texObj, texImage, &retain);
            }
         }
         if (!retain && texImage->Data) {
            FREE(texImage->Data);
            texImage->Data = NULL;
         }
      }
      else {
         make_null_texture(texImage);
         if (ctx->Driver.TexImage1D) {
            GLboolean retain;
            (*ctx->Driver.TexImage1D)( ctx, target, level, texImage->Format,
                                       GL_UNSIGNED_BYTE, texImage->Data,
                                       &_mesa_native_packing,
                                       texObj, texImage, &retain);
         }
      }

      /* state update */
      texObj->Complete = GL_FALSE;
      ctx->NewState |= _NEW_TEXTURE;
   }
   else if (target == GL_PROXY_TEXTURE_1D) {
      /* Proxy texture: check for errors and update proxy state */
      GLenum error = texture_error_check(ctx, target, level, internalFormat,
                                         format, type, 1, width, 1, 1, border);
      if (!error && ctx->Driver.TestProxyTexImage) {
         error = !(*ctx->Driver.TestProxyTexImage)(ctx, target, level,
                                                  internalFormat, format, type,
                                                  width, 1, 1, border);
      }
      if (error) {
         /* if error, clear all proxy texture image parameters */
         if (level>=0 && level<ctx->Const.MaxTextureLevels) {
            clear_proxy_teximage(ctx->Texture.Proxy1D->Image[level]);
         }
      }
      else {
         /* if no error, update proxy texture image parameters */
         init_texture_image(ctx, ctx->Texture.Proxy1D->Image[level],
                            width, 1, 1, border, internalFormat);
      }
   }
   else {
      gl_error( ctx, GL_INVALID_ENUM, "glTexImage1D(target)" );
      return;
   }
}


void
_mesa_TexImage2D( GLenum target, GLint level, GLint internalFormat,
                  GLsizei width, GLsizei height, GLint border,
                  GLenum format, GLenum type,
                  const GLvoid *pixels )
{
   GLsizei postConvWidth, postConvHeight;
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glTexImage2D");

   postConvWidth = width;
   postConvHeight = height;
   adjust_texture_size_for_convolution(ctx, 2, &postConvWidth,&postConvHeight);

   if (target==GL_TEXTURE_2D ||
       (ctx->Extensions.ARB_texture_cube_map &&
        target >= GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB &&
        target <= GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB)) {
      struct gl_texture_unit *texUnit;
      struct gl_texture_object *texObj;
      struct gl_texture_image *texImage;
      GLint ifmt;

      ifmt = get_specific_compressed_tex_format(ctx, internalFormat, 2,
                                                &level,
                                                &width, &height, 0,
                                                &border, &format, &type);
      if (ifmt < 0) {
         /*
          * The error here is that we were sent a generic compressed
          * format, but the extension is not supported.
          */
         return;
      }
      else {
         internalFormat = ifmt;
      }

      if (texture_error_check(ctx, target, level, internalFormat,
                              format, type, 2, postConvWidth, postConvHeight,
                              1, border)) {
         return;   /* error in texture image was detected */
      }

      texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
      texObj = _mesa_select_tex_object(ctx, texUnit, target);
      texImage = _mesa_select_tex_image(ctx, texUnit, target, level);

      if (!texImage) {
         texImage = _mesa_alloc_texture_image();
         set_tex_image(texObj, target, level, texImage);
         /*texObj->Image[level] = texImage;*/
         if (!texImage) {
            gl_error(ctx, GL_OUT_OF_MEMORY, "glTexImage2D");
            return;
         }
      }
      else if (texImage->Data) {
         FREE(texImage->Data);
         texImage->Data = NULL;
      }

      /* setup the teximage struct's fields */
      init_texture_image(ctx, texImage, postConvWidth, postConvHeight,
                         1, border, internalFormat);

      if (ctx->NewState & _NEW_PIXEL)
         gl_update_state(ctx);

      /* process the texture image */
      if (pixels) {
         GLboolean retain = GL_TRUE;
         GLboolean success = GL_FALSE;
         if (!ctx->_ImageTransferState && ctx->Driver.TexImage2D) {
            /* let device driver try to use raw image */
            success = (*ctx->Driver.TexImage2D)( ctx, target, level, format,
                                                 type, pixels, &ctx->Unpack,
                                                 texObj, texImage, &retain);
         }
         if (retain || !success) {
            /* make internal copy of the texture image */
            make_texture_image(ctx, 2, texImage, width, height, 1,
                               format, type, pixels, &ctx->Unpack);
            if (!success && ctx->Driver.TexImage2D) {
               /* let device driver try to use unpacked image */
               (*ctx->Driver.TexImage2D)( ctx, target, level, texImage->Format,
                                          GL_UNSIGNED_BYTE, texImage->Data,
                                          &_mesa_native_packing,
                                          texObj, texImage, &retain);
            }
         }
         if (!retain && texImage->Data) {
            FREE(texImage->Data);
            texImage->Data = NULL;
         }
      }
      else {
         make_null_texture(texImage);
         if (ctx->Driver.TexImage2D) {
            GLboolean retain;
            (*ctx->Driver.TexImage2D)( ctx, target, level, texImage->Format,
                                       GL_UNSIGNED_BYTE, texImage->Data,
                                       &_mesa_native_packing,
                                       texObj, texImage, &retain);
         }
      }

      /* state update */
      texObj->Complete = GL_FALSE;
      ctx->NewState |= _NEW_TEXTURE;
   }
   else if (target == GL_PROXY_TEXTURE_2D) {
      /* Proxy texture: check for errors and update proxy state */
      GLenum error = texture_error_check(ctx, target, level, internalFormat,
                                    format, type, 2, width, height, 1, border);
      if (!error && ctx->Driver.TestProxyTexImage) {
         error = !(*ctx->Driver.TestProxyTexImage)(ctx, target, level,
                                                  internalFormat, format, type,
                                                  width, height, 1, border);
      }
      if (error) {
         /* if error, clear all proxy texture image parameters */
         if (level>=0 && level<ctx->Const.MaxTextureLevels) {
            clear_proxy_teximage(ctx->Texture.Proxy2D->Image[level]);
         }
      }
      else {
         /* if no error, update proxy texture image parameters */
         init_texture_image(ctx,
                            ctx->Texture.Proxy2D->Image[level],
                            width, height, 1, border, internalFormat);
      }
   }
   else {
      gl_error( ctx, GL_INVALID_ENUM, "glTexImage2D(target)" );
      return;
   }
}


/*
 * Called by the API or display list executor.
 * Note that width and height include the border.
 */
void
_mesa_TexImage3D( GLenum target, GLint level, GLint internalFormat,
                  GLsizei width, GLsizei height, GLsizei depth,
                  GLint border, GLenum format, GLenum type,
                  const GLvoid *pixels )
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glTexImage3D");

   if (target==GL_TEXTURE_3D_EXT) {
      struct gl_texture_unit *texUnit;
      struct gl_texture_object *texObj;
      struct gl_texture_image *texImage;
      GLint ifmt;

      ifmt = get_specific_compressed_tex_format(ctx, internalFormat, 3,
                                                &level,
                                                &width, &height, &depth,
                                                &border, &format, &type);
      if (ifmt < 0) {
         /*
          * The error here is that we were sent a generic compressed
          * format, but the extension is not supported.
          */
         return;
      }
      else {
         internalFormat = ifmt;
      }

      if (texture_error_check(ctx, target, level, internalFormat,
                              format, type, 3, width, height, depth, border)) {
         return;   /* error in texture image was detected */
      }

      texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
      texObj = texUnit->Current3D;
      texImage = texObj->Image[level];

      if (!texImage) {
         texImage = _mesa_alloc_texture_image();
         texObj->Image[level] = texImage;
         if (!texImage) {
            gl_error(ctx, GL_OUT_OF_MEMORY, "glTexImage3D");
            return;
         }
      }
      else if (texImage->Data) {
         FREE(texImage->Data);
         texImage->Data = NULL;
      }

      /* setup the teximage struct's fields */
      init_texture_image(ctx, texImage, width, height, depth,
                         border, internalFormat);

      if (ctx->NewState & _NEW_PIXEL)
         gl_update_state(ctx);

      /* process the texture image */
      if (pixels) {
         GLboolean retain = GL_TRUE;
         GLboolean success = GL_FALSE;
         if (!ctx->_ImageTransferState && ctx->Driver.TexImage3D) {
            /* let device driver try to use raw image */
            success = (*ctx->Driver.TexImage3D)( ctx, target, level, format,
                                                 type, pixels, &ctx->Unpack,
                                                 texObj, texImage, &retain);
         }
         if (retain || !success) {
            /* make internal copy of the texture image */
            make_texture_image(ctx, 3, texImage, width, height, depth,
                               format, type, pixels, &ctx->Unpack);
            if (!success && ctx->Driver.TexImage3D) {
               /* let device driver try to use unpacked image */
               (*ctx->Driver.TexImage3D)( ctx, target, level, texImage->Format,
                                          GL_UNSIGNED_BYTE, texImage->Data,
                                          &_mesa_native_packing,
                                          texObj, texImage, &retain);
            }
         }
         if (!retain && texImage->Data) {
            FREE(texImage->Data);
            texImage->Data = NULL;
         }
      }
      else {
         make_null_texture(texImage);
         if (ctx->Driver.TexImage3D) {
            GLboolean retain;
            (*ctx->Driver.TexImage3D)( ctx, target, level, texImage->Format,
                                       GL_UNSIGNED_BYTE, texImage->Data,
                                       &_mesa_native_packing,
                                       texObj, texImage, &retain);
         }
      }

      /* state update */
      texObj->Complete = GL_FALSE;
      ctx->NewState |= _NEW_TEXTURE;
   }
   else if (target == GL_PROXY_TEXTURE_3D) {
      /* Proxy texture: check for errors and update proxy state */
      GLenum error = texture_error_check(ctx, target, level, internalFormat,
                                format, type, 3, width, height, depth, border);
      if (!error && ctx->Driver.TestProxyTexImage) {
         error = !(*ctx->Driver.TestProxyTexImage)(ctx, target, level,
                                                 internalFormat, format, type,
                                                 width, height, depth, border);
      }
      if (error) {
         /* if error, clear all proxy texture image parameters */
         if (level>=0 && level<ctx->Const.MaxTextureLevels) {
            clear_proxy_teximage(ctx->Texture.Proxy3D->Image[level]);
         }
      }
      else {
         /* if no error, update proxy texture image parameters */
         init_texture_image(ctx, ctx->Texture.Proxy3D->Image[level],
                            width, height, depth, border, internalFormat);
      }
   }
   else {
      gl_error( ctx, GL_INVALID_ENUM, "glTexImage3D(target)" );
      return;
   }
}


void
_mesa_TexImage3DEXT( GLenum target, GLint level, GLenum internalFormat,
                     GLsizei width, GLsizei height, GLsizei depth,
                     GLint border, GLenum format, GLenum type,
                     const GLvoid *pixels )
{
   _mesa_TexImage3D(target, level, (GLint) internalFormat, width, height,
                    depth, border, format, type, pixels);
}


/*
 * Fetch a texture image from the device driver.
 * Store the results in the given texture object at the given mipmap level.
 */
void
_mesa_get_teximage_from_driver( GLcontext *ctx, GLenum target, GLint level,
                                const struct gl_texture_object *texObj )
{
   GLvoid *image;
   GLenum imgFormat, imgType;
   GLboolean freeImage;
   struct gl_texture_image *texImage;
   GLint destComponents, numPixels, srcBytesPerTexel;

   if (!ctx->Driver.GetTexImage)
      return;

   image = (*ctx->Driver.GetTexImage)( ctx, target, level, texObj,
                                       &imgFormat, &imgType, &freeImage);
   if (!image)
      return;

   texImage = texObj->Image[level];
   ASSERT(texImage);
   if (!texImage)
      return;

   destComponents = components_in_intformat(texImage->Format);
   assert(destComponents > 0);
   numPixels = texImage->Width * texImage->Height * texImage->Depth;
   assert(numPixels > 0);
   srcBytesPerTexel = _mesa_bytes_per_pixel(imgFormat, imgType);
   assert(srcBytesPerTexel > 0);

   if (!texImage->Data) {
      /* Allocate memory for the texture image data */
      texImage->Data = (GLchan *) MALLOC(numPixels * destComponents
                                         * sizeof(GLchan) + EXTRA_BYTE);
   }

   if (imgFormat == texImage->Format && imgType == GL_UNSIGNED_BYTE) {
      /* We got lucky!  The driver's format and type match Mesa's format. */
      if (texImage->Data) {
         MEMCPY(texImage->Data, image, numPixels * destComponents);
      }
   }
   else {
      /* Convert the texture image from the driver's format to Mesa's
       * internal format.
       */
      const GLint width = texImage->Width;
      const GLint height = texImage->Height;
      const GLint depth = texImage->Depth;
      const GLint destBytesPerRow = width * destComponents * sizeof(GLchan);
      const GLint srcBytesPerRow = width * srcBytesPerTexel;
      const GLenum dstType = GL_UNSIGNED_BYTE;
      const GLenum dstFormat = texImage->Format;
      const GLchan *srcPtr = (const GLchan *) image;
      GLchan *destPtr = texImage->Data;

      if (texImage->Format == GL_COLOR_INDEX) {
         /* color index texture */
         GLint img, row;
         assert(imgFormat == GL_COLOR_INDEX);
         for (img = 0; img < depth; img++) {
            for (row = 0; row < height; row++) {
               _mesa_unpack_index_span(ctx, width, dstType, destPtr,
                             imgType, srcPtr, &_mesa_native_packing, GL_FALSE);
               destPtr += destBytesPerRow;
               srcPtr += srcBytesPerRow;
            }
         }
      }
      else {
         /* color texture */
         GLint img, row;
         for (img = 0; img < depth; img++) {
            for (row = 0; row < height; row++) {
               _mesa_unpack_chan_color_span(ctx, width, dstFormat, destPtr,
                  imgFormat, imgType, srcPtr, &_mesa_native_packing, GL_FALSE);
               destPtr += destBytesPerRow;
               srcPtr += srcBytesPerRow;
            }
         }
      }
   }

   if (freeImage)
      FREE(image);
}


/*
 * Get all the mipmap images for a texture object from the device driver.
 * Actually, only get mipmap images if we're using a mipmap filter.
 */
GLboolean
_mesa_get_teximages_from_driver(GLcontext *ctx,
                                struct gl_texture_object *texObj)
{
   if (ctx->Driver.GetTexImage) {
      static const GLenum targets[] = {
         GL_TEXTURE_1D,
         GL_TEXTURE_2D,
         GL_TEXTURE_3D,
         GL_TEXTURE_CUBE_MAP_ARB,
         GL_TEXTURE_CUBE_MAP_ARB,
         GL_TEXTURE_CUBE_MAP_ARB
      };
      GLboolean needLambda = (texObj->MinFilter != texObj->MagFilter);
      GLenum target = targets[texObj->Dimensions - 1];
      if (needLambda) {
         GLint level;
         /* Get images for all mipmap levels.  We might not need them
          * all but this is easier.  We're on a (slow) software path
          * anyway.
          */
         for (level = 0; level <= texObj->_P; level++) {
            struct gl_texture_image *texImg = texObj->Image[level];
            if (texImg && !texImg->Data) {
               _mesa_get_teximage_from_driver(ctx, target, level, texObj);
               if (!texImg->Data)
                  return GL_FALSE;  /* out of memory */
            }
         }
      }
      else {
         GLint level = texObj->BaseLevel;
         struct gl_texture_image *texImg = texObj->Image[level];
         if (texImg && !texImg->Data) {
            _mesa_get_teximage_from_driver(ctx, target, level, texObj);
            if (!texImg->Data)
               return GL_FALSE;  /* out of memory */
         }
      }
      return GL_TRUE;
   }
   return GL_FALSE;
}



void
_mesa_GetTexImage( GLenum target, GLint level, GLenum format,
                   GLenum type, GLvoid *pixels )
{
   GET_CURRENT_CONTEXT(ctx);
   const struct gl_texture_unit *texUnit;
   const struct gl_texture_object *texObj;
   struct gl_texture_image *texImage;
   GLboolean discardImage;

   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glGetTexImage");

   if (level < 0 || level >= ctx->Const.MaxTextureLevels) {
      gl_error( ctx, GL_INVALID_VALUE, "glGetTexImage(level)" );
      return;
   }

   if (_mesa_sizeof_type(type) <= 0) {
      gl_error( ctx, GL_INVALID_ENUM, "glGetTexImage(type)" );
      return;
   }

   if (_mesa_components_in_format(format) <= 0) {
      gl_error( ctx, GL_INVALID_ENUM, "glGetTexImage(format)" );
      return;
   }

   if (!pixels)
      return;

   texUnit = &(ctx->Texture.Unit[ctx->Texture.CurrentUnit]);
   texObj = _mesa_select_tex_object(ctx, texUnit, target);
   if (!texObj ||
       target == GL_PROXY_TEXTURE_1D ||
       target == GL_PROXY_TEXTURE_2D ||
       target == GL_PROXY_TEXTURE_3D) {
      gl_error(ctx, GL_INVALID_ENUM, "glGetTexImage(target)");
      return;
   }

   texImage = _mesa_select_tex_image(ctx, texUnit, target, level);
   if (!texImage) {
      /* invalid mipmap level, not an error */
      return;
   }

   if (!texImage->Data) {
      /* try to get the texture image from the device driver */
      _mesa_get_teximage_from_driver(ctx, target, level, texObj);
      discardImage = GL_TRUE;
   }
   else {
      discardImage = GL_FALSE;
   }

   if (texImage->Data) {
      GLint width = texImage->Width;
      GLint height = texImage->Height;
      GLint depth = texImage->Depth;
      GLint img, row;

      if (ctx->NewState & _NEW_PIXEL)
         gl_update_state(ctx);

      if (ctx->_ImageTransferState & IMAGE_CONVOLUTION_BIT) {
         /* convert texture image to GL_RGBA, GL_FLOAT */
         GLfloat *tmpImage, *convImage;
         const GLint comps = components_in_intformat(texImage->Format);

         tmpImage = (GLfloat *) MALLOC(width * height * 4 * sizeof(GLfloat));
         if (!tmpImage) {
            gl_error(ctx, GL_OUT_OF_MEMORY, "glGetTexImage");
            return;
         }
         convImage = (GLfloat *) MALLOC(width * height * 4 * sizeof(GLfloat));
         if (!convImage) {
            FREE(tmpImage);
            gl_error(ctx, GL_OUT_OF_MEMORY, "glGetTexImage");
            return;
         }

         for (img = 0; img < depth; img++) {
            GLint convWidth, convHeight;

            /* convert to GL_RGBA */
            for (row = 0; row < height; row++) {
               const GLchan *src = texImage->Data
                                  + (img * height + row ) * width * comps;
               GLfloat *dst = tmpImage + row * width * 4;
               _mesa_unpack_float_color_span(ctx, width, GL_RGBA, dst,
                          texImage->Format, GL_UNSIGNED_BYTE,
                          src, &_mesa_native_packing,
                          ctx->_ImageTransferState & IMAGE_PRE_CONVOLUTION_BITS,
                          GL_FALSE);
            }

            convWidth = width;
            convHeight = height;

            /* convolve */
            if (target == GL_TEXTURE_1D) {
               if (ctx->Pixel.Convolution1DEnabled) {
                  _mesa_convolve_1d_image(ctx, &convWidth, tmpImage, convImage);
               }
            }
            else {
               if (ctx->Pixel.Convolution2DEnabled) {
                  _mesa_convolve_2d_image(ctx, &convWidth, &convHeight,
                                          tmpImage, convImage);
               }
               else if (ctx->Pixel.Separable2DEnabled) {
                  _mesa_convolve_sep_image(ctx, &convWidth, &convHeight,
                                           tmpImage, convImage);
               }
            }

            /* pack convolved image */
            for (row = 0; row < convHeight; row++) {
               const GLfloat *src = convImage + row * convWidth * 4;
               GLvoid *dest = _mesa_image_address(&ctx->Pack, pixels,
                                                  convWidth, convHeight,
                                                  format, type, img, row, 0);
               _mesa_pack_float_rgba_span(ctx, convWidth,
                        (const GLfloat(*)[4]) src,
                        format, type, dest, &ctx->Pack,
                        ctx->_ImageTransferState & IMAGE_POST_CONVOLUTION_BITS);
            }
         }

         FREE(tmpImage);
         FREE(convImage);
      }
      else {
         /* no convolution */
         for (img = 0; img < depth; img++) {
            for (row = 0; row < height; row++) {
               /* compute destination address in client memory */
               GLvoid *dest = _mesa_image_address( &ctx->Unpack, pixels,
                                  width, height, format, type, img, row, 0);
               assert(dest);
               if (texImage->Format == GL_RGBA) {
                  /* simple case */
                  const GLchan *src = texImage->Data
                                     + (img * height + row ) * width * 4;
                  _mesa_pack_rgba_span( ctx, width, (CONST GLchan (*)[4]) src,
                                        format, type, dest, &ctx->Pack,
                                        ctx->_ImageTransferState );
               }
               else {
                  /* general case:  convert row to RGBA format */
                  GLchan rgba[MAX_WIDTH][4];
                  GLint i;
                  const GLchan *src;
                  switch (texImage->Format) {
                     case GL_ALPHA:
                        src = texImage->Data + row * width;
                        for (i = 0; i < width; i++) {
                           rgba[i][RCOMP] = CHAN_MAX;
                           rgba[i][GCOMP] = CHAN_MAX;
                           rgba[i][BCOMP] = CHAN_MAX;
                           rgba[i][ACOMP] = src[i];
                        }
                        break;
                     case GL_LUMINANCE:
                        src = texImage->Data + row * width;
                        for (i = 0; i < width; i++) {
                           rgba[i][RCOMP] = src[i];
                           rgba[i][GCOMP] = src[i];
                           rgba[i][BCOMP] = src[i];
                           rgba[i][ACOMP] = CHAN_MAX;
                         }
                        break;
                     case GL_LUMINANCE_ALPHA:
                        src = texImage->Data + row * 2 * width;
                        for (i = 0; i < width; i++) {
                           rgba[i][RCOMP] = src[i*2+0];
                           rgba[i][GCOMP] = src[i*2+0];
                           rgba[i][BCOMP] = src[i*2+0];
                           rgba[i][ACOMP] = src[i*2+1];
                        }
                        break;
                     case GL_INTENSITY:
                        src = texImage->Data + row * width;
                        for (i = 0; i < width; i++) {
                           rgba[i][RCOMP] = src[i];
                           rgba[i][GCOMP] = src[i];
                           rgba[i][BCOMP] = src[i];
                           rgba[i][ACOMP] = CHAN_MAX;
                        }
                        break;
                     case GL_RGB:
                        src = texImage->Data + row * 3 * width;
                        for (i = 0; i < width; i++) {
                           rgba[i][RCOMP] = src[i*3+0];
                           rgba[i][GCOMP] = src[i*3+1];
                           rgba[i][BCOMP] = src[i*3+2];
                           rgba[i][ACOMP] = CHAN_MAX;
                        }
                        break;
                     case GL_COLOR_INDEX:
                        gl_problem( ctx, "GL_COLOR_INDEX not implemented in gl_GetTexImage" );
                        break;
                     case GL_RGBA:
                     default:
                        gl_problem( ctx, "bad format in gl_GetTexImage" );
                  }
                  _mesa_pack_rgba_span( ctx, width, (const GLchan (*)[4])rgba,
                                        format, type, dest, &ctx->Pack,
                                        ctx->_ImageTransferState );
               } /* format */
            } /* row */
         } /* img */
      } /* convolution */

      /* if we got the teximage from the device driver we'll discard it now */
      if (discardImage) {
         FREE(texImage->Data);
         texImage->Data = NULL;
      }
   }
}



void
_mesa_TexSubImage1D( GLenum target, GLint level,
                     GLint xoffset, GLsizei width,
                     GLenum format, GLenum type,
                     const GLvoid *pixels )
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_texture_unit *texUnit;
   struct gl_texture_object *texObj;
   struct gl_texture_image *texImage;
   GLboolean success = GL_FALSE;
   GLsizei postConvWidth;

   postConvWidth = width;
   adjust_texture_size_for_convolution(ctx, 1, &postConvWidth, NULL);

   if (subtexture_error_check(ctx, 1, target, level, xoffset, 0, 0,
                              postConvWidth, 1, 1, format, type)) {
      return;   /* error was detected */
   }

   texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
   texObj = texUnit->Current1D;
   texImage = texObj->Image[level];
   assert(texImage);

   if (width == 0 || !pixels)
      return;  /* no-op, not an error */

   if (ctx->NewState & _NEW_PIXEL)
      gl_update_state(ctx);

   if (!ctx->_ImageTransferState && ctx->Driver.TexSubImage1D) {
      success = (*ctx->Driver.TexSubImage1D)( ctx, target, level, xoffset,
                                              width, format, type, pixels,
                                              &ctx->Unpack, texObj, texImage );
   }
   if (!success) {
      /* XXX if Driver.TexSubImage1D, unpack image and try again? */
      GLboolean retain = GL_TRUE;
      if (!texImage->Data) {
         _mesa_get_teximage_from_driver( ctx, target, level, texObj );
         if (!texImage->Data) {
            make_null_texture(texImage);
         }
         if (!texImage->Data)
            return;  /* we're really out of luck! */
      }

      fill_texture_image(ctx, 1, texImage->Format, texImage->Data,
                         width, 1, 1, xoffset + texImage->Border, 0, 0, /* size and offsets */
                         0, 0, /* strides */
                         format, type, pixels, &ctx->Unpack);

      if (ctx->Driver.TexImage1D) {
         (*ctx->Driver.TexImage1D)( ctx, target, level, texImage->Format,
                                    GL_UNSIGNED_BYTE, texImage->Data,
                                    &_mesa_native_packing, texObj, texImage,
                                    &retain );
      }

      if (!retain && texImage->Data) {
         FREE(texImage->Data);
         texImage->Data = NULL;
      }
   }
}


void
_mesa_TexSubImage2D( GLenum target, GLint level,
                     GLint xoffset, GLint yoffset,
                     GLsizei width, GLsizei height,
                     GLenum format, GLenum type,
                     const GLvoid *pixels )
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_texture_unit *texUnit;
   struct gl_texture_object *texObj;
   struct gl_texture_image *texImage;
   GLboolean success = GL_FALSE;
   GLsizei postConvWidth, postConvHeight;

   postConvWidth = width;
   postConvHeight = height;
   adjust_texture_size_for_convolution(ctx, 2, &postConvWidth,&postConvHeight);

   if (subtexture_error_check(ctx, 2, target, level, xoffset, yoffset, 0,
                             postConvWidth, postConvHeight, 1, format, type)) {
      return;   /* error was detected */
   }

   texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
   texObj = _mesa_select_tex_object(ctx, texUnit, target);
   texImage = texObj->Image[level];
   assert(texImage);

   if (width == 0 || height == 0 || !pixels)
      return;  /* no-op, not an error */

   if (ctx->NewState & _NEW_PIXEL)
      gl_update_state(ctx);

   if (!ctx->_ImageTransferState && ctx->Driver.TexSubImage2D) {
      success = (*ctx->Driver.TexSubImage2D)( ctx, target, level, xoffset,
                                     yoffset, width, height, format, type,
                                     pixels, &ctx->Unpack, texObj, texImage );
   }
   if (!success) {
      /* XXX if Driver.TexSubImage2D, unpack image and try again? */
      const GLint texComps = components_in_intformat(texImage->Format);
      const GLint texRowStride = texImage->Width * texComps;
      GLboolean retain = GL_TRUE;

      if (!texImage->Data) {
         _mesa_get_teximage_from_driver( ctx, target, level, texObj );
         if (!texImage->Data) {
            make_null_texture(texImage);
         }
         if (!texImage->Data)
            return;  /* we're really out of luck! */
      }

      fill_texture_image(ctx, 2, texImage->Format, texImage->Data,
                         width, height, 1, xoffset + texImage->Border,
                         yoffset + texImage->Border, 0, texRowStride, 0,
                         format, type, pixels, &ctx->Unpack);

      if (ctx->Driver.TexImage2D) {
         (*ctx->Driver.TexImage2D)(ctx, target, level, texImage->Format,
                                   GL_UNSIGNED_BYTE, texImage->Data,
                                   &_mesa_native_packing, texObj, texImage,
                                   &retain);
      }

      if (!retain && texImage->Data) {
         FREE(texImage->Data);
         texImage->Data = NULL;
      }
   }
}



void
_mesa_TexSubImage3D( GLenum target, GLint level,
                     GLint xoffset, GLint yoffset, GLint zoffset,
                     GLsizei width, GLsizei height, GLsizei depth,
                     GLenum format, GLenum type,
                     const GLvoid *pixels )
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_texture_unit *texUnit;
   struct gl_texture_object *texObj;
   struct gl_texture_image *texImage;
   GLboolean success = GL_FALSE;

   if (subtexture_error_check(ctx, 3, target, level, xoffset, yoffset, zoffset,
                              width, height, depth, format, type)) {
      return;   /* error was detected */
   }

   texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
   texObj = texUnit->Current3D;
   texImage = texObj->Image[level];
   assert(texImage);

   if (width == 0 || height == 0 || height == 0 || !pixels)
      return;  /* no-op, not an error */

   if (ctx->NewState & _NEW_PIXEL)
      gl_update_state(ctx);

   if (!ctx->_ImageTransferState && ctx->Driver.TexSubImage3D) {
      success = (*ctx->Driver.TexSubImage3D)( ctx, target, level, xoffset,
                                yoffset, zoffset, width, height, depth, format,
                                type, pixels, &ctx->Unpack, texObj, texImage );
   }
   if (!success) {
      /* XXX if Driver.TexSubImage3D, unpack image and try again? */
      const GLint texComps = components_in_intformat(texImage->Format);
      const GLint texRowStride = texImage->Width * texComps;
      const GLint texImgStride = texRowStride * texImage->Height;
      GLboolean retain = GL_TRUE;

      if (!texImage->Data) {
         _mesa_get_teximage_from_driver( ctx, target, level, texObj );
         if (!texImage->Data) {
            make_null_texture(texImage);
         }
         if (!texImage->Data)
            return;  /* we're really out of luck! */
      }

      fill_texture_image(ctx, 3, texImage->Format, texImage->Data,
                         width, height, depth, xoffset + texImage->Border,
                         yoffset + texImage->Border,
                         zoffset + texImage->Border, texRowStride,
                         texImgStride, format, type, pixels, &ctx->Unpack);

      if (ctx->Driver.TexImage3D) {
         (*ctx->Driver.TexImage3D)(ctx, target, level, texImage->Format,
                                   GL_UNSIGNED_BYTE, texImage->Data,
                                   &_mesa_native_packing, texObj, texImage,
                                   &retain);
      }

      if (!retain && texImage->Data) {
         FREE(texImage->Data);
         texImage->Data = NULL;
      }
   }
}



/*
 * Read an RGBA image from the frame buffer.
 * This is used by glCopyTex[Sub]Image[12]D().
 * Input:  ctx - the context
 *         x, y - lower left corner
 *         width, height - size of region to read
 * Return: pointer to block of GL_RGBA, GLchan data.
 */
static GLchan *
read_color_image( GLcontext *ctx, GLint x, GLint y,
                  GLsizei width, GLsizei height )
{
   GLint stride, i;
   GLchan *image, *dst;

   image = (GLchan *) MALLOC(width * height * 4 * sizeof(GLchan));
   if (!image)
      return NULL;

   /* Select buffer to read from */
   (*ctx->Driver.SetReadBuffer)( ctx, ctx->ReadBuffer,
                                 ctx->Pixel.DriverReadBuffer );

   RENDER_START(ctx);

   dst = image;
   stride = width * 4;
   for (i = 0; i < height; i++) {
      gl_read_rgba_span( ctx, ctx->ReadBuffer, width, x, y + i,
                         (GLchan (*)[4]) dst );
      dst += stride;
   }

   RENDER_FINISH(ctx);

   /* Read from draw buffer (the default) */
   (*ctx->Driver.SetReadBuffer)( ctx, ctx->DrawBuffer,
                                 ctx->Color.DriverDrawBuffer );

   return image;
}



void
_mesa_CopyTexImage1D( GLenum target, GLint level,
                      GLenum internalFormat,
                      GLint x, GLint y,
                      GLsizei width, GLint border )
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glCopyTexImage1D");

   if (copytexture_error_check(ctx, 1, target, level, internalFormat,
                               width, 1, border))
      return;

   if (ctx->NewState & _NEW_PIXEL)
      gl_update_state(ctx);

   if (ctx->_ImageTransferState || !ctx->Driver.CopyTexImage1D
       || !(*ctx->Driver.CopyTexImage1D)(ctx, target, level,
                         internalFormat, x, y, width, border)) {
      struct gl_pixelstore_attrib unpackSave;

      /* get image from framebuffer */
      GLchan *image = read_color_image( ctx, x, y, width, 1 );
      if (!image) {
         gl_error( ctx, GL_OUT_OF_MEMORY, "glCopyTexImage1D" );
         return;
      }

      /* call glTexImage1D to redefine the texture */
      unpackSave = ctx->Unpack;
      ctx->Unpack = _mesa_native_packing;
      (*ctx->Exec->TexImage1D)( target, level, internalFormat, width,
                                border, GL_RGBA, GL_UNSIGNED_BYTE, image );
      ctx->Unpack = unpackSave;

      FREE(image);
   }
}



void
_mesa_CopyTexImage2D( GLenum target, GLint level, GLenum internalFormat,
                      GLint x, GLint y, GLsizei width, GLsizei height,
                      GLint border )
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glCopyTexImage2D");

   if (copytexture_error_check(ctx, 2, target, level, internalFormat,
                               width, height, border))
      return;

   if (ctx->NewState & _NEW_PIXEL)
      gl_update_state(ctx);

   if (ctx->_ImageTransferState || !ctx->Driver.CopyTexImage2D
       || !(*ctx->Driver.CopyTexImage2D)(ctx, target, level,
                         internalFormat, x, y, width, height, border)) {
      struct gl_pixelstore_attrib unpackSave;

      /* get image from framebuffer */
      GLchan *image = read_color_image( ctx, x, y, width, height );
      if (!image) {
         gl_error( ctx, GL_OUT_OF_MEMORY, "glCopyTexImage2D" );
         return;
      }

      /* call glTexImage2D to redefine the texture */
      unpackSave = ctx->Unpack;
      ctx->Unpack = _mesa_native_packing;
      (ctx->Exec->TexImage2D)( target, level, internalFormat, width,
                      height, border, GL_RGBA, GL_UNSIGNED_BYTE, image );
      ctx->Unpack = unpackSave;

      FREE(image);
   }
}



void
_mesa_CopyTexSubImage1D( GLenum target, GLint level,
                         GLint xoffset, GLint x, GLint y, GLsizei width )
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glCopyTexSubImage1D");

   if (copytexsubimage_error_check(ctx, 1, target, level,
                                   xoffset, 0, 0, width, 1))
      return;

   if (ctx->NewState & _NEW_PIXEL)
      gl_update_state(ctx);

   if (ctx->_ImageTransferState || !ctx->Driver.CopyTexSubImage1D
       || !(*ctx->Driver.CopyTexSubImage1D)(ctx, target, level,
                                            xoffset, x, y, width)) {
      struct gl_texture_unit *texUnit;
      struct gl_texture_image *teximage;
      struct gl_pixelstore_attrib unpackSave;
      GLchan *image;

      texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
      teximage = texUnit->Current1D->Image[level];
      assert(teximage);

      /* get image from frame buffer */
      image = read_color_image(ctx, x, y, width, 1);
      if (!image) {
         gl_error( ctx, GL_OUT_OF_MEMORY, "glCopyTexSubImage2D" );
         return;
      }

      /* now call glTexSubImage1D to do the real work */
      unpackSave = ctx->Unpack;
      ctx->Unpack = _mesa_native_packing;
      _mesa_TexSubImage1D(target, level, xoffset, width,
                          GL_RGBA, GL_UNSIGNED_BYTE, image);
      ctx->Unpack = unpackSave;

      FREE(image);
   }
}



void
_mesa_CopyTexSubImage2D( GLenum target, GLint level,
                         GLint xoffset, GLint yoffset,
                         GLint x, GLint y, GLsizei width, GLsizei height )
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glCopyTexSubImage2D");

   if (copytexsubimage_error_check(ctx, 2, target, level,
                                   xoffset, yoffset, 0, width, height))
      return;

   if (ctx->NewState & _NEW_PIXEL)
      gl_update_state(ctx);

   if (ctx->_ImageTransferState || !ctx->Driver.CopyTexSubImage2D
       || !(*ctx->Driver.CopyTexSubImage2D)(ctx, target, level,
                                xoffset, yoffset, x, y, width, height )) {
      struct gl_texture_unit *texUnit;
      struct gl_texture_image *teximage;
      struct gl_pixelstore_attrib unpackSave;
      GLchan *image;

      texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
      teximage = texUnit->Current2D->Image[level];
      assert(teximage);

      /* get image from frame buffer */
      image = read_color_image(ctx, x, y, width, height);
      if (!image) {
         gl_error( ctx, GL_OUT_OF_MEMORY, "glCopyTexSubImage2D" );
         return;
      }

      /* now call glTexSubImage2D to do the real work */
      unpackSave = ctx->Unpack;
      ctx->Unpack = _mesa_native_packing;
      _mesa_TexSubImage2D(target, level, xoffset, yoffset, width, height,
                          GL_RGBA, GL_UNSIGNED_BYTE, image);
      ctx->Unpack = unpackSave;

      FREE(image);
   }
}



void
_mesa_CopyTexSubImage3D( GLenum target, GLint level,
                         GLint xoffset, GLint yoffset, GLint zoffset,
                         GLint x, GLint y, GLsizei width, GLsizei height )
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glCopyTexSubImage3D");

   if (copytexsubimage_error_check(ctx, 3, target, level,
                    xoffset, yoffset, zoffset, width, height))
      return;

   if (ctx->NewState & _NEW_PIXEL)
      gl_update_state(ctx);

   if (ctx->_ImageTransferState || !ctx->Driver.CopyTexSubImage3D
       || !(*ctx->Driver.CopyTexSubImage3D)(ctx, target, level,
                     xoffset, yoffset, zoffset, x, y, width, height )) {
      struct gl_texture_unit *texUnit;
      struct gl_texture_image *teximage;
      struct gl_pixelstore_attrib unpackSave;
      GLchan *image;

      texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
      teximage = texUnit->Current3D->Image[level];
      assert(teximage);

      /* get image from frame buffer */
      image = read_color_image(ctx, x, y, width, height);
      if (!image) {
         gl_error( ctx, GL_OUT_OF_MEMORY, "glCopyTexSubImage2D" );
         return;
      }

      /* now call glTexSubImage2D to do the real work */
      unpackSave = ctx->Unpack;
      ctx->Unpack = _mesa_native_packing;
      _mesa_TexSubImage3D(target, level, xoffset, yoffset, zoffset,
                          width, height, 1, GL_RGBA, GL_UNSIGNED_BYTE, image);
      ctx->Unpack = unpackSave;

      FREE(image);
   }
}



void
_mesa_CompressedTexImage1DARB(GLenum target, GLint level,
                              GLenum internalFormat, GLsizei width,
                              GLint border, GLsizei imageSize,
                              const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glCompressedTexImage1DARB");

   switch (internalFormat) {
      case GL_COMPRESSED_ALPHA_ARB:
      case GL_COMPRESSED_LUMINANCE_ARB:
      case GL_COMPRESSED_LUMINANCE_ALPHA_ARB:
      case GL_COMPRESSED_INTENSITY_ARB:
      case GL_COMPRESSED_RGB_ARB:
      case GL_COMPRESSED_RGBA_ARB:
         gl_error(ctx, GL_INVALID_ENUM, "glCompressedTexImage1DARB");
         return;
      default:
         /* silence compiler warning */
         ;
   }

   if (target == GL_TEXTURE_1D) {
      struct gl_texture_unit *texUnit;
      struct gl_texture_object *texObj;
      struct gl_texture_image *texImage;
      GLsizei computedImageSize;

      if (texture_error_check(ctx, target, level, internalFormat,
                              GL_NONE, GL_NONE, 1, width, 1, 1, border)) {
         return;   /* error in texture image was detected */
      }

      texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
      texObj = texUnit->Current1D;
      texImage = texObj->Image[level];

      if (!texImage) {
         texImage = _mesa_alloc_texture_image();
         texObj->Image[level] = texImage;
         if (!texImage) {
            gl_error(ctx, GL_OUT_OF_MEMORY, "glCompressedTexImage1DARB");
            return;
         }
      }
      else if (texImage->Data) {
         FREE(texImage->Data);
         texImage->Data = NULL;
      }

      /* setup the teximage struct's fields */
      init_texture_image(ctx, texImage, width, 1, 1,
                         border, internalFormat);

      /* process the texture image */
      if (data) {
         GLboolean retain = GL_TRUE;
         GLboolean success = GL_FALSE;
         if (ctx->Driver.CompressedTexImage1D) {
            success = (*ctx->Driver.CompressedTexImage1D)(ctx, target, level,
                               imageSize, data, texObj, texImage, &retain);
         }
         if (retain || !success) {
            /* make internal copy of the texture image */
            computedImageSize = _mesa_compressed_image_size(ctx,
                                                        internalFormat,
                                                        1,    /* num dims */
                                                        width,
                                                        1,    /* height   */
                                                        1);   /* depth    */
            if (computedImageSize != imageSize) {
                gl_error(ctx, GL_INVALID_VALUE, "glCompressedTexImage1DARB(imageSize)");
                return;
            }
            texImage->Data = MALLOC(computedImageSize);
            if (texImage->Data) {
               MEMCPY(texImage->Data, data, computedImageSize);
            }
         }
         if (!retain && texImage->Data) {
            FREE(texImage->Data);
            texImage->Data = NULL;
         }
      }
      else {
         make_null_texture(texImage);
         if (ctx->Driver.CompressedTexImage1D) {
            GLboolean retain;
            (*ctx->Driver.CompressedTexImage1D)(ctx, target, level, 0,
                                                texImage->Data, texObj,
                                                texImage, &retain);
         }
      }

      /* state update */
      texObj->Complete = GL_FALSE;
      ctx->NewState |= _NEW_TEXTURE;
   }
   else if (target == GL_PROXY_TEXTURE_1D) {
      /* Proxy texture: check for errors and update proxy state */
      GLenum error = texture_error_check(ctx, target, level, internalFormat,
                                    GL_NONE, GL_NONE, 1, width, 1, 1, border);
      if (!error && ctx->Driver.TestProxyTexImage) {
         error = !(*ctx->Driver.TestProxyTexImage)(ctx, target, level,
                                             internalFormat, GL_NONE, GL_NONE,
                                             width, 1, 1, border);
      }
      if (error) {
         /* if error, clear all proxy texture image parameters */
         if (level>=0 && level<ctx->Const.MaxTextureLevels) {
            clear_proxy_teximage(ctx->Texture.Proxy1D->Image[level]);
         }
      }
      else {
         /* if no error, update proxy texture image parameters */
         init_texture_image(ctx, ctx->Texture.Proxy1D->Image[level],
                            width, 1, 1, border, internalFormat);
      }
   }
   else {
      gl_error( ctx, GL_INVALID_ENUM, "glCompressedTexImage1DARB(target)" );
      return;
   }
}


void
_mesa_CompressedTexImage2DARB(GLenum target, GLint level,
                              GLenum internalFormat, GLsizei width,
                              GLsizei height, GLint border, GLsizei imageSize,
                              const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glCompressedTexImage2DARB");

   switch (internalFormat) {
      case GL_COMPRESSED_ALPHA_ARB:
      case GL_COMPRESSED_LUMINANCE_ARB:
      case GL_COMPRESSED_LUMINANCE_ALPHA_ARB:
      case GL_COMPRESSED_INTENSITY_ARB:
      case GL_COMPRESSED_RGB_ARB:
      case GL_COMPRESSED_RGBA_ARB:
         gl_error(ctx, GL_INVALID_ENUM, "glCompressedTexImage2DARB");
         return;
      default:
         /* silence compiler warning */
         ;
   }

   if (target==GL_TEXTURE_2D ||
       (ctx->Extensions.ARB_texture_cube_map &&
        target >= GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB &&
        target <= GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB)) {
      struct gl_texture_unit *texUnit;
      struct gl_texture_object *texObj;
      struct gl_texture_image *texImage;
      GLsizei computedImageSize;

      if (texture_error_check(ctx, target, level, internalFormat,
                              GL_NONE, GL_NONE, 1, width, height, 1, border)) {
         return;   /* error in texture image was detected */
      }

      texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
      texObj = texUnit->Current2D;
      texImage = texObj->Image[level];

      if (!texImage) {
         texImage = _mesa_alloc_texture_image();
         texObj->Image[level] = texImage;
         if (!texImage) {
            gl_error(ctx, GL_OUT_OF_MEMORY, "glCompressedTexImage2DARB");
            return;
         }
      }
      else if (texImage->Data) {
         FREE(texImage->Data);
         texImage->Data = NULL;
      }

      /* setup the teximage struct's fields */
      init_texture_image(ctx, texImage, width, height, 1, border, internalFormat);

      /* process the texture image */
      if (data) {
         GLboolean retain = GL_TRUE;
         GLboolean success = GL_FALSE;
         if (ctx->Driver.CompressedTexImage2D) {
            success = (*ctx->Driver.CompressedTexImage2D)( ctx,
                                                           target,
                                                           level,
                                                           imageSize,
                                                           data,
                                                           texObj,
                                                           texImage,
                                                           &retain);
         }
         if (retain || !success) {
            /* make internal copy of the texture image */
            computedImageSize = _mesa_compressed_image_size(ctx,
                                                           internalFormat,
                                                           2,    /* num dims */
                                                           width,
                                                           height,
                                                           1);   /* depth    */
            if (computedImageSize != imageSize) {
                gl_error(ctx, GL_INVALID_VALUE, "glCompressedTexImage2DARB(imageSize)");
                return;
            }
            texImage->Data = MALLOC(computedImageSize);
            if (texImage->Data) {
               MEMCPY(texImage->Data, data, computedImageSize);
            }
         }
         if (!retain && texImage->Data) {
            FREE(texImage->Data);
            texImage->Data = NULL;
         }
      }
      else {
         make_null_texture(texImage);
         if (ctx->Driver.CompressedTexImage2D) {
            GLboolean retain;
            (*ctx->Driver.CompressedTexImage2D)( ctx, target, level, 0,
                                                 texImage->Data, texObj,
                                                 texImage, &retain);
         }
      }

      /* state update */
      texObj->Complete = GL_FALSE;
      ctx->NewState |= _NEW_TEXTURE;
   }
   else if (target == GL_PROXY_TEXTURE_2D) {
      /* Proxy texture: check for errors and update proxy state */
      GLenum error = texture_error_check(ctx, target, level, internalFormat,
                                GL_NONE, GL_NONE, 2, width, height, 1, border);
      if (!error && ctx->Driver.TestProxyTexImage) {
         error = !(*ctx->Driver.TestProxyTexImage)(ctx, target, level,
                                              internalFormat, GL_NONE, GL_NONE,
                                              width, height, 1, border);
      }
      if (error) {
         /* if error, clear all proxy texture image parameters */
         if (level>=0 && level<ctx->Const.MaxTextureLevels) {
            clear_proxy_teximage(ctx->Texture.Proxy2D->Image[level]);
         }
      }
      else {
         /* if no error, update proxy texture image parameters */
         init_texture_image(ctx, ctx->Texture.Proxy2D->Image[level],
                            width, 1, 1, border, internalFormat);
      }
   }
   else {
      gl_error( ctx, GL_INVALID_ENUM, "glCompressedTexImage2DARB(target)" );
      return;
   }
}


void
_mesa_CompressedTexImage3DARB(GLenum target, GLint level,
                              GLenum internalFormat, GLsizei width,
                              GLsizei height, GLsizei depth, GLint border,
                              GLsizei imageSize, const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glCompressedTexImage3DARB");

   switch (internalFormat) {
      case GL_COMPRESSED_ALPHA_ARB:
      case GL_COMPRESSED_LUMINANCE_ARB:
      case GL_COMPRESSED_LUMINANCE_ALPHA_ARB:
      case GL_COMPRESSED_INTENSITY_ARB:
      case GL_COMPRESSED_RGB_ARB:
      case GL_COMPRESSED_RGBA_ARB:
         gl_error(ctx, GL_INVALID_ENUM, "glCompressedTexImage3DARB");
         return;
      default:
         /* silence compiler warning */
         ;
   }

   if (target == GL_TEXTURE_3D) {
      struct gl_texture_unit *texUnit;
      struct gl_texture_object *texObj;
      struct gl_texture_image *texImage;
      GLsizei computedImageSize;

      if (texture_error_check(ctx, target, level, internalFormat,
                          GL_NONE, GL_NONE, 1, width, height, depth, border)) {
         return;   /* error in texture image was detected */
      }

      texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
      texObj = texUnit->Current3D;
      texImage = texObj->Image[level];

      if (!texImage) {
         texImage = _mesa_alloc_texture_image();
         texObj->Image[level] = texImage;
         if (!texImage) {
            gl_error(ctx, GL_OUT_OF_MEMORY, "glCompressedTexImage3DARB");
            return;
         }
      }
      else if (texImage->Data) {
         FREE(texImage->Data);
         texImage->Data = NULL;
      }

      /* setup the teximage struct's fields */
      init_texture_image(ctx, texImage, width, height, depth,
                         border, internalFormat);

      /* process the texture image */
      if (data) {
         GLboolean retain = GL_TRUE;
         GLboolean success = GL_FALSE;
         if (ctx->Driver.CompressedTexImage3D) {
            success = (*ctx->Driver.CompressedTexImage3D)(ctx, target, level,
                                                          imageSize, data,
                                                          texObj, texImage,
                                                          &retain);
         }
         if (retain || !success) {
            /* make internal copy of the texture image */
            computedImageSize = _mesa_compressed_image_size(ctx,
                                                            internalFormat,
                                                            3,  /* num dims */
                                                            width,
                                                            height,
                                                            depth);
            if (computedImageSize != imageSize) {
                gl_error(ctx, GL_INVALID_VALUE, "glCompressedTexImage3DARB(imageSize)");
                return;
            }
            texImage->Data = MALLOC(computedImageSize);
            if (texImage->Data) {
               MEMCPY(texImage->Data, data, computedImageSize);
            }
         }
         if (!retain && texImage->Data) {
            FREE(texImage->Data);
            texImage->Data = NULL;
         }
      }
      else {
         make_null_texture(texImage);
         if (ctx->Driver.CompressedTexImage3D) {
            GLboolean retain;
            (*ctx->Driver.CompressedTexImage3D)( ctx, target, level, 0,
                                                 texImage->Data, texObj,
                                                 texImage, &retain);
         }
      }

      /* state update */
      texObj->Complete = GL_FALSE;
      ctx->NewState |= _NEW_TEXTURE;
   }
   else if (target == GL_PROXY_TEXTURE_3D) {
      /* Proxy texture: check for errors and update proxy state */
      GLenum error = texture_error_check(ctx, target, level, internalFormat,
                            GL_NONE, GL_NONE, 1, width, height, depth, border);
      if (!error && ctx->Driver.TestProxyTexImage) {
         error = !(*ctx->Driver.TestProxyTexImage)(ctx, target, level,
                                             internalFormat, GL_NONE, GL_NONE,
                                             width, height, depth, border);
      }
      if (error) {
         /* if error, clear all proxy texture image parameters */
         if (level>=0 && level<ctx->Const.MaxTextureLevels) {
            clear_proxy_teximage(ctx->Texture.Proxy3D->Image[level]);
         }
      }
      else {
         /* if no error, update proxy texture image parameters */
         init_texture_image(ctx, ctx->Texture.Proxy3D->Image[level],
                            width, 1, 1, border, internalFormat);
      }
   }
   else {
      gl_error( ctx, GL_INVALID_ENUM, "glCompressedTexImage3DARB(target)" );
      return;
   }
}


void
_mesa_CompressedTexSubImage1DARB(GLenum target, GLint level, GLint xoffset,
                                 GLsizei width, GLenum format,
                                 GLsizei imageSize, const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_texture_unit *texUnit;
   struct gl_texture_object *texObj;
   struct gl_texture_image *texImage;
   GLboolean success = GL_FALSE;

   if (subtexture_error_check(ctx, 1, target, level, xoffset, 0, 0,
                              width, 1, 1, format, GL_NONE)) {
      return;   /* error was detected */
   }

   texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
   texObj = _mesa_select_tex_object(ctx, texUnit, target);
   texImage = texObj->Image[level];
   assert(texImage);

   if (width == 0 || !data)
      return;  /* no-op, not an error */

   if (ctx->Driver.CompressedTexSubImage1D) {
      success = (*ctx->Driver.CompressedTexSubImage1D)(ctx, target, level,
                   xoffset, width, format, imageSize, data, texObj, texImage);
   }
   if (!success) {
      /* XXX what else can we do? */
      gl_problem(ctx, "glCompressedTexSubImage1DARB failed!");
      return;
   }
}


void
_mesa_CompressedTexSubImage2DARB(GLenum target, GLint level, GLint xoffset,
                                 GLint yoffset, GLsizei width, GLsizei height,
                                 GLenum format, GLsizei imageSize,
                                 const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_texture_unit *texUnit;
   struct gl_texture_object *texObj;
   struct gl_texture_image *texImage;
   GLboolean success = GL_FALSE;

   if (subtexture_error_check(ctx, 2, target, level, xoffset, yoffset, 0,
                              width, height, 1, format, GL_NONE)) {
      return;   /* error was detected */
   }

   texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
   texObj = _mesa_select_tex_object(ctx, texUnit, target);
   texImage = texObj->Image[level];
   assert(texImage);

   if (width == 0 || height == 0 || !data)
      return;  /* no-op, not an error */

   if (ctx->Driver.CompressedTexSubImage2D) {
      success = (*ctx->Driver.CompressedTexSubImage2D)(ctx, target, level,
                                       xoffset, yoffset, width, height, format,
                                       imageSize, data, texObj, texImage);
   }
   if (!success) {
      /* XXX what else can we do? */
      gl_problem(ctx, "glCompressedTexSubImage2DARB failed!");
      return;
   }
}


void
_mesa_CompressedTexSubImage3DARB(GLenum target, GLint level, GLint xoffset,
                                 GLint yoffset, GLint zoffset, GLsizei width,
                                 GLsizei height, GLsizei depth, GLenum format,
                                 GLsizei imageSize, const GLvoid *data)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_texture_unit *texUnit;
   struct gl_texture_object *texObj;
   struct gl_texture_image *texImage;
   GLboolean success = GL_FALSE;

   if (subtexture_error_check(ctx, 3, target, level, xoffset, yoffset, zoffset,
                              width, height, depth, format, GL_NONE)) {
      return;   /* error was detected */
   }

   texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
   texObj = _mesa_select_tex_object(ctx, texUnit, target);
   texImage = texObj->Image[level];
   assert(texImage);

   if (width == 0 || height == 0 || depth == 0 || !data)
      return;  /* no-op, not an error */

   if (ctx->Driver.CompressedTexSubImage3D) {
      success = (*ctx->Driver.CompressedTexSubImage3D)(ctx, target, level,
                               xoffset, yoffset, zoffset, width, height, depth,
                               format, imageSize, data, texObj, texImage);
   }
   if (!success) {
      /* XXX what else can we do? */
      gl_problem(ctx, "glCompressedTexSubImage3DARB failed!");
      return;
   }
}


void
_mesa_GetCompressedTexImageARB(GLenum target, GLint level, GLvoid *img)
{
   GET_CURRENT_CONTEXT(ctx);
   const struct gl_texture_object *texObj;
   struct gl_texture_image *texImage;

   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glGetCompressedTexImageARB");

   if (level < 0 || level >= ctx->Const.MaxTextureLevels) {
      gl_error( ctx, GL_INVALID_VALUE, "glGetCompressedTexImageARB(level)" );
      return;
   }

   switch (target) {
      case GL_TEXTURE_1D:
         texObj = ctx->Texture.Unit[ctx->Texture.CurrentUnit].Current1D;
         texImage = texObj->Image[level];
         break;
      case GL_TEXTURE_2D:
         texObj = ctx->Texture.Unit[ctx->Texture.CurrentUnit].Current2D;
         texImage = texObj->Image[level];
         break;
      case GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB:
         texObj = ctx->Texture.Unit[ctx->Texture.CurrentUnit].CurrentCubeMap;
         texImage = texObj->Image[level];
         break;
      case GL_TEXTURE_CUBE_MAP_NEGATIVE_X_ARB:
         texObj = ctx->Texture.Unit[ctx->Texture.CurrentUnit].CurrentCubeMap;
         texImage = texObj->NegX[level];
         break;
      case GL_TEXTURE_CUBE_MAP_POSITIVE_Y_ARB:
         texObj = ctx->Texture.Unit[ctx->Texture.CurrentUnit].CurrentCubeMap;
         texImage = texObj->PosY[level];
         break;
      case GL_TEXTURE_CUBE_MAP_NEGATIVE_Y_ARB:
         texObj = ctx->Texture.Unit[ctx->Texture.CurrentUnit].CurrentCubeMap;
         texImage = texObj->NegY[level];
         break;
      case GL_TEXTURE_CUBE_MAP_POSITIVE_Z_ARB:
         texObj = ctx->Texture.Unit[ctx->Texture.CurrentUnit].CurrentCubeMap;
         texImage = texObj->PosZ[level];
         break;
      case GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB:
         texObj = ctx->Texture.Unit[ctx->Texture.CurrentUnit].CurrentCubeMap;
         texImage = texObj->NegZ[level];
         break;
      case GL_TEXTURE_3D:
         texObj = ctx->Texture.Unit[ctx->Texture.CurrentUnit].Current3D;
         texImage = texObj->Image[level];
         break;
      default:
         gl_error(ctx, GL_INVALID_ENUM, "glGetCompressedTexImageARB(target)");
         return;
   }

   if (!texImage) {
      /* invalid mipmap level */
      gl_error(ctx, GL_INVALID_VALUE, "glGetCompressedTexImageARB(level)");
      return;
   }

   if (!texImage->IsCompressed) {
      gl_error(ctx, GL_INVALID_OPERATION, "glGetCompressedTexImageARB");
      return;
   }

   if (!img)
      return;

   if (ctx->Driver.GetCompressedTexImage) {
      (*ctx->Driver.GetCompressedTexImage)(ctx, target, level, img, texObj,
                                           texImage);
   }
   else {
      gl_problem(ctx, "Driver doesn't implement GetCompressedTexImage");
   }
}