Enable GL_ARB_texture_compression for XMesa/GLX driver. Texture

compression isn't really implmented.  Just updated glTexImageXD()
to accept compressed internal format tokens.

10 files changed, 283 insertions, 49 deletions

diff --git a/src/mesa/drivers/x11/xm_api.c b/src/mesa/drivers/x11/xm_api.c
index 9df18b25a1b..a487f229055 100644
--- a/src/mesa/drivers/x11/xm_api.c
+++ b/src/mesa/drivers/x11/xm_api.c
@@ -1,4 +1,4 @@
-/* $Id: xm_api.c,v 1.24 2001/06/04 22:33:02 brianp Exp $ */
+/* $Id: xm_api.c,v 1.25 2001/06/15 14:18:46 brianp Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -77,6 +77,8 @@
 #include "conf.h"
 #endif
 #include "macros.h"
+#include "texformat.h"
+#include "texstore.h"
 #include "swrast/swrast.h"
 #include "swrast_setup/swrast_setup.h"
 #include "array_cache/acache.h"
@@ -1634,6 +1636,10 @@ XMesaContext XMesaCreateContext( XMesaVisual v, XMesaContext share_list )
    }
 
    _mesa_enable_sw_extensions(ctx);
+   _mesa_enable_extension(ctx, "GL_ARB_texture_compression");
+   ctx->Driver.BaseCompressedTexFormat = _mesa_base_compressed_texformat;
+   ctx->Driver.CompressedTextureSize = _mesa_compressed_texture_size;
+   ctx->Driver.GetCompressedTexImage = _mesa_get_compressed_teximage;
 
    if (CHECK_BYTE_ORDER(v)) {
       c->swapbytes = GL_FALSE;
diff --git a/src/mesa/main/dd.h b/src/mesa/main/dd.h
index e69ad2d740f..d88e9d30551 100644
--- a/src/mesa/main/dd.h
+++ b/src/mesa/main/dd.h
@@ -1,4 +1,4 @@
-/* $Id: dd.h,v 1.61 2001/04/04 21:54:20 brianp Exp $ */
+/* $Id: dd.h,v 1.62 2001/06/15 14:18:46 brianp Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -346,16 +346,12 @@ struct dd_function_table {
     * should do the job.
     */
 
-   GLboolean (*IsCompressedFormat)(GLcontext *ctx, GLint internalFormat);
-   /* Called to tell if a format is a compressed format.
-    */
-
    void (*GetCompressedTexImage)( GLcontext *ctx, GLenum target,
-                                  GLint lod, void *image,
+                                  GLint level, void *image,
                                   const struct gl_texture_object *texObj,
                                   struct gl_texture_image *texImage );
    /* Called by glGetCompressedTexImageARB.
-    * <target>, <lod>, <image> are specified by user.
+    * <target>, <level>, <image> are specified by user.
     * <texObj> is the source texture object.
     * <texImage> is the source texture image.
     */
@@ -368,6 +364,9 @@ struct dd_function_table {
     * Example: if internalFormat==GL_COMPRESSED_RGB_FXT1_3DFX, return GL_RGB.
     */
 
+   GLint (*CompressedTextureSize)(GLcontext *ctx,
+                                  const struct gl_texture_image *texImage);
+
 #if 000
    /* ... Note the
     * return value differences between this function and
@@ -394,15 +393,6 @@ struct dd_function_table {
     * do the right thing with it.
     */
 
-   GLsizei (*CompressedImageSize)(GLcontext *ctx,
-                                  GLenum internalFormat,
-                                  GLuint numDimensions,
-                                  GLuint width,
-                                  GLuint height,
-                                  GLuint depth);
-   /* Calculate the size of a compressed image, given the image's
-    * format and dimensions.
-    */
 #endif
 
    /***
diff --git a/src/mesa/main/extensions.c b/src/mesa/main/extensions.c
index fc26efbb62f..169ae2d44ae 100644
--- a/src/mesa/main/extensions.c
+++ b/src/mesa/main/extensions.c
@@ -1,4 +1,4 @@
-/* $Id: extensions.c,v 1.61 2001/05/29 15:23:49 brianp Exp $ */
+/* $Id: extensions.c,v 1.62 2001/06/15 14:18:46 brianp Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -203,6 +203,34 @@ _mesa_enable_imaging_extensions(GLcontext *ctx)
 }
 
 
+
+/*
+ * Enable all OpenGL 1.3 features and extensions.
+ */
+void
+_mesa_enable_1_3_extensions(GLcontext *ctx)
+{
+   const char *extensions[] = {
+      "GL_ARB_multisample",
+      "GL_ARB_multitexture",
+      "GL_ARB_texture_border_clamp",
+      "GL_ARB_texture_compression",
+      "GL_ARB_texture_cube_map",
+      "GL_ARB_texture_env_add",
+      "GL_ARB_texture_env_combine",
+      "GL_ARB_texture_env_dot3",
+      "GL_ARB_transpose_matrix",
+      NULL
+   };
+   GLuint i;
+
+   for (i = 0; extensions[i]; i++) {
+      _mesa_enable_extension(ctx, extensions[i]);
+   }
+}
+
+
+
 /*
  * Add a new extenstion.  This would be called from a Mesa driver.
  */
diff --git a/src/mesa/main/extensions.h b/src/mesa/main/extensions.h
index c5015bf478f..bbf6debc79c 100644
--- a/src/mesa/main/extensions.h
+++ b/src/mesa/main/extensions.h
@@ -1,4 +1,4 @@
-/* $Id: extensions.h,v 1.13 2001/03/12 00:48:37 gareth Exp $ */
+/* $Id: extensions.h,v 1.14 2001/06/15 14:18:46 brianp Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -35,6 +35,8 @@ extern void _mesa_enable_sw_extensions(GLcontext *ctx);
 
 extern void _mesa_enable_imaging_extensions(GLcontext *ctx);
 
+extern void _mesa_enable_1_3_extensions(GLcontext *ctx);
+
 extern void _mesa_add_extension( GLcontext *ctx, GLboolean enabled,
                                  const char *name, GLboolean *flag_ptr );
 
diff --git a/src/mesa/main/state.c b/src/mesa/main/state.c
index 6b7682144dd..124770df3de 100644
--- a/src/mesa/main/state.c
+++ b/src/mesa/main/state.c
@@ -1,4 +1,4 @@
-/* $Id: state.c,v 1.66 2001/05/29 15:23:49 brianp Exp $ */
+/* $Id: state.c,v 1.67 2001/06/15 14:18:46 brianp Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -978,14 +978,16 @@ void _mesa_update_state( GLcontext *ctx )
    ASSERT(ctx->Driver.CopyTexSubImage2D);
    ASSERT(ctx->Driver.CopyTexSubImage3D);
    if (ctx->Extensions.ARB_texture_compression) {
+      ASSERT(ctx->Driver.BaseCompressedTexFormat);
+      ASSERT(ctx->Driver.CompressedTextureSize);
+      ASSERT(ctx->Driver.GetCompressedTexImage);
+#if 0  /* HW drivers need these, but not SW rasterizers */
       ASSERT(ctx->Driver.CompressedTexImage1D);
       ASSERT(ctx->Driver.CompressedTexImage2D);
       ASSERT(ctx->Driver.CompressedTexImage3D);
       ASSERT(ctx->Driver.CompressedTexSubImage1D);
       ASSERT(ctx->Driver.CompressedTexSubImage2D);
       ASSERT(ctx->Driver.CompressedTexSubImage3D);
-      ASSERT(ctx->Driver.IsCompressedFormat);
-      ASSERT(ctx->Driver.GetCompressedTexImage);
-      ASSERT(ctx->Driver.BaseCompressedTexFormat);
+#endif
    }
 }
diff --git a/src/mesa/main/texformat.c b/src/mesa/main/texformat.c
index d9ec9376ae1..b75a787862f 100644
--- a/src/mesa/main/texformat.c
+++ b/src/mesa/main/texformat.c
@@ -1,4 +1,4 @@
-/* $Id: texformat.c,v 1.10 2001/04/20 16:46:04 brianp Exp $ */
+/* $Id: texformat.c,v 1.11 2001/06/15 14:18:46 brianp Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -469,10 +469,11 @@ _mesa_is_hardware_tex_format( const struct gl_texture_format *format )
 }
 
 
-/* Given an internal texture format or 1, 2, 3, 4 initialize the texture
- * image structure's default format and type information.  Drivers will
- * initialize these fields accordingly if they override the default
- * storage format.
+/* Given an internal texture format (or 1, 2, 3, 4) return a pointer
+ * to a gl_texture_format which which to store the texture.
+ * This is called via ctx->Driver.ChooseTextureFormat().
+ * Hardware drivers should not use this function, but instead a 
+ * specialized function.
  */
 const struct gl_texture_format *
 _mesa_choose_tex_format( GLcontext *ctx, GLint internalFormat,
@@ -560,13 +561,89 @@ _mesa_choose_tex_format( GLcontext *ctx, GLint internalFormat,
    case GL_DEPTH_COMPONENT16_SGIX:
    case GL_DEPTH_COMPONENT24_SGIX:
    case GL_DEPTH_COMPONENT32_SGIX:
-      if ( !ctx->Extensions.SGIX_depth_texture )
-	 _mesa_problem( ctx, "depth format without GL_SGIX_depth_texture" );
+      if (!ctx->Extensions.SGIX_depth_texture)
+	 _mesa_problem(ctx, "depth format without GL_SGIX_depth_texture");
       return &_mesa_texformat_depth_component;
 
+   case GL_COMPRESSED_ALPHA_ARB:
+      if (!ctx->Extensions.ARB_texture_compression)
+	 _mesa_problem(ctx, "texture compression extension not enabled");
+      return &_mesa_texformat_alpha;
+   case GL_COMPRESSED_LUMINANCE_ARB:
+      if (!ctx->Extensions.ARB_texture_compression)
+	 _mesa_problem(ctx, "texture compression extension not enabled");
+      return &_mesa_texformat_luminance;
+   case GL_COMPRESSED_LUMINANCE_ALPHA_ARB:
+      if (!ctx->Extensions.ARB_texture_compression)
+	 _mesa_problem(ctx, "texture compression extension not enabled");
+      return &_mesa_texformat_luminance_alpha;
+   case GL_COMPRESSED_INTENSITY_ARB:
+      if (!ctx->Extensions.ARB_texture_compression)
+	 _mesa_problem(ctx, "texture compression extension not enabled");
+      return &_mesa_texformat_intensity;
+   case GL_COMPRESSED_RGB_ARB:
+      if (!ctx->Extensions.ARB_texture_compression)
+	 _mesa_problem(ctx, "texture compression extension not enabled");
+      return &_mesa_texformat_rgb;
+   case GL_COMPRESSED_RGBA_ARB:
+      if (!ctx->Extensions.ARB_texture_compression)
+	 _mesa_problem(ctx, "texture compression extension not enabled");
+      return &_mesa_texformat_rgba;
+
    default:
-      _mesa_problem( ctx, "unexpected format in _mesa_choose_tex_format()" );
-      printf("intformat = %d %x\n", internalFormat, internalFormat );
+      _mesa_problem(ctx, "unexpected format in _mesa_choose_tex_format()");
+      printf("intformat = %d %x\n", internalFormat, internalFormat);
       return NULL;
    }
 }
+
+
+
+
+/*
+ * Return the base texture format for the given compressed format
+ * Called via ctx->Driver.BaseCompressedTexFormat().
+ * This function is used by software rasterizers.  Hardware drivers
+ * which support texture compression should not use this function but
+ * a specialized function instead.
+ */
+GLint
+_mesa_base_compressed_texformat(GLcontext *ctx, GLint intFormat)
+{
+   switch (intFormat) {
+   case GL_COMPRESSED_ALPHA_ARB:
+      return GL_ALPHA;
+   case GL_COMPRESSED_LUMINANCE_ARB:
+      return GL_LUMINANCE;
+   case GL_COMPRESSED_LUMINANCE_ALPHA_ARB:
+      return GL_LUMINANCE_ALPHA;
+   case GL_COMPRESSED_INTENSITY_ARB:
+      return GL_INTENSITY;
+   case GL_COMPRESSED_RGB_ARB:
+      return GL_RGB;
+   case GL_COMPRESSED_RGBA_ARB:
+      return GL_RGBA;
+   default:
+      return -1;  /* not a recognized compressed format */
+   }
+}
+
+
+/*
+ * Called via ctx->Driver.CompressedTextureSize().
+ * This function is only used by software rasterizers.
+ * Hardware drivers will have to implement a specialized function.
+ */
+GLint
+_mesa_compressed_texture_size(GLcontext *ctx,
+                              const struct gl_texture_image *texImage)
+{
+   GLint b;
+   assert(texImage);
+   assert(texImage->TexFormat);
+
+   b = texImage->Width * texImage->Height * texImage->Depth *
+      texImage->TexFormat->TexelBytes;
+   assert(b > 0);
+   return b;
+}
diff --git a/src/mesa/main/texformat.h b/src/mesa/main/texformat.h
index ac6dbc0cb72..1360c9ee1c6 100644
--- a/src/mesa/main/texformat.h
+++ b/src/mesa/main/texformat.h
@@ -1,4 +1,4 @@
-/* $Id: texformat.h,v 1.6 2001/04/04 21:54:21 brianp Exp $ */
+/* $Id: texformat.h,v 1.7 2001/06/15 14:18:46 brianp Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -90,6 +90,13 @@ extern const struct gl_texture_format *
 _mesa_choose_tex_format( GLcontext *ctx, GLint internalFormat,
                          GLenum format, GLenum type );
 
+extern GLint
+_mesa_base_compressed_texformat(GLcontext *ctx, GLint intFormat);
+
+extern GLint
+_mesa_compressed_texture_size(GLcontext *ctx,
+                              const struct gl_texture_image *texImage);
+
 
 /* The default formats, GLchan per component:
  */
diff --git a/src/mesa/main/teximage.c b/src/mesa/main/teximage.c
index 0b535d1ecbd..eae4077c4ef 100644
--- a/src/mesa/main/teximage.c
+++ b/src/mesa/main/teximage.c
@@ -1,4 +1,4 @@
-/* $Id: teximage.c,v 1.97 2001/06/13 14:56:14 brianp Exp $ */
+/* $Id: teximage.c,v 1.98 2001/06/15 14:18:46 brianp Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -307,10 +307,14 @@ is_index_format(GLenum format)
 static GLboolean
 is_compressed_format(GLcontext *ctx, GLenum internalFormat)
 {
-    if (ctx->Driver.IsCompressedFormat) {
-        return (*ctx->Driver.IsCompressedFormat)(ctx, internalFormat);
-    }
-    return GL_FALSE;
+   if (ctx->Driver.BaseCompressedTexFormat) {
+      GLint b = (*ctx->Driver.BaseCompressedTexFormat)(ctx, internalFormat);
+      if (b > 0)
+         return GL_TRUE;
+      else
+         return GL_FALSE;
+   }
+   return GL_FALSE;
 }
 
 
@@ -593,6 +597,7 @@ _mesa_init_teximage_fields(GLcontext *ctx,
 {
    ASSERT(img);
    img->Format = _mesa_base_tex_format( ctx, internalFormat );
+   ASSERT(img->Format > 0);
    img->IntFormat = internalFormat;
    img->Border = border;
    img->Width = width;
@@ -761,6 +766,8 @@ texture_error_check( GLcontext *ctx, GLenum target,
       return GL_TRUE;
    }
 
+   ASSERT(iformat > 0);
+
    if (!is_compressed_format( ctx, internalFormat ) &&
        !_mesa_is_legal_format_and_type( format, type )) {
       /* Yes, generate GL_INVALID_OPERATION, not GL_INVALID_ENUM, if there
@@ -796,6 +803,7 @@ subtexture_error_check( GLcontext *ctx, GLuint dimensions,
    struct gl_texture_unit *texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
    struct gl_texture_image *destTex;
    GLint maxLevels = 0;
+   GLboolean compressed;
 
    if (dimensions == 1) {
       if (target != GL_TEXTURE_1D) {
@@ -898,14 +906,33 @@ subtexture_error_check( GLcontext *ctx, GLuint dimensions,
       }
    }
 
-   if (!is_compressed_format(ctx, destTex->IntFormat) &&
-       !_mesa_is_legal_format_and_type(format, type)) {
+   compressed = is_compressed_format(ctx, destTex->IntFormat);
+
+   if (!compressed && !_mesa_is_legal_format_and_type(format, type)) {
       char message[100];
       sprintf(message, "glTexSubImage%dD(format or type)", dimensions);
       _mesa_error(ctx, GL_INVALID_ENUM, message);
       return GL_TRUE;
    }
 
+   if (compressed) {
+      if (xoffset != -destTex->Border) {
+         _mesa_error(ctx, GL_INVALID_OPERATION,
+                     "glTexSubImage1/2/3D(xoffset != -border");
+         return GL_TRUE;
+      }
+      if (dimensions > 1 && yoffset != -destTex->Border) {
+         _mesa_error(ctx, GL_INVALID_OPERATION,
+                     "glTexSubImage2/3D(yoffset != -border");
+         return GL_TRUE;
+      }
+      if (dimensions > 2 && zoffset != -destTex->Border) {
+         _mesa_error(ctx, GL_INVALID_OPERATION,
+                     "glTexSubImage3D(zoffset != -border");
+         return GL_TRUE;
+      }
+   }
+
    return GL_FALSE;
 }
 
@@ -1019,6 +1046,7 @@ copytexsubimage_error_check( GLcontext *ctx, GLuint dimensions,
    struct gl_texture_unit *texUnit = &ctx->Texture.Unit[ctx->Texture.CurrentUnit];
    struct gl_texture_image *teximage;
    GLint maxLevels = 0;
+   GLboolean compressed;
 
    if (dimensions == 1) {
       if (target != GL_TEXTURE_1D) {
@@ -1126,6 +1154,25 @@ copytexsubimage_error_check( GLcontext *ctx, GLuint dimensions,
       }
    }
 
+   compressed = is_compressed_format(ctx, teximage->IntFormat);
+   if (compressed) {
+      if (xoffset != -teximage->Border) {
+         _mesa_error(ctx, GL_INVALID_OPERATION,
+                     "glCopyTexSubImage1/2/3D(xoffset != -border");
+         return GL_TRUE;
+      }
+      if (dimensions > 1 && yoffset != -teximage->Border) {
+         _mesa_error(ctx, GL_INVALID_OPERATION,
+                     "glCopyTexSubImage2/3D(yoffset != -border");
+         return GL_TRUE;
+      }
+      if (dimensions > 2 && zoffset != -teximage->Border) {
+         _mesa_error(ctx, GL_INVALID_OPERATION,
+                     "glCopyTexSubImage3D(zoffset != -border");
+         return GL_TRUE;
+      }
+   }
+
    /* if we get here, the parameters are OK */
    return GL_FALSE;
 }
@@ -1329,6 +1376,10 @@ _mesa_TexImage1D( GLenum target, GLint level, GLint internalFormat,
       }
       ASSERT(texImage->FetchTexel);
 
+      if (texImage->IsCompressed) {
+         ASSERT(texImage->CompressedSize > 0);
+      }
+
       /* state update */
       texObj->Complete = GL_FALSE;
       ctx->NewState |= _NEW_TEXTURE;
@@ -1442,6 +1493,10 @@ _mesa_TexImage2D( GLenum target, GLint level, GLint internalFormat,
       }
       ASSERT(texImage->FetchTexel);
 
+      if (texImage->IsCompressed) {
+         ASSERT(texImage->CompressedSize > 0);
+      }
+
       /* state update */
       texObj->Complete = GL_FALSE;
       ctx->NewState |= _NEW_TEXTURE;
@@ -1551,6 +1606,10 @@ _mesa_TexImage3D( GLenum target, GLint level, GLenum internalFormat,
       }
       ASSERT(texImage->FetchTexel);
 
+      if (texImage->IsCompressed) {
+         ASSERT(texImage->CompressedSize > 0);
+      }
+
       /* state update */
       texObj->Complete = GL_FALSE;
       ctx->NewState |= _NEW_TEXTURE;
@@ -2416,7 +2475,7 @@ _mesa_GetCompressedTexImageARB(GLenum target, GLint level, GLvoid *img)
 
    texImage = _mesa_select_tex_image(ctx, texUnit, target, level);
    if (!texImage) {
-      /* invalid mipmap level */
+      /* probably invalid mipmap level */
       _mesa_error(ctx, GL_INVALID_VALUE, "glGetCompressedTexImageARB(level)");
       return;
    }
diff --git a/src/mesa/main/texstore.c b/src/mesa/main/texstore.c
index 792f58bb975..19eb36e6f07 100644
--- a/src/mesa/main/texstore.c
+++ b/src/mesa/main/texstore.c
@@ -1,4 +1,4 @@
-/* $Id: texstore.c,v 1.28 2001/06/13 14:56:14 brianp Exp $ */
+/* $Id: texstore.c,v 1.29 2001/06/15 14:18:46 brianp Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -416,6 +416,8 @@ _mesa_transfer_teximage(GLcontext *ctx, GLuint dimensions,
    GLboolean freeSourceData = GL_FALSE;
    GLint postConvWidth = srcWidth, postConvHeight = srcHeight;
 
+   assert(baseInternalFormat > 0);
+
    if (transferOps & IMAGE_CONVOLUTION_BIT) {
       _mesa_adjust_image_for_convolution(ctx, dimensions, &postConvWidth,
                                          &postConvHeight);
@@ -614,7 +616,7 @@ _mesa_store_teximage1d(GLcontext *ctx, GLenum target, GLint level,
                        struct gl_texture_image *texImage)
 {
    GLint postConvWidth = width;
-   GLint texelBytes;
+   GLint texelBytes, sizeInBytes;
 
    if (ctx->_ImageTransferState & IMAGE_CONVOLUTION_BIT) {
       _mesa_adjust_image_for_convolution(ctx, 1, &postConvWidth, NULL);
@@ -629,8 +631,19 @@ _mesa_store_teximage1d(GLcontext *ctx, GLenum target, GLint level,
 
    texelBytes = texImage->TexFormat->TexelBytes;
 
+   /* Compute image size, in bytes */
+   if (texImage->IsCompressed) {
+      assert(ctx->Driver.CompressedTextureSize);
+      sizeInBytes = ctx->Driver.CompressedTextureSize(ctx, texImage);
+      assert(sizeInBytes > 0);
+      texImage->CompressedSize = sizeInBytes;
+   }
+   else {
+      sizeInBytes = postConvWidth * texelBytes;
+   }
+
    /* allocate memory */
-   texImage->Data = MALLOC(postConvWidth * texelBytes);
+   texImage->Data = MALLOC(sizeInBytes);
    if (!texImage->Data) {
       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glTexImage1D");
       return;
@@ -658,6 +671,8 @@ _mesa_store_teximage1d(GLcontext *ctx, GLenum target, GLint level,
  * The texture image format will be GL_COLOR_INDEX, GL_INTENSITY,
  * GL_LUMINANCE, GL_LUMINANCE_ALPHA, GL_ALPHA, GL_RGB or GL_RGBA.
  *
+ * NOTE: if real texture compression is supported, this whole function
+ * will need to be overridden.
  */
 void
 _mesa_store_teximage2d(GLcontext *ctx, GLenum target, GLint level,
@@ -669,7 +684,7 @@ _mesa_store_teximage2d(GLcontext *ctx, GLenum target, GLint level,
                        struct gl_texture_image *texImage)
 {
    GLint postConvWidth = width, postConvHeight = height;
-   GLint texelBytes;
+   GLint texelBytes, sizeInBytes;
 
    if (ctx->_ImageTransferState & IMAGE_CONVOLUTION_BIT) {
       _mesa_adjust_image_for_convolution(ctx, 2, &postConvWidth,
@@ -685,8 +700,19 @@ _mesa_store_teximage2d(GLcontext *ctx, GLenum target, GLint level,
 
    texelBytes = texImage->TexFormat->TexelBytes;
 
+   /* Compute image size, in bytes */
+   if (texImage->IsCompressed) {
+      assert(ctx->Driver.CompressedTextureSize);
+      sizeInBytes = ctx->Driver.CompressedTextureSize(ctx, texImage);
+      assert(sizeInBytes > 0);
+      texImage->CompressedSize = sizeInBytes;
+   }
+   else {
+      sizeInBytes = postConvWidth * postConvHeight * texelBytes;
+   }
+
    /* allocate memory */
-   texImage->Data = MALLOC(postConvWidth * postConvHeight * texelBytes);
+   texImage->Data = MALLOC(sizeInBytes);
    if (!texImage->Data) {
       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glTexImage2D");
       return;
@@ -725,7 +751,7 @@ _mesa_store_teximage3d(GLcontext *ctx, GLenum target, GLint level,
                        struct gl_texture_object *texObj,
                        struct gl_texture_image *texImage)
 {
-   GLint texelBytes;
+   GLint texelBytes, sizeInBytes;
 
    /* choose the texture format */
    assert(ctx->Driver.ChooseTextureFormat);
@@ -736,8 +762,19 @@ _mesa_store_teximage3d(GLcontext *ctx, GLenum target, GLint level,
 
    texelBytes = texImage->TexFormat->TexelBytes;
 
+   /* Compute image size, in bytes */
+   if (texImage->IsCompressed) {
+      assert(ctx->Driver.CompressedTextureSize);
+      sizeInBytes = ctx->Driver.CompressedTextureSize(ctx, texImage);
+      assert(sizeInBytes > 0);
+      texImage->CompressedSize = sizeInBytes;
+   }
+   else {
+      sizeInBytes = width * height * depth * texelBytes;
+   }
+
    /* allocate memory */
-   texImage->Data = MALLOC(width * height * depth * texelBytes);
+   texImage->Data = MALLOC(sizeInBytes);
    if (!texImage->Data) {
       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glTexImage3D");
       return;
@@ -905,6 +942,25 @@ _mesa_store_compressed_teximage3d(GLcontext *ctx, GLenum target, GLint level,
 
 
 /*
+ * Fallback for Driver.GetCompressedTexImage3D()
+ * This will probably work find for hardware drivers.  That is, hardware
+ * drivers won't have to override this function, unless the compressed
+ * texture must first be fetched from the TRAM.
+ */
+void
+_mesa_get_compressed_teximage(GLcontext *ctx, GLenum target,
+                              GLint level, void *image,
+                              const struct gl_texture_object *texObj,
+                              struct gl_texture_image *texImage)
+{
+   assert(texImage->IsCompressed);
+   assert(texImage->CompressedSize > 0);
+   MEMCPY(image, texImage->Data, texImage->CompressedSize);
+}
+
+
+
+/*
  * This is the fallback for Driver.TestProxyTexImage().
  */
 GLboolean
diff --git a/src/mesa/main/texstore.h b/src/mesa/main/texstore.h
index 4d62a015f03..bde79090185 100644
--- a/src/mesa/main/texstore.h
+++ b/src/mesa/main/texstore.h
@@ -1,4 +1,4 @@
-/* $Id: texstore.h,v 1.8 2001/05/21 16:41:04 brianp Exp $ */
+/* $Id: texstore.h,v 1.9 2001/06/15 14:18:46 brianp Exp $ */
 
 /*
  * Mesa 3-D graphics library
@@ -135,6 +135,13 @@ _mesa_store_compressed_teximage3d(GLcontext *ctx, GLenum target, GLint level,
                                   struct gl_texture_image *texImage);
 
 
+extern void
+_mesa_get_compressed_teximage(GLcontext *ctx, GLenum target,
+                              GLint level, void *image,
+                              const struct gl_texture_object *texObj,
+                              struct gl_texture_image *texImage);
+
+
 extern GLboolean
 _mesa_test_proxy_teximage(GLcontext *ctx, GLenum target, GLint level,
                          GLint internalFormat, GLenum format, GLenum type,