Add Roland Scheidegger's S3TC patch. This patch does not implement the

(patented) S3TC/DXTC algorithms, but adds an option to dlopen a library module
providing functions to do so.  Because it uses dlopen, it is only enabled if
USE_EXTERNAL_DXTN_LIB=1 is defined (which is only in linux-dri config, so far).
It adds support for S3TC to several DRI drivers, and adds a DRI config option to
force enabling S3TC even if the software compression/decompression is
unavailable.  This may allow people to use apps that require S3TC even though
they don't have a license to implement the patented material themselves, if
those apps use precompressed textures.

Ideally we would get permission from the current holder of the patents to
implement the algorithm in Mesa, at which point the dlopen mess could go away.
Until then, this allows some to run applications they couldn't otherwise, and
hopefully will provide us with more push to get the final step of getting that
permission done.

1 files changed, 129 insertions, 0 deletions

diff --git a/src/mesa/drivers/dri/r200/r200_tex.c b/src/mesa/drivers/dri/r200/r200_tex.c
index 346c27cee0..3d259c2ca6 100644
--- a/src/mesa/drivers/dri/r200/r200_tex.c
+++ b/src/mesa/drivers/dri/r200/r200_tex.c
@@ -420,6 +420,22 @@ r200ChooseTextureFormat( GLcontext *ctx, GLint internalFormat,
       else
          return &_mesa_texformat_ycbcr_rev;
 
+   case GL_RGB_S3TC:
+   case GL_RGB4_S3TC:
+   case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
+      return &_mesa_texformat_rgb_dxt1;
+
+   case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
+      return &_mesa_texformat_rgba_dxt1;
+
+   case GL_RGBA_S3TC:
+   case GL_RGBA4_S3TC:
+   case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
+      return &_mesa_texformat_rgba_dxt3;
+
+   case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
+      return &_mesa_texformat_rgba_dxt5;
+
    default:
       _mesa_problem(ctx,
          "unexpected internalFormat 0x%x in r200ChooseTextureFormat",
@@ -710,6 +726,116 @@ static void r200TexSubImage2D( GLcontext *ctx, GLenum target, GLint level,
 }
 
 
+static void r200CompressedTexImage2D( GLcontext *ctx, GLenum target, GLint level,
+                              GLint internalFormat,
+                              GLint width, GLint height, GLint border,
+                              GLsizei imageSize, const GLvoid *data,
+                              struct gl_texture_object *texObj,
+                              struct gl_texture_image *texImage )
+{
+   driTextureObject * t = (driTextureObject *) texObj->DriverData;
+   GLuint face;
+
+   /* which cube face or ordinary 2D image */
+   switch (target) {
+   case GL_TEXTURE_CUBE_MAP_POSITIVE_X:
+   case GL_TEXTURE_CUBE_MAP_NEGATIVE_X:
+   case GL_TEXTURE_CUBE_MAP_POSITIVE_Y:
+   case GL_TEXTURE_CUBE_MAP_NEGATIVE_Y:
+   case GL_TEXTURE_CUBE_MAP_POSITIVE_Z:
+   case GL_TEXTURE_CUBE_MAP_NEGATIVE_Z:
+      face = (GLuint) target - (GLuint) GL_TEXTURE_CUBE_MAP_POSITIVE_X;
+      ASSERT(face < 6);
+      break;
+   default:
+      face = 0;
+   }
+
+   if ( t != NULL ) {
+      driSwapOutTextureObject( t );
+   }
+   else {
+      t = (driTextureObject *) r200AllocTexObj( texObj );
+      if (!t) {
+         _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCompressedTexImage2D");
+         return;
+      }
+   }
+
+   texImage->IsClientData = GL_FALSE;
+/* can't call this, different parameters. Would never evaluate to true anyway currently
+   if (r200ValidateClientStorage( ctx, target, 
+				  internalFormat,
+				  width, height,
+				  format, type, pixels,
+				  packing, texObj, texImage)) {
+      if (R200_DEBUG & DEBUG_TEXTURE)
+	 fprintf(stderr, "%s: Using client storage\n", __FUNCTION__);
+   }
+   else */{
+      if (R200_DEBUG & DEBUG_TEXTURE)
+	 fprintf(stderr, "%s: Using normal storage\n", __FUNCTION__);
+
+      /* Normal path: copy (to cached memory) and eventually upload
+       * via another copy to GART memory and then a blit...  Could
+       * eliminate one copy by going straight to (permanent) GART.
+       *
+       * Note, this will call r200ChooseTextureFormat.
+       */
+      _mesa_store_compressed_teximage2d(ctx, target, level, internalFormat, width,
+                                 height, border, imageSize, data, texObj, texImage);
+
+      t->dirty_images[face] |= (1 << level);
+   }
+}
+
+
+static void r200CompressedTexSubImage2D( GLcontext *ctx, GLenum target, GLint level,
+                                 GLint xoffset, GLint yoffset,
+                                 GLsizei width, GLsizei height,
+                                 GLenum format,
+                                 GLsizei imageSize, const GLvoid *data,
+                                 struct gl_texture_object *texObj,
+                                 struct gl_texture_image *texImage )
+{
+   driTextureObject * t = (driTextureObject *) texObj->DriverData;
+   GLuint face;
+
+
+   /* which cube face or ordinary 2D image */
+   switch (target) {
+   case GL_TEXTURE_CUBE_MAP_POSITIVE_X:
+   case GL_TEXTURE_CUBE_MAP_NEGATIVE_X:
+   case GL_TEXTURE_CUBE_MAP_POSITIVE_Y:
+   case GL_TEXTURE_CUBE_MAP_NEGATIVE_Y:
+   case GL_TEXTURE_CUBE_MAP_POSITIVE_Z:
+   case GL_TEXTURE_CUBE_MAP_NEGATIVE_Z:
+      face = (GLuint) target - (GLuint) GL_TEXTURE_CUBE_MAP_POSITIVE_X;
+      ASSERT(face < 6);
+      break;
+   default:
+      face = 0;
+   }
+
+   assert( t ); /* this _should_ be true */
+   if ( t ) {
+      driSwapOutTextureObject( t );
+   }
+   else {
+      t = (driTextureObject *) r200AllocTexObj( texObj );
+      if (!t) {
+         _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCompressedTexSubImage2D");
+         return;
+      }
+   }
+
+   _mesa_store_compressed_texsubimage2d(ctx, target, level, xoffset, yoffset, width,
+                            height, format, imageSize, data, texObj, texImage);
+
+   t->dirty_images[face] |= (1 << level);
+}
+
+
 #if ENABLE_HW_3D_TEXTURE
 static void r200TexImage3D( GLcontext *ctx, GLenum target, GLint level,
                             GLint internalFormat,
@@ -1036,6 +1162,9 @@ void r200InitTextureFuncs( struct dd_function_table *functions )
    functions->TexParameter		= r200TexParameter;
    functions->TexGen			= r200TexGen;
 
+   functions->CompressedTexImage2D	= r200CompressedTexImage2D;
+   functions->CompressedTexSubImage2D	= r200CompressedTexSubImage2D;
+
    driInitTextureFormats();
 
 #if 000