On Mon, Sep 10, 2012 at 6:35 PM, Brian Paul <brian.e.p...@gmail.com> wrote: > On Mon, Sep 10, 2012 at 3:16 PM, Anuj Phogat <anuj.pho...@gmail.com> wrote: >> On Thu, Mar 8, 2012 at 7:19 PM, Brian Paul <bri...@vmware.com> wrote: >>> There are several cases in which we need to explicity "rebase" colors >>> (ex: set G=B=0) when getting GL_LUMINANCE textures: >>> 1. If the luminance texture is actually stored as rgba >>> 2. If getting a luminance texture, but returning rgba >>> 3. If getting an rgba texture, but returning luminance >>> >>> Fixes https://bugs.freedesktop.org/show_bug.cgi?id=46679 >>> >>> Also fixes the new piglit getteximage-luminance test. >>> --- >>> src/mesa/main/texgetimage.c | 30 ++++++++++++++++++++++++++++-- >>> 1 files changed, 28 insertions(+), 2 deletions(-) >>> >>> diff --git a/src/mesa/main/texgetimage.c b/src/mesa/main/texgetimage.c >>> index 44a828a..05b052a 100644 >>> --- a/src/mesa/main/texgetimage.c >>> +++ b/src/mesa/main/texgetimage.c >>> @@ -298,6 +298,8 @@ get_tex_rgba_uncompressed(struct gl_context *ctx, >>> GLuint dimensions, >>> const gl_format texFormat = >>> _mesa_get_srgb_format_linear(texImage->TexFormat); >>> const GLuint width = texImage->Width; >>> + const GLenum destBaseFormat = _mesa_base_tex_format(ctx, format); >>> + GLenum rebaseFormat = GL_NONE; >>> GLuint height = texImage->Height; >>> GLuint depth = texImage->Depth; >>> GLuint img, row; >>> @@ -318,6 +320,28 @@ get_tex_rgba_uncompressed(struct gl_context *ctx, >>> GLuint dimensions, >>> height = 1; >>> } >>> >>> + if (texImage->_BaseFormat == GL_LUMINANCE || >>> + texImage->_BaseFormat == GL_INTENSITY || >>> + texImage->_BaseFormat == GL_LUMINANCE_ALPHA) { >>> + /* If a luminance (or intensity) texture is read back as RGB(A), the >>> + * returned value should be (L,0,0,1), not (L,L,L,1). Set >>> rebaseFormat >>> + * here to get G=B=0. >>> + */ >>> + rebaseFormat = texImage->_BaseFormat; >>> + } >>> + else if ((texImage->_BaseFormat == GL_RGBA || >>> + texImage->_BaseFormat == GL_RGB) && >>> + (destBaseFormat == GL_LUMINANCE || >>> + destBaseFormat == GL_LUMINANCE_ALPHA || >>> + destBaseFormat == GL_LUMINANCE_INTEGER_EXT || >>> + destBaseFormat == GL_LUMINANCE_ALPHA_INTEGER_EXT)) { >>> + /* If we're reading back an RGB(A) texture as luminance then we need >>> + * to return L=tex(R). Note, that's different from glReadPixels >>> which >>> + * returns L=R+G+B. >>> + */ >> Brian, don't we need do handle the similar case for compressed textures? >> i.e. _mesa_meta_GetTexImage()->decompress_texture_image() currently >> uses _mesa_ReadPixels() to get the compressed texture data, which >> returns L=R+G+B. I haven't yet tested how NVIDIA/AMD handle compressed >> textures in glGetTexImage(). > > That's probably correct. Can you take care of that? > > -Brian
Yeah, I verified this on NVIDIA and AMD's proprietary linux drivers. I'll soon post a patch to fix this. _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
