On Fri, Aug 17, 2012 at 8:28 PM, Ian Romanick <i...@freedesktop.org> wrote: > On 08/16/2012 02:29 PM, Anuj Phogat wrote: >> >> On Thu, Aug 16, 2012 at 10:23 AM, Brian Paul <bri...@vmware.com> wrote: >>> >>> On 08/15/2012 02:31 PM, Anuj Phogat wrote: >>>> >>>> >>>> On Tue, May 1, 2012 at 2:07 PM, Brian Paul <bri...@vmware.com >>>> <mailto:bri...@vmware.com>> wrote: >>>> >>>> When glTexImage or glCopyTexImage is called with internalFormat >>>> being a >>>> generic compressed format (like GL_COMPRESSED_RGB) we need to do >>>> the same >>>> error checks as for specific compressed formats. In particular, >>>> check if >>>> the texture target is compatible with the format. None of the >>>> texture >>>> compression formats we support so far work with GL_TEXTURE_1D, for >>>> example. >>>> >>>> See also https://bugs.freedesktop.org/show_bug.cgi?id=49124 >>>> >>>> >>>> Brian, generic texture compression formats with GL_TEXTURE_1D seem to >>>> work fine >>>> on i965 drivers. >>> >>> >>> Does that wind up using one of the DXT formats? >> >> It uses RGTC for GL_COMPRESSED_RED & GL_COMPRESSED_RG >> FXT for GL_COMPRESSED_RGB & GL_COMPRESSED_RGBA > > > I wonder if that produces correct results. There are lots of limitations > with those formats... > I noticed failures in case of GL_TEXTURE_3D with GL_COMPRESSED_RGBA format. Failures disappeared when I made changes to pick an uncompressed format. >>> I verified this by allowing generic texture >>>> >>>> >>>> compression formats for >>>> GL_TEXTURE_1D in piglit copyteximage test case and reverting the >>>> changes due to >>>> this patch on mesa. Is this an issue only on swrast? >>> >>> >>> >>> That's what the bug reported, don't recall testing other drivers. >>> >>> >>> >>>> Returning >>>> GL_INVALID_ENUM >>>> error for generic texture compression formats in glTexImage1D() and >>>> glCopyTexImage1D() doesn't seem to follow the OpenGL >>>> specification. Spec does allow >>>> GL_INVALID_ENUM error for a similar scenario in case >>>> of glCompressedTexImage1D(). >>>> Please correct me if I'm missing something. >>> >>> >>> >>> I guess I'd like to check what either NVIDIA or AMD do in some of these >>> cases. >>> >>> AFAIK, the various DXT, LATC, etc compressed formats are only spec'd to >>> work >>> with 2D textures, not 1D. Since 1D textures are generally pretty small >>> to >>> start with, there's not a lot of value in compressed 1D textures. Plus, >>> if >>> a compressed 1D texture uses 4 or 8 bytes to store a 4x1 block of texels, >>> there's only 50% or 0% memory savings with compression. > > > Most of the specific formats are specified to only work with 2D textures. > > From EXT_texture_compression_s3tc (note that 1D variants of TexImage, > CopyTexImage, etc are missing): > > Accepted by the <internalformat> parameter of TexImage2D, > CopyTexImage2D, > and CompressedTexImage2DARB and the <format> parameter of > CompressedTexSubImage2DARB: > > COMPRESSED_RGB_S3TC_DXT1_EXT 0x83F0 > COMPRESSED_RGBA_S3TC_DXT1_EXT 0x83F1 > COMPRESSED_RGBA_S3TC_DXT3_EXT 0x83F2 > COMPRESSED_RGBA_S3TC_DXT5_EXT 0x83F3 > > Same for 3DFX_texture_compression_FXT1: > > Accepted by the <internalformat> parameter of TexImage2D, > CopyTexImage2D, TexImage3D, CopyTexImage3D, and by the > <internalformat> and <format> parameters of > CompressedTexImage2D_ARB, CompressedTexSubImage2D_ARB, > CompressedTexImage3D_ARB, CompressedTexSubImage3D_ARB: > > COMPRESSED_RGB_FXT1_3DFX 0x86B0 > COMPRESSED_RGBA_FXT1_3DFX 0x86B1 > > However, the generic formats should be accepted. From > ARB_texture_compression: > > Accepted by the <internalformat> parameter of TexImage1D, TexImage2D, > TexImage3D, CopyTexImage1D, and CopyTexImage2D: > > COMPRESSED_ALPHA_ARB 0x84E9 > COMPRESSED_LUMINANCE_ARB 0x84EA > COMPRESSED_LUMINANCE_ALPHA_ARB 0x84EB > COMPRESSED_INTENSITY_ARB 0x84EC > COMPRESSED_RGB_ARB 0x84ED > COMPRESSED_RGBA_ARB 0x84EE > > When the application specifies a generic format, the driver is always free > to pick an uncompressed format. Many Mesa drivers (primarily the ones we > removed a couple years ago) have done that for ages. :) > ok. I will make changes to allow these formats for 1D/3D textures as well and and pick a matching uncompressed format internally. Do we need any special treatment for 2D textures? I mean picking a matching compressed format as they are well supported on 2D targets.
>>> If you can post your patch for the piglit test I can run it with the >>> NVIDIA >>> driver and see what it does. >> >> I'll send out a follow up patch for piglit test case which you can use >> for testing. >> >>> >>> -Brian >> >> _______________________________________________ >> >> mesa-dev mailing list >> mesa-dev@lists.freedesktop.org >> http://lists.freedesktop.org/mailman/listinfo/mesa-dev _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
