Re: [Mesa-dev] EXT_tetxure_swizzle and BGRA textures : glean test enhancement
On 02.05.2010 13:08, José Fonseca wrote: On Sun, 2010-05-02 at 02:36 -0700, Dave Airlie wrote: On Sun, May 2, 2010 at 7:30 PM, Jose Fonseca jfons...@vmware.com wrote: I read the extension and it is not crystal clear, but it seems to imply the swizzles are orthogonal to the format, and applied as the very last step before being used in a shader. That is, the semantics are the same of adding a swizzle instruction after a TEX opcode, regardless of the format. At least this is my interpretation of The values of the texture parameters TEXTURE_SWIZZLE_R_EXT, TEXTURE_SWIZZLE_G_EXT, TEXTURE_SWIZZLE_B_EXT, and TEXTURE_SWIZZLE_A_EXT, are applied after the swizzling described in Table 3.20 (p. 186). The swizzle parameter TEXTURE_SWIZZLE_R_EXT affects the first component of Cs as: BGRA extension does not specify additions to the 3.20 table though (it's against spec 1.1) so this is why the guess work. So my expectaction is that swizzling a BGRA with a .rgba swizzle will get bgra. It is also interesting the mention that the swizzle happens after texture compare mode. Actually, I mistyped, it is not texture compare mode, just depth texture mode. Yeah, this is all a bit confusing, but the depth texture comparison, if enabled, always uses the depth value from the texture, as you'd expect. This value then gets assigned to rgba/rgb/a depending on depth texture mode. So the texture swizzle happens after that - of course that means if you have specified a swizzle of . but your depth texture mode was alpha, you'll get a nice .... That is my interpretation as well, so in the r300 hw for example we use the texture swizzle to implement bgra vs rgba formats, I'd need to combine that with the incoming GL swizzle from the extension, but I'd really like to have some sort of test case to demonstrate it as I'm really not sure how ugly the combine swizzles function might end up. But it looks as if I need to write a direct to gallium test case to make sure I'm actually using things, mesa seems to block my attempts, though maybe with something like a PBO I can make mesa do it. I see now. It's probably worth to fix Mesa to memcpy user data unmodified as much as possible. grepping for GL_BGRA and PIPE_FORMAT_B8G8R8A8 in mesa shows some inconsistencies. Even for PBOs we say that PIPE_FORMAT_B8G8R8A8 is GL_RGBA and not GL_BGRA. A good way to go about this is centralize Gallium - GL and Gallium - Mesa format information in a big table. It means whenever a new format is added, there are a few places to modify. Anwyay this cleanup is not urgent, and is likely to cause regressions. FWIW, there's not only interaction with textures with different ordering (like bgra) but also those which are defined as rgb1 for instance. If you specify a swizzle of .aarr for instance, of course you'll get .11rr effectively. Roland ___ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
Re: [Mesa-dev] EXT_tetxure_swizzle and BGRA textures : glean test enhancement
Jose Fonseca wrote: I read the extension and it is not crystal clear, but it seems to imply the swizzles are orthogonal to the format, and applied as the very last step before being used in a shader. That is, the semantics are the same of adding a swizzle instruction after a TEX opcode, regardless of the format. At least this is my interpretation of The values of the texture parameters TEXTURE_SWIZZLE_R_EXT, TEXTURE_SWIZZLE_G_EXT, TEXTURE_SWIZZLE_B_EXT, and TEXTURE_SWIZZLE_A_EXT, are applied after the swizzling described in Table 3.20 (p. 186). The swizzle parameter TEXTURE_SWIZZLE_R_EXT affects the first component of Cs as: Correct. BGRA extension does not specify additions to the 3.20 table though (it's against spec 1.1) so this is why the guess work. So my expectaction is that swizzling a BGRA with a .rgba swizzle will get bgra. Mmm, I don't think so. Regardless of the original user texture component ordering and regardless of the actually hardware texture format, when the shader calls texture2D(sampler, coord), for example, it _always_ returns a vector of (R, G, B, A) in that order. Similarly for ARB_vp/fp and fixed-function texture sampling. We'd have a miserable time writing shaders if we texture2D(sampler, coord) returned different component orderings depending on the actual texture format (which could vary from one system to another). An extenstion like GL_EXT_bgra is used to describe the incoming/user texture data to glTexImage2D, nothing about the internal/actual texture layout. -Brian ___ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
Re: [Mesa-dev] EXT_tetxure_swizzle and BGRA textures : glean test enhancement
Dave Airlie wrote: In looking at adding EXT_texture_swizzle I'm a bit confused about what exactly should happen with BGRA textures, as on r300 we use the texture swizzling to do BGRA, so we would have some interaction at that point. To make sure we test for this I've made the following enhancments to the glean test (in piglit tree - but I'll resubmit against glean tree if correct). Can someone with a clue make sure this is a sane test, it passes against swrast.. The patch is sane. You're basically just defining the user texture either in RGBA vs. BGRA order in the two cases. This has no bearing on the internal/actual format of the texture or the results of sampling from the texture. However, I suggest: 1. use a better name for the 'format_pick' variable 2. add a comment for that parameter. 3. it's used as a boolean, so s/int/bool/ 4. fix up the indentation to match the rest of the file. -Brian ___ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
Re: [Mesa-dev] EXT_tetxure_swizzle and BGRA textures : glean test enhancement
On Mon, 2010-05-03 at 09:44 -0700, Brian Paul wrote: Jose Fonseca wrote: I read the extension and it is not crystal clear, but it seems to imply the swizzles are orthogonal to the format, and applied as the very last step before being used in a shader. That is, the semantics are the same of adding a swizzle instruction after a TEX opcode, regardless of the format. At least this is my interpretation of The values of the texture parameters TEXTURE_SWIZZLE_R_EXT, TEXTURE_SWIZZLE_G_EXT, TEXTURE_SWIZZLE_B_EXT, and TEXTURE_SWIZZLE_A_EXT, are applied after the swizzling described in Table 3.20 (p. 186). The swizzle parameter TEXTURE_SWIZZLE_R_EXT affects the first component of Cs as: Correct. BGRA extension does not specify additions to the 3.20 table though (it's against spec 1.1) so this is why the guess work. So my expectaction is that swizzling a BGRA with a .rgba swizzle will get bgra. Mmm, I don't think so. Regardless of the original user texture component ordering and regardless of the actually hardware texture format, when the shader calls texture2D(sampler, coord), for example, it _always_ returns a vector of (R, G, B, A) in that order. Similarly for ARB_vp/fp and fixed-function texture sampling. We'd have a miserable time writing shaders if we texture2D(sampler, coord) returned different component orderings depending on the actual texture format (which could vary from one system to another). Actually, this is what I meant, but I see now I explained miserably! (@_@) What I meant is that if the user specifies a BGRA texture with the _bytes_: X Y Z W and we specify the TEXTURE_SWIZZLEs as (R, G, B, A) then we'd obtain W Z W X. in the shader (normalized by 1/255). What I mean is that the format swizzles have to be composed with the shader swizzles. An extenstion like GL_EXT_bgra is used to describe the incoming/user texture data to glTexImage2D, nothing about the internal/actual texture layout. Yes. Jose ___ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
Re: [Mesa-dev] EXT_tetxure_swizzle and BGRA textures : glean test enhancement
Dave Airlie wrote: On Sat, May 1, 2010 at 6:47 PM, Dave Airlie airl...@gmail.com wrote: In looking at adding EXT_texture_swizzle I'm a bit confused about what exactly should happen with BGRA textures, as on r300 we use the texture swizzling to do BGRA, so we would have some interaction at that point. To make sure we test for this I've made the following enhancments to the glean test (in piglit tree - but I'll resubmit against glean tree if correct). Can someone with a clue make sure this is a sane test, it passes against swrast.. Hmm on a second look inside mesa, it appears it never stores textures internally as BGRA, it always does a swizzle translate on the way in, so this test won't help me there, I'll have to think up something a bit more intricate to test this stuff. There's often texture swizzling involved in converting the user-provided image (GL_RGBA vs. GL_BGRA vs. GL_ABGR_EXT, etc) to the actual hardware texture format (MESA_FORMAT_RGBA, MESA_FORMAT_ARGB_REV, etc). BTW, people concerned with glTexImage() performance should do some experimentation with different source formats/types to find one that (hopefully) avoids swizzling and can just be memcpy'd. For swrast, Mesa prefers the MESA_FORMAT_RGBA format for slightly faster software rendering on some paths. If you want to force a different internal format for testing with swrast, just modify the _mesa_choose_tex_format() function in texformat.c. There's similar code for gallium in st_ChooseTextureFormat(). There's a glean test (packedPixels??) that exercises all the different glTexImage() format/type combinations if you're looking for something that will hit different texture formats. -Brian ___ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
Re: [Mesa-dev] EXT_tetxure_swizzle and BGRA textures : glean test enhancement
On Mon, 2010-05-03 at 10:29 -0700, José Fonseca wrote: On Mon, 2010-05-03 at 09:44 -0700, Brian Paul wrote: Jose Fonseca wrote: I read the extension and it is not crystal clear, but it seems to imply the swizzles are orthogonal to the format, and applied as the very last step before being used in a shader. That is, the semantics are the same of adding a swizzle instruction after a TEX opcode, regardless of the format. At least this is my interpretation of The values of the texture parameters TEXTURE_SWIZZLE_R_EXT, TEXTURE_SWIZZLE_G_EXT, TEXTURE_SWIZZLE_B_EXT, and TEXTURE_SWIZZLE_A_EXT, are applied after the swizzling described in Table 3.20 (p. 186). The swizzle parameter TEXTURE_SWIZZLE_R_EXT affects the first component of Cs as: Correct. BGRA extension does not specify additions to the 3.20 table though (it's against spec 1.1) so this is why the guess work. So my expectaction is that swizzling a BGRA with a .rgba swizzle will get bgra. Mmm, I don't think so. Regardless of the original user texture component ordering and regardless of the actually hardware texture format, when the shader calls texture2D(sampler, coord), for example, it _always_ returns a vector of (R, G, B, A) in that order. Similarly for ARB_vp/fp and fixed-function texture sampling. We'd have a miserable time writing shaders if we texture2D(sampler, coord) returned different component orderings depending on the actual texture format (which could vary from one system to another). Actually, this is what I meant, but I see now I explained miserably! (@_@) What I meant is that if the user specifies a BGRA texture with the _bytes_: X Y Z W and we specify the TEXTURE_SWIZZLEs as (R, G, B, A) then we'd obtain W Z W X. I must be getting dyslexic. Z Y X W should be the answer. in the shader (normalized by 1/255). What I mean is that the format swizzles have to be composed with the shader swizzles. An extenstion like GL_EXT_bgra is used to describe the incoming/user texture data to glTexImage2D, nothing about the internal/actual texture layout. Yes. Jose ___ 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
Re: [Mesa-dev] EXT_tetxure_swizzle and BGRA textures : glean test enhancement
On Sat, May 1, 2010 at 6:47 PM, Dave Airlie airl...@gmail.com wrote: In looking at adding EXT_texture_swizzle I'm a bit confused about what exactly should happen with BGRA textures, as on r300 we use the texture swizzling to do BGRA, so we would have some interaction at that point. To make sure we test for this I've made the following enhancments to the glean test (in piglit tree - but I'll resubmit against glean tree if correct). Can someone with a clue make sure this is a sane test, it passes against swrast.. Hmm on a second look inside mesa, it appears it never stores textures internally as BGRA, it always does a swizzle translate on the way in, so this test won't help me there, I'll have to think up something a bit more intricate to test this stuff. Dave. ___ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
Re: [Mesa-dev] EXT_tetxure_swizzle and BGRA textures : glean test enhancement
I read the extension and it is not crystal clear, but it seems to imply the swizzles are orthogonal to the format, and applied as the very last step before being used in a shader. That is, the semantics are the same of adding a swizzle instruction after a TEX opcode, regardless of the format. At least this is my interpretation of The values of the texture parameters TEXTURE_SWIZZLE_R_EXT, TEXTURE_SWIZZLE_G_EXT, TEXTURE_SWIZZLE_B_EXT, and TEXTURE_SWIZZLE_A_EXT, are applied after the swizzling described in Table 3.20 (p. 186). The swizzle parameter TEXTURE_SWIZZLE_R_EXT affects the first component of Cs as: BGRA extension does not specify additions to the 3.20 table though (it's against spec 1.1) so this is why the guess work. So my expectaction is that swizzling a BGRA with a .rgba swizzle will get bgra. It is also interesting the mention that the swizzle happens after texture compare mode. Jose From: mesa-dev-bounces+jfonseca=vmware@lists.freedesktop.org [mesa-dev-bounces+jfonseca=vmware@lists.freedesktop.org] On Behalf Of Dave Airlie [airl...@gmail.com] Sent: Sunday, May 02, 2010 10:01 To: mesa-dev@lists.freedesktop.org Subject: Re: [Mesa-dev] EXT_tetxure_swizzle and BGRA textures : glean test enhancement On Sat, May 1, 2010 at 6:47 PM, Dave Airlie airl...@gmail.com wrote: In looking at adding EXT_texture_swizzle I'm a bit confused about what exactly should happen with BGRA textures, as on r300 we use the texture swizzling to do BGRA, so we would have some interaction at that point. To make sure we test for this I've made the following enhancments to the glean test (in piglit tree - but I'll resubmit against glean tree if correct). Can someone with a clue make sure this is a sane test, it passes against swrast.. Hmm on a second look inside mesa, it appears it never stores textures internally as BGRA, it always does a swizzle translate on the way in, so this test won't help me there, I'll have to think up something a bit more intricate to test this stuff. Dave. ___ 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
