Rework environment map importance sampling to vulkan and hlsl #946
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| namespace workgroup | ||
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wrong namespace
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nbl::hlsl::concepts::accessors
| namespace workgroup | ||
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| namespace envmap |
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you're not in workgroup anything, also envmap should be image_importance_sampling
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actually nbl::hlsl::sampling and nbl/builtin/hlsl/sampling folder
| #define level NBL_CONCEPT_PARAM_T NBL_CONCEPT_PARAM_2 | ||
| #define offset NBL_CONCEPT_PARAM_T NBL_CONCEPT_PARAM_3 | ||
| NBL_CONCEPT_END( | ||
| ((NBL_CONCEPT_REQ_EXPR_RET_TYPE)((a.template get(uv,level,offset)) , ::nbl::hlsl::is_same_v, float32_t4>)) |
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this is the same as the MipmappedLoadableImage accessor
make the get return a float32_t instead of float32_t4 then a new concept is justified.
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| template <typename LuminanceAccessor, typename OutputAccessor NBL_FUNC_REQUIRES (envmap::LuminanceReadAccessor<LuminanceAccessor> && envmap::WarpmapWriteAccessor<OutputAccessor>) | ||
| // TODO(kevinyu): Should lumapMapSize and warpMapSize provided by Accessor? |
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not necessary, this is fine, make the const though
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Take the xi from the outside and never ask about the warpMapSize
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also no write accessor necessary
| const uint32_t threadID = uint32_t(SubgroupContiguousIndex()); | ||
| const uint32_t lastWarpMapPixel = warpMapSize - uint32_t2(1, 1); | ||
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| if (all(threadID < warpMapSize)) | ||
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| float32_t2 xi = float32_t2(threadID) / float32_t2(lastWarpMapPixel); |
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nope, threadID is 1D, AND its in 0,512
There's nothing "workgroup" about this.
Take the xi from the outside and never ask about the warpMapSize
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also when you move the code outside, leave comments about why the xi calculation is like that (corner sampled images)
| namespace envmap | ||
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| struct WarpmapGeneration |
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rename to Image , this could be used to importance sample without a warpmap given a xi like all the other sampling structs in nbl/builtin/hlsl/sampling
warpmap just caches the results in a LUT for a grid of xi inputs
| // TODO(kevinyu): Implement findMSB | ||
| const uint32_t2 mip2x1 = findMSB(lumaMapSize.x) - 1; |
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maybe ask for the uint32_t lumaMapWidthLog2 and bool aspectRatio2_1 instead of lumaMapSize
| // do one split in the X axis first cause penultimate full mip would have been 2x1 | ||
| p.x = impl::choseSecond(luminanceAccessor.get(uint32_t2(0, 0), mip2x1, uint32_t2(0, 0)), luminanceAccessor.get(uint32_t2(0, 0), mip2x1, uint32_t2(1, 0), xi.x) ? 1 : 0; |
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to support octahedral maps (which are 1:1 apsect raito) only do this split if (aspectRatio2_1), and initialize p.x to 0 at the time p.y gets initialized
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| const float32_t2 directionUV = (float32_t2(p.x, p.y) + xi) / float32_t2(lumaMapSize); |
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comments, comments, lets not let the discord discussions go to waste
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| const float32_t2 directionUV = (float32_t2(p.x, p.y) + xi) / float32_t2(lumaMapSize); | ||
| outputAccessor.set(threadID, directionUV); |
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don't use an output accessor here because we just want a sampling function, so just return directionUV
| const float32_t4 values = float32_t4( | ||
| luminanceAccessor.get(p, i, uint32_t2(0, 1)), | ||
| luminanceAccessor.get(p, i, uint32_t2(1, 1)), | ||
| luminanceAccessor.get(p, i, uint32_t2(1, 0)), | ||
| luminanceAccessor.get(p, i, uint32_t2(0, 0)) | ||
| ); |
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the get signature should be different, should be as if a textureGatherLod existed (which allows accessor to use textureGather + descriptor indexing for the mip-levels internally)
Description
Rework environment map importance sampling to vulkan and hlsl
Testing
Rework example 0 to use vulkan and hlsl
TODO list: