Method quantizeTexCoords

Source/Falcor/Scene/SceneBuilder.cpp:2591–2642

    }

    void SceneBuilder::quantizeTexCoords()
    {
        // Match texture coordinate quantization for textured emissives to format of PackedEmissiveTriangle.
        // This is to avoid mismatch when sampling and evaluating emissive triangles.
        // Note that non-emissive meshes are unmodified and use full precision texcoords.
        for (auto& mesh : mMeshes)
        {
            const auto& pMaterial = mSceneData.pMaterials->getMaterial(mesh.materialId)->toBasicMaterial();
            if (pMaterial && pMaterial->getEmissiveTexture() != nullptr)
            {
                // Quantize texture coordinates to fp16. Also track the bounds and max error.
                float2 minTexCrd = float2(std::numeric_limits<float>::infinity());
                float2 maxTexCrd = float2(-std::numeric_limits<float>::infinity());
                float2 maxError = float2(0);

                for (uint32_t i = 0; i < mesh.staticVertexCount; ++i)
                {
                    auto& v = mSceneData.meshStaticData[mesh.staticVertexOffset + i];
                    float2 texCrd = v.texCrd;
                    minTexCrd = min(minTexCrd, texCrd);
                    maxTexCrd = max(maxTexCrd, texCrd);
                    v.texCrd = f16tof32(f32tof16(texCrd));
                    maxError = max(maxError, abs(v.texCrd - texCrd));
                }

                // Issue warning if quantization errors are too large.
                float2 maxAbsCrd = max(abs(minTexCrd), abs(maxTexCrd));
                if (maxAbsCrd.x > HLF_MAX || maxAbsCrd.y > HLF_MAX)
                {
                    logWarning("Texture coordinates for emissive textured mesh '{}' are outside the representable range, expect rendering errors.", mesh.name);
                }
                else
                {
                    // Compute maximum quantization error in texels.
                    // The texcoords are used for all texture channels so taking the maximum dimensions.
                    uint2 maxTexDim = pMaterial->getMaxTextureDimensions();
                    maxError *= float2(maxTexDim);
                    float maxTexelError = std::max(maxError.x, maxError.y);

                    if (maxTexelError > kMaxTexelError)
                    {
                        logWarning(
                            "Texture coordinates for emissive textured mesh '{}' have a large quantization error of {} texels."
                            "The coordinate range is [{},{}] x [{},{}] for maximum texture dimensions ({},{}).",
                            mesh.name, maxTexelError,
                            minTexCrd.x, maxTexCrd.x, minTexCrd.y, maxTexCrd.y, maxTexDim.x, maxTexDim.y
                        );
                    }
                }
            }
        }
    }

    void SceneBuilder::removeDuplicateSDFGrids()
    {