src/dawn/common/ExternalTextureParams.h

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#ifndef SRC_DAWN_COMMON_EXTERNALTEXTUREPARAMS_H_
#define SRC_DAWN_COMMON_EXTERNALTEXTUREPARAMS_H_

#include <webgpu/webgpu_cpp.h>

#include <array>

namespace dawn {

// Color space parameters that can be passed to an ExternalTexture.
struct ExternalTextureColorSpaceParams {
    // Stored row-major to save uniform buffer space. (so one full row after another)
    // TODO(https://crbug.com/496604550): That's an implementation detail that should not be exposed
    // in the API, Dawn can transpose internally.
    std::array<float, 12> yuvToRgbConversionMatrix;
    std::array<float, 7> srcTransferFunction = {};
    std::array<float, 7> dstTransferFunction = {};  // Really the inverse transfer function.
    // Stored column major to match WGSL. (so one full column after another)
    std::array<float, 9> gamutConversionMatrix;
};

// Helper function to make parameters for an ExternalTextureDescriptor
wgpu::Status ComputeExternalTextureParams(const wgpu::ColorSpaceDawn& srcColorSpace,
                                          wgpu::PredefinedColorSpace dstColorSpace,
                                          ExternalTextureColorSpaceParams* out);

ExternalTextureColorSpaceParams GetNoopColorSpaceParams();

}  // namespace dawn

#endif  // SRC_DAWN_COMMON_EXTERNALTEXTUREPARAMS_H_