src/tint/api/common/bindings.h

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#ifndef SRC_TINT_API_COMMON_BINDINGS_H_
#define SRC_TINT_API_COMMON_BINDINGS_H_

#include <unordered_map>

#include "src/tint/api/common/binding_point.h"
#include "src/tint/utils/reflection/reflection.h"

namespace tint {

/// A multiplanar external texture
struct ExternalMultiplanarTexture {
    /// Metadata
    BindingPoint metadata{};
    /// Plane0 binding data
    BindingPoint plane0{};
    /// Plane1 binding data
    BindingPoint plane1{};

    /// Reflect the fields of this class so that it can be used by tint::ForeachField()
    TINT_REFLECT(ExternalMultiplanarTexture, metadata, plane0, plane1);
    TINT_REFLECT_HASH_CODE(ExternalMultiplanarTexture);
    bool operator==(const ExternalMultiplanarTexture&) const = default;
};

/// A YCBcr external texture
struct ExternalYCBCRTexture {
    /// Metadata
    BindingPoint metadata{};
    /// texture binding data
    BindingPoint texture{};
    /// sampler binding data
    BindingPoint sampler{};

    /// Reflect the fields of this class so that it can be used by tint::ForeachField()
    TINT_REFLECT(ExternalYCBCRTexture, metadata, texture, sampler);
    TINT_REFLECT_HASH_CODE(ExternalYCBCRTexture);
    bool operator==(const ExternalYCBCRTexture&) const = default;
};

using BindingMap = std::unordered_map<BindingPoint, BindingPoint>;
using ExternalTextureBindings =
    std::unordered_map<BindingPoint,
                       std::variant<ExternalMultiplanarTexture, ExternalYCBCRTexture>>;

/// Binding information
struct Bindings {
    /// Uniform bindings
    BindingMap uniform{};
    /// Storage bindings
    BindingMap storage{};
    /// Texture bindings
    BindingMap texture{};
    /// Storage texture bindings
    BindingMap storage_texture{};
    /// Texel buffer bindings
    BindingMap texel_buffer{};
    /// Sampler bindings
    BindingMap sampler{};
    /// External bindings
    ExternalTextureBindings external_texture{};
    /// Input attachment bindings
    BindingMap input_attachment{};

    /// Reflect the fields of this class so that it can be used by tint::ForeachField()
    TINT_REFLECT(Bindings,
                 uniform,
                 storage,
                 texture,
                 storage_texture,
                 texel_buffer,
                 sampler,
                 external_texture,
                 input_attachment);

    TINT_REFLECT_HASH_CODE(Bindings);

    bool operator==(const Bindings&) const = default;
};

}  // namespace tint

#endif  // SRC_TINT_API_COMMON_BINDINGS_H_