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#ifndef QSHADERDESCRIPTION_H
#define QSHADERDESCRIPTION_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists for the convenience
// of a number of Qt sources files.  This header file may change from
// version to version without notice, or even be removed.
//
// We mean it.
//

#include <QtGui/qtguiglobal.h>
#include <QtCore/QString>
#include <QtCore/QVector>
#include <array>

QT_BEGIN_NAMESPACE

struct QShaderDescriptionPrivate;

class Q_GUI_EXPORT QShaderDescription
{
public:
    QShaderDescription();
    QShaderDescription(const QShaderDescription &other);
    QShaderDescription &operator=(const QShaderDescription &other);
    ~QShaderDescription();
    void detach();

    bool isValid() const;

    QByteArray toBinaryJson() const;
    QByteArray toJson() const;

    static QShaderDescription fromBinaryJson(const QByteArray &data);

    enum VariableType {
        Unknown = 0,

        // do not reorder
        Float,
        Vec2,
        Vec3,
        Vec4,
        Mat2,
        Mat2x3,
        Mat2x4,
        Mat3,
        Mat3x2,
        Mat3x4,
        Mat4,
        Mat4x2,
        Mat4x3,

        Int,
        Int2,
        Int3,
        Int4,

        Uint,
        Uint2,
        Uint3,
        Uint4,

        Bool,
        Bool2,
        Bool3,
        Bool4,

        Double,
        Double2,
        Double3,
        Double4,
        DMat2,
        DMat2x3,
        DMat2x4,
        DMat3,
        DMat3x2,
        DMat3x4,
        DMat4,
        DMat4x2,
        DMat4x3,

        Sampler1D,
        Sampler2D,
        Sampler2DMS,
        Sampler3D,
        SamplerCube,
        Sampler1DArray,
        Sampler2DArray,
        Sampler2DMSArray,
        Sampler3DArray,
        SamplerCubeArray,
        SamplerRect,
        SamplerBuffer,

        Image1D,
        Image2D,
        Image2DMS,
        Image3D,
        ImageCube,
        Image1DArray,
        Image2DArray,
        Image2DMSArray,
        Image3DArray,
        ImageCubeArray,
        ImageRect,
        ImageBuffer,

        Struct
    };

    enum ImageFormat {
        // must match SPIR-V's ImageFormat
        ImageFormatUnknown = 0,
        ImageFormatRgba32f = 1,
        ImageFormatRgba16f = 2,
        ImageFormatR32f = 3,
        ImageFormatRgba8 = 4,
        ImageFormatRgba8Snorm = 5,
        ImageFormatRg32f = 6,
        ImageFormatRg16f = 7,
        ImageFormatR11fG11fB10f = 8,
        ImageFormatR16f = 9,
        ImageFormatRgba16 = 10,
        ImageFormatRgb10A2 = 11,
        ImageFormatRg16 = 12,
        ImageFormatRg8 = 13,
        ImageFormatR16 = 14,
        ImageFormatR8 = 15,
        ImageFormatRgba16Snorm = 16,
        ImageFormatRg16Snorm = 17,
        ImageFormatRg8Snorm = 18,
        ImageFormatR16Snorm = 19,
        ImageFormatR8Snorm = 20,
        ImageFormatRgba32i = 21,
        ImageFormatRgba16i = 22,
        ImageFormatRgba8i = 23,
        ImageFormatR32i = 24,
        ImageFormatRg32i = 25,
        ImageFormatRg16i = 26,
        ImageFormatRg8i = 27,
        ImageFormatR16i = 28,
        ImageFormatR8i = 29,
        ImageFormatRgba32ui = 30,
        ImageFormatRgba16ui = 31,
        ImageFormatRgba8ui = 32,
        ImageFormatR32ui = 33,
        ImageFormatRgb10a2ui = 34,
        ImageFormatRg32ui = 35,
        ImageFormatRg16ui = 36,
        ImageFormatRg8ui = 37,
        ImageFormatR16ui = 38,
        ImageFormatR8ui = 39
    };

    enum ImageFlag {
        ReadOnlyImage = 1 << 0,
        WriteOnlyImage = 1 << 1
    };
    Q_DECLARE_FLAGS(ImageFlags, ImageFlag)

    // Optional data (like decorations) usually default to an otherwise invalid value (-1 or 0). This is intentional.

    struct InOutVariable {
        QString name;
        VariableType type = Unknown;
        int location = -1;
        int binding = -1;
        int descriptorSet = -1;
        ImageFormat imageFormat = ImageFormatUnknown;
        ImageFlags imageFlags;
    };

    struct BlockVariable {
        QString name;
        VariableType type = Unknown;
        int offset = 0;
        int size = 0;
        QVector<int> arrayDims;
        int arrayStride = 0;
        int matrixStride = 0;
        bool matrixIsRowMajor = false;
        QVector<BlockVariable> structMembers;
    };

    struct UniformBlock {
        QString blockName;
        QString structName; // instanceName
        int size = 0;
        int binding = -1;
        int descriptorSet = -1;
        QVector<BlockVariable> members;
    };

    struct PushConstantBlock {
        QString name;
        int size = 0;
        QVector<BlockVariable> members;
    };

    struct StorageBlock {
        QString blockName;
        QString instanceName;
        int knownSize = 0;
        int binding = -1;
        int descriptorSet = -1;
        QVector<BlockVariable> members;
    };

    QVector<InOutVariable> inputVariables() const;
    QVector<InOutVariable> outputVariables() const;
    QVector<UniformBlock> uniformBlocks() const;
    QVector<PushConstantBlock> pushConstantBlocks() const;
    QVector<StorageBlock> storageBlocks() const;
    QVector<InOutVariable> combinedImageSamplers() const;
    QVector<InOutVariable> storageImages() const;

    std::array<uint, 3> computeShaderLocalSize() const;

private:
    QShaderDescriptionPrivate *d;
    friend struct QShaderDescriptionPrivate;
#ifndef QT_NO_DEBUG_STREAM
    friend Q_GUI_EXPORT QDebug operator<<(QDebug, const QShaderDescription &);
#endif
};

Q_DECLARE_OPERATORS_FOR_FLAGS(QShaderDescription::ImageFlags)

#ifndef QT_NO_DEBUG_STREAM
Q_GUI_EXPORT QDebug operator<<(QDebug, const QShaderDescription &);
Q_GUI_EXPORT QDebug operator<<(QDebug, const QShaderDescription::InOutVariable &);
Q_GUI_EXPORT QDebug operator<<(QDebug, const QShaderDescription::BlockVariable &);
Q_GUI_EXPORT QDebug operator<<(QDebug, const QShaderDescription::UniformBlock &);
Q_GUI_EXPORT QDebug operator<<(QDebug, const QShaderDescription::PushConstantBlock &);
Q_GUI_EXPORT QDebug operator<<(QDebug, const QShaderDescription::StorageBlock &);
#endif

QT_END_NAMESPACE

#endif