blur_mask_material.h

#pragma once
 
#include <array>
#include <QSGMaterial>
#include <QVector2D>
#include <QVector4D>
#include "qml_material/scenegraph/texture_cache.h"
 
namespace qml_material::sg
{
 
enum class BlurStyle : int
{
    Normal = 0,
    Solid  = 1,
    Outer  = 2,
    Inner  = 3,
};
 
class BlurMaskMaterial : public QSGMaterial {
public:
    BlurMaskMaterial();
    ~BlurMaskMaterial() = default;
 
    QSGMaterialShader* createShader(QSGRendererInterface::RenderMode) const override;
    QSGMaterialType*   type() const override;
    int                compare(const QSGMaterial* other) const override;
 
    void init_profile_texture(QQuickWindow* win);
    auto profile_texture() -> QSGTexture*;
 
    void                       init_corner_textures(QQuickWindow* win);
    const CornerCutoutTexture& corner_texture(int index) const;
 
    // Uniform state (populated by the owning node each frame).
    float     sigma { 0.0f };
    QVector2D rect_size { 0.0f, 0.0f };
    QVector4D radius { 0.0f, 0.0f, 0.0f, 0.0f }; // TL, TR, BL, BR
    BlurStyle style { BlurStyle::Normal };
 
    [[nodiscard]] float effective_radius() const;
 
private:
    // Not owned; textures come from the per-window cache.
    QSGTexture*                        m_profile_texture { nullptr };
    std::array<CornerCutoutTexture, 4> m_corner_textures {};
};
 
class BlurMaskShader : public QSGMaterialShader {
public:
    BlurMaskShader();
 
    bool updateUniformData(QSGMaterialShader::RenderState& state, QSGMaterial* newMaterial,
                           QSGMaterial* oldMaterial) override;
 
    void updateSampledImage(RenderState&, int binding, QSGTexture** texture,
                            QSGMaterial* newMaterial, QSGMaterial*) override;
};
 
} // namespace qml_material::sg