qskinny/examples/iot-dashboard/kirigami/scenegraph/shadowedrectanglematerial.h

/*
 *  SPDX-FileCopyrightText: 2020 Arjen Hiemstra <ahiemstra@heimr.nl>
 *
 *  SPDX-License-Identifier: LGPL-2.0-or-later
 */

#pragma once

#include <QSGMaterial>
#include <QSGMaterialShader>
#include <QColor>

/**
 * A material rendering a rectangle with a shadow.
 *
 * This material uses a distance field shader to render a rectangle with a
 * shadow below it, optionally with rounded corners.
 */
class ShadowedRectangleMaterial : public QSGMaterial
{
    public:
        enum class ShaderType
        {
            Standard,
            LowPower
        };

        ShadowedRectangleMaterial();

        QSGMaterialShader* createShader() const override;
        QSGMaterialType* type() const override;
        int compare( const QSGMaterial* other ) const override;

        QVector2D aspect = QVector2D{1.0, 1.0};
        float size = 0.0;
        QVector4D radius = QVector4D{0.0, 0.0, 0.0, 0.0};
        QColor color = Qt::white;
        QColor shadowColor = Qt::black;
        QVector2D offset;
        ShaderType shaderType = ShaderType::Standard;

        static QSGMaterialType staticType;
};

class ShadowedRectangleShader : public QSGMaterialShader
{
    public:
        ShadowedRectangleShader( ShadowedRectangleMaterial::ShaderType shaderType );

        char const* const* attributeNames() const override;

        void initialize() override;
        void updateState( const QSGMaterialShader::RenderState& state, QSGMaterial* newMaterial, QSGMaterial* oldMaterial ) override;

    protected:
        void setShader( ShadowedRectangleMaterial::ShaderType shaderType, const QString& shader );

    private:
        int m_matrixLocation = -1;
        int m_opacityLocation = -1;
        int m_aspectLocation = -1;
        int m_sizeLocation = -1;
        int m_radiusLocation = -1;
        int m_colorLocation = -1;
        int m_shadowColorLocation = -1;
        int m_offsetLocation = -1;
};