qsgflatcolormaterial.cpp

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qsgflatcolormaterial.h"
#include <private/qsgmaterialshader_p.h>
 
QT_BEGIN_NAMESPACE
 
class FlatColorMaterialRhiShader : public QSGMaterialShader
{
public:
    FlatColorMaterialRhiShader(int viewCount);
 
    bool updateUniformData(RenderState &state, QSGMaterial *newMaterial, QSGMaterial *oldMaterial) override;
 
    static QSGMaterialType type;
};
 
QSGMaterialType FlatColorMaterialRhiShader::type;
 
FlatColorMaterialRhiShader::FlatColorMaterialRhiShader(int viewCount)
{
    setShaderFileName(VertexStage, QStringLiteral(":/qt-project.org/scenegraph/shaders_ng/flatcolor.vert.qsb"), viewCount);
    setShaderFileName(FragmentStage, QStringLiteral(":/qt-project.org/scenegraph/shaders_ng/flatcolor.frag.qsb"), viewCount);
}
 
bool FlatColorMaterialRhiShader::updateUniformData(RenderState &state,
                                                   QSGMaterial *newMaterial,
                                                   QSGMaterial *oldMaterial)
{
    Q_ASSERT(!oldMaterial || newMaterial->type() == oldMaterial->type());
    QSGFlatColorMaterial *oldMat = static_cast<QSGFlatColorMaterial *>(oldMaterial);
    QSGFlatColorMaterial *mat = static_cast<QSGFlatColorMaterial *>(newMaterial);
    bool changed = false;
    QByteArray *buf = state.uniformData();
    const int shaderMatrixCount = newMaterial->viewCount();
    const int matrixCount = qMin(state.projectionMatrixCount(), shaderMatrixCount);
 
    for (int viewIndex = 0; viewIndex < matrixCount; ++viewIndex) {
        if (state.isMatrixDirty()) {
            const QMatrix4x4 m = state.combinedMatrix(viewIndex);
            memcpy(buf->data() + 64 * viewIndex, m.constData(), 64);
            changed = true;
        }
    }
 
    const QColor &c = mat->color();
    if (!oldMat || c != oldMat->color() || state.isOpacityDirty()) {
        float r, g, b, a;
        c.getRgbF(&r, &g, &b, &a);
        const float opacity = state.opacity() * a;
        QVector4D v(r * opacity, g * opacity, b * opacity, opacity);
        Q_ASSERT(sizeof(v) == 16);
        memcpy(buf->data() + 64 * shaderMatrixCount, &v, 16);
        changed = true;
    }
 
    return changed;
}
 
 
/*!
    \class QSGFlatColorMaterial
 
    \brief The QSGFlatColorMaterial class provides a convenient way of rendering
    solid colored geometry in the scene graph.
 
    \inmodule QtQuick
    \ingroup qtquick-scenegraph-materials
 
    \warning This utility class is only functional when running with the default
    backend of the Qt Quick scenegraph.
 
    The flat color material will fill every pixel in a geometry using
    a solid color. The color can contain transparency.
 
    The geometry to be rendered with a flat color material requires
    vertices in attribute location 0 in the QSGGeometry object to render
    correctly. The QSGGeometry::defaultAttributes_Point2D() returns an attribute
    set compatible with this material.
 
    The flat color material respects both current opacity and current matrix
    when updating its rendering state.
 */
 
 
/*!
    Constructs a new flat color material.
 
    The default color is white.
 */
 
QSGFlatColorMaterial::QSGFlatColorMaterial() : m_color(QColor(255, 255, 255))
{
}
 
/*!
    \fn const QColor &QSGFlatColorMaterial::color() const
 
    Returns this flat color material's color.
 
    The default color is white.
 */
 
 
 
/*!
    Sets this flat color material's color to \a color.
 */
 
void QSGFlatColorMaterial::setColor(const QColor &color)
{
    m_color = color;
    setFlag(Blending, m_color.alpha() != 0xff);
}
 
 
 
/*!
    \internal
 */
 
QSGMaterialType *QSGFlatColorMaterial::type() const
{
    return &FlatColorMaterialRhiShader::type;
}
 
 
 
/*!
    \internal
 */
 
QSGMaterialShader *QSGFlatColorMaterial::createShader(QSGRendererInterface::RenderMode renderMode) const
{
    Q_UNUSED(renderMode);
    return new FlatColorMaterialRhiShader(viewCount());
}
 
 
/*!
    \internal
 */
 
int QSGFlatColorMaterial::compare(const QSGMaterial *other) const
{
    const QSGFlatColorMaterial *flat = static_cast<const QSGFlatColorMaterial *>(other);
    return m_color.rgba() - flat->color().rgba();
 
}
 
QT_END_NAMESPACE