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#include "qsgvideonode_rgb_p.h"
#include <QtQuick/qsgtexturematerial.h>
#include <QtQuick/qsgmaterial.h>
#include <QtCore/qmutex.h>
#include <QtGui/QOpenGLContext>
#include <QtGui/QOpenGLFunctions>
#include <QtGui/QOpenGLShaderProgram>

QT_BEGIN_NAMESPACE

QList<QVideoFrame::PixelFormat> QSGVideoNodeFactory_RGB::supportedPixelFormats(
                                        QAbstractVideoBuffer::HandleType handleType) const
{
    QList<QVideoFrame::PixelFormat> pixelFormats;

    if (handleType == QAbstractVideoBuffer::NoHandle) {
        pixelFormats.append(QVideoFrame::Format_RGB32);
        pixelFormats.append(QVideoFrame::Format_ARGB32);
        pixelFormats.append(QVideoFrame::Format_BGR32);
        pixelFormats.append(QVideoFrame::Format_BGRA32);
        pixelFormats.append(QVideoFrame::Format_RGB565);
    }

    return pixelFormats;
}

QSGVideoNode *QSGVideoNodeFactory_RGB::createNode(const QVideoSurfaceFormat &format)
{
    if (supportedPixelFormats(format.handleType()).contains(format.pixelFormat()))
        return new QSGVideoNode_RGB(format);

    return 0;
}


class QSGVideoMaterialShader_RGB : public QSGMaterialShader
{
public:
    QSGVideoMaterialShader_RGB()
        : QSGMaterialShader(),
          m_id_matrix(-1),
          m_id_width(-1),
          m_id_rgbTexture(-1),
          m_id_opacity(-1)
    {
        setShaderSourceFile(QOpenGLShader::Vertex, QStringLiteral(":/qtmultimediaquicktools/shaders/rgbvideo_padded.vert"));
        setShaderSourceFile(QOpenGLShader::Fragment, QStringLiteral(":/qtmultimediaquicktools/shaders/rgbvideo.frag"));
    }

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

    char const *const *attributeNames() const override {
        static const char *names[] = {
            "qt_VertexPosition",
            "qt_VertexTexCoord",
            0
        };
        return names;
    }

protected:
    void initialize() override {
        m_id_matrix = program()->uniformLocation("qt_Matrix");
        m_id_width = program()->uniformLocation("width");
        m_id_rgbTexture = program()->uniformLocation("rgbTexture");
        m_id_opacity = program()->uniformLocation("opacity");
    }

    int m_id_matrix;
    int m_id_width;
    int m_id_rgbTexture;
    int m_id_opacity;
};

class QSGVideoMaterialShader_RGB_swizzle : public QSGVideoMaterialShader_RGB
{
public:
    QSGVideoMaterialShader_RGB_swizzle(bool hasAlpha)
        : m_hasAlpha(hasAlpha)
    {
        setShaderSourceFile(QOpenGLShader::Fragment, QStringLiteral(":/qtmultimediaquicktools/shaders/rgbvideo_swizzle.frag"));
    }

protected:
    void initialize() override {
        QSGVideoMaterialShader_RGB::initialize();
        program()->setUniformValue(program()->uniformLocation("hasAlpha"), GLboolean(m_hasAlpha));
    }

    bool m_hasAlpha;
};


class QSGVideoMaterial_RGB : public QSGMaterial
{
public:
    QSGVideoMaterial_RGB(const QVideoSurfaceFormat &format) :
        m_format(format),
        m_textureId(0),
        m_opacity(1.0),
        m_width(1.0)
    {
        setFlag(Blending, false);
    }

    ~QSGVideoMaterial_RGB()
    {
        if (m_textureId)
            QOpenGLContext::currentContext()->functions()->glDeleteTextures(1, &m_textureId);
    }

    QSGMaterialType *type() const override {
        static QSGMaterialType normalType, swizzleType;
        return needsSwizzling() ? &swizzleType : &normalType;
    }

    QSGMaterialShader *createShader() const override {
        const bool hasAlpha = m_format.pixelFormat() == QVideoFrame::Format_ARGB32;
        return needsSwizzling() ? new QSGVideoMaterialShader_RGB_swizzle(hasAlpha)
                                : new QSGVideoMaterialShader_RGB;
    }

    int compare(const QSGMaterial *other) const override {
        const QSGVideoMaterial_RGB *m = static_cast<const QSGVideoMaterial_RGB *>(other);

        if (!m_textureId)
            return 1;

        return m_textureId - m->m_textureId;
    }

    void updateBlending() {
        setFlag(Blending, qFuzzyCompare(m_opacity, qreal(1.0)) ? false : true);
    }

    void setVideoFrame(const QVideoFrame &frame) {
        QMutexLocker lock(&m_frameMutex);
        m_frame = frame;
    }

    void bind()
    {
        QOpenGLFunctions *functions = QOpenGLContext::currentContext()->functions();

        QMutexLocker lock(&m_frameMutex);
        if (m_frame.isValid()) {
            if (m_frame.map(QAbstractVideoBuffer::ReadOnly)) {
                QSize textureSize = m_frame.size();

                int stride = m_frame.bytesPerLine();
                switch (m_frame.pixelFormat()) {
                case QVideoFrame::Format_RGB565:
                    stride /= 2;
                    break;
                default:
                    stride /= 4;
                }

                m_width = qreal(m_frame.width()) / stride;
                textureSize.setWidth(stride);

                if (m_textureSize != textureSize) {
                    if (!m_textureSize.isEmpty())
                        functions->glDeleteTextures(1, &m_textureId);
                    functions->glGenTextures(1, &m_textureId);
                    m_textureSize = textureSize;
                }

                GLint dataType = GL_UNSIGNED_BYTE;
                GLint dataFormat = GL_RGBA;

                if (m_frame.pixelFormat() == QVideoFrame::Format_RGB565) {
                    dataType = GL_UNSIGNED_SHORT_5_6_5;
                    dataFormat = GL_RGB;
                }

                GLint previousAlignment;
                functions->glGetIntegerv(GL_UNPACK_ALIGNMENT, &previousAlignment);
                functions->glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

                functions->glActiveTexture(GL_TEXTURE0);
                functions->glBindTexture(GL_TEXTURE_2D, m_textureId);
                functions->glTexImage2D(GL_TEXTURE_2D, 0, dataFormat,
                                        m_textureSize.width(), m_textureSize.height(),
                                        0, dataFormat, dataType, m_frame.bits());

                functions->glPixelStorei(GL_UNPACK_ALIGNMENT, previousAlignment);

                functions->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
                functions->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
                functions->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
                functions->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

                m_frame.unmap();
            }
            m_frame = QVideoFrame();
        } else {
            functions->glActiveTexture(GL_TEXTURE0);
            functions->glBindTexture(GL_TEXTURE_2D, m_textureId);
        }
    }

    QVideoFrame m_frame;
    QMutex m_frameMutex;
    QSize m_textureSize;
    QVideoSurfaceFormat m_format;
    GLuint m_textureId;
    qreal m_opacity;
    GLfloat m_width;

private:
    bool needsSwizzling() const {
        return m_format.pixelFormat() == QVideoFrame::Format_RGB32
                || m_format.pixelFormat() == QVideoFrame::Format_ARGB32;
    }
};


QSGVideoNode_RGB::QSGVideoNode_RGB(const QVideoSurfaceFormat &format) :
    m_format(format)
{
    setFlag(QSGNode::OwnsMaterial);
    m_material = new QSGVideoMaterial_RGB(format);
    setMaterial(m_material);
}

QSGVideoNode_RGB::~QSGVideoNode_RGB()
{
}

void QSGVideoNode_RGB::setCurrentFrame(const QVideoFrame &frame, FrameFlags)
{
    m_material->setVideoFrame(frame);
    markDirty(DirtyMaterial);
}

void QSGVideoMaterialShader_RGB::updateState(const RenderState &state,
                                                QSGMaterial *newMaterial,
                                                QSGMaterial *oldMaterial)
{
    Q_UNUSED(oldMaterial);
    QSGVideoMaterial_RGB *mat = static_cast<QSGVideoMaterial_RGB *>(newMaterial);
    program()->setUniformValue(m_id_rgbTexture, 0);

    mat->bind();

    program()->setUniformValue(m_id_width, mat->m_width);
    if (state.isOpacityDirty()) {
        mat->m_opacity = state.opacity();
        mat->updateBlending();
        program()->setUniformValue(m_id_opacity, GLfloat(mat->m_opacity));
    }

    if (state.isMatrixDirty())
        program()->setUniformValue(m_id_matrix, state.combinedMatrix());
}

QT_END_NAMESPACE