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#ifndef QOPENGLTEXTUREBLITTER_P_H
#define QOPENGLTEXTUREBLITTER_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include <QtGui/qopengl.h>
#include <QtGui/QMatrix3x3>

QT_BEGIN_NAMESPACE

class QOpenGLTextureBlitterPrivate;


class Q_GUI_EXPORT QOpenGLTextureBlitter
{
public:
    QOpenGLTextureBlitter();
    ~QOpenGLTextureBlitter();

    enum Origin {
        OriginBottomLeft,
        OriginTopLeft
    };

    bool create();
    bool isCreated() const;
    void destroy();

    bool supportsExternalOESTarget() const;

    void bind(GLenum target = GL_TEXTURE_2D);
    void release();

    void setSwizzleRB(bool swizzle);
    void setOpacity(float opacity);

    void blit(GLuint texture, const QMatrix4x4 &targetTransform, Origin sourceOrigin);
    void blit(GLuint texture, const QMatrix4x4 &targetTransform, const QMatrix3x3 &sourceTransform);

    static QMatrix4x4 targetTransform(const QRectF &target, const QRect &viewport);
    static QMatrix3x3 sourceTransform(const QRectF &subTexture, const QSize &textureSize, Origin origin);

private:
    Q_DISABLE_COPY(QOpenGLTextureBlitter);
    Q_DECLARE_PRIVATE(QOpenGLTextureBlitter);
    QScopedPointer<QOpenGLTextureBlitterPrivate> d_ptr;
};

QT_END_NAMESPACE

#endif //QOPENGLTEXTUREBLITTER_P_H