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#ifndef QSSG_RENDER_RENDER_IMAGE_TEXTURE_H
#define QSSG_RENDER_RENDER_IMAGE_TEXTURE_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 <QtQuick3DRender/private/qssgrenderbasetypes_p.h>
#include <QtQuick3DRender/private/qssgrenderbackend_p.h>

QT_BEGIN_NAMESPACE

class QSSGRenderContext;
class QSSGRenderTexture2D;

// a wrapper class for QSSGRenderTexture2D
// to use with compute shaders and load / store image shaders

class Q_QUICK3DRENDER_EXPORT QSSGRenderImage2D
{
    Q_DISABLE_COPY(QSSGRenderImage2D)
public:
    QAtomicInt ref;

private:
    QSSGRef<QSSGRenderContext> m_context; ///< pointer to context
    QSSGRef<QSSGRenderBackend> m_backend; ///< pointer to backend
    QSSGRef<QSSGRenderTexture2D> m_texture2D; ///< pointer to texture
    qint32 m_textureUnit; ///< texture unit this texture should use
    QSSGRenderImageAccessType m_accessType; ///< texture / image access type ( read, write, read_write )
    quint32 m_textureLevel; ///< texture level we use for this image

public:
    /**
     * @brief constructor
     *
     * @param[in] context		Pointer to context
     * @param[in] fnd			Pointer to foundation
     * @param[in] inTexture		Pointer to a QSSGRenderTexture2D object
     * @param[in] inAccess		Image access type ( read, write, read_write )
     *
     * @return No return.
     */
    QSSGRenderImage2D(const QSSGRef<QSSGRenderContext> &context,
                        const QSSGRef<QSSGRenderTexture2D> &inTexture,
                        QSSGRenderImageAccessType inAccess);

    ~QSSGRenderImage2D();

    /**
     * @brief	Set the access rights within the shader.
     *			Can be read, write or read_write.
     *
     * @param[in] inAccess		Image access type ( read, write, read_write )
     *
     * @return No return.
     */
    void setAccessType(QSSGRenderImageAccessType inAccess) { m_accessType = inAccess; }

    /**
     * @brief	Set the texture level we use for this image
     *
     * @param[in] inLevel		texture level ( must be in range of max levels )
     *
     * @return No return.
     */
    void setTextureLevel(qint32 inLevel);

    /**
     * @brief	Get texture unit used
     *
     *
     * @return texture unit bound to.
     */
    quint32 textureUnit() const { return m_textureUnit; }

    /**
     * @brief Bind a texture for shader access
     *
     * @param[in] unit		The binding point
     *
     * @return No return.
     */
    void bind(qint32 unit);

    /**
     * @brief get the backend object handle
     *		  here we return the handle from the wrapped texture
     *
     * @return the backend object handle.
     */
    QSSGRenderBackend::QSSGRenderBackendTextureObject handle();

};

QT_END_NAMESPACE

#endif
