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#ifndef QSSG_RENDER_QUERY_BASE_H
#define QSSG_RENDER_QUERY_BASE_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

// forward declaration
class QSSGRenderContext;
class QSSGRenderBackend;

///< Base class
class QSSGRenderQueryBase
{
    Q_DISABLE_COPY(QSSGRenderQueryBase)
public:
    QAtomicInt ref;

protected:
    QSSGRef<QSSGRenderContext> m_context; ///< pointer to context
    QSSGRef<QSSGRenderBackend> m_backend; ///< pointer to backend
    QSSGRenderBackend::QSSGRenderBackendQueryObject m_handle; ///< opaque backend handle

    /**
     * @brief constructor
     *
     * @param[in] context		Pointer to context
     * @param[in] fnd			Pointer to foundation
     *
     * @return No return.
     */
    QSSGRenderQueryBase(const QSSGRef<QSSGRenderContext> &context);

public:
    virtual ~QSSGRenderQueryBase();

    /**
     * @brief Get query type
     *
     * @return Return query type
     */
    virtual QSSGRenderQueryType queryType() const = 0;

    /**
     * @brief begin a query
     *
     * @return no return.
     */
    virtual void begin() = 0;

    /**
     * @brief end a query
     *
     * @return no return.
     */
    virtual void end() = 0;

    /**
     * @brief Get the result of a query
     *
     * @param[out] params	Contains result of query regarding query type
     *
     * @return no return.
     */
    virtual void result(quint32 *params) = 0;

    /**
     * @brief get the backend object handle
     *
     * @return the backend object handle.
     */
    virtual QSSGRenderBackend::QSSGRenderBackendQueryObject handle() const { return m_handle; }
};

QT_END_NAMESPACE

#endif