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#ifndef QT3DRENDER_RENDER_RENDERSTATE_H
#define QT3DRENDER_RENDER_RENDERSTATE_H

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

#include <Qt3DRender/private/genericstate_p.h>
#include <QVector>

QT_BEGIN_NAMESPACE

namespace Qt3DRender {

class QRenderState;

namespace Render {

class GraphicsContext;
class RenderState;

class RenderStateSet
{
public:
    RenderStateSet();
    ~RenderStateSet();

    void addState(RenderState* ds);

    /**
     * @brief changeCost - metric of cost to change to this state-set from
     * a candidate previous state-set. This is used to find an optimal
     * ordering of state-sets when sending draw commands.
     * @param previousState
     * @return
     */
    int changeCost(RenderStateSet* previousState);

    void apply(GraphicsContext* gc);

    StateMaskSet stateMask() const;
    void merge(RenderStateSet *other);
    void resetMasked(StateMaskSet maskOfStatesToReset, GraphicsContext* gc);
private:
    /**
     * @brief contains - check if this set contains a matching piece of state
     * @param ds
     * @return
     */
    bool contains(RenderState* ds) const;

    QVector<RenderState*> m_states;

    StateMaskSet m_stateMask;

    RenderStateSet* m_cachedPrevious;
    QVector<RenderState*> m_cachedDeltaStates;
};

} // namespace Render
} // namespace Qt3DRender

QT_END_NAMESPACE

#endif // QT3DRENDER_RENDER_RENDERSTATE_H