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/*  Visualization Library                                                             */
/*  http://visualizationlibrary.org                                                   */
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#ifndef LODEvaluator_INCLUDE_ONCE
#define LODEvaluator_INCLUDE_ONCE

#include <vlCore/Object.hpp>

namespace vl
{
  class Actor;
  class Camera;

  //------------------------------------------------------------------------------
  /**
   * Abstract class to compute the appropriate LOD of an Actor or Effect
   *
   * \sa
   * - DistanceLODEvaluator
   * - PixelLODEvaluator
  */
  class VLGRAPHICS_EXPORT LODEvaluator: public Object
  {
    VL_INSTRUMENT_ABSTRACT_CLASS(vl::LODEvaluator, Object)

  public:
    LODEvaluator()
    {
      VL_DEBUG_SET_OBJECT_NAME()
    }
    virtual int evaluate(Actor* actor, Camera* camera) = 0;
  };
  //------------------------------------------------------------------------------
}

#endif