text: /**************************************************************************************/
  /*                                                                                    */
  /*  Visualization Library                                                             */
  /*  http://visualizationlibrary.org                                                   */
  /*                                                                                    */
  /*  Copyright (c) 2005-2020, Michele Bosi                                             */
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  /*                                                                                    */
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  /*  list of conditions and the following disclaimer.                                  */
  /*                                                                                    */
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  /*  list of conditions and the following disclaimer in the documentation and/or       */
  /*  other materials provided with the distribution.                                   */
  /*                                                                                    */
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  /**************************************************************************************/
  
  #ifndef EnableSet_INCLUDE_ONCE
  #define EnableSet_INCLUDE_ONCE
  
  #include <vlCore/Object.hpp>
  #include <vlCore/vlnamespace.hpp>
  #include <vector>
  
  namespace vl
  {
    /**
     * A set of enables managed by Shader.
     * This class substitutes for the most part the OpenGL functions glEnable() and glDisable().
     *
     * \sa Shader, Effect, Actor
    */
    class EnableSet: public Object
    {
      VL_INSTRUMENT_CLASS(vl::EnableSet, Object)
  
    public:
      EnableSet(): mBlendingEnabled(false)
      {
        VL_DEBUG_SET_OBJECT_NAME()
        // these two are enabled by default
        mEnables.push_back(EN_DITHER);
        // only OpenGL ES 2 does not support GL_MULTISAMPLE
  #if !defined(VL_OPENGL_ES2)
        mEnables.push_back(EN_MULTISAMPLE);
  #endif
      }
  
      // enable getter and setters
  
      void enable(EEnable capability)
      {
        if (capability == EN_BLEND)
          mBlendingEnabled = true;
        for(unsigned i=0; i<mEnables.size(); ++i)
          if (mEnables[i] == capability)
            return;
        mEnables.push_back( capability );
      }
  
      void disable(EEnable capability)
      {
        if (capability == EN_BLEND)
          mBlendingEnabled = false;
        for(unsigned i=0; i<mEnables.size(); ++i)
        {
          if (mEnables[i] == capability)
          {
            mEnables.erase( mEnables.begin() + i );
            return;
          }
        }
      }
  
      const std::vector<EEnable>& enables() const { return mEnables; }
  
      int isEnabled(EEnable capability) const
      {
        for(unsigned i=0; i<mEnables.size(); ++i)
          if (mEnables[i] == capability)
            return true;
        return false;
      }
  
      void disableAll() { mEnables.clear(); mBlendingEnabled=false; }
  
      bool isBlendingEnabled() const { return mBlendingEnabled; }
  
    protected:
      std::vector<EEnable> mEnables;
      bool mBlendingEnabled;
    };
  }
  
  #endif
  