//=============================================================================
  // Water.h by Frank Luna (C) 2004 All Rights Reserved.
  //
  // Note: If you want large bodies of water, then you should break
  //       the water mesh into sub-grids like we did with the terrain
  //       so that you can frustum cull.
  //=============================================================================
  
  ifndef WATER_H
  define WATER_H
  
  include <d3dUtil.h>
  
  class Water
  {
  public:
          struct InitInfo
          {
                  DirLight dirLight;
                  Mtrl     mtrl;
                  int      vertRows;
                  int      vertCols;
                  float    dx;
                  float    dz;
                  std::string waveMapFilename0;
                  std::string waveMapFilename1;
                  D3DXVECTOR2 waveMapVelocity0;
                  D3DXVECTOR2 waveMapVelocity1;
                  float texScale;
                  D3DXMATRIX toWorld;
          };
  
  public:
          Water(InitInfo& initInfo);
  
          ~Water();
  
          DWORD getNumTriangles();
          DWORD getNumVertices();
  
          void onLostDevice();
          void onResetDevice();
  
          void update(float dt);
          void draw();
  
          void setEnvMap(IDirect3DCubeTexture9* envMap);
  
  private:
          void buildFX();
  
  private:
          ID3DXMesh* mMesh;
          ID3DXEffect* mFX;
  
          // The two normal maps to scroll.
          IDirect3DTexture9* mWaveMap0;
          IDirect3DTexture9* mWaveMap1;
  
          // Offset of normal maps for scrolling (vary as a function of time)
          D3DXVECTOR2 mWaveMapOffset0;
          D3DXVECTOR2 mWaveMapOffset1;
  
          InitInfo mInitInfo;
          float mWidth;
          float mDepth;
  
          D3DXHANDLE mhTech;
          D3DXHANDLE mhWVP;
          D3DXHANDLE mhWorld;
          D3DXHANDLE mhWorldInv;
          D3DXHANDLE mhLight;
          D3DXHANDLE mhMtrl;
          D3DXHANDLE mhEyePosW;
          D3DXHANDLE mhWaveMap0;
          D3DXHANDLE mhWaveMap1;
          D3DXHANDLE mhWaveMapOffset0;
          D3DXHANDLE mhWaveMapOffset1;
          D3DXHANDLE mhEnvMap;
  };
  
  endif // WATER_H