//=============================================================================
  // DisplacementMapDemo.cpp by Frank Luna (C) 2005 All Rights Reserved.
  //
  // Demonstrates displacement mapping.
  //
  // Controls: Use mouse to look and 'W', 'S', 'A', and 'D' keys to move.
  //=============================================================================
  
  include <d3dApp.h>
  include <DirectInput.h>
  include <crtdbg.h>
  include <GfxStats.h>
  include <list>
  include <Camera.h>
  include <Sky.h>
  include <WaterDmap.h>
  include <Vertex.h>
  
  class DisplacementMapDemo : public D3DApp
  {
  public:
          DisplacementMapDemo(HINSTANCE hInstance, std::string winCaption, D3DDEVTYPE devType, DWORD requestedVP);
          ~DisplacementMapDemo();
  
          bool checkDeviceCaps();
          void onLostDevice();
          void onResetDevice();
          void updateScene(float dt);
          void drawScene();
  
  private:
          GfxStats* mGfxStats;
          Sky* mSky;
          WaterDMap* mWater;
          DirLight mLight;
  };
  
  int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE prevInstance,
                                     PSTR cmdLine, int showCmd)
  {
          // Enable run-time memory check for debug builds.
          #if defined(DEBUG) | defined(_DEBUG)
                  _CrtSetDbgFlag( _CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF );
          #endif
  
          // Construct camera before application, since the application uses the camera.
          Camera camera;
          gCamera = &camera;
  
          DisplacementMapDemo app(hInstance, "Displacement Map Demo", D3DDEVTYPE_HAL, D3DCREATE_HARDWARE_VERTEXPROCESSING);
          gd3dApp = &app;
  
          DirectInput di(DISCL_NONEXCLUSIVE|DISCL_FOREGROUND, DISCL_NONEXCLUSIVE|DISCL_FOREGROUND);
          gDInput = &di;
  
      return gd3dApp->run();
  }
  
  DisplacementMapDemo::DisplacementMapDemo(HINSTANCE hInstance, std::string winCaption, D3DDEVTYPE devType, DWORD requestedVP)
  : D3DApp(hInstance, winCaption, devType, requestedVP)
  {
          if(!checkDeviceCaps())
          {
                  MessageBox(0, "checkDeviceCaps() Failed", 0, 0);
                  PostQuitMessage(0);
          }
  
          InitAllVertexDeclarations();
  
          mLight.dirW = D3DXVECTOR3(0.0f, -1.0f, -3.0f);
          D3DXVec3Normalize(&mLight.dirW, &mLight.dirW);
          mLight.ambient = D3DXCOLOR(0.3f, 0.3f, 0.3f, 1.0f);
          mLight.diffuse = D3DXCOLOR(1.0f, 1.0f, 1.0f, 1.0f);
          mLight.spec    = D3DXCOLOR(0.7f, 0.7f, 0.7f, 1.0f);
  
          mGfxStats = new GfxStats();
          mSky = new Sky("grassenvmap1024.dds", 10000.0f);
  
          D3DXMATRIX waterWorld;
          D3DXMatrixIdentity(&waterWorld);
          
          Mtrl waterMtrl;
          waterMtrl.ambient   = D3DXCOLOR(0.4f, 0.4f, 0.7f, 0.0f);
          waterMtrl.diffuse   = D3DXCOLOR(0.4f, 0.4f, 0.7f, 1.0f);
          waterMtrl.spec      = 0.8f*WHITE;
          waterMtrl.specPower = 128.0f;
  
          WaterDMap::InitInfo waterInitInfo;
          waterInitInfo.dirLight = mLight;
          waterInitInfo.mtrl     = waterMtrl;
          waterInitInfo.fxFilename = "waterdmap.fx";
          waterInitInfo.vertRows         = 128;
          waterInitInfo.vertCols         = 128;
          waterInitInfo.dx               = 0.25f;
          waterInitInfo.dz               = 0.25f;
          waterInitInfo.waveMapFilename0 = "wave0.dds";
          waterInitInfo.waveMapFilename1 = "wave1.dds";
          waterInitInfo.dmapFilename0    = "waterdmap0.dds";
          waterInitInfo.dmapFilename1    = "waterdmap1.dds";
          waterInitInfo.waveNMapVelocity0 = D3DXVECTOR2(0.05f, 0.07f);
          waterInitInfo.waveNMapVelocity1 = D3DXVECTOR2(-0.01f, 0.13f);
          waterInitInfo.waveDMapVelocity0 = D3DXVECTOR2(0.012f, 0.015f);
          waterInitInfo.waveDMapVelocity1 = D3DXVECTOR2(0.014f, 0.05f);
          waterInitInfo.scaleHeights      = D3DXVECTOR2(0.7f, 1.1f);
          waterInitInfo.texScale = 8.0f;
          waterInitInfo.toWorld = waterWorld;
   
          mWater = new WaterDMap(waterInitInfo);
          
          // Initialize camera.
          gCamera->pos().y = 1.0f;
          gCamera->pos().z = -15.0f;
          gCamera->setSpeed(5.0f);
  
          mGfxStats->addVertices(mWater->getNumVertices());
          mGfxStats->addTriangles(mWater->getNumTriangles());
  
          mGfxStats->addVertices(mSky->getNumVertices());
          mGfxStats->addTriangles(mSky->getNumTriangles());
  
          onResetDevice();
  }
  
  DisplacementMapDemo::~DisplacementMapDemo()
  {
          delete mGfxStats;
          delete mSky;
          delete mWater;
  
          DestroyAllVertexDeclarations();
  }
  
  bool DisplacementMapDemo::checkDeviceCaps()
  {
          D3DCAPS9 caps;
          HR(gd3dDevice->GetDeviceCaps(&caps));
  
          // Check for vertex shader version 3.0 support.
          if( caps.VertexShaderVersion < D3DVS_VERSION(3, 0) )
                  return false;
  
          // Check for pixel shader version 3.0 support.
          if( caps.PixelShaderVersion < D3DPS_VERSION(3, 0) )
                  return false;
  
          return true;
  }
  
  void DisplacementMapDemo::onLostDevice()
  {
          mGfxStats->onLostDevice();
          mSky->onLostDevice();
          mWater->onLostDevice();
  }
  
  void DisplacementMapDemo::onResetDevice()
  {
          mGfxStats->onResetDevice();
          mSky->onResetDevice();
          mWater->onResetDevice();
  
          // The aspect ratio depends on the backbuffer dimensions, which can 
          // possibly change after a reset.  So rebuild the projection matrix.
          float w = (float)md3dPP.BackBufferWidth;
          float h = (float)md3dPP.BackBufferHeight;
          gCamera->setLens(D3DX_PI * 0.25f, w/h, 1.0f, 1000.0f);
  }
  
  void DisplacementMapDemo::updateScene(float dt)
  {
          mGfxStats->update(dt);
  
          gDInput->poll();
  
          // Prevent camera from getting too close to water
          if(gCamera->pos().y < 2.0f)
                  gCamera->pos().y = 2.0f;
  
          gCamera->update(dt, 0, 0);
          
  
          mWater->update(dt);
  }
  
  void DisplacementMapDemo::drawScene()
  {
          HR(gd3dDevice->BeginScene());
  
          mSky->draw();
  
          mWater->draw();
  
          mGfxStats->display();
  
          HR(gd3dDevice->EndScene());
  
          // Present the backbuffer.
          HR(gd3dDevice->Present(0, 0, 0, 0));
  }