//=============================================================================
  // PointLightDemo.cpp by Frank Luna (C) 2005 All Rights Reserved.
  //
  // Demonstrates an animated point light.
  //
  // Controls: Use mouse to orbit and zoom; use the 'W' and 'S' keys to 
  //           alter the height of the camera.
  //=============================================================================
  
  include <d3dApp.h>
  include <DirectInput.h>
  include <crtdbg.h>
  include <GfxStats.h>
  include <list>
  include <Vertex.h>
  
  class PointLightDemo : public D3DApp
  {
  public:
          PointLightDemo(HINSTANCE hInstance, std::string winCaption, D3DDEVTYPE devType, DWORD requestedVP);
          ~PointLightDemo();
  
          bool checkDeviceCaps();
          void onLostDevice();
          void onResetDevice();
          void updateScene(float dt);
          void drawScene();
  
          // Helper methods
          void buildGeoBuffers();
          void buildFX();
          void buildViewMtx();
          void buildProjMtx();
  
          void drawGrid();
          void drawCylinders();
          void drawSpheres();
  
  private:
          GfxStats* mGfxStats;
  
          DWORD mNumGridVertices;
          DWORD mNumGridTriangles;
  
          ID3DXMesh* mCylinder;
          ID3DXMesh* mSphere;
  
          IDirect3DVertexBuffer9* mVB;
          IDirect3DIndexBuffer9*  mIB;
  
          ID3DXEffect* mFX;
          D3DXHANDLE   mhTech;
          D3DXHANDLE   mhWVP;
          D3DXHANDLE   mhWorldInvTrans;
          D3DXHANDLE   mhAmbientLight;
          D3DXHANDLE   mhDiffuseLight;
          D3DXHANDLE   mhSpecLight;
          D3DXHANDLE   mhLightPosW;
          D3DXHANDLE   mhAttenuation012;
          D3DXHANDLE   mhAmbientMtrl;
          D3DXHANDLE   mhDiffuseMtrl;
          D3DXHANDLE   mhSpecMtrl;
          D3DXHANDLE   mhSpecPower;
          D3DXHANDLE   mhEyePos;
          D3DXHANDLE   mhWorld;
  
          D3DXCOLOR   mAmbientLight;
          D3DXCOLOR   mDiffuseLight;
          D3DXCOLOR   mSpecLight;
          D3DXVECTOR3 mLightPosW;
          D3DXVECTOR3 mAttenuation012;
  
          Mtrl  mGridMtrl;
          Mtrl  mCylinderMtrl;
          Mtrl  mSphereMtrl;
  
          float mCameraRotationY;
          float mCameraRadius;
          float mCameraHeight;
  
          D3DXMATRIX mView;
          D3DXMATRIX mProj;
  };
  
  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
  
          PointLightDemo app(hInstance, "Point Light Demo", D3DDEVTYPE_HAL, D3DCREATE_HARDWARE_VERTEXPROCESSING);
          gd3dApp = &app;
  
          DirectInput di(DISCL_NONEXCLUSIVE|DISCL_FOREGROUND, DISCL_NONEXCLUSIVE|DISCL_FOREGROUND);
          gDInput = &di;
  
      return gd3dApp->run();
  }
  
  PointLightDemo::PointLightDemo(HINSTANCE hInstance, std::string winCaption, D3DDEVTYPE devType, DWORD requestedVP)
  : D3DApp(hInstance, winCaption, devType, requestedVP)
  {
          if(!checkDeviceCaps())
          {
                  MessageBox(0, "checkDeviceCaps() Failed", 0, 0);
                  PostQuitMessage(0);
          }
  
          mGfxStats = new GfxStats();
  
          mCameraRadius    = 50.0f;
          mCameraRotationY = 1.2 * D3DX_PI;
          mCameraHeight    = 20.0f;
  
          mAmbientLight   = 0.4f*WHITE;
          mDiffuseLight   = WHITE;
          mSpecLight      = WHITE;
          mLightPosW      = D3DXVECTOR3(0.0f, 3.0f, 0.0f);
          mAttenuation012 = D3DXVECTOR3(1.0f, 0.0f, 0.0f);
  
          mGridMtrl     = Mtrl(BLUE, BLUE, WHITE, 16.0f);
          mCylinderMtrl = Mtrl(RED, RED, WHITE, 8.0f);
          mSphereMtrl   = Mtrl(GREEN, GREEN, WHITE, 8.0f);
  
          HR(D3DXCreateCylinder(gd3dDevice, 1.0f, 1.0f, 6.0f, 20, 20, &mCylinder, 0));
          HR(D3DXCreateSphere(gd3dDevice, 1.0f, 20, 20, &mSphere, 0));
  
          buildGeoBuffers();
          buildFX();
  
          // If you look at the drawCylinders and drawSpheres functions, you see
          // that we draw 14 cylinders and 14 spheres.
          int numCylVerts    = mCylinder->GetNumVertices() * 14;
          int numSphereVerts = mSphere->GetNumVertices()   * 14;
          int numCylTris     = mCylinder->GetNumFaces()    * 14;
          int numSphereTris  = mSphere->GetNumFaces()      * 14;
  
          mGfxStats->addVertices(mNumGridVertices);
          mGfxStats->addVertices(numCylVerts);
          mGfxStats->addVertices(numSphereVerts);
          mGfxStats->addTriangles(mNumGridTriangles);
          mGfxStats->addTriangles(numCylTris);
          mGfxStats->addTriangles(numSphereTris);
  
          onResetDevice();
  
          InitAllVertexDeclarations();
  }
  
  PointLightDemo::~PointLightDemo()
  {
          delete mGfxStats;
          ReleaseCOM(mVB);
          ReleaseCOM(mIB);
          ReleaseCOM(mFX);
          ReleaseCOM(mCylinder);
          ReleaseCOM(mSphere);
  
          DestroyAllVertexDeclarations();
  }
  
  bool PointLightDemo::checkDeviceCaps()
  {
          D3DCAPS9 caps;
          HR(gd3dDevice->GetDeviceCaps(&caps));
  
          // Check for vertex shader version 2.0 support.
          if( caps.VertexShaderVersion < D3DVS_VERSION(2, 0) )
                  return false;
  
          // Check for pixel shader version 2.0 support.
          if( caps.PixelShaderVersion < D3DPS_VERSION(2, 0) )
                  return false;
  
          return true;
  }
  
  void PointLightDemo::onLostDevice()
  {
          mGfxStats->onLostDevice();
          HR(mFX->OnLostDevice());
  }
  
  void PointLightDemo::onResetDevice()
  {
          mGfxStats->onResetDevice();
          HR(mFX->OnResetDevice());
  
          // The aspect ratio depends on the backbuffer dimensions, which can 
          // possibly change after a reset.  So rebuild the projection matrix.
          buildProjMtx();
  }
  
  void PointLightDemo::updateScene(float dt)
  {
          mGfxStats->update(dt);
  
          // Get snapshot of input devices.
          gDInput->poll();
  
          // Check input.
          if( gDInput->keyDown(DIK_W) )         
                  mCameraHeight   += 25.0f * dt;
          if( gDInput->keyDown(DIK_S) )         
                  mCameraHeight   -= 25.0f * dt;
  
          // Divide to make mouse less sensitive. 
          mCameraRotationY += gDInput->mouseDX() / 100.0f;
          mCameraRadius    += gDInput->mouseDY() / 25.0f;
  
          // If we rotate over 360 degrees, just roll back to 0
          if( fabsf(mCameraRotationY) >= 2.0f * D3DX_PI ) 
                  mCameraRotationY = 0.0f;
  
          // Don't let radius get too small.
          if( mCameraRadius < 5.0f )
                  mCameraRadius = 5.0f;
  
          // The camera position/orientation relative to world space can 
          // change every frame based on input, so we need to rebuild the
          // view matrix every frame with the latest changes.
          buildViewMtx();
  
          // Oscillate the light up and down the world z-axis.
          static float theta = 0.0f;
          theta += dt;
  
          // Reset the angle every period so that theta
          // doesn't get too big.
          if(theta >= 2.0f*D3DX_PI)
                  theta = 0.0f;
  
          mLightPosW.z = 25.0f*sinf(theta);
  }
  
  void PointLightDemo::drawScene()
  {
          // Clear the backbuffer and depth buffer.
          HR(gd3dDevice->Clear(0, 0, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER, 0xffffffff, 1.0f, 0));
  
          HR(gd3dDevice->BeginScene());
  
          // Setup the rendering FX
          HR(mFX->SetValue(mhAmbientLight, &mAmbientLight, sizeof(D3DXCOLOR)));
          HR(mFX->SetValue(mhDiffuseLight, &mDiffuseLight, sizeof(D3DXCOLOR)));
          HR(mFX->SetValue(mhSpecLight, &mSpecLight, sizeof(D3DXCOLOR)));
          HR(mFX->SetValue(mhLightPosW, &mLightPosW, sizeof(D3DXVECTOR3)));
          HR(mFX->SetValue(mhAttenuation012, &mAttenuation012, sizeof(D3DXVECTOR3)));
  
          // Begin passes.
          UINT numPasses = 0;
          HR(mFX->Begin(&numPasses, 0));
          for(UINT i = 0; i < numPasses; ++i)
          {
                  HR(mFX->BeginPass(i));
  
                  drawGrid();
                  drawCylinders();
                  drawSpheres();
  
                  HR(mFX->EndPass());
          }
          HR(mFX->End());
  
          
          mGfxStats->display();
  
          HR(gd3dDevice->EndScene());
  
          // Present the backbuffer.
          HR(gd3dDevice->Present(0, 0, 0, 0));
  }
   
  void PointLightDemo::buildGeoBuffers()
  {
          std::vector<D3DXVECTOR3> verts;
          std::vector<DWORD> indices;
  
          GenTriGrid(100, 100, 1.0f, 1.0f, 
                  D3DXVECTOR3(0.0f, 0.0f, 0.0f), verts, indices);
  
          // Save vertex count and triangle count for DrawIndexedPrimitive arguments.
          mNumGridVertices  = 100*100;
          mNumGridTriangles = 99*99*2;
  
          // Obtain a pointer to a new vertex buffer.
          HR(gd3dDevice->CreateVertexBuffer(mNumGridVertices * sizeof(VertexPN), 
                  D3DUSAGE_WRITEONLY,        0, D3DPOOL_MANAGED, &mVB, 0));
  
          // Now lock it to obtain a pointer to its internal data, and write the
          // grid's vertex data.
          VertexPN* v = 0;
          HR(mVB->Lock(0, 0, (void**)&v, 0));
  
          for(DWORD i = 0; i < mNumGridVertices; ++i)
          {
                  v[i].pos = verts[i];
                  v[i].normal = D3DXVECTOR3(0.0f, 1.0f, 0.0f);
          }
  
          HR(mVB->Unlock());
  
          // Obtain a pointer to a new index buffer.
          HR(gd3dDevice->CreateIndexBuffer(mNumGridTriangles*3*sizeof(WORD), D3DUSAGE_WRITEONLY,
                  D3DFMT_INDEX16, D3DPOOL_MANAGED, &mIB, 0));
  
          // Now lock it to obtain a pointer to its internal data, and write the
          // grid's index data.
  
          WORD* k = 0;
          HR(mIB->Lock(0, 0, (void**)&k, 0));
  
          for(DWORD i = 0; i < mNumGridTriangles*3; ++i)
                  k[i] = (WORD)indices[i];
  
          HR(mIB->Unlock());
  }
  
  void PointLightDemo::buildFX()
  {
          // Create the FX from a .fx file.
          ID3DXBuffer* errors = 0;
          HR(D3DXCreateEffectFromFile(gd3dDevice, "pointlight.fx", 
                  0, 0, D3DXSHADER_DEBUG, 0, &mFX, &errors));
          if( errors )
                  MessageBox(0, (char*)errors->GetBufferPointer(), 0, 0);
  
          // Obtain handles.
          mhTech           = mFX->GetTechniqueByName("PointLightTech");
          mhWVP            = mFX->GetParameterByName(0, "gWVP");
          mhWorldInvTrans  = mFX->GetParameterByName(0, "gWorldInvTrans");
          mhEyePos         = mFX->GetParameterByName(0, "gEyePosW");
          mhWorld          = mFX->GetParameterByName(0, "gWorld");
          mhAmbientLight   = mFX->GetParameterByName(0, "gAmbientLight");
          mhDiffuseLight   = mFX->GetParameterByName(0, "gDiffuseLight");
          mhSpecLight      = mFX->GetParameterByName(0, "gSpecLight");
          mhLightPosW      = mFX->GetParameterByName(0, "gLightPosW");
          mhAttenuation012 = mFX->GetParameterByName(0, "gAttenuation012");
          mhAmbientMtrl    = mFX->GetParameterByName(0, "gAmbientMtrl");
          mhDiffuseMtrl    = mFX->GetParameterByName(0, "gDiffuseMtrl");
          mhSpecMtrl       = mFX->GetParameterByName(0, "gSpecMtrl");
          mhSpecPower      = mFX->GetParameterByName(0, "gSpecPower");
  }
  
  void PointLightDemo::buildViewMtx()
  {
          float x = mCameraRadius * cosf(mCameraRotationY);
          float z = mCameraRadius * sinf(mCameraRotationY);
          D3DXVECTOR3 pos(x, mCameraHeight, z);
          D3DXVECTOR3 target(0.0f, 0.0f, 0.0f);
          D3DXVECTOR3 up(0.0f, 1.0f, 0.0f);
          D3DXMatrixLookAtLH(&mView, &pos, &target, &up);
  
          HR(mFX->SetValue(mhEyePos, &pos, sizeof(D3DXVECTOR3)));
  }
  
  void PointLightDemo::buildProjMtx()
  {
          float w = (float)md3dPP.BackBufferWidth;
          float h = (float)md3dPP.BackBufferHeight;
          D3DXMatrixPerspectiveFovLH(&mProj, D3DX_PI * 0.25f, w/h, 1.0f, 5000.0f);
  }
  
  void PointLightDemo::drawGrid()
  {
          HR(gd3dDevice->SetStreamSource(0, mVB, 0, sizeof(VertexPN)));
          HR(gd3dDevice->SetIndices(mIB));
          HR(gd3dDevice->SetVertexDeclaration(VertexPN::Decl));
  
          D3DXMATRIX W, WIT;
          D3DXMatrixIdentity(&W);
          D3DXMatrixInverse(&WIT, 0, &W);
          D3DXMatrixTranspose(&WIT, &WIT);
          HR(mFX->SetMatrix(mhWorld, &W));
          HR(mFX->SetMatrix(mhWVP, &(W*mView*mProj)));
          HR(mFX->SetMatrix(mhWorldInvTrans, &WIT));
  
          HR(mFX->SetValue(mhAmbientMtrl, &mGridMtrl.ambient, sizeof(D3DXCOLOR)));
          HR(mFX->SetValue(mhDiffuseMtrl, &mGridMtrl.diffuse, sizeof(D3DXCOLOR)));
          HR(mFX->SetValue(mhSpecMtrl, &mGridMtrl.spec, sizeof(D3DXCOLOR)));
          HR(mFX->SetFloat(mhSpecPower, mGridMtrl.specPower));
  
          HR(mFX->CommitChanges());
          HR(gd3dDevice->DrawIndexedPrimitive(D3DPT_TRIANGLELIST, 0, 0, mNumGridVertices, 0, mNumGridTriangles));
  }
  
  void PointLightDemo::drawCylinders()
  {
          D3DXMATRIX T, R, W, WIT;
  
          D3DXMatrixRotationX(&R, D3DX_PI*0.5f);
  
          HR(mFX->SetValue(mhAmbientMtrl, &mCylinderMtrl.ambient, sizeof(D3DXCOLOR)));
          HR(mFX->SetValue(mhDiffuseMtrl, &mCylinderMtrl.diffuse, sizeof(D3DXCOLOR)));
          HR(mFX->SetValue(mhSpecMtrl, &mCylinderMtrl.spec, sizeof(D3DXCOLOR)));
          HR(mFX->SetFloat(mhSpecPower, mCylinderMtrl.specPower));
          for(int z = -30; z <= 30; z+= 10)
          {
                  D3DXMatrixTranslation(&T, -10.0f, 3.0f, (float)z);
                  W = R*T;
                  D3DXMatrixInverse(&WIT, 0, &W);
                  D3DXMatrixTranspose(&WIT, &WIT);
  
                  HR(mFX->SetMatrix(mhWVP, &(W*mView*mProj)));
                  HR(mFX->SetMatrix(mhWorld, &W));
                  HR(mFX->SetMatrix(mhWorldInvTrans, &WIT));
                  HR(mFX->CommitChanges());
                  HR(mCylinder->DrawSubset(0));
  
                  D3DXMatrixTranslation(&T, 10.0f, 3.0f, (float)z);
                  W = R*T;
                  D3DXMatrixInverse(&WIT, 0, &W);
                  D3DXMatrixTranspose(&WIT, &WIT);
  
                  HR(mFX->SetMatrix(mhWVP, &(W*mView*mProj)));
                  HR(mFX->SetMatrix(mhWorld, &W));
                  HR(mFX->SetMatrix(mhWorldInvTrans, &WIT));
                  HR(mFX->CommitChanges());
                  HR(mCylinder->DrawSubset(0));
          }
  }
  
  void PointLightDemo::drawSpheres()
  {
          D3DXMATRIX W, WIT;
  
          HR(mFX->SetValue(mhAmbientMtrl, &mSphereMtrl.ambient, sizeof(D3DXCOLOR)));
          HR(mFX->SetValue(mhDiffuseMtrl, &mSphereMtrl.diffuse, sizeof(D3DXCOLOR)));
          HR(mFX->SetValue(mhSpecMtrl, &mSphereMtrl.spec, sizeof(D3DXCOLOR)));
          HR(mFX->SetFloat(mhSpecPower, mSphereMtrl.specPower));
          for(int z = -30; z <= 30; z+= 10)
          {
                  D3DXMatrixTranslation(&W, -10.0f, 7.5f, (float)z);
                  D3DXMatrixInverse(&WIT, 0, &W);
                  D3DXMatrixTranspose(&WIT, &WIT);
  
                  HR(mFX->SetMatrix(mhWVP, &(W*mView*mProj)));
                  HR(mFX->SetMatrix(mhWorld, &W));
                  HR(mFX->SetMatrix(mhWorldInvTrans, &WIT));
                  HR(mFX->CommitChanges());
                  HR(mSphere->DrawSubset(0));
  
                  D3DXMatrixTranslation(&W, 10.0f, 7.5f, (float)z);
                  D3DXMatrixInverse(&WIT, 0, &W);
                  D3DXMatrixTranspose(&WIT, &WIT);
  
                  HR(mFX->SetMatrix(mhWVP, &(W*mView*mProj)));
                  HR(mFX->SetMatrix(mhWorld, &W));
                  HR(mFX->SetMatrix(mhWorldInvTrans, &WIT));
                  HR(mFX->CommitChanges());
                  HR(mSphere->DrawSubset(0));
          }
  }