// include the basic windows header files and the Direct3D header file
      #include <windows.h>
      #include <windowsx.h>
      #include <d3d9.h>
      #include <d3dx9.h>

      // define the screen resolution and keyboard macros
      #define SCREEN_WIDTH  1024
      #define SCREEN_HEIGHT 768
      #define KEY_DOWN(vk_code) ((GetAsyncKeyState(vk_code) & 0x8000) ? 1 : 0)
      #define KEY_UP(vk_code) ((GetAsyncKeyState(vk_code) & 0x8000) ? 0 : 1)

      // include the Direct3D Library file
      #pragma comment (lib, "d3d9.lib")
      #pragma comment (lib, "d3dx9.lib")

      // global declarations
      LPDIRECT3D9 d3d;    // the pointer to our Direct3D interface
      LPDIRECT3DDEVICE9 d3ddev;    // the pointer to the device class
      LPD3DXSPRITE d3dspt;    // the pointer to our Direct3D Sprite interface

      // sprite declarations
      LPDIRECT3DTEXTURE9 sprite1;    // the pointer to the sprite
      LPDIRECT3DTEXTURE9 sprite2;    // the pointer to the sprite
      LPDIRECT3DTEXTURE9 sprite3;    // the pointer to the sprite

      float x1a = 0;
      float x1b = 0;
      float x1c = 0;
      float y = 0;
      float velocidade1X = 1;
      float velocidade2X = 5;
      float velocidade3X = 10;

      // function prototypes
      void initD3D(HWND hWnd); // sets up and initializes Direct3D
      void render_frame(void); // renders a single frame
      void cleanD3D(void); // closes Direct3D and releases memory

      // the WindowProc function prototype
      LRESULT CALLBACK WindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);


      // the entry point for any Windows program
      int WINAPI WinMain(HINSTANCE hInstance,
                         HINSTANCE hPrevInstance,
                         LPSTR lpCmdLine,
                         int nCmdShow)
      {
          HWND hWnd;
          WNDCLASSEX wc;

          ZeroMemory(&wc, sizeof(WNDCLASSEX));

          wc.cbSize = sizeof(WNDCLASSEX);
          wc.style = CS_HREDRAW | CS_VREDRAW;
          wc.lpfnWndProc = (WNDPROC)WindowProc;
          wc.hInstance = hInstance;
          wc.hCursor = LoadCursor(NULL, IDC_ARROW);
          wc.lpszClassName = L"WindowClass1";

          RegisterClassEx(&wc);

          hWnd = CreateWindowEx(NULL,
                                L"WindowClass1",
                                L"Our Direct3D Program",
                                WS_EX_TOPMOST | WS_POPUP,
                                0, 0,
                                SCREEN_WIDTH, SCREEN_HEIGHT,
                                NULL,
                                NULL,
                                hInstance,
                                NULL);

          ShowWindow(hWnd, nCmdShow);

          // set up and initialize Direct3D
          initD3D(hWnd);

          // enter the main loop:

          MSG msg;

          while(TRUE)
          {
              DWORD starting_point = GetTickCount();

              if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
              {
                  if (msg.message == WM_QUIT)
                      break;

                  TranslateMessage(&msg);
                  DispatchMessage(&msg);
              }

              render_frame();

              // check the 'escape' key
              if(KEY_DOWN(VK_ESCAPE))
                  PostMessage(hWnd, WM_DESTROY, 0, 0);

              while ((GetTickCount() - starting_point) < 25);
          }

          // clean up DirectX and COM
          cleanD3D();

          return msg.wParam;
      }


      // this is the main message handler for the program
      LRESULT CALLBACK WindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
      {
          switch(message)
          {
              case WM_DESTROY:
                  {
                      PostQuitMessage(0);
                      return 0;
                  } break;
          }

          return DefWindowProc (hWnd, message, wParam, lParam);
      }


      // this function initializes and prepares Direct3D for use
      void initD3D(HWND hWnd)
      {
          d3d = Direct3DCreate9(D3D_SDK_VERSION);

          D3DPRESENT_PARAMETERS d3dpp;

          ZeroMemory(&d3dpp, sizeof(d3dpp));
          d3dpp.Windowed = FALSE;
          d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
          d3dpp.hDeviceWindow = hWnd;
          d3dpp.BackBufferFormat = D3DFMT_X8R8G8B8;
          d3dpp.BackBufferWidth = SCREEN_WIDTH;
          d3dpp.BackBufferHeight = SCREEN_HEIGHT;

          // create a device class using this information and the info from the d3dpp stuct
          d3d->CreateDevice(D3DADAPTER_DEFAULT,
                            D3DDEVTYPE_HAL,
                            hWnd,
                            D3DCREATE_SOFTWARE_VERTEXPROCESSING,
                            &d3dpp,
                            &d3ddev);

          D3DXCreateSprite(d3ddev, &d3dspt);    // create the Direct3D Sprite object

        

          D3DXCreateTextureFromFile(d3ddev, L"img1.png", &sprite1);
        D3DXCreateTextureFromFile(d3ddev, L"img2.png", &sprite2);
        D3DXCreateTextureFromFile(d3ddev, L"img3.png", &sprite3);

          return;
      }


      // this is the function used to render a single frame
      void render_frame(void)
      {
          // clear the window to a deep blue
          d3ddev->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);

          d3ddev->BeginScene();    // begins the 3D scene

          d3dspt->Begin(NULL);    // begin sprite drawing

          // draw the sprite
          D3DXVECTOR3 center(0.0f, 0.0f, 0.0f);
          D3DXVECTOR3 position1a(x1a, y, 0.0f);
        D3DXVECTOR3 position2a(x1a + SCREEN_WIDTH, y, 0.0f);

        x1a -= velocidade2X;

        if(position2a.x <= 0)
          x1a = 0;

        d3dspt->Draw(
          sprite3, 
          NULL, 
          ¢er, 
          &position1a, 
          D3DCOLOR_XRGB(255, 255, 255));

          d3dspt->Draw(
          sprite3, 
          NULL, 
          ¢er, 
          &position2a, 
          D3DCOLOR_XRGB(255, 255, 255));


          d3dspt->End();    // end sprite drawing

          d3ddev->EndScene();    // ends the 3D scene

          d3ddev->Present(NULL, NULL, NULL, NULL);

          return;
      }


      // this is the function that cleans up Direct3D and COM
      void cleanD3D(void)
      {
          sprite1->Release();
        sprite2->Release();
        sprite3->Release();
          d3ddev->Release();
          d3d->Release();

          return;
      }