henway.cpp

游戏编程源码

//-----------------------------------------------------------------
// Henway 2 Application
// C++ Source - Henway.cpp
//-----------------------------------------------------------------

//-----------------------------------------------------------------
// Include Files
//-----------------------------------------------------------------
#include "Henway.h"

//-----------------------------------------------------------------
// Game Engine Functions
//-----------------------------------------------------------------
BOOL GameInitialize(HINSTANCE hInstance)
{
  // Create the game engine
  g_pGame = new GameEngine(hInstance, TEXT("Henway 2"),
    TEXT("Henway 2"), IDI_HENWAY, IDI_HENWAY_SM, 465, 400);
  if (g_pGame == NULL)
    return FALSE;

  // Set the frame rate
  g_pGame->SetFrameRate(30);

  // Initialize the joystick
  g_pGame->InitJoystick();

  // Store the instance handle
  g_hInstance = hInstance;

  return TRUE;
}

void GameStart(HWND hWindow)
{
  // Seed the random number generator
  srand(GetTickCount());

  // Create the offscreen device context and bitmap
  g_hOffscreenDC = CreateCompatibleDC(GetDC(hWindow));
  g_hOffscreenBitmap = CreateCompatibleBitmap(GetDC(hWindow),
    g_pGame->GetWidth(), g_pGame->GetHeight());
  SelectObject(g_hOffscreenDC, g_hOffscreenBitmap);

  // Create and load the bitmaps
  HDC hDC = GetDC(hWindow);
  g_pHighwayBitmap = new Bitmap(hDC, IDB_HIGHWAY, g_hInstance);
  g_pChickenBitmap = new Bitmap(hDC, IDB_CHICKEN, g_hInstance);
  g_pCarBitmaps[0] = new Bitmap(hDC, IDB_CAR1, g_hInstance);
  g_pCarBitmaps[1] = new Bitmap(hDC, IDB_CAR2, g_hInstance);
  g_pCarBitmaps[2] = new Bitmap(hDC, IDB_CAR3, g_hInstance);
  g_pCarBitmaps[3] = new Bitmap(hDC, IDB_CAR4, g_hInstance);
  g_pChickenHeadBitmap = new Bitmap(hDC, IDB_CHICKENHEAD, g_hInstance);

  // Create the chicken and car sprites
  Sprite* pSprite;
  RECT    rcBounds = { 0, 0, 465, 400 };
  g_pChickenSprite = new Sprite(g_pChickenBitmap, rcBounds, BA_STOP);
  g_pChickenSprite->SetPosition(4, 175);
  g_pChickenSprite->SetVelocity(0, 0);
  g_pChickenSprite->SetZOrder(1);
  g_pGame->AddSprite(g_pChickenSprite);
  pSprite = new Sprite(g_pCarBitmaps[0], rcBounds, BA_WRAP);
  pSprite->SetPosition(70, 0);
  pSprite->SetVelocity(0, 7);
  pSprite->SetZOrder(2);
  g_pGame->AddSprite(pSprite);
  pSprite = new Sprite(g_pCarBitmaps[1], rcBounds, BA_WRAP);
  pSprite->SetPosition(160, 0);
  pSprite->SetVelocity(0, 3);
  pSprite->SetZOrder(2);
  g_pGame->AddSprite(pSprite);
  pSprite = new Sprite(g_pCarBitmaps[2], rcBounds, BA_WRAP);
  pSprite->SetPosition(239, 400);
  pSprite->SetVelocity(0, -5);
  pSprite->SetZOrder(2);
  g_pGame->AddSprite(pSprite);
  pSprite = new Sprite(g_pCarBitmaps[3], rcBounds, BA_WRAP);
  pSprite->SetPosition(329, 400);
  pSprite->SetVelocity(0, -10);
  pSprite->SetZOrder(2);
  g_pGame->AddSprite(pSprite);

  // Initialize the remaining global variables
  g_iInputDelay = 0;
  g_iNumLives = 3;
  g_iScore = 0;
  g_bGameOver = FALSE;

  // Play the background music
  g_pGame->PlayMIDISong(TEXT("Music.mid"));
}

void GameEnd()
{
  // Close the MIDI player for the background music
  g_pGame->CloseMIDIPlayer();

  // Cleanup the offscreen device context and bitmap
  DeleteObject(g_hOffscreenBitmap);
  DeleteDC(g_hOffscreenDC);  

  // Cleanup the bitmaps
  delete g_pHighwayBitmap;
  delete g_pChickenBitmap;
  for (int i = 0; i < 4; i++)
    delete g_pCarBitmaps[i];
  delete g_pChickenHeadBitmap;

  // Cleanup the sprites
  g_pGame->CleanupSprites();

  // Cleanup the game engine
  delete g_pGame;
}

void GameActivate(HWND hWindow)
{
  // Capture the joystick
  g_pGame->CaptureJoystick();

  // Resume the background music
  g_pGame->PlayMIDISong(TEXT(""), FALSE);
}

void GameDeactivate(HWND hWindow)
{
  // Release the joystick
  g_pGame->ReleaseJoystick();

  // Pause the background music
  g_pGame->PauseMIDISong();
}

void GamePaint(HDC hDC)
{
  // Draw the background highway
  g_pHighwayBitmap->Draw(hDC, 0, 0);

  // Draw the sprites
  g_pGame->DrawSprites(hDC);

  // Draw the number of remaining chicken lives
  for (int i = 0; i < g_iNumLives; i++)
    g_pChickenHeadBitmap->Draw(hDC,
      406 + (g_pChickenHeadBitmap->GetWidth() * i), 382, TRUE);
}

void GameCycle()
{
  if (!g_bGameOver)
  {
    // Play a random car sound randomly
    if (rand() % 100 == 0)
      if (rand() % 2 == 0)
        PlaySound((LPCSTR)IDW_CARHORN1, g_hInstance, SND_ASYNC | SND_RESOURCE);
      else
        PlaySound((LPCSTR)IDW_CARHORN2, g_hInstance, SND_ASYNC | SND_RESOURCE);

    // Update the sprites
    g_pGame->UpdateSprites();

    // Obtain a device context for repainting the game
    HWND  hWindow = g_pGame->GetWindow();
    HDC   hDC = GetDC(hWindow);

    // Paint the game to the offscreen device context
    GamePaint(g_hOffscreenDC);

    // Blit the offscreen bitmap to the game screen
    BitBlt(hDC, 0, 0, g_pGame->GetWidth(), g_pGame->GetHeight(),
      g_hOffscreenDC, 0, 0, SRCCOPY);

    // Cleanup
    ReleaseDC(hWindow, hDC);
  }
}

void HandleKeys()
{
  if (!g_bGameOver && (++g_iInputDelay > 2))
  {
    // Move the chicken based upon key presses
    if (GetAsyncKeyState(VK_LEFT) < 0)
      MoveChicken(-20, 0);
    else if (GetAsyncKeyState(VK_RIGHT) < 0)
      MoveChicken(20, 0);
    if (GetAsyncKeyState(VK_UP) < 0)
      MoveChicken(0, -20);
    else if (GetAsyncKeyState(VK_DOWN) < 0)
      MoveChicken(0, 20);

    // Reset the input delay
    g_iInputDelay = 0;
  }
}

void MouseButtonDown(int x, int y, BOOL bLeft)
{
  // Start a new game, if necessary
  if (g_bGameOver)
  {
    // Restart the background music
    g_pGame->PlayMIDISong();

    // Initialize the game variables
    g_iNumLives = 3;
    g_iScore = 0;
    g_bGameOver = FALSE;
  }
}

void MouseButtonUp(int x, int y, BOOL bLeft)
{
}

void MouseMove(int x, int y)
{
}

void HandleJoystick(JOYSTATE jsJoystickState)
{
  if (!g_bGameOver && (++g_iInputDelay > 2))
  {
    // Check horizontal movement
    if (jsJoystickState & JOY_LEFT)
        MoveChicken(-20, 0);
    else if (jsJoystickState & JOY_RIGHT)
        MoveChicken(20, 0);

    // Check vertical movement
    if (jsJoystickState & JOY_UP)
        MoveChicken(0, -20);
    else if (jsJoystickState & JOY_DOWN)
        MoveChicken(0, 20);

    // Reset the input delay
    g_iInputDelay = 0;
  }

  // Check the joystick button and start a new game, if necessary
  if (g_bGameOver && (jsJoystickState & JOY_FIRE1))
  {
    // Restart the background music
    g_pGame->PlayMIDISong();

    // Initialize the game variables
    g_iNumLives = 3;
    g_iScore = 0;
    g_bGameOver = FALSE;
  }
}

BOOL SpriteCollision(Sprite* pSpriteHitter, Sprite* pSpriteHittee)
{
  // See if the chicken was hit
  if (pSpriteHittee == g_pChickenSprite)
  {
    // Move the chicken back to the start
    g_pChickenSprite->SetPosition(4, 175);

    // See if the game is over
    if (--g_iNumLives > 0)
      // Play a sound for the chicken getting hit
      PlaySound((LPCSTR)IDW_SQUISH, g_hInstance, SND_ASYNC | SND_RESOURCE);
    else
    {
      // Play a sound for the game ending
      PlaySound((LPCSTR)IDW_GAMEOVER, g_hInstance, SND_ASYNC | SND_RESOURCE);

      // Display game over message
      TCHAR szText[64];
      wsprintf(szText, "Game Over! You scored %d points.", g_iScore);
      MessageBox(g_pGame->GetWindow(), szText, TEXT("Henway 2"), MB_OK);
      g_bGameOver = TRUE;

      // Pause the background music
      g_pGame->PauseMIDISong();
    }

    return FALSE;
  }

  return TRUE;
}

//-----------------------------------------------------------------
// Functions
//-----------------------------------------------------------------
void MoveChicken(int iXDistance, int iYDistance)
{
  // Play the "bok" chicken sound
  PlaySound((LPCSTR)IDW_BOK, g_hInstance, SND_ASYNC | SND_NOSTOP | SND_RESOURCE);

  // Move the chicken to its new position
  g_pChickenSprite->OffsetPosition(iXDistance, iYDistance);

  // See if the chicken made it across
  if (g_pChickenSprite->GetPosition().left > 400)
  {
    // Play a sound for the chicken making it safely across
    PlaySound((LPCSTR)IDW_CELEBRATE, g_hInstance, SND_ASYNC | SND_RESOURCE);

    // Move the chicken back to the start and add to the score
    g_pChickenSprite->SetPosition(4, 175);
    g_iScore += 150;
  }
}