cropcircles.cpp

游戏编程源码

//-----------------------------------------------------------------
// Crop Circles Application
// C++ Source - CropCircles.cpp
//-----------------------------------------------------------------

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

//-----------------------------------------------------------------
// Game Engine Functions
//-----------------------------------------------------------------
BOOL GameInitialize(HINSTANCE hInstance)
{
  // Create the game engine
  g_pGame = new GameEngine(hInstance, TEXT("Crop Circles"),
    TEXT("Crop Circles"), IDI_CROPCIRCLES, IDI_CROPCIRCLES_SM);
  if (g_pGame == NULL)
    return FALSE;
  
  // Set the frame rate (yes, it's deliberately slow)
  g_pGame->SetFrameRate(1);

  return TRUE;
}

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

  // Set the position and size of the initial crop circle
  g_rcRectangle.left = g_pGame->GetWidth() * 2 / 5;
  g_rcRectangle.top = g_pGame->GetHeight() * 2 / 5;
  g_rcRectangle.right = g_rcRectangle.left + g_pGame->GetWidth() / 10;
  g_rcRectangle.bottom = g_rcRectangle.top + g_pGame->GetWidth() / 10;
}

void GameEnd()
{
  // Cleanup the game engine
  delete g_pGame;
}

void GameActivate(HWND hWindow)
{
}

void GameDeactivate(HWND hWindow)
{
}

void GamePaint(HDC hDC)
{
  // Draw a dark yellow field as the background for the crop circles
  RECT    rect;
  GetClientRect(g_pGame->GetWindow(), &rect);
  HBRUSH hBrush = CreateSolidBrush(RGB(128, 128, 0));   // dark yellow color
  FillRect(hDC, &rect, hBrush);
  DeleteObject(hBrush);
}

void GameCycle()
{
  RECT        rect;
  HDC         hDC;
  HWND        hWindow = g_pGame->GetWindow();

  // Remember the location of the last crop circle
  int iXLast = g_rcRectangle.left + 
    (g_rcRectangle.right - g_rcRectangle.left) / 2;
  int iYLast = g_rcRectangle.top + 
    (g_rcRectangle.bottom - g_rcRectangle.top) / 2;

  // Randomly alter the size and position of the new crop circle
  GetClientRect(g_pGame->GetWindow(), &rect);
  int iInflation = (rand() % 17) - 8; // increase or decrease size by up to 8
  InflateRect(&g_rcRectangle, iInflation, iInflation);
  OffsetRect(&g_rcRectangle, 
    rand() % (rect.right - rect.left) - g_rcRectangle.left,
    rand() % (rect.bottom - rect.top) - g_rcRectangle.top);

  // Draw a line to the new crop circle
  hDC = GetDC(hWindow);
  HPEN hPen = CreatePen(PS_SOLID, 5, RGB(192, 192, 0)); // light yellow color
  SelectObject(hDC, hPen);
  MoveToEx(hDC, iXLast, iYLast, NULL);
  LineTo(hDC,
    g_rcRectangle.left + (g_rcRectangle.right - g_rcRectangle.left) / 2,
    g_rcRectangle.top + (g_rcRectangle.bottom - g_rcRectangle.top) / 2);

  // Draw the new crop circle
  HBRUSH hBrush = CreateSolidBrush(RGB(192, 192, 0));   // lighter yellow color
  SelectObject(hDC, hBrush);
  Ellipse(hDC, g_rcRectangle.left, g_rcRectangle.top, 
    g_rcRectangle.right, g_rcRectangle.bottom);
  ReleaseDC(hWindow, hDC);
  DeleteObject(hBrush);
  DeleteObject(hPen);
}