Code:
#include <windows.h>
using namespace std;
void UpdateBall(RECT* prc);
void DrawBall(HDC hdc, RECT* prc);
/* Declare Windows procedure */
LRESULT CALLBACK WindowProcedure (HWND, UINT, WPARAM, LPARAM);
/* Make the class name into a global variable */
char szClassName[ ] = "WindowsApp";
int WINAPI WinMain (HINSTANCE hThisInstance,
HINSTANCE hPrevInstance,
LPSTR lpszArgument,
int nFunsterStil)
{
HWND hwnd; /* This is the handle for our window */
MSG messages; /* Here messages to the application are saved */
WNDCLASSEX wincl; /* Data structure for the windowclass */
/* The Window structure */
wincl.hInstance = hThisInstance;
wincl.lpszClassName = szClassName;
wincl.lpfnWndProc = WindowProcedure; /* This function is called by windows */
wincl.style = CS_DBLCLKS; /* Catch double-clicks */
wincl.cbSize = sizeof (WNDCLASSEX);
/* Use default icon and mouse-pointer */
wincl.hIcon = LoadIcon (NULL, IDI_APPLICATION);
wincl.hIconSm = LoadIcon (NULL, IDI_APPLICATION);
wincl.hCursor = LoadCursor (NULL, IDC_ARROW);
wincl.lpszMenuName = NULL; /* No menu */
wincl.cbClsExtra = 0; /* No extra bytes after the window class */
wincl.cbWndExtra = 0; /* structure or the window instance */
/* Use Windows's default color as the background of the window */
wincl.hbrBackground = (HBRUSH) COLOR_BACKGROUND;
/* Register the window class, and if it fails quit the program */
if (!RegisterClassEx (&wincl))
return 0;
/* The class is registered, let's create the program*/
hwnd = CreateWindowEx (
0, /* Extended possibilites for variation */
szClassName, /* Classname */
"Windows App", /* Title Text */
WS_OVERLAPPEDWINDOW, /* default window */
CW_USEDEFAULT, /* Windows decides the position */
CW_USEDEFAULT, /* where the window ends up on the screen */
544, /* The programs width */
375, /* and height in pixels */
HWND_DESKTOP, /* The window is a child-window to desktop */
NULL, /* No menu */
hThisInstance, /* Program Instance handler */
NULL /* No Window Creation data */
);
/* Make the window visible on the screen */
ShowWindow (hwnd, nFunsterStil);
/* Run the message loop. It will run until GetMessage() returns 0 */
while (GetMessage (&messages, NULL, 0, 0))
{
/* Translate virtual-key messages into character messages */
TranslateMessage(&messages);
/* Send message to WindowProcedure */
DispatchMessage(&messages);
}
/* The program return-value is 0 - The value that PostQuitMessage() gave */
return messages.wParam;
}
HBITMAP g_hbmBall = NULL;
const int BALL_MOVE_DELTA = 2;
const int ID_TIMER = 1;
typedef struct _BALLINFO
{
int width;
int height;
int x;
int y;
int dx;
int dy;
}BALLINFO;
BALLINFO g_ballInfo;
BITMAP bm;
GetObject(g_hbmBall, sizeof(bm), &bm);
ZeroMemory(&g_ballInfo, sizeof(g_ballInfo));
g_ballInfo.width = bm.bmWidth;
g_ballInfo.height = bm.bmHeight;
g_ballInfo.dx = BALL_MOVE_DELTA;
g_ballInfo.dy = BALL_MOVE_DELTA
const int ID_TIMER = 1;
ret = SetTimer(hwnd, ID_TIMER, 50, NULL);
if(ret == 0)
MessageBox(hwnd, "Could not SetTimer()!", "Error", MB_OK | MB_ICONEXCLAMATION);
/* This function is called by the Windows function DispatchMessage() */
LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message) /* handle the messages */
{
case WM_CREATE:
g_hbmBall = LoadBitmap(GetModuleHandle(NULL), MAKEINTRESOURCE(IDB_BALL));
if(g_hbmBall == NULL)
MessageBox(hwnd, "Could not load IDB_BALL!", "Error", MB_OK | MB_ICONEXCLAMATION);
ret = SetTimer(hwnd, ID_TIMER, 50, NULL);
if(ret == 0)
MessageBox(hwnd, "Could not SetTimer()!", "Error", MB_OK | MB_ICONEXCLAMATION);
break;
case WM_TIMER:
RECT rcClient;
HDC hdc = GetDC(hwnd);
GetClientRect(hwnd, &rcClient);
UpdateBall(&rcClient);
DrawBall(hdc, &rcClient);
ReleaseDC(hwnd, hdc);
break;
case WM_DESTROY:
KillTimer(hwnd, ID_TIMER);
PostQuitMessage (0); /* send a WM_QUIT to the message queue */
break;
default: /* for messages that we don't deal with */
return DefWindowProc (hwnd, message, wParam, lParam);
}
return 0;
}
//Function Definitions
void UpdateBall(RECT* prc)
{
g_ballInfo.x += g_ballInfo.dx;
g_ballInfo.y += g_ballInfo.dy;
if(g_ballInfo.x < 0)
{
g_ballInfo.x = 0;
g_ballInfo.dx = BALL_MOVE_DELTA;
}
else if(g_ballInfo.x + g_ballInfo.width > prc->right)
{
g_ballInfo.x = prc->right - g_ballInfo.width;
g_ballInfo.dx = -BALL_MOVE_DELTA;
}
if(g_ballInfo.y < 0)
{
g_ballInfo.y = 0;
g_ballInfo.dy = BALL_MOVE_DELTA;
}
else if(g_ballInfo.y + g_ballInfo.height > prc->bottom)
{
g_ballInfo.y = prc->bottom - g_ballInfo.height;
g_ballInfo.dy = -BALL_MOVE_DELTA;
}
}
void DrawBall(HDC hdc, RECT* prc)
{
HDC hdcBuffer = CreateCompatibleDC(hdc);
HBITMAP hbmBuffer = CreateCompatibleBitmap(hdc, prc->right, prc->bottom);
HBITMAP hbmOldBuffer = SelectObject(hdcBuffer, hbmBuffer);
HDC hdcMem = CreateCompatibleDC(hdc);
HBITMAP hbmOld = SelectObject(hdcMem, g_hbmMask);
FillRect(hdcBuffer, prc, GetStockObject(WHITE_BRUSH));
BitBlt(hdcBuffer, g_ballInfo.x, g_ballInfo.y, g_ballInfo.width, g_ballInfo.height, hdcMem, 0, 0, SRCAND);
SelectObject(hdcMem, g_hbmBall);
BitBlt(hdcBuffer, g_ballInfo.x, g_ballInfo.y, g_ballInfo.width, g_ballInfo.height, hdcMem, 0, 0, SRCPAINT);
BitBlt(hdc, 0, 0, prc->right, prc->bottom, hdcBuffer, 0, 0, SRCCOPY);
SelectObject(hdcMem, hbmOld);
DeleteDC(hdcMem);
SelectObject(hdcBuffer, hbmOldBuffer);
DeleteDC(hdcBuffer);
DeleteObject(hbmBuffer);
}