Code:
#include "stdafx.h"
#include "Week 7 GDI.h"
#define MAX_LOADSTRING 100
// Global Variables:
HINSTANCE hInst; // current instance
TCHAR szTitle[MAX_LOADSTRING]; // The title bar text
TCHAR szWindowClass[MAX_LOADSTRING]; // the main window class name
// More global stuff
UINT ID_TIMER = 1;
UINT TIMER_DELAY = 30;
const int BALL_MOVE_DELTA = 2;
typedef struct _BALLINFO
{
int width;
int height;
int x;
int y;
int dx;
int dy;
}BALLINFO;
BALLINFO g_ballInfo;
HGDIOBJ g_hbmBall = NULL;
HGDIOBJ g_hbmMask = NULL;
// Forward declarations of functions included in this code module:
ATOM MyRegisterClass(HINSTANCE hInstance);
BOOL InitInstance(HINSTANCE, int);
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
INT_PTR CALLBACK About(HWND, UINT, WPARAM, LPARAM);
int APIENTRY _tWinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPTSTR lpCmdLine,
int nCmdShow)
{
UNREFERENCED_PARAMETER(hPrevInstance);
UNREFERENCED_PARAMETER(lpCmdLine);
// TODO: Place code here.
MSG msg;
HACCEL hAccelTable;
// Initialize global strings
LoadString(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING);
LoadString(hInstance, IDC_WEEK7GDI, szWindowClass, MAX_LOADSTRING);
MyRegisterClass(hInstance);
// Perform application initialization:
if (!InitInstance (hInstance, nCmdShow))
{
return FALSE;
}
hAccelTable = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDC_WEEK7GDI));
// Main message loop:
while (GetMessage(&msg, NULL, 0, 0))
{
if (!TranslateAccelerator(msg.hwnd, hAccelTable, &msg))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}
return (int) msg.wParam;
}
//
// FUNCTION: MyRegisterClass()
//
// PURPOSE: Registers the window class.
//
// COMMENTS:
//
// This function and its usage are only necessary if you want this code
// to be compatible with Win32 systems prior to the 'RegisterClassEx'
// function that was added to Windows 95. It is important to call this function
// so that the application will get 'well formed' small icons associated
// with it.
//
ATOM MyRegisterClass(HINSTANCE hInstance)
{
WNDCLASSEX wcex;
wcex.cbSize = sizeof(WNDCLASSEX);
wcex.style = CS_HREDRAW | CS_VREDRAW;
wcex.lpfnWndProc = WndProc;
wcex.cbClsExtra = 0;
wcex.cbWndExtra = 0;
wcex.hInstance = hInstance;
wcex.hIcon = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_WEEK7GDI));
wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
wcex.lpszMenuName = MAKEINTRESOURCE(IDC_WEEK7GDI);
wcex.lpszClassName = szWindowClass;
wcex.hIconSm = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_SMALL));
return RegisterClassEx(&wcex);
}
//
// FUNCTION: InitInstance(HINSTANCE, int)
//
// PURPOSE: Saves instance handle and creates main window
//
// COMMENTS:
//
// In this function, we save the instance handle in a global variable and
// create and display the main program window.
//
BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{
HWND hWnd;
hInst = hInstance; // Store instance handle in our global variable
hWnd = CreateWindow(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
10, 10, 320, 240, NULL, NULL, hInstance, NULL);
if (!hWnd)
{
return FALSE;
}
ShowWindow(hWnd, nCmdShow);
UpdateWindow(hWnd);
return TRUE;
}
// Function for the ball handling
HGDIOBJ CreateBitmapMask(HGDIOBJ hbmColour, COLORREF crTransparent)
{
HDC hdcMem, hdcMem2;
HGDIOBJ hbmMask;
BITMAP bm;
GetObject(hbmColour, sizeof(BITMAP), &bm);
hbmMask = CreateBitmap(bm.bmWidth, bm.bmHeight, 1, 1, NULL);
// create memory device
hdcMem = CreateCompatibleDC(0);
hdcMem2 = CreateCompatibleDC(0);
SelectObject(hdcMem, hbmColour);
SelectObject(hdcMem2, hbmMask);
SetBkColor(hdcMem, crTransparent);
BitBlt(hdcMem2, 0, 0, bm.bmWidth, bm.bmHeight, hdcMem, 0, 0, SRCCOPY);
BitBlt(hdcMem, 0, 0, bm.bmWidth, bm.bmHeight, hdcMem, 0, 0, SRCINVERT);
DeleteDC(hdcMem);
DeleteDC(hdcMem2);
return hbmMask;
}
// draw the ball
void DrawBall(HDC hdc, RECT* prc)
{
HDC hdcBuffer = CreateCompatibleDC(hdc);
HGDIOBJ hbmBuffer = CreateCompatibleBitmap(hdc, prc->right, prc->bottom);
HGDIOBJ hbmOldBuffer = SelectObject(hdcBuffer, hbmBuffer);
HDC hdcMem = CreateCompatibleDC(hdc);
HGDIOBJ hbmOld = SelectObject(hdcMem, g_hbmMask);
// clear the drawing area (fill with white)
FillRect(hdcBuffer, prc, (HBRUSH)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);
}
// update the ball location
void UpdateBall(RECT* prc)
{
g_ballInfo.x += g_ballInfo.dx;
g_ballInfo.y += g_ballInfo.dy;
//hit left edge?
if(g_ballInfo.x<0)
{
g_ballInfo.x = 0;
//set direction as right
g_ballInfo.dx = BALL_MOVE_DELTA;
}
else
//hit right edge?
if(g_ballInfo.x + g_ballInfo.width > prc->right)
{
g_ballInfo.y = 0;
// set ball direction as down
g_ballInfo.dy = BALL_MOVE_DELTA;
}
else
//hit bottom edge?
if(g_ballInfo.y + g_ballInfo.height > prc->bottom)
{
g_ballInfo.y = prc->bottom - g_ballInfo.height;
// set dir as up
g_ballInfo.dy = -BALL_MOVE_DELTA;
}
}
//
// FUNCTION: WndProc(HWND, UINT, WPARAM, LPARAM)
//
// PURPOSE: Processes messages for the main window.
//
// WM_COMMAND - process the application menu
// WM_PAINT - Paint the main window
// WM_DESTROY - post a quit message and return
//
//
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
int wmId, wmEvent;
PAINTSTRUCT ps;
HDC hdc;
switch (message)
{
case WM_COMMAND:
wmId = LOWORD(wParam);
wmEvent = HIWORD(wParam);
// Parse the menu selections:
switch (wmId)
{
case IDM_ABOUT:
DialogBox(hInst, MAKEINTRESOURCE(IDD_ABOUTBOX), hWnd, About);
break;
case IDM_EXIT:
DestroyWindow(hWnd);
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
}
break;
//initiate Ball and start Timer when window is created
case WM_CREATE:
{
BITMAP bm;
// create a GDI object from our bitmap
g_hbmBall = LoadBitmap(GetModuleHandle(NULL), MAKEINTRESOURCE(IDB_BALL));
if(g_hbmBall == NULL)
MessageBox(hWnd, "Could not load the IDB_BALL!", "Error", MB_OK | MB_ICONEXCLAMATION);
//create a mask making black transparent
g_hbmMask = CreateBitmapMask(g_hbmBall, RGB(0, 0, 0));
if(g_hbmMask == NULL)
MessageBox(hWnd, "Could not create mask!", "Error", MB_OK | MB_ICONEXCLAMATION);
//Create a BITMAP object [bm] from our bitmap
GetObject(g_hbmBall, sizeof(bm), &bm);
//clear BALLINFO struct
ZeroMemory(&g_ballInfo, sizeof(g_ballInfo));
// set its parameters
g_ballInfo.width = bm.bmWidth;
g_ballInfo.height = bm.bmHeight;
g_ballInfo.dx = BALL_MOVE_DELTA;
g_ballInfo.dy = BALL_MOVE_DELTA;
// create a timer that have msg ID 'ID_TIMER'
if(SetTimer(hWnd, ID_TIMER, TIMER_DELAY, NULL) == 0)
MessageBox(hWnd, "Could not SetTimer()!", "Error", MB_OK | MB_ICONEXCLAMATION);
}
break;
case WM_PAINT:
hdc = BeginPaint(hWnd, &ps);
//draw ball in window
RECT rcClient;
GetClientRect(hWnd, &rcClient);
DrawBall(hdc, &rcClient);
EndPaint(hWnd, &ps);
break;
// handle TIMER events by updating [moving] Ball then re-drawing it
case WM_TIMER:
{
HDC hdc = GetDC(hWnd);
RECT rcClient;
GetClientRect(hWnd, &rcClient);
UpdateBall(&rcClient);
DrawBall(hdc, &rcClient);
ReleaseDC(hWnd, hdc);
}
// 'tidying up' when window closed to relase GDI ojects
case WM_DESTROY:
KillTimer(hWnd, ID_TIMER);
DeleteObject(g_hbmBall);
DeleteObject(g_hbmMask);
PostQuitMessage(0);
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
}
return 0;
}
// Message handler for about box.
INT_PTR CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
{
UNREFERENCED_PARAMETER(lParam);
switch (message)
{
case WM_INITDIALOG:
return (INT_PTR)TRUE;
case WM_COMMAND:
if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL)
{
EndDialog(hDlg, LOWORD(wParam));
return (INT_PTR)TRUE;
}
break;
}
return (INT_PTR)FALSE;
}
Animation Error
