c++小球反弹运动

在窗口中显示一个小球，该球以45度角反弹直线运动，碰撞后依然45度运行

// experiment3.cpp : Defines the entry point for the application.
//

#include “stdafx.h“
#include “resource.h“

#define MAX_LOADSTRING 100

// Global Variables:
HINSTANCE hInst;								// current instance
TCHAR sztitle[MAX_LOADSTRING];								// The title bar text
TCHAR szWindowClass[MAX_LOADSTRING];								// The title bar text

// Foward declarations of functions included in this code module:
ATOM				MyRegisterClass（HINSTANCE hInstance）;
BOOL				InitInstance（HINSTANCE int）;
LRESULT CALLBACK	WndProc（HWND UINT WPARAM LPARAM）;
LRESULT CALLBACK	About（HWND UINT WPARAM LPARAM）;

int xcenter = 300;
int ycenter = 300;

int xmove = 5; 
int ymove = 5;

int APIENTRY WinMain（HINSTANCE hInstance
                     HINSTANCE hPrevInstance
                     LPSTR     lpCmdLine
                     int       nCmdShow）
{
 	// TODO: Place code here.
	MSG msg;
	HACCEL hAccelTable;

	// Initialize global strings
	LoadString（hInstance IDS_APP_title sztitle MAX_LOADSTRING）;
	LoadString（hInstance IDC_EXPERIMENT3 szWindowClass MAX_LOADSTRING）;
	MyRegisterClass（hInstance）;

	// Perform application initialization:
	if （!InitInstance （hInstance nCmdShow）） 
	{
		return FALSE;
	}

	hAccelTable = LoadAccelerators（hInstance （LPCTSTR）IDC_EXPERIMENT3）;

  

	// Main message loop:
	while （GetMessage（&msg NULL 0 0）） 
	{
		if （!TranslateAccelerator（msg.hwnd hAccelTable &msg）） 
		{
			TranslateMessage（&msg）;
			DispatchMessage（&msg）;
		}
	}

	return msg.wParam;
}



//
//  FUNCTION: MyRegisterClass（）
//
//  PURPOSE: Registers the window class.
//
//  COMMENTS:
//
//    This function and its usage is 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）WndProc;
	wcex.cbClsExtra		= 0;
	wcex.cbWndExtra		= 0;
	wcex.hInstance		= hInstance;
	wcex.hIcon			= LoadIcon（hInstance （LPCTSTR）IDI_EXPERIMENT3）;
	wcex.hCursor		= LoadCursor（NULL IDC_ARROW）;
	wcex.hbrBackground	= （HBRUSH）（COLOR_WINDOW+1）;
	wcex.lpszMenuName	= （LPCSTR）IDC_EXPERIMENT3;
	wcex.lpszClassName	= szWindowClass;
	wcex.hIconSm		= LoadIcon（wcex.hInstance （LPCTSTR）IDI_SMALL）;

	return RegisterClassEx（&wcex）;
}

//
//   FUNCTION: InitInstance（HANDLE 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 

 属性            大小     日期    时间   名称
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     文件     159843  2012-03-28 09:13  experiment3\experiment3\Debug\experiment3.exe

     文件     195224  2012-03-28 09:13  experiment3\experiment3\Debug\experiment3.ilk

     文件       9295  2012-03-28 09:13  experiment3\experiment3\Debug\experiment3.obj

     文件    1951796  2012-03-27 23:22  experiment3\experiment3\Debug\experiment3.pch

     文件     459776  2012-03-28 09:13  experiment3\experiment3\Debug\experiment3.pdb

     文件       2152  2012-03-27 23:22  experiment3\experiment3\Debug\experiment3.res

     文件      55282  2012-03-27 23:22  experiment3\experiment3\Debug\StdAfx.obj

     文件      91136  2012-03-28 09:13  experiment3\experiment3\Debug\vc60.idb

     文件     176128  2012-03-28 09:13  experiment3\experiment3\Debug\vc60.pdb

     文件       5748  2012-03-27 23:50  experiment3\experiment3\experiment3.cpp

     文件       4556  2012-03-27 22:51  experiment3\experiment3\experiment3.dsp

     文件        530  2012-03-27 22:51  experiment3\experiment3\experiment3.dsw

     文件        341  2012-03-27 22:51  experiment3\experiment3\experiment3.h

     文件       1078  2012-03-27 22:51  experiment3\experiment3\experiment3.ico

     文件      53760  2012-03-28 09:14  experiment3\experiment3\experiment3.opt

     文件        929  2012-03-28 09:13  experiment3\experiment3\experiment3.plg

     文件       3109  2012-03-27 22:51  experiment3\experiment3\experiment3.rc

     文件       2115  2012-03-27 22:51  experiment3\experiment3\ReadMe.txt

     文件        801  2012-03-27 22:51  experiment3\experiment3\resource.h

     文件        318  2012-03-27 22:51  experiment3\experiment3\small.ico

     文件        298  2012-03-27 22:51  experiment3\experiment3\StdAfx.cpp

     文件        936  2012-03-27 22:51  experiment3\experiment3\StdAfx.h

     目录          0  2012-03-28 09:13  experiment3\experiment3\Debug

     目录          0  2012-03-28 09:14  experiment3\experiment3

     目录          0  2012-03-28 09:12  experiment3

     文件      50176  2012-03-28 09:14  experiment3\experiment3\experiment3.ncb

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