gdisample4_6.cpp

可视化编程关于windows窗口的建立中的一个例子

// GDISample4_6.cpp : Defines the entry point for the application.
//

#include "stdafx.h"
#include "resource.h"

#define MAX_LOADSTRING 100
#define Pi 3.1415926

double dfTheta=0,dfRange=100.0;		//正弦曲线的角度变量
long i=0,j=0;
long lCentreX=0,lCentreY=0,lRadious=(long)(0.2*dfRange);
//定义圆心坐标和圆半径
POINT lpSin[100];	//定义正弦曲线的点坐标

// 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 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_GDISAMPLE4_6, szWindowClass, MAX_LOADSTRING);
	MyRegisterClass(hInstance);
	
	// Perform application initialization:
	if (!InitInstance (hInstance, nCmdShow)) 
	{
		return FALSE;
	}
	
	hAccelTable = LoadAccelerators(hInstance, (LPCTSTR)IDC_GDISAMPLE4_6);
	
    for(int j=0;j<100;j++)		//生成正弦曲线的点坐标
    {
		lpSin[j].x=(long)(j*2*Pi/100*60);
		lpSin[j].y=(long)(dfRange*sin(j*2*Pi/100));
    }
	
	// 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_GDISAMPLE4_6);
	wcex.hCursor		= LoadCursor(NULL, IDC_ARROW);
	wcex.hbrBackground	= (HBRUSH)(COLOR_WINDOW+1);
	wcex.lpszMenuName	= (LPCSTR)IDC_GDISAMPLE4_6;
	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 our global variable
	
	hWnd = CreateWindow(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
		CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL);
	
	if (!hWnd)
	{
		return FALSE;
	}
	
	ShowWindow(hWnd, nCmdShow);
	UpdateWindow(hWnd);
	
	return TRUE;
}

//
//  FUNCTION: WndProc(HWND, unsigned, WORD, LONG)
//
//  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)
{
	
	HDC hDC;				//定义设备环境句柄
	HBRUSH hBrush;			//定义画刷句柄
	HPEN hPen;				//定义画笔句柄
	PAINTSTRUCT PtStr;//定义包含绘图信息的结构体变量
	int wmId, wmEvent;
	TCHAR szHello[MAX_LOADSTRING];
	LoadString(hInst, IDS_HELLO, szHello, MAX_LOADSTRING);
	
	switch (message) 
	{
	case WM_COMMAND:
		wmId    = LOWORD(wParam); 
		wmEvent = HIWORD(wParam); 
		// Parse the menu selections:
		switch (wmId)
		{
		case IDM_ABOUT:
			DialogBox(hInst, (LPCTSTR)IDD_ABOUTBOX, hWnd, (DLGPROC)About);
			break;
		case IDM_EXIT:
			DestroyWindow(hWnd);
			break;
		default:
			return DefWindowProc(hWnd, message, wParam, lParam);
		}
		break;
		case WM_PAINT:
			hDC=BeginPaint(hWnd,&PtStr);		//获得设备环境指针
			SetWindowOrgEx(hDC,-200,-200,NULL);//设置原点坐标
			hPen=CreatePen(PS_DASH,1,RGB(255,0,0));	//建新画笔
			SelectObject(hDC,hPen);				//选入画笔
			Polyline(hDC,lpSin,100);			//绘制正弦曲线
			
			if(i<=25) //第一个1/4周期
			{	hPen=CreatePen(PS_DASH,1,RGB(255,0,0));	
			hBrush=CreateHatchBrush(HS_BDIAGONAL,RGB(255,0,0));
			lRadious=(long)(dfRange*0.2+i%25*dfRange*0.4/25);  //计算半径
			}
			else if(i<=50)//第二个1/4周期
			{	hPen=CreatePen(PS_DASH,1,RGB(0,255,0));
			hBrush=CreateHatchBrush(HS_DIAGCROSS,RGB(0,255,0));
			lRadious=(long)(dfRange*0.2+i%25*dfRange*0.4/25);
			}
			else if(i<=75)//第三个周期
			{	hPen=CreatePen(PS_DASH,1,RGB(0,0,255));
			hBrush=CreateHatchBrush(HS_CROSS,RGB(0,0,255));
			lRadious=(long)(dfRange*0.2+i%25*dfRange*0.4/25);
			}
			else//第四个周期
			{	hPen=CreatePen(PS_DASH,1,RGB(255,255,0));
			hBrush=CreateHatchBrush(HS_VERTICAL,RGB(255,255,0));
			lRadious=(long)(dfRange*0.2+i%25*dfRange*0.4/25);
			}
			SelectObject(hDC,hBrush);	//选入画刷
			SelectObject(hDC,hPen);	//选入画笔
			lCentreX=lpSin[i].x;		//圆心x坐标
			lCentreY=lpSin[i].y;		//圆心y坐标
			Ellipse(hDC,lCentreX-lRadious,lCentreY-lRadious,
    	           lCentreX+lRadious,lCentreY+lRadious);   //画圆
			
			i++;
			DeleteObject(hPen);		//删除画笔
			DeleteObject(hBrush);	//删除画刷
			EndPaint(hWnd,&PtStr);	//删除设备环境指针
			Sleep(100);			//停0.1秒
			if(i<100) InvalidateRect(hWnd,NULL,1);	//刷新用户区
			break;
		case WM_DESTROY:
			PostQuitMessage(0);
			break;
		default:
			return DefWindowProc(hWnd, message, wParam, lParam);
	}
	return 0;
}

// Mesage handler for about box.
LRESULT CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
{
	switch (message)
	{
	case WM_INITDIALOG:
		return TRUE;
		
	case WM_COMMAND:
		if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL) 
		{
			EndDialog(hDlg, LOWORD(wParam));
			return TRUE;
		}
		break;
	}
    return FALSE;
}