Win32API编程: 绘图练习--模拟时钟

#include <Windows.h>
#include <math.h>
#include <tchar.h>

BOOLEAN InitWindowClass(HINSTANCE hInstance, int nCmdShow);
LRESULT	CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow){
	MSG msg;

	if(!InitWindowClass(hInstance, nCmdShow)){
		MessageBox(NULL, L"Failed to Create Windows", L"InFo", NULL);
		return 1;
	}

	while(GetMessage(&msg, NULL, 0, 0)){
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}

	return (int)msg.wParam;
}

BOOLEAN InitWindowClass(HINSTANCE hInstance, int nCmdShow){
	WNDCLASSEX wcex;
	HWND hWnd;
	TCHAR szWindowsClass[] = L"窗口示例";
	TCHAR szTitle[] = L"模拟时钟";

	wcex.cbClsExtra = 0;
	wcex.cbSize = sizeof(WNDCLASSEX);
	wcex.cbWndExtra = 0;
	wcex.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
	wcex.hInstance = hInstance;
	wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
	wcex.hIcon = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_APPLICATION));
	wcex.hIconSm = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_APPLICATION));
	wcex.lpfnWndProc = WndProc;
	wcex.lpszClassName = szWindowsClass;
	wcex.lpszMenuName = NULL;
	wcex.style = 0;

	if(!RegisterClassEx(&wcex)){
		return FALSE;
	}

	hWnd = CreateWindow(szWindowsClass, szTitle, WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL);
	if(!hWnd){
		return FALSE;
	}

	ShowWindow(hWnd, nCmdShow);
	UpdateWindow(hWnd);

	return TRUE;
}

LRESULT	CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam){
	HDC hDC;
	PAINTSTRUCT ps;
	HBRUSH hBrush;
	HPEN hPen;
	RECT clientRect;
	SYSTEMTIME x;
	float sita = 0;
	int xOrg, yOrg, rSec, rMin, rHour, rClock, ptLong, xBegin, xEnd, yBegin, yEnd;


	switch(message){
	case WM_CREATE:
		SetTimer(hWnd, 9999, 1000, NULL);				// 发送消息
		break;
	case WM_PAINT:
		hDC = BeginPaint(hWnd, &ps);
		GetClientRect(hWnd, &clientRect);				// 获取窗口大小
			
		hPen = (HPEN)GetStockObject(BLACK_PEN);
		hBrush = CreateSolidBrush(RGB(255, 220, 220));
		SelectObject(hDC, hPen);
		SelectObject(hDC, hBrush);	
		
		xOrg = (clientRect.left + clientRect.right) / 2;					// 时钟表盘圆点坐标
		yOrg = (clientRect.bottom + clientRect.top) / 2;
		
		rClock = min(xOrg, yOrg) * 4 / 5;									// 表盘,秒针,分针,时针半径
		rSec = rClock * 6 / 7;
		rMin = rClock * 5 / 6;
		rHour = rClock * 2 / 3;

		Ellipse(hDC, xOrg - rClock, yOrg - rClock, xOrg + rClock, yOrg + rClock);			// 画圆盘
		for(int i = 0; i < 60; i ++){														// 画刻度
			if(i % 5){
				hPen = CreatePen(PS_SOLID, 2, RGB(255, 0, 0));
				ptLong = rClock * 9 / 10;
			}
			else{
				hPen = CreatePen(PS_SOLID, 5, RGB(255, 0, 0));
				ptLong = rClock * 7 / 8;
			}
			SelectObject(hDC, hPen); 
			
			xBegin = xOrg + rClock * sin(2 * 3.1415926 * i / 60);			// 刻度起止点
			yBegin = yOrg + rClock * cos(2 * 3.1415926 * i / 60);
			xEnd = xOrg + ptLong * sin(2 * 3.1415926 * i / 60);
			yEnd = yOrg + ptLong * cos(2 * 3.1415926 * i / 60);
			
			MoveToEx(hDC, xBegin, yBegin, NULL);
			LineTo(hDC, xEnd, yEnd);
			DeleteObject(hPen);
		}
		
		GetLocalTime(&x);

		hPen = CreatePen(PS_SOLID, 2, RGB(255, 0, 0));									// 秒针
		SelectObject(hDC, hPen);
		
		sita = 2 * 3.1415926 * x.wSecond / 60;
		xBegin = xOrg + (int)(rSec * sin(sita));							// 起止点
		yBegin = yOrg - (int)(rSec * cos(sita));
		xEnd = xOrg + (int)(rClock * sin(sita + 3.1415926) / 8);
		yEnd = yOrg - (int)(rClock * cos(sita + 3.1415926) / 8);

		MoveToEx(hDC, xBegin, yBegin, NULL);
		LineTo(hDC, xEnd, yEnd);

		hPen = CreatePen(PS_SOLID, 5, RGB(0, 0, 0));									// 分针
		SelectObject(hDC, hPen);
		
		sita = 2 * 3.1415926 * x.wMinute / 60;
		xBegin = xOrg + (int)(rMin * sin(sita));
		yBegin = yOrg - (int)(rMin * cos(sita));
		xEnd = xOrg + (int)(rClock * sin(sita + 3.1415926) / 8);
		yEnd = yOrg - (int)(rClock * cos(sita + 3.1415926) / 8);

		MoveToEx(hDC, xBegin, yBegin, NULL);
		LineTo(hDC, xEnd, yEnd);

		hPen = CreatePen(PS_SOLID, 10, RGB(0, 0, 0));									// 时针
		SelectObject(hDC, hPen);
		
		sita = 2 * 3.1415926 * x.wHour / 12;
		xBegin = xOrg + (int)(rHour * sin(sita));
		yBegin = yOrg - (int)(rHour * cos(sita));
		xEnd = xOrg + (int)(rClock * sin(sita + 3.1415926) / 8);
		yEnd = yOrg - (int)(rClock * cos(sita + 3.1415926) / 8);

		MoveToEx(hDC, xBegin, yBegin, NULL);
		LineTo(hDC, xEnd, yEnd);

		DeleteObject(hPen);
		DeleteObject(hBrush);
		EndPaint(hWnd, &ps);
		break;
	case WM_TIMER:
		if(wParam == 9999){
			InvalidateRect(hWnd, NULL, true);
		}
		break;
	case WM_SIZE:
		InvalidateRect(hWnd, NULL, TRUE);
		break;
	case WM_DESTROY:
		PostQuitMessage(0);
		break;
	default:
		return DefWindowProc(hWnd, message, wParam, lParam);
	}

	return 0;
}