画正弦线

代码：

case WM_PAINT:hdc = BeginPaint(hWnd, &ps);// TODO: 在此添加任意绘图代码...//画正玄线#define  PI 3.1415926#defineSEGMENT 500int cxClient,cyClient;RECT rect;::GetClientRect(hWnd, &rect);cxClient = rect.right - rect.left;cyClient = rect.bottom - rect.top;POINTpt[SEGMENT];for (int i=0;i<SEGMENT;i++){pt[i].x = i * cxClient/SEGMENT;  //cxClient的长度被分成SEGMENT份pt[i].y =  (int)((cyClient/2)*(1 - sin(2 * PI * i/SEGMENT))); //因为sin(2pi)取反，因为数学坐标Y轴向上，而系统中坐标Y轴向下，+cyClient/2是将坐标原点移到左上角}::Polyline(hdc, pt, SEGMENT); //绘图函数EndPaint(hWnd, &ps);break;