BEZIER程序

void DrawBezier(HDC hdc,POINT apt[]){PolyBezier(hdc,apt,4);MoveToEx(hdc,apt[0].x,apt[0].y,NULL);LineTo(hdc,apt[1].x,apt[1].y);MoveToEx(hdc,apt[2].x,apt[2].y,NULL);LineTo(hdc,apt[3].x,apt[3].y);}LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam){static POINT apt[4];int wmId, wmEvent,cxClient,cyClient;PAINTSTRUCT ps;HDC hdc;switch (message) {case WM_SIZE:cxClient=LOWORD(lParam);cyClient=HIWORD(lParam);apt[0].x=cxClient/4;apt[0].y=cyClient/2;apt[1].x=cxClient/2;apt[1].y=cxClient/4;apt[2].x=cxClient/2;apt[2].y=3*cyClient/4;apt[3].x=3*cxClient/4;apt[3].y=cyClient/2;break;case WM_LBUTTONDOWN:break;case WM_RBUTTONDOWN:break;case WM_MOUSEMOVE:if(wParam&MK_LBUTTON||wParam&MK_RBUTTON){hdc=GetDC(hWnd);SelectObject(hdc,GetStockObject(WHITE_PEN));DrawBezier(hdc,apt);if(wParam&MK_LBUTTON){apt[1].x=LOWORD(lParam);apt[1].y=HIWORD(lParam);}if(wParam&MK_RBUTTON){apt[2].x=LOWORD(lParam);apt[2].y=HIWORD(lParam);}SelectObject(hdc,GetStockObject(BLACK_PEN));DrawBezier(hdc,apt);ReleaseDC(hWnd,hdc);}break;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, &ps);// TODO: Add any drawing code here...DrawBezier(hdc,apt);EndPaint(hWnd,&ps);break;case WM_DESTROY:PostQuitMessage(0);break;default:return DefWindowProc(hWnd, message, wParam, lParam); } return 0;}