// Листинг 1.8. Синусоида

#define _USE_MATH_DEFINES
#include <cmath>
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
   PAINTSTRUCT ps;
   HDC hdc;
   static int sx, sy;
   static HPEN hpen1, hpen2;
   int a, b, x_scr, y_scг; //Экранные координаты
   double x, h; //Физические координаты
   switch(message)
   {
   case WM_CREATE :
      hpen1 = CreatePen(PS_SOLID, 2, RGB(0, 0, 255));
      hpen2 = CreatePen(PS_SOLID, 2, RGB(255, 0, 0));
      break;
   case WM_SIZE:
      sx = LOWORD(lParam); //Ширина окна
      sy = HIWORD(lParam); //Высота окна
      break;
   case WM_PAINT:
      hdc = BeginPaint(hWnd, &ps);
      a = sx/2; // Координаты
      b = sy/2; // центра окна

      SelectObject(hdc, hpen1);	//Синее перо
      MoveToEx(hdc, 0, b, NULL);
      LineTo(hdc, sx, b);
      MoveToEx(hdc, a, 0, NULL);
      LineTo(hdc, a, sy);
      MoveToEx(hdc, 0, b, NULL);
      SelectObject(hdc,hpen2);	//Красное перо
      h = 3*M_PI/a;				//Шаг по оси x
      for (x = -M_PI, x_scr = 0; x < M_PI; x += h)
      {
         x_scr = (x + M_PI)*a/M_PI;
         y_scг = b - b*sin(x);
         LineTo (hdc, x_scr, y_scг) ;
      }
      EndPaint(hWnd, &ps);
      break;
   case WM_DESTROY:
      DeleteObject(hpen1) ;
      DeleteObject(hpen2) ;
      PostQuitMessage(0) ;
      break;
   default: return DefWindowProc(hWnd, message, wParam, lParam);
   }
   return 0;
}