// Шаблон для последующих программ
#include <windows.h>
#include <tchar.h>
#include <math.h>
#define M_PI 3.14

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
TCHAR WinName[] = _T("MainFrame");

int APIENTRY WinMain(HINSTANCE This, HINSTANCE Prev, LPSTR cmd, int mode)
{
	HWND hWnd;
	MSG msg;
	WNDCLASS wc;
	// Определение класса окна
	wc.hInstance = This;
	wc.lpszClassName = WinName;
	wc.lpfnWndProc = WndProc;
	wc.style = CS_HREDRAW | CS_VREDRAW;
	wc.hIcon = LoadIcon(NULL,IDI_APPLICATION);
	wc.hCursor = LoadCursor(NULL,IDC_ARROW);
	wc.lpszMenuName = NULL;
	wc.cbClsExtra = 0;
	wc.cbWndExtra = 0;
	// Заполнение окна белым цветом
	wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
	if(!RegisterClass(&wc)) return 0;
	// создание окна
	hWnd = CreateWindow(WinName, _T("porabola"), WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,HWND_DESKTOP,NULL,This,NULL);
	ShowWindow(hWnd,mode);
	// цикл обработки сообщений
	while(GetMessage(&msg, NULL, 0, 0))
	{
		TranslateMessage(&msg);
		DispatchMessage(&msg);

	}return 0;
}

// ----------------------------------------------------------- //



LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
	PAINTSTRUCT ps;
	HDC hdc;
	static int sx,sy;
	static HPEN hpen,hpen1,hpen2;
	int a, b, n, x_scr, y_scr,z_scr;
	double x,y,z,x_min,x_max,y_min,y_max,Kx,Ky;




	switch (message)
	{
	case WM_CREATE:
		hpen = CreatePen(PS_SOLID,2,RGB(0, 0, 255));
		break;
	case WM_SIZE:
		sx = LOWORD(lParam);
		sy = HIWORD(lParam);
		break;

	case WM_PAINT:
		x_min = -100;
		x_max =  100;
		y_min = -100;
		y_max =  100;

		Kx = (sx-220)/(x_max - x_min);
		Ky = (sy-220)/(y_max - y_min);

		a = sx/2;
		b = sy/2;

		hdc = BeginPaint(hWnd, &ps);
		SelectObject(hdc,hpen);
		MoveToEx(hdc,0,b,NULL);
		LineTo(hdc,sx,b);
		MoveToEx(hdc, a, 0, NULL);
		LineTo(hdc,a,sy);
		MoveToEx(hdc,20,sy-20,NULL);
		LineTo(hdc,sx-20,20);
		n = y_max-y_min;
		for(y = y_min;y<y_max;y+=5)
		{
			hpen1 = CreatePen(PS_SOLID,2,RGB(255,255./n*(y+y_min),255./n*(y+y_min)));
			SelectObject(hdc,hpen1);
			z = b-100*sin(M_PI/50*sqrt(x_min*x_min+y*y));
			MoveToEx(hdc,x_min*Kx+a+y,z+y,NULL);
			for(x = x_min;x<x_max;x+=5)
			{
				z = b-100*sin(M_PI/50*sqrt(x*x+y*y));
				LineTo(hdc,x*Kx+a+y,z+y);
			}
		}
		EndPaint(hWnd, &ps);
		break;
	case WM_DESTROY:
		DeleteObject(hpen1);


		PostQuitMessage(0);
		break;

	default: return DefWindowProc (hWnd, message, wParam, lParam);
		//break;
	}
	return 0;
}