usingSystem;
usingSystem.Collections.Generic;
usingSystem.ComponentModel;
usingSystem.Data;
usingSystem.Drawing;
usingSystem.Linq;
usingSystem.Text;
usingSystem.Threading.Tasks;
usingSystem.Windows.Forms;

namespace OKGL5
{
publicpartialclassFormSnow : Form
    {
publicFormSnow()
        {
InitializeComponent();
        }

Void Snow(PointF A, PointF B, PointF C, int n, Graphics g, PenPen, PenRubber)
        {
if (n > 0)
            {
                --n;
PointF a = newPointF(A.X + (B.X - A.X) / 3, A.Y + (B.Y - A.Y) / 3);
PointF b = newPointF(A.X + 2 * (B.X - A.X) / 3, A.Y + 2 * (B.Y - A.Y) / 3);
PointF c = newPointF((B.X + A.X) / 2, (B.Y + A.Y) / 2);

PointFan = newPointF(A.X + (C.X - A.X) / 3, A.Y + (C.Y - A.Y) / 3);
PointFbn = newPointF(C.X + 2 * (B.X - C.X) / 3, C.Y + 2 * (B.Y - C.Y) / 3);
PointFcn = newPointF(c.X - (C.X - c.X) / 3, c.Y + (c.Y - C.Y) / 3);

g.DrawLine(Pen, a, cn);
g.DrawLine(Pen, b, cn);
g.DrawLine(Rubber, a, b);

Snow(a, cn, b, n, g, Pen, Rubber);
Snow(cn, b, a, n, g, Pen, Rubber);
Snow(A, a, an, n, g, Pen, Rubber);
Snow(B, b, bn, n, g, Pen, Rubber);
            }
        }

privatevoidbtnDraw_Click(objectsender, EventArgs e)
        {
Graphics g = CreateGraphics();
PenPen = newPen(Color.Blue, 2);
PenRubber = newPen(Color.Yellow, 2);

PointF A = newPointF(450, 400);
PointF B = newPointF(50, 400);
PointF C = newPointF(250, 50);

g.DrawLine(Pen, A, B);
g.DrawLine(Pen, B, C);
g.DrawLine(Pen, C, A);
try
            {
int n = Convert.ToInt32(txbGlub.Text);
Snow(A, B, C, n, g, Pen, Rubber);
Snow(B, C, A, n, g, Pen, Rubber);
Snow(C, A, B, n, g, Pen, Rubber);
            }
catch (Exception)
            {
int n = 1;
            }
        }

Privatevoid btnClear_Click(objectsender, EventArgs e)
        {
Graphics g = CreateGraphics();
g.Clear(Color.Yellow);
txbGlub.Text = "";
        }

privatevoidbtnClose_Click(objectsender, EventArgs e)
        {
Application.Exit();
        }
    }
}