КГГ1

using System;
using System.Drawing;
using System.Linq;
using OpenTK.Graphics.OpenGL;
using System.Windows.Forms;

namespace КГГ_1
{
    public partial class MainForm : Form
    {
        private double MinY, MaxY;
        public MainForm()
        {
            InitializeComponent();
        }

        private double A= 2 , B = 5;
        private int WR, HR;
        private double F(double x)
        {
            return 20-x*Math.Sin(x*x);
        }

        private void MainForm_Load(object sender, EventArgs e)
        {

        }

        private void glc_Resize(object sender, EventArgs e)
        {
            GL.ClearColor(Color.White);
            WR = glc.Width;
            HR = glc.Height;
            GL.MatrixMode(MatrixMode.Projection);
            GL.LoadIdentity();
            GL.Ortho(0, WR, 0, HR, -1, 1); // Bottom-left corner pixel has coordinate (0, 0)
            GL.Viewport(0, 0, WR, HR); // Use all of the glControl painting area
            glc.Invalidate();
        }

        private void glc_Paint(object sender, PaintEventArgs e)
        {
            var values = new double[WR];
            for (var i = 0; i < WR; ++i)
            {
                values[i] = F(i*(B - A)/WR + A);
            }
            MinY = values.Min();
            MaxY = values.Max();

            GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
            GL.LineWidth(1);
            GL.Color3(Color.Red);
            GL.Begin(BeginMode.LineStrip);
            for (var i = 0; i < WR; ++i)
            {
                DrawPoint(i, values[i]);
            }
            GL.End();

            GL.LineWidth(1);
            GL.Color3(Color.Black);
            GL.Begin(BeginMode.Lines);
            if (MinY <= 0 && 0 <= MaxY)
            {
                DrawPoint(0, 0);
                DrawPoint(WR, 0);
            }
            if (A <= 0 && 0 <= B)
            {
                GL.Vertex2((-A)*WR/(B - A), 0);
                GL.Vertex2((-A)*WR/(B - A), HR);
            }
            GL.End();
            glc.SwapBuffers();
        }

        private void DrawPoint(int x, double y)
        {
            GL.Vertex2(x, (y-MinY)*HR/(MaxY-MinY));
        }

        private void glc_Load(object sender, EventArgs e)
        {
            GL.ClearColor(Color.White);
            WR = glc.Width;
            HR = glc.Height;
            GL.MatrixMode(MatrixMode.Projection);
            GL.LoadIdentity();
            GL.Ortho(0, WR, 0, HR, -1, 1); // Bottom-left corner pixel has coordinate (0, 0)
            GL.Viewport(0, 0, WR, HR); // Use all of the glControl painting area
            glc.Invalidate();
        }
    }
}