// main.cs

// C:>csc /t:winexe main.cs

using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;

class AWindow : System.Windows.Forms.Form
{

        private int m_mouse_x;
        private int m_mouse_y;


	private void OnPaint(object sender, System.Windows.Forms.PaintEventArgs e)
	{
		System.Drawing.Graphics g = e.Graphics;

		int[] coords0 = new int[] {5,5, 80, 80 };
		//int[] coords0 = new int[] {30,30, 180, 38};
        int iLen = coords0.Length;

        iLen -= 2;
		GraphicsPath path = new GraphicsPath();

		for(int i=0; i<iLen; i+=2)
		{
			path.AddLine(coords0[i+0], coords0[i+1], 
				    coords0[i+2], coords0[i+3]);
		}

		path.AddLine(coords0[iLen-2], coords0[iLen-1], 
				     coords0[0], coords0[1]);

		// Create pen
		Pen redPen = new Pen( Color.Red, 1 );

		// Draw path to screen.
		g.DrawPath( redPen, path );

		// Now tidy up
		redPen.Dispose();

		// ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** //

		for(int i=0; i<iLen; i+=2)
		{
			double p0x = coords0[i+0];
			double p0y = coords0[i+1];

			double p1x = coords0[i+2];
			double p1y = coords0[i+3];

			double dirx = p1x - p0x;
			double diry = p1y - p0y;

			double ang = -3.14/2.0;
			double nx = dirx*Math.Cos( ang ) - diry*Math.Sin( ang );
			double ny = dirx*Math.Sin( ang ) + diry*Math.Cos( ang );

			// Normalize our normals
			double length = Math.Sqrt(Math.Abs(nx*nx + ny*ny));

			nx = nx/length;
			ny = ny/length;

                        // ------------------------Draw Normal----------------------- //
			double p2x = nx*20;
			double p2y = ny*20;

			p2x = p1x + p2x;
			p2y = p1y + p2y;

			//path.AddLine((float)p1x, (float)p1y, 
			//	         (float)p2x, (float)p2y);

			// Create pen
			Pen bluePen = new Pen( Color.Blue, 1 );

			// Draw path to screen.
			g.DrawLine( bluePen, (float)p1x, (float)p1y,   (float)p2x, (float)p2y );

			// Now tidy up
			bluePen.Dispose();
			// -----------------------End Draw Normal-------------------- //


			// Mouse Position
			double mousex = (float)m_mouse_x;
			double mousey = (float)m_mouse_y;

			double d = nx*p1x + ny*p1y;
			double k = nx*mousex + ny*mousey;

                        if( k>d )
                           this.Text = "inside";
                        else
                           this.Text = "outside";

		}


	}// End of OnPaint(..)


	bool isInsidePoly()
	{
		// We'll use the dot product to determine which side of the line where on.
		int[] coords0 = new int[] {5,5, 30, 30 };
		int iLen = coords0.Length;

		iLen -= 2;

		for(int i=0; i<iLen; i+=2)
		{
			float p0x = coords0[i+0];
			float p0y = coords0[i+1];

			float p1x = coords0[i+2];
			float p1y = coords0[i+3];

			// Mouse Position
			float mousex = 0;
			float mousey = 0;

			mousex = mousey;

			float d = p0x*p1x + p0y*p1y;
            //float k = 


		}

		return false;

	}

        private void OnMouseMoveEvent(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            int mouse_x = e.X;
            int mouse_y = e.Y;

            m_mouse_x = mouse_x;
            m_mouse_y = mouse_y;

            Invalidate();
            this.Update();
        }


	AWindow()
	{
		this.Paint += new System.Windows.Forms.PaintEventHandler(this.OnPaint);
                this.MouseMove += new System.Windows.Forms.MouseEventHandler(this.OnMouseMoveEvent);
	}// End of AWindow()

	// Application Entry Point
	static void Main()
	{
		System.Windows.Forms.Application.Run(new AWindow());
	}// End Main()
}// End of AWindow class