using System;

using System.Drawing;

using System.Drawing.Imaging;

using System.Collections.Generic;

namespace Assistance {

	public class ModifierSnowflake: Modifier {

		public static readonly int rays = 6;

		public ActivePoint center;

		public ModifierSnowflake(Document document, Point center): base(document) {

			this.center = new ActivePoint(this, ActivePoint.Type.CircleCross, center);

		}

		public override void draw(System.Drawing.Graphics g) {

			for(int i = 0; i < rays/2; ++i) {

				Point pp0 = center.position;

				Point pp1 = center.position + new Point(100.0, 0.0).rotate( i*2.0*Math.PI/(double)rays );

				Geometry.truncateInfiniteLine(new Rectangle(g.VisibleClipBounds), ref pp0, ref pp1);

				g.DrawLine(pen, pp0.toFloat(), pp1.toFloat());

			}

		}

		public override void getTransformFuncs(List<geometry.transformfunc> transformFuncs) {</geometry.transformfunc>

			Point p0 = center.position;

			for(int i = 0; i < rays; ++i) {

				double angle = i*2.0*Math.PI/(double)rays;

				double s = Math.Sin(angle);

				double c = Math.Cos(angle);

				transformFuncs.Add(delegate(Point p) {

					double x = p.x - p0.x;

					double y = p.y - p0.y;

					return p0 + new Point(c*x - s*y, s*x + c*y);

				});

				transformFuncs.Add(delegate(Point p) {

					double x = p.x - p0.x;

					double y = p.y - p0.y;

					return p0 + new Point(c*x + s*y, s*x - c*y);

				});

			}

		}

	}

}