/*
	Netwar
	Copyright (C) 2002  Daniel Grund, Kyle Kakligian, Jason Komutrattananon, & Brian Hibler.

	This file is part of Netwar.

	Netwar is free software; you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation; either version 2 of the License, or
	(at your option) any later version.

	Netwar is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with Netwar; if not, write to the Free Software
	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package netwar.utils.vectorgraphics;
import netwar.utils.*;
import java.awt.Color;
import netwar.game.GameViewer;

/** Primitive GraphicThing.
 * This represents a parallelogram to be drawn filling the space between
 * four points in a particular color.
 * No warranty is made for the correctness of the results if the class is 
 * improperly used: The points should be provided to the constructor in 
 * adjacent order (i.e. two consecutive arguments are consecutive vertices).
 * It is the responsibility of the creating class and any other classes that 
 * call this to keep the points in a Parallelogram shape.
 */
public class GraphicParallelogram extends GraphicThing {
	private SelfConvertingPoint a;
	private SelfConvertingPoint b;
	private SelfConvertingPoint c;
	private SelfConvertingPoint d;
	private Color col;
	/** Create a GraphicParallelogram without external point control.
	 * The object can only be moved by calling translate and rotate.
	 * @param A One initial endpoint.
	 * @param B Another initial endpoint.
	 * @param C Another initial endpoint.
	 * @param D Yet another initial endpoint.
	 * @param COL The color of the line segment.
	 */
	public GraphicParallelogram(Point3D A, Point3D B, Point3D C, Point3D D, Color COL) {
		a = new SelfConvertingPoint(A);
		b = new SelfConvertingPoint(B);
		c = new SelfConvertingPoint(C);
		d = new SelfConvertingPoint(D);
		col = COL;
	}
	/** Create a GraphicParallelogram with external point control.
	 * The object can be manipulated by changing A, B, C and D outside the class.
	 * @param A One endpoint.
	 * @param B Another endpoint.
	 * @param C Another endpoint.
	 * @param D Yet another endpoint.
	 * @param COL The color of the line segment.
	 */
	public GraphicParallelogram(SelfConvertingPoint A, SelfConvertingPoint B, SelfConvertingPoint C, SelfConvertingPoint D, Color COL) {
		a = A;
		b = B;
		c = C;
		d = D;
		col = COL;
	}
	public float getZ(Transform t) {
		Point3D pt = new Point3D(a);
		float Z;
		Z = a.getScreenPoint(t).z;
		Z += b.getScreenPoint(t).z;
		Z += c.getScreenPoint(t).z;
		Z += d.getScreenPoint(t).z;
		Z /= 4;
		return Z;
	}
	public void draw(GameViewer v) {
		if(!isOnScreen(v.getTransform()))
			return;
		v.setColor(col);
		v.drawTriangle(a,b,c);
		v.drawTriangle(a,d,c);
	}
	public GraphicThing rotate(Point3D axisPt, Point3D axisDir, int angle)
	{
		a.doRotate(axisPt, axisDir, angle);
		b.doRotate(axisPt, axisDir, angle);
		c.doRotate(axisPt, axisDir, angle);
		d.doRotate(axisPt, axisDir, angle);
		update();
		return this;
	}
	public GraphicThing translate(Point3D offset)
	{
		a.doSum(offset);
		b.doSum(offset);
		c.doSum(offset);
		d.doSum(offset);
		update();
		return this;
	}
	public boolean isOnScreen(Transform t) {
		return (a.isOnScreen(t) || b.isOnScreen(t) || c.isOnScreen(t) || d.isOnScreen(t));
	}
	public void explode(Point3D epicenter) {
		//This is a case where the parallelogram shape is needed for correctness of function.
		kill();
		unlink();
		Point3D center = getCenter();
		Point3D velocity = center.getDifference(epicenter);
		netwar.game.Projectile.newProjectile(new netwar.game.projectile.DebrisFragment(this), center, velocity, 0, 0, 100, null, null);
	}
	Point3D getCenter() {
		return a.getSum(c).doProduct(0.5f);
	}
	void unlink() {
		a = new SelfConvertingPoint(a);
		b = new SelfConvertingPoint(b);
		c = new SelfConvertingPoint(c);
		d = new SelfConvertingPoint(d);
	}
	public GraphicThing copy() {
		GraphicParallelogram gp = new GraphicParallelogram(a,b,c,d,col);
		gp.unlink();
		return gp;
	}
}