Arc

/*
* @(#)Arcs.java 1.19 01/12/03
*
* Copyright 2002 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/

package java2d.demos.Arcs_Curves;

import java.awt.*;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Arc2D;
import java.awt.geom.AffineTransform;
import java2d.AnimatingSurface;


/**
* Arc2D Open, Chord & Pie arcs; Animated Pie Arc.
*/
public class Arcs extends AnimatingSurface {

private static String types[] = {"Arc2D.OPEN","Arc2D.CHORD","Arc2D.PIE"};
private static final int CLOSE = 0;
private static final int OPEN = 1;
private static final int FORWARD = 0;
private static final int BACKWARD = 1;
private static final int DOWN = 2;
private static final int UP = 3;

private int aw, ah; // animated arc width & height
private int x, y;
private int angleStart = 45;
private int angleExtent = 270;
private int mouth = CLOSE;
private int direction = FORWARD;


public Arcs() {
setBackground(Color.white);
}


public void reset(int w, int h) {
x = 0; y = 0;
aw = w/12; ah = h/12;
}


public void step(int w, int h) {
// Compute direction
if (x+aw >= w-5 && direction == FORWARD)
direction = DOWN;
if (y+ah >= h-5 && direction == DOWN)
direction = BACKWARD;
if (x-aw <= 5 && direction == BACKWARD)
direction = UP;
if (y-ah <= 5 && direction == UP)
direction = FORWARD;

// compute angle start & extent
if (mouth == CLOSE) {
angleStart -= 5;
angleExtent += 10;
}
if (mouth == OPEN) {
angleStart += 5;
angleExtent -= 10;
}
if (direction == FORWARD) {
x += 5; y = 0;
}
if (direction == DOWN) {
x = w; y += 5;
}
if (direction == BACKWARD) {
x -= 5; y = h;
}
if (direction == UP) {
x = 0; y -= 5;
}
if (angleStart == 0)
mouth = OPEN;
if (angleStart > 45)
mouth = CLOSE;
}


public void render(int w, int h, Graphics2D g2) {

g2.setStroke(new BasicStroke(5.0f));
// Draw Arcs
for (int i = 0; i < types.length; i++) {
Arc2D arc = new Arc2D.Float(i);
arc.setFrame((i+1)*w*.2, (i+1)*h*.2, w*.17, h*.17);
arc.setAngleStart(45);
arc.setAngleExtent(270);
g2.setColor(Color.blue);
g2.draw(arc);
g2.setColor(Color.gray);
g2.fill(arc);
g2.setColor(Color.black);
g2.drawString(types[i], (int)((i+1)*w*.2), (int)((i+1)*h*.2-3));
}

// Draw Animated Pie Arc
Arc2D pieArc = new Arc2D.Float(Arc2D.PIE);
pieArc.setFrame(0, 0, aw, ah);
pieArc.setAngleStart(angleStart);
pieArc.setAngleExtent(angleExtent);
AffineTransform at = AffineTransform.getTranslateInstance(x, y);
switch (direction) {
case DOWN : at.rotate(Math.toRadians(90)); break;
case BACKWARD : at.rotate(Math.toRadians(180)); break;
case UP : at.rotate(Math.toRadians(270));
}
g2.setColor(Color.blue);
g2.fill(at.createTransformedShape(pieArc));
}


public static void main(String argv[]) {
createDemoFrame(new Arcs());
}
}