MoveRoundTo.java

package loon.action;

import loon.geom.Vector2f;
import loon.utils.Easing.EasingMode;
import loon.utils.MathUtils;
import loon.utils.timer.EaseTimer;

/**
 * 让指定对象做环绕运动(与CircleTo差异在于CircleTo不会自行停止,且CircleTo仅以对象本身为中心做360度旋转),需要偏移或矫正显示位置时请设置setOffset参数
 */
public class MoveRoundTo extends ActionEvent {

	private final float angle;
	private final float startAngle;
	private final float radius;
	private final float startRadius;
	private Vector2f startPoint,oldStartPoint;
	private Vector2f centerPoint,oldCenterPoint;
	private EaseTimer timer;
	
	public MoveRoundTo(float angle, float radius, Vector2f centerPoint,
			float duration, EasingMode easing) {
		this(0f, angle, 0f, radius, centerPoint, null, duration, 1f / 60f, easing);
	}

	public MoveRoundTo(float angle, float radius, Vector2f centerPoint,
			EasingMode easing) {
		this(0f, angle, 0f, radius, centerPoint, null, 1f, 1f / 60f, easing);
	}

	public MoveRoundTo(float angle, float radius, Vector2f centerPoint,
			float duration, float delay, EasingMode easing) {
		this(0f, angle, 0f, radius, centerPoint, null, duration, delay, easing);
	}

	public MoveRoundTo(float startAngle, float angle, float startRadius,
			float radius, Vector2f centerPoint) {
		this(startAngle, angle, startRadius, radius, centerPoint, null, 1f,
				1f / 60f, EasingMode.Linear);
	}

	public MoveRoundTo(float startAngle, float angle, float startRadius,
			float radius, float duration, Vector2f centerPoint) {
		this(startAngle, angle, startRadius, radius, centerPoint, null, duration,
				1f / 60f, EasingMode.Linear);
	}

	public MoveRoundTo(float startAngle, float angle, float startRadius,
			float radius, Vector2f centerPoint, Vector2f startPoint,
			float duration, float delay, EasingMode easing) {
		if (angle > 360) {
			angle = 360;
		}
		this.angle = angle;
		this.radius = radius;
		this.startAngle = startAngle;
		this.startRadius = startRadius;
		this.centerPoint = centerPoint;
		this.startPoint = startPoint;
		if (startPoint == null) {
			startPoint = new Vector2f();
		}
		this.timer = new EaseTimer(duration, delay, easing);
		this.oldStartPoint = startPoint;
		this.oldCenterPoint = centerPoint;
	}

	@Override
	public void update(long elapsedTime) {
		timer.update(elapsedTime);
		if (timer.isCompleted()) {
			_isCompleted = true;
			float radian = MathUtils.toRadians(this.startAngle + this.angle);
			float x = this.centerPoint.x + MathUtils.cos(radian)
					* (this.startRadius + this.radius);
			float y = this.centerPoint.y + MathUtils.sin(radian)
					* (this.startRadius + this.radius);
			this.original.setLocation(x +original.getWidth()/2+ offsetX, y +original.getHeight()/2+ offsetY);
			return;
		}
		float currentRadius = this.startRadius + this.radius
				* timer.getProgress();
		float currentAngle = this.startAngle + this.angle * timer.getProgress();
		float radian = MathUtils.toRadians(currentAngle);
		this.startPoint.x = (this.centerPoint.x + MathUtils.cos(radian)
				* currentRadius);
		this.startPoint.y = (this.centerPoint.y + MathUtils.sin(radian)
				* currentRadius);
		this.original.setLocation(this.startPoint.x + offsetX, this.startPoint.y
				+ offsetY);
	}

	@Override
	public void onLoad() {
		if (startPoint == null || startPoint.getX() == -1 || startPoint.getY() == -1) {
			this.startPoint = new Vector2f(original.getX(), original.getY());
		}
		this.oldStartPoint.set(startPoint);
		this.oldCenterPoint.set(centerPoint);
	}

	@Override
	public boolean isComplete() {
		return _isCompleted;
	}

	@Override
	public ActionEvent cpy() {
		MoveRoundTo mover = new MoveRoundTo(startAngle, angle, startRadius, radius,
				oldCenterPoint, oldStartPoint, timer.getDuration(), timer.getDelay(),
				timer.getEasingMode());
		mover.set(this);
		return mover;
	}

	@Override
	public ActionEvent reverse() {
		return cpy();
	}

	@Override
	public String getName() {
		return "moveround";
	}
}