Trail.java

package com.tutorial.main;

import java.awt.*;

/**
 * Created by narhwal on 6/12/2016.
 */
public class Trail extends GameObject {


    private float alpha = 1;
    private Handler handler;
    private Color color;
    private int width, height;
    private float life;

    public Trail(int x, int y, ID id, Color color, int width, int height, float life, Handler handler) {
        super(x, y, id);
        this.handler = handler;
        this.color = color;
        this.width = width;
        this.height = height;
        this.life = life;
    }

    @Override
    public Rectangle getBounds() {
        return null;
    }

    @Override
    public void tick() {
        if (alpha > life) {
            alpha -= life - 0.001f;
        } else handler.removeObject(this);
    }

    @Override
    public void render(Graphics g) {
        Graphics2D g2d = (Graphics2D) g;
        g2d.setComposite(makeTransparent(alpha));
        g.setColor(color);
        //g.fillRect(x, y, height, width);
        double test = alpha * 15;
        int size = (int) test;
        g.fillOval(x, y, size, size);
        g2d.setComposite(makeTransparent(1));
    }

    private AlphaComposite makeTransparent(float alpha) {
        int type = AlphaComposite.SRC_OVER;
        return (AlphaComposite.getInstance(type, alpha));
    }
}