/**
* Copyright 2001 Jean-Francois Doue
*
* This file is part of Asteroid Zone. Asteroid Zone 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.
* Asteroid Zone 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 Asteroid Zone; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307 USA
*/
package asteroids;
import javax.microedition.lcdui.*;
/**
* Class to implement a rocket shot by the player's spaceship.
* @author Jean-Francois Doue
* @version 1.4, 2002/10/14
*/
public class Rocket extends Mobile {
/**
* The orientation of the rocket.
*/
public byte angle;
/**
* The rockets currently existing in the game
*/
public static Pool rockets;
private int _rangex, _rangey; // The distance travelled by the rocket.
static {
// Create and populate the rocket pool.
Rocket[] array = new Rocket[10];
for (int i = array.length - 1; i >= 0; i--) {
array[i] = new Rocket();
}
rockets = new Pool(array);
}
public Rocket() {
}
/**
* Initializes a Rocket instance by setting its position
* and angle.
*/
public final void init(int x, int y, byte angle, int vx, int vy) {
moveTo(x, y);
setVelocity((cos[angle] << 4) + vx, (sin[angle] << 4) + vy);
this.angle = angle;
_rangex = 0;
_rangey = 0;
}
/**
* Move the rockets and remove those which have expired.
*/
public static final void move() {
for (rockets.current = rockets.count - 1; rockets.current >= 0;) {
Rocket r = (Rocket)rockets.pool[rockets.current--];
int rangex = r._rangex >> 8;
int rangey = r._rangey >> 8;
int maxRange = (((width <= height) ? width : height) * 8) / 10;
// Determines if the rocket has travelled its maximum distance
// (80% of the screens smallest dimension).
if ((rangex * rangex + rangey * rangey) > maxRange * maxRange) {
rockets.removeCurrent();
} else {
r.xold = r.x;
r.yold = r.y;
r._x += r.vx;
r._y += r.vy;
r.x = r._x >> 8;
r.y = r._y >> 8;
// If a border has been hit, wrap the trajectory around
// the screen. The new origin is the projection of the
// intersection point on the opposite border.
if (r.x <= 0) {
r.moveTo(width - 2, r.y);
} else if (r.x >= width - 1) {
r.moveTo(1, r.y);
} else if (r.y <= 0) {
r.moveTo(r.x, height - 2);
} else if (r.y >= height - 1) {
r.moveTo(r.x, 1);
}
// Upgrade the range travelled.
r._rangex += r.vx;
r._rangey += r.vy;
}
}
}
/**
* Draws all the rockets of the supplied object pool using the
* specified graphic context.
*/
public static final void draw(Graphics g) {
for (int i = 0; i < rockets.count; i++) {
Rocket r = (Rocket)rockets.pool[i];
g.drawLine(r.x, r.y, r.x, r.y);
}
}
}