Bullet.js

// ======
// BULLET
// ======

"use strict";

/* jshint browser: true, devel: true, globalstrict: true */

/*
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*/


// A generic contructor which accepts an arbitrary descriptor object
function Bullet(descr) {

	// Common inherited setup logic from Entity
	this.setup(descr);

	// Make a noise when I am created (i.e. fired) if this.playSound is true so we dont get an error for playing 3 sounds at once when using the multigun powerup.
	if(this.playSound && !this.big[3]){
		this.fireSound.pause();
		this.fireSound.currentTime = 0;
		this.fireSound.play();
	}

	//play this sound if the bullet is of type big4
	if (this.big[3] && this.playSound) {
		this.bigBulletSound.pause();
		this.bigBulletSound.currentTime = 0;
		this.bigBulletSound.play();
	}

	/*
			// Diagnostics to check inheritance stuff
			this._bulletProperty = true;
			console.dir(this);
	*/

}

Bullet.prototype = new Entity();

// HACKED-IN AUDIO (no preloading)
Bullet.prototype.fireSound = new Audio(
	"sounds/shot.mp3");
Bullet.prototype.bigBulletSound = new Audio(
	"sounds/bigShot.mp3");

// Initial, inheritable, default values
Bullet.prototype.cx = 200;
Bullet.prototype.cy = 200;
Bullet.prototype.velX = 1;
Bullet.prototype.velY = 1;
Bullet.prototype.big;
Bullet.prototype.radius = 4;

// update the bullet
Bullet.prototype.update = function (du) {

	//unregister the bullet from spatial manager
	spatialManager.unregister(this);

	//Check if the bullet is dead or goes outside the canvas return the KILL_ME_NOW to the entity manager
	if (this._isDeadNow || this.cx > g_canvas.width) {
		return entityManager.KILL_ME_NOW;
	}

	//update the position of the bullet according to the velocity
	this.cx += this.velX * du;
	this.cy += this.velY * du;

	// Handle collisions
	// find the hit entity
	var hitEntity = this.findHitEntity();
	if (hitEntity) {
		var canTakeHit = hitEntity.takeBulletHit;
		if (canTakeHit) canTakeHit.call(hitEntity);


		// No bullet can pass through a wall
		if (hitEntity.typeOf === 'wall'){
				return entityManager.KILL_ME_NOW;
		}

		// Big bullets pass through enemies and all bullets pass through powerups
		if (!this.big[0] && !this.big[1] && !this.big[2] && !this.big[3] && hitEntity.typeOf !== 'superGun' && hitEntity.typeOf !== 'multiGun')
			return entityManager.KILL_ME_NOW;
			
	}

	//register the bullet in the spatial maanager
	spatialManager.register(this);

};

// returns the radius of the bullet
Bullet.prototype.getRadius = function () {
	return this.radius;
};

// render the bullet
Bullet.prototype.render = function (ctx) {

	//Check if the bullet is big, if it is then push in the sprite for big bullet nr 1
	if (this.big[0]) {
		g_sprites.bullet = new Sprite(g_images.bullet2, 0, 0, g_images.bullet2.width, g_images.bullet2.height);
		g_sprites.bullet.scale = 2;
	}
	//Check if the bullet is bigger, if it is then push in the sprite for big bullet nr 2
	else if (this.big[1]) {
		g_sprites.bullet = new Sprite(g_images.bullet3, 0, 0, g_images.bullet3.width, g_images.bullet3.height);
		g_sprites.bullet.scale = 2;
	}
	//Check if the bullet is even bigger, if it is then push in the sprite for big bullet nr 3
	else if (this.big[2]) {
		g_sprites.bullet = new Sprite(g_images.bullet4, 0, 0, g_images.bullet4.width, g_images.bullet4.height);
		g_sprites.bullet.scale = 2;
	}
	//Check if the bullet is the biggest, if it is then push in the sprite for big bullet nr 4
	else if (this.big[3]) {
		g_sprites.bullet = new Sprite(g_images.bullet5, 0, 0, g_images.bullet5.width, g_images.bullet5.height);
		g_sprites.bullet.scale = 2;
	}
	//Else push the sprite for a normal bullet
	else {
		g_sprites.bullet = new Sprite(g_images.bullet1, 0, 0, g_images.bullet1.width, g_images.bullet1.height);
		g_sprites.bullet.scale = 2;
	}

	//draw the bullet
	g_sprites.bullet.drawCentredAt(ctx, this.cx, this.cy, this.rotation);
};