biker.js

function Biker(canvas) {

	this.canvas = canvas;
	this.canvas_context = canvas.getContext('2d');

    this.reset();

	this.width = 30;
	this.height = 40;

	this.movement = 10;
	this.boundary_margin = 32;

	this.image = new Image();
	this.image.src = "static/img/biker_large.png";

	this.sprite = sprite(this.canvas_context, 160, 64, this.image, 4, true);
}

Biker.prototype.reset = function(canvas) {
    this.x_position = this.canvas.width / 2;
    this.y_position = this. canvas.height / 6;
    this.atFinishLine = false;
    this.is_alive = true;
}

Biker.prototype.is_hit = function() {
	sound.play('crash');
	this.is_alive = false;
}


Biker.prototype.update = function(rightPressed, leftPressed, downPressed, upPressed, endOfLevel) {


	// compatible movements
		if (upPressed && this.upBoundaryCheck()) { // break
			this.y_position -= this.movement*0.5;
		}
		if (downPressed && this.downBoundaryCheck()) { // accelerate
			this.y_position += this.movement;
		}
		if (rightPressed && this.rightBoundaryCheck()) { // can also move right
			this.x_position += this.movement;
		}
		if (leftPressed && this.leftBoundaryCheck()) { // or left
			this.x_position -= this.movement;
		}
		// if both left and right, biker doesn't move in x-direction
	

	if (endOfLevel && (this.downBoundaryCheck() == false)) {
		this.atFinishLine = true;
	}

	this.sprite.update();
}


Biker.prototype.draw = function() {
	if (this.is_alive) {
		this.sprite.render(this.x_position, this.y_position);
	}
}

// returns true if illegal position
Biker.prototype.leftBoundaryCheck = function() {
	if (this.x_position + this.width/2 > (0 + boundary_margin)){
		return true;
	} return false;
}
Biker.prototype.rightBoundaryCheck = function() {
	if (this.x_position + this.width/2 < this.canvas.width - boundary_margin){
		return true;
	} return false;
}
Biker.prototype.upBoundaryCheck = function() {
	if (this.y_position + this.height/2 > 0 + boundary_margin){
		return true;
	} return false;
}
Biker.prototype.downBoundaryCheck = function() {
	if (this.y_position + this.height/2 < this.canvas.height - boundary_margin){
		return true;
	} return false;
}