I have been trying to use my constructor to apply individual colors to my Javascript balls. This challenge is from page 234 of the JavaScript for kids book. I have tried several methods. The closest solution I have come to is making the balls display a rainbow pattern(still cool but not what I want). I did that by writing this code======> ctx.fillstroke = this.color[Math.floor(Math.random() * this.color.length)]; inside my draw function . I would like to know how to apply one set color to each individual ball in my animation. Here is my code:
\\
Bouncing Ball var Ball = function () { this.x = 100; this.y = 100; this.xSpeed = Math.random() * 10 - 5; this.ySpeed = Math.random() * 10 - 5; this.color = ["Red","Orange", "Yellow", "Green", "Blue", "Purple"]; };var circle = function (x, y, radius, fillCircle){
ctx.beginPath();
ctx.arc(x, y, radius, 0, Math.PI * 2, false);
if (fillCircle) {
ctx.fill();
}else{
ctx.stroke();
}
};
Ball.prototype.draw = function () {
ctx.fillStyle = this.color;
circle(this.x, this.y, 3, true);
};
//This is what Is the function I used to randomly pick the color. It does not work.
var pick = function () {
return this.color[Math.floor(Math.random() * this.color.length)];
}
Ball.prototype.move = function () {
this.x += this.xSpeed;
this.y += this.ySpeed;
};
Ball.prototype.checkCollision = function () {
if (this.x < 0 || this.x > width) {
this.xSpeed = -this.xSpeed;
}
if (this.y < 0 || this.y > height) {
this.ySpeed = -this.ySpeed;
}
};
var newB = [];
for( var i = 0; i < 11; i++){
newB.push("Ball" + [i]);
}
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
//canvas size
var width = canvas.width;
var height = canvas.height;
for (var i = 0; i< newB.length; i++){
newB[i] = new Ball();
}
var ball = new Ball();
setInterval(function (){
ctx.clearRect(0, 0, width, height);
for (var i = 0; i < newB.length; i++){
newB[i].draw();
newB[i].move();
newB[i].checkCollision();
}
ctx.strokeRect(0, 0, width, height);
}, 30);
</script>
