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JavaScript

Posted by Michael Fazekas
Michael Fazekas
Courses Plus Student 1,256 Points

trying to draw ball on canvas with js using objects?

I've been trying to draw a ball using JS objects and function on a canvas? its not showing anywhere on the canvas, not sure what im doing wrong or problem not asking google the right question..

const ruleBtn = document.querySelector('.rules-btn');
const closeBtn = document.querySelector('.close-btn');
const canvas = document.querySelector('canvas');
const ctx = canvas.getContext('2d');
const showRules = document.querySelector('.rules');

//create ball
const ball = {
    w: canvas.width / 2,
    y: canvas.height / 2,
    size: 10,
    speed: 5,
    dx: 4,
    dy: -4,
    visible: true
};

//draw ball function
function drawBall(){
    ctx.beginPath();
    ctx.arc(ball.x, ball.y, ball.size, 0, Math.PI*2);
    ctx.fillStyle = "#00000";
    ctx.fill();
    ctx.closePath();
}

****NOTE: this is not all the code just part of it. will post rest if you need it. thanks guys an gals!

2 Answers

Brandon White
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Brandon White
Full Stack JavaScript Techdegree Graduate 34,662 Points
Brandon White
.a{fill-rule:evenodd;}techdegree seal-36
Brandon White
Full Stack JavaScript Techdegree Graduate 34,662 Points

In the drawBall function you reference ball.x, but the ball object doesn’t have an x property. I think you meant for the w property in the ball object to be named x.

Think that may have something to do with your ball not showing up.

Michael Fazekas
Michael Fazekas
Courses Plus Student 1,256 Points

Thanks man! I have a bad habit of typos biggest thing that kills me lol I appreciate it!

Alan Brown
Alan Brown
20,524 Points
Alan Brown
Alan Brown
20,524 Points

Quick scan of your code. Your hex value for ctx.fillStyle is only 5 characters. I’m sure you have bigger things to address, but I would suggest fixing that first :-)