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JavaScript

Posted by Isaac Oleksiuk
Isaac Oleksiuk
Courses Plus Student 99 Points

I'm making "my first HTML 5 game". Following the video perfectly but JavaScript won't create a rectangle in the canvas?

I'm making "my first HTML 5 game". Following the video perfectly but JavaScript won't create a rectangle in the canvas? Here's the code,

var canvas = document.getElementById("canvas");
var context = canvas.getContext("2d");

imgFrog = new Image();
imgFrog.src = "images/mikethefrog.png";
imgFrog.addEventListener("load",init, false);

var requestAnimFrame =
                window.requestAnimationFrame ||
                window.webkitRequestAnimationFrame ||
                window.mozRequestAnimationFrame ||
                window.oRequestAnimationFrame ||
                window.msRequestAnimationFrame ||
                function (callback) {
                    window.setTimeout(callback, 1000/60);
                };

function init() {
    requestAnimFrame(update);
}

function update() {

    context.fillRect(  10, 10, 40, 380, "#000000");  


    requestAnimFrame(update);
}

1 Answer

Marcus Parsons
Marcus Parsons
15,719 Points
Marcus Parsons
Marcus Parsons
15,719 Points

Hey Isaac Oleksiuk,

The fillRect method only takes 4 parameters: x, y, width, height (respectively). You set the color with the fillStyle property like so:

//Either outside of the update() function like this:
context.fillStyle = "#000";
function update() {
    //Or you can do inside the update() function
    //It's up to you although it will be cached outside of the function
    //So that it doesn't get reset each time the function is called
    //context.fillStyle = "#000";
    context.fillRect(10, 10, 40, 380);  
    requestAnimFrame(update);
}