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re: Why does the image not display on the canvas? VIEW POST

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re: Huh, it still doesn't draw nothing? But it's not null now, if it was before, I removed the display:none for images, and I added two lines to the on...

Yeah, my bad. Look at my previous comment, the problem isn't with the reassignment, it's with passing width and height to s.drawImage when they are undefined.

No, because doesn't undefined keep the original parameter

function f(x="Hi") {
console.log(x);
}

f(undefined);

result in:
Hi?

Yeah, but your default value for height and width is undefined. The function drawImage has several configurations of optional arguments, and it probably checks the length of the arguments to choose which strategy to apply. In your case, it is receiving five arguments, so it understands that it has to scale the image, but the scales are undefined.

You can try this to see what I mean:

const f = (...args) => console.log(args.length)
f(1, 2, 3) // 3
f(1, 2, 3, undefined, undefined) // 5

Ok, but how, then, can I resize the image (if I want or need) , but leave the parameters blank if the input value for that doesn't exist? Is there just no way to do that?

You could take the height and the width from the image if they are not provided.

const drawImg = function (src = null, x = 0, y = 0, width, height) {
    if (src === null) {
        return false;
    }
    let i = null;
    const draw = function () {
        const w = width || i.width
        const h = height || i.height
        s.drawImage(i, x, y, w, h);
    };
    i = img("textures/" + src + ".png", function () {
        alert();
        draw();
    });
    return true;
};

Ok, thanks, as I said, the default is it uses the image size, and the image did not appear when I ommited the width or height variables from the function call.......
For reference, this is what the image looks like:
postimg.cc/3kcW6Lqc

Nevermind, I ommited the width and height parameters from the s.drawImage function, and it still didn't appear.

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