Added examples/textures_sprite_anim.c

[IRooc]

The hardest thing in web still is loading an image and having the width and height available for you in a single function.

For the other part it all works, but if the image initially is not loaded quick enough it will be a wrong sprite offset because it falls back to 256 for width and height.

And yes Tsoding, i used the x = 0 || 256 operator ....

We should credit the Sprite Designer (which is done in the demo but in the source as well)
(c) Scarfy sprite by Eiden Marsal

[jkisor]

Tricky -- I think I found a way without waiting. #37
EDIT: Well, this example uses width/height data returned from LoadTexture -- which is yet to be implemented.

[IRooc]

Only synchronous option is the deprecated XMLHttpRequest one

function getImageDimensions(url) {
    let xhr = new XMLHttpRequest();
    xhr.overrideMimeType('text/plain; charset=x-user-defined'); //needed to not have unicode just ascii for the header part
    xhr.open('GET', url, false); // False for synchronous request
    xhr.send();
    
    if (xhr.status !== 200) {
        throw new Error('Failed to fetch image: ' + xhr.status);
    }
    
    let data = xhr.responseText;
    if (data.substr(1, 3) === 'PNG') {    
        let ihdr = data.indexOf('IHDR');
        if (ihdr === -1) {
            throw new Error('IHDR chunk not found');
        }
        var uint8 = Uint8Array.from(data.split("").map(x => x.charCodeAt()))
        let width = uint8[ihdr + 4] << 24 | uint8[ihdr + 5] << 16 | uint8[ihdr + 6] << 8 | uint8[ihdr + 7];
        let height = uint8[ihdr + 8] << 24 | uint8[ihdr + 9] << 16 | uint8[ihdr + 10] << 8 | uint8[ihdr + 11];
        return { width, height };
    }
    throw new Error('Not a supported image');
}