Function extractAlpha

docs/app/js/sanddance-app.js:105802–105807

(alphaChannel, width, height, gridOuter, gridInner, radius, cutoff)

    }
}
function extractAlpha(alphaChannel, width, height, gridOuter, gridInner, radius, cutoff) {
    for(var i = 0; i < width * height; i++){
        var d = Math.sqrt(gridOuter[i]) - Math.sqrt(gridInner[i]);
        alphaChannel[i] = Math.round(255 - 255 * (d / radius + cutoff));
    }
}
TinySDF.prototype._draw = function(char, getMetrics) {
    var textMetrics = this.ctx.measureText(char);
    // Older browsers only expose the glyph width