Function transparent

pattern/canvas.js:3198–3204

(img, alpha)

}

function transparent(img, alpha) {
    /* Returns a transparent version of the image.
     */
    return render(function(canvas) {
        image(img, {alpha: alpha});
    }, img.width, img.height);
}

function mask(img1, img2, dx, dy, alpha) {
    /* Applies the second image as an alpha mask to the first image.