in toolkit/jb/shared.js [411:446]
function drawPixels(p, config, ctx, renderOptions) {
var pixels = config.pixels;
var blur = config.blur;
var contrast = Math.floor((config.contrast || 0) * 255);
var opacity = renderOptions.opacity;
if (!pixels) return;
p.push();
if (opacity) ctx.globalAlpha = opacity;
ctx.drawImage(pixels.canvas, 0, 0, pixels.width, pixels.height);
p.loadPixels();
var src = p.pixels; // pixels.values
var trg = p.pixels;
// console.log('copying', src.length, 'pixels to', pixels.length, 'pixels');
for (var i = 0; i < src.length; i += 4) {
trg[i] = src[i] - contrast ;
trg[i+1] = src[i+1] - contrast ;
trg[i+2] = src[i+2] - contrast;
trg[i+3] = src[i+3]/* * opacity */;
//trg[i] = src[i];
}
p.updatePixels();
if (blur) { p.filter(p.BLUR, blur); }
p.pop();
}