Editor.Drawing.Context.globalAlpha = 0.3;
var amount = 3;

for(var t = -amount; t <= amount; t += 3) {
    for(var n = -amount; n <= amount; n += 3) {
        Editor.Drawing.Context.drawImage(Editor.Drawing.ClipCanvas, -(n-1), -(t-1));
    }
}

function brushLine(ctx, x1, y1, x2, y2) {

    var diffX = Math.abs(x2 - x1),                       // calc diffs
        diffY = Math.abs(y2 - y1),
        dist = Math.sqrt(diffX * diffX + diffY * diffY), // find length
        step = 20 / (dist ? dist : 1),                   // "resolution"
        i = 0,                                           // iterator for length
        t = 0,                                           // t [0, 1]
        b, x, y;

    while (i <= dist) {
      t = Math.max(0, Math.min(1, i / dist));
      x = x1 + (x2 - x1) * t;
      y = y1 + (y2 - y1) * t;
      b = (Math.random() * 3) | 0;
      ctx.drawImage(brush, x - bw * 0.5, y - bh * 0.5);  // draw brush
      i += step;
    }
}