static int randomLineWithColor_minLineWidth = 2;
static int randomLineWithColor_maxLineWidth = 20;
static double randomLineWithColor_maxThickness = 0.1;

static LineWithColor randomLineWithColor(int w, int h) {
  LineWithColor l = LineWithColor(randomPoint(w, h), randomPoint(w, h), randomColor());
  l.width = random_incl(randomLineWithColor_minLineWidth, randomLineWithColor_maxLineWidth);
  limitLineThickness(l, randomLineWithColor_maxThickness, randomLineWithColor_minLineWidth);
  ret l;
}

Began life as a copy of #1014956