fadeTo method
Implementation
void fadeTo(Color color, double alpha, {bool family = true}) {
if (hasPoints()) {
var newColor = interpolateValue(getColor(), color, alpha);
setColor(color: newColor, family: false);
}
if (family) {
for (var submob in submobjects) {
submob.fadeTo(color, alpha, family: true);
}
}
}