translate method
Translates by x pixels (horizontal) and y pixels (vertical).
Positive goes down/right.
Implementation
Matrix4Transform translate({double? x = 0, double? y = 0}) {
x ??= 0;
y ??= 0;
return (x == 0 && y == 0) //
? this
: Matrix4Transform._(m.clone()..leftTranslate(x, y));
}