rotateAngle method
Rotates teh matrix by given angle
Implementation
Matrix4 rotateAngle(double angle, {Offset? origin}) {
final angleRadians = angle * pi / 180;
if (angleRadians == 0.0) {
return this;
} else if ((origin == null) || (origin.dx == 0.0 && origin.dy == 0.0)) {
return this..rotateZ(angleRadians);
} else {
return this
..translate(origin.dx, origin.dy)
..multiply(Matrix4.rotationZ(angleRadians))
..translate(-origin.dx, -origin.dy);
}
}