Sector constructor
Creates a sector with the specified radius and central angle.
radius must be positive.
centralAngle is the angle of the sector.
center is the optional center point (defaults to origin).
Throws ArgumentError if radius is not positive.
Implementation
Sector(num radius, this.centralAngle, {Point? center})
: _radius = radius,
center = center ?? Point(0, 0),
super('Sector') {
if (radius <= 0) {
throw ArgumentError('Radius must be positive, got: $radius');
}
}