ARC angle radius

Draws an arc (part of a circle) based on the turtle heading, turtle position, and inputs. The center-point of the arc is the turtle's current position. ARC does not move the turtle. The arc sweeps an amount given by the angle input. The size (curvature) of the arc is based on the radius input.

If radius is positive, then the arc starts radius turtle steps behind the turtle. If radius is negative, then the arc starts radius turtle steps in front of the turtle. In both cases, the arc sweeps an angle equal to the angle input. If angle is positive, then the arc is drawn in a clockwise direction. If angle is negative, then the arc is drawn in a counter-clockwise direction. If angle is 360 or greater (or -360 or less), then ARC draws a circle.

A 2D example:

ARC 360 100
ARC 90 50

A 3D example:

PERSPECTIVE
REPEAT 36 [RIGHTROLL 10 ARC 90 100]