Handles.DrawWireArc

static function DrawWireArc (center : Vector3, normal : Vector3, from : Vector3, angle : float, radius : float) : void

Parameters

Name	Description
center	the center of the circle
normal	the normal of the circle
from	the direction of the point on the circle circumference, relative to the center, where the arc begins
angle	the angle of the arc, in degrees
radius	the radius of the circle Note: Use HandleUtility.GetHandleSize where you might want to have constant screen-sized handles.

Description

Draw a circular arc in 3D space.

Wire Arc in the Scene View.

// Create a 180 degrees wire arc with a ScaleValueHandle attached to the disc
// that lets you modify the "shieldArea" var in the WireArcExample.js

@CustomEditor (WireArcExample)
class DrawWireArc extends Editor {
    function OnSceneGUI () {
        Handles.color = Color.red;
        Handles.DrawWireArc(target.transform.position, 
            target.transform.up, 
            -target.transform.right, 
            180, 
            target.shieldArea);
        
        target.shieldArea = 
        Handles.ScaleValueHandle(target.shieldArea,
                        target.transform.position + target.transform.forward*target.shieldArea,
                        target.transform.rotation,
                        1,
                        Handles.ConeCap,
                        1);
    }
}

And the script attached to this Handle:

// WireArcExample.js

var shieldArea : float = 5;