This is a 3D-version of bimanual tape drawing sometimes used in automotive drafting.
Holding the off-hand trigger down will constrain the brush to move in a straight line towards the off-hand controller.
You can curve the line by using your off-hand controller to control the stroke's direction while using your main-hand controller to move the cursor closer to the off-hand controller and control the stroke's orientation.
The Revolver adds a lathe function to the Wand Stroke Guide. Activate the Revolver by tapping the button marked with a bulls-eye icon while the Wand Stroke Guide is active.
The radius of the revolving arc constraint is dependent on the distance between the main hand controller and the Wand Stroke Guide Axis. You can tap the bulls-eye button to adjust the radius.
The revolver can also be made to automatically sweep around the axis by using the joystick.