Direction of rotation or handedness in three.js

Question

I've noticed that when I rotate my model around the Z axis, like this:

model.rotateZ(rotatedAngle * Math.PI / 180);

it seems to rotate counter-clockwise around the axis.

• Is this observation accurate?
• Is this documented somewhere? I couldn't find it, perhaps I'm using the wrong search terms.
• Is this configurable?
• Most importantly what is the best practice for managing rotations?

Answer 1

Three.js uses the right handed system and this means counter clockwise is default rotation. See here for all rotation rules...

Left the left handed system (clockwise), right the right handed system (counter clockwise)

So then adding something to your angle rotates counter clockwise and removing something rotates clockwise.

function rotate(){
    mesh1.rotation.z += 0.01;  // rotates counter clockwise
    mesh2.rotation.z -= 0.01;  // rotates clockwise
}

A Fiddle here to demonstrate