Is there any way to simply draw in 3D, just like you would draw with ShapeRenderer or SpriteBatch? All I want is to draw circles that are in x.y.z coordinates, so some circles are far away from view and some are closer. Also I would like to be able to rotate these circles.
The simple way to draw in 3D is to wait until LibGDX has implemented their 3D functionality.
Otherwise, you can simulate the effect in 2D. Basically, you change the scale of the object to represent its movement along the Z-axis. Rotating would only be with respect to the current 2D perspective.