I thought I would be a bit clever and try to use my arcball gem in a sketch.
GEM_HOME = '/home/tux/.gem/ruby/2.6.0'
require 'arcball'
Processing::ArcBall.init(self)
def draw
clear
end
Unfortunately self is not the processing app so I get this error
Visor$$Layer_627236044 cannot be cast to processing.core.PApplet
However it filled me with optimism that I could use my gems with Visor, and in the first instance I created a custom gem to provide Vec2D and Vec3D to the Visor environment.
See result:-
