Gravitational lensing refers to the deflection of light by the gravity of celestial bodies, often predominantly composed of dark matter. Seen through a gravitational lens, the images of distant galaxies appear distorted. A range of mathematical frameworks exist to model the lensing effect, but reconstructing the dark lens mass remains a difficult problem, where different models give different insight. This paper considers the Roulette formalism due to Chris Clarkson, and develops a simulator visualising the lensing effect according to the formalism. The objective is to enhance our understanding of the formalism in order to understand its strengths and limitation with respect to lens-mass modelling.