I&#x27;ve written a few over the last 25 years as well, and it&#x27;s fun to write something that produces pretty pictures -- like drawing or playing an instrument is fun.<p>Currently I&#x27;m doing a C++ one that describes the model, colour handling and animation etc. using the type system directly rather than a traditional class hierarchy. <a href="https:&#x2F;&#x2F;github.com&#x2F;KayEss&#x2F;AnimRay" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;KayEss&#x2F;AnimRay</a>