Am looking into writing up a Lindenmayer systems implementation. I've looked at a few example implementations and the one thing that's giving me trouble at this stage is how symbols and substitutions are meant to work (if this is even specified in the original treatise).
For example, the implementations I've seen tend in most cases to start with axioms based on A. Let's take the simplest example of this where the Axiom is (just) A.
When this is drawn (depth 0), what should I expect to see? If otherwise undefined, is A meant to render as anything at all? Or does it need to be defined as one full length (whichever symbol is used for this; I have seen pipe being used to this purpose) before it will render out?
Taking a second example, let us say that A renders out, irrespective of what the answer to the above is. If part of F's definition is B, and B is not defined, should B render as a full length?
The way I would expect this to work is that without F being defined at all, nothing should be drawn at depth 0 and subsequently at no other depth, either.