Kelley van Evert

L-systems #2 — using SVG

3D L-systems

Sutherland–Hodgman clipping to a triangle

The SVG arc command

The Recamán sequence

2D point in triangle test

The Kolakoski Sequence

Sacks number spiral

Projection of 3D Models using JavaScript and HTML5 Canvas

Visualizations

Four of the supported instructions are currently undocumented:
- "|": Rotate 180°
- "{": Begin polygon (dotted line)
- "}": End polygon (closes path)
- ".": Add polygon point

Fabian Iwand

How does your parser decide which of these "F" occurences is the draw/move command, and which is the nested system?

It's been a long time since I wrote this notebook, but I think what's happening is that the "F" has a "dual" role this way. One the one hand, it definitely causes a draw/move, on the other hand, it also expands syntactically.

Another way of viewing it, is that these L-systems are a two-stepped thing:
(1) The actual L-system expansion. So in this case, three times (+ or -1 haha) the initial string (F+F+F+F) is expanded via the rule.
(2) Then, we draw it, and now, indeed the "F" has a different connotation: that it draw/moves.

I'm curious: Why did you decide to leave the "animate: no" in? You implemented animate as a boolean flag, so "animate" and "animate: no" both enable the animation.