What it does
Context Free generates geometric artwork from written rules saved in a CFDG file. Rules expand a starting shape into primitives or further shapes, with relative position, size, rotation and colour changes. The open-source program can render bitmap images, vector artwork or movies.
Describe how shapes relate
A small grammar can place a square and a smaller rotated copy:
startshape Tile
shape Tile {
SQUARE []
SQUARE [x 1.2 s 0.5 r 45]
}
The second shape moves right, scales down and rotates relative to its parent. Reusable rules can call other rules or call themselves, allowing recursive compositions. Variables, expressions, loops and custom paths add more control.
Retain the CFDG file to revise the design. In the command-line build, a render command names the grammar and output file; the documented example also sets output size. The desktop program provides another way to work with the same grammar.
Context Free is released under GPL version 2 or later. Its main creative requirement is comfort with writing rules rather than directly manipulating drawing objects.
Strengths
- Relative adjustments keep repeated shape relationships consistent
- Rules can be reused or recursively expanded
- The editable grammar remains separate from rendered output
Watch out for
- Creating artwork requires learning a written grammar
Best for
- Recursive geometric compositions
- Artists exploring rule-driven visual systems