References

1. Introduction to shape grammars SIGGRAPH 2008 Courses https://www.youtube.com/watch?v=k1EPPtNSYs8
2. How matrix utilize shape grammar in their building construction (https://www.youtube.com/watch?v=xLVJP-o0g28 - start from 05:00)
3. http://web.mit.edu/haldane/www/icerays/index.html

Definition

Shape grammar defines a specific class of production systems that generate geometric shapes (2- and 3- dimensional languages). In other words, it is a computation theory that defines a rule-based formalism to represent visual (and spatial) thinking.

There are three types of shape rule:

1. Start rule: to start the shape generation process
2. Transformation rule (at least one)
3. Termination rule: to make the shape generation process stop

One example transformation rule is see SHAPE_1, do SHAPE_2

• Left-Hand Side (LHS): depicts a condition in terms of a shape and a marker
• Right-Hand Side (RHS): depicts how LHS shape should be transformed and where the marker is positioned

Other examples

• iceray grammar (http://web.mit.edu/haldane/www/icerays/index.html)
  • Python: https://www.youtube.com/watch?v=jAEoqxL5IzA
• L-system → probably used in water system and tree system