Same as the classic L systems, that works in polar coordinates (turtle) -- this one is extended into spherical. (3D turtle)
the angle exists as an azimuth and an elevation.
Written in PLT Scheme (those are all recursive patterns ) , had to write the string parser myself -- have to correct it , it doesn't know what to do with double spaces (have to write an extra filter).
but it's already working , testing for the moment
best, Rob
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