These fractal trees were created by using L-systems and rendered in OpenGL.
variables : a b
constants : l r [ ]
axiom : b
rules : (a → a), (b → a[rb][lb])
angle : 20°
*tree shown with 11 recursions, I included commands to flip and re-draw the tree upside down upon completion
variables : f x y
constants : l r [ ]
axiom : x
rules : (f → ff), (x → fl[[xy]rxy]rf[rfxy]lx), (y → y)
angle : 22.5°
* tree shown with 6 recursions
variables : t s
constants : l r [ ]
axiom : ts
rules : (t → tt), (s → [s]r[s])
angle : (360/(numberOfRecursions + 1))°
* tree shown with 7 recursions