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How to express contextual design grammar as internal DSL in Python?

[Note: re-reading this before posting, I realized that this Q was a bit of an epic. Thank you for condoning my long explanation of the reasons for this persecution. I feel that if I were able to help other beginning similar projects, I would be more likely to board if I knew what the motivation was.]

I recently got into the Structure Synth of Michael Hviddfeldt Christensen. This is a tool for creating 3D geometry from (predominantly) context free Eisenscript grammar. The Synth structure itself is inspired by contextual art. Contextual free grammars can produce stunning results from surprisingly simple rule sets.

My current Structure Synth workflow includes exporting an OBJ file from Structure Synth, importing it into Blender, setting up lights, materials, etc., and then rendering with Luxrender. Unfortunately, importing these OBJ files often causes Blender to stop, as there may be thousands of objects with fairly complex geometry. I say honestly because Structure Synth only generates basic shapes, but the sphere represented by triangles still has many faces.

Thus, creating structures directly in Blender would be preferable to the current process (deep Blender support for Python scripts should make this possible). The Python Intelligent Library can use Blender's capabilities to create a single grid to create multiple objects, thereby saving memory. Plus Blender is a full-featured 3D package, and its ability to interpret CFDGs will provide creativity far beyond what Structure Synth can offer.

And so my question is how best to translate Eisenscript grammar into Python DSL. Here's what simple Eisenscript looks like:

set maxdepth 2000
{ a 0.9 hue 30 } R1 

rule R1 { 
  { x 1  rz 3 ry 5  } R1
  { s 1 1 0.1 sat 0.9 } box
}

rule R1 { 
  { x 1  rz -3 ry 5  } R1
  { s 1 1 0.1 } box
}

, R1 ( 2) R1. R1 R1 ( ), . , 2000.

( CoffeeScript) - DSL Ruby . , - , .

Eisenscript Ruby DSL :

rule :r1 do
  r1 :x => 1, :rz => 3, :ry => 5
  box :s => [1, 1, 0.1], :sat => 0.9
end

rule :r1 do
  r1 :x => 1, :rz => -3, :ry => 5
  box :s => [1, 1, 0.1]
end

Python Python. , , DSL , , , - ?

Pythonista ?

+5
2

, Ruby , ContextFree, , , . . ; Python, Ruby Python.

import random

class ContextFree(object):
  def __init__(self):
    self.rules = {}
    # grab any instancemethod to get an instance of the instancemethod class
    self.instancemethod = type(self.add_rule)
    self.max_depth = 100
    self.depth = 0

  def add_rule(self, func, prob=1):
    rule_name = func.__name__

    if not rule_name in self.rules:
      self.rules[rule_name] = { 'funcs' : [], 'total' : 0 }

    total = self.rules[rule_name]['total']
    self.rules[rule_name]['funcs'].append([range(total,(prob+total)), func])
    self.rules[rule_name]['total'] += prob

    def augmented_func(self, options={}):
      if not self.depth >= self.max_depth:
        self.depth += 1
        pick = self.determine_rule(rule_name)
        print('Generation', self.depth)
        pick(self)

    self.__dict__[rule_name] = self.instancemethod(augmented_func, self)

  def determine_rule(self, rule_name):
    rule = self.rules[rule_name]
    winning_number = random.randrange(0, self.rules[rule_name]['total'])
    for func in rule['funcs']:
      if winning_number in func[0]:
        return func[1]

cf = ContextFree()

def box(self):
  print('Rule for box1')
  self.box()

cf.add_rule(box)

def box(self):
  print('Rule for box2')
  self.box()

cf.add_rule(box)

cf.box()

# Output:
## Generation 1
## Rule for box2
## Generation 2
## Rule for box2
## Generation 3
## Rule for box1
## Generation 4
## Rule for box2
## Generation 5
## Rule for box1
## Generation 6
## Rule for box2
## Generation 7
## Rule for box2
## Generation 8
## Rule for box1
## Generation 9
## Rule for box2
## Generation 10
## Rule for box2
## Generation 11
## Rule for box1
## Generation 12
## Rule for box1
## Generation 13
## Rule for box1
## Generation 14
## Rule for box1
## Generation 15
## Rule for box2
## Generation 16
## Rule for box1
## Generation 17
## Rule for box1
## Generation 18
## Rule for box1
## Generation 19
## Rule for box1
## Generation 20
## Rule for box1
## Generation 21
## Rule for box2
## Generation 22
## Rule for box2
## Generation 23
## Rule for box1
## Generation 24
## Rule for box2
## Generation 25
## Rule for box1
## Generation 26
## Rule for box2
## Generation 27
## Rule for box2
## Generation 28
## Rule for box1
## Generation 29
## Rule for box2
## Generation 30
## Rule for box2
## Generation 31
## Rule for box2
## Generation 32
## Rule for box2
## Generation 33
## Rule for box2
## Generation 34
## Rule for box1
## Generation 35
## Rule for box2
## Generation 36
## Rule for box1
## Generation 37
## Rule for box1
## Generation 38
## Rule for box1
## Generation 39
## Rule for box1
## Generation 40
## Rule for box2
## Generation 41
## Rule for box1
## Generation 42
## Rule for box1
## Generation 43
## Rule for box1
## Generation 44
## Rule for box1
## Generation 45
## Rule for box2
## Generation 46
## Rule for box1
## Generation 47
## Rule for box2
## Generation 48
## Rule for box1
## Generation 49
## Rule for box2
## Generation 50
## Rule for box1
## Generation 51
## Rule for box1
## Generation 52
## Rule for box1
## Generation 53
## Rule for box2
## Generation 54
## Rule for box2
## Generation 55
## Rule for box2
## Generation 56
## Rule for box2
## Generation 57
## Rule for box2
## Generation 58
## Rule for box1
## Generation 59
## Rule for box1
## Generation 60
## Rule for box1
## Generation 61
## Rule for box2
## Generation 62
## Rule for box2
## Generation 63
## Rule for box2
## Generation 64
## Rule for box1
## Generation 65
## Rule for box2
## Generation 66
## Rule for box2
## Generation 67
## Rule for box2
## Generation 68
## Rule for box2
## Generation 69
## Rule for box2
## Generation 70
## Rule for box1
## Generation 71
## Rule for box2
## Generation 72
## Rule for box2
## Generation 73
## Rule for box2
## Generation 74
## Rule for box1
## Generation 75
## Rule for box2
## Generation 76
## Rule for box1
## Generation 77
## Rule for box1
## Generation 78
## Rule for box2
## Generation 79
## Rule for box1
## Generation 80
## Rule for box2
## Generation 81
## Rule for box1
## Generation 82
## Rule for box1
## Generation 83
## Rule for box1
## Generation 84
## Rule for box1
## Generation 85
## Rule for box2
## Generation 86
## Rule for box1
## Generation 87
## Rule for box1
## Generation 88
## Rule for box2
## Generation 89
## Rule for box2
## Generation 90
## Rule for box1
## Generation 91
## Rule for box1
## Generation 92
## Rule for box1
## Generation 93
## Rule for box1
## Generation 94
## Rule for box1
## Generation 95
## Rule for box1
## Generation 96
## Rule for box2
## Generation 97
## Rule for box1
## Generation 98
## Rule for box2
## Generation 99
## Rule for box1
## Generation 100
## Rule for box2
+3

. , , - , .

PyParsing. , SQL, , , .

+4

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