mirror of
https://github.com/nophead/Mendel90.git
synced 2025-01-16 12:29:46 +01:00
93 lines
3.1 KiB
Python
93 lines
3.1 KiB
Python
#!/usr/bin/env python
|
|
#
|
|
# OpenSCAD produces randomly ordered STL files so source control like GIT can't tell if they have changed or not.
|
|
# This scrip orders each triangle to start with the lowest vertex first (comparing x, then y, then z)
|
|
# It then sorts the triangles to start with the one with the lowest vertices first (comparing first vertex, second, then third)
|
|
# This has no effect on the model but makes the STL consistent. I.e. it makes a canonical form.
|
|
#
|
|
|
|
from __future__ import print_function
|
|
|
|
import sys
|
|
|
|
|
|
def _cmz(x):
|
|
''' Convert "-0" to "0". '''
|
|
return '0' if x == '-0' else x
|
|
|
|
|
|
class Vertex:
|
|
def __init__(self, x, y, z):
|
|
self.x, self.y, self.z = x, y, z
|
|
self.key = (float(x), float(y), float(z))
|
|
|
|
class Normal:
|
|
def __init__(self, dx, dy, dz):
|
|
self.dx, self.dy, self.dz = dx, dy, dz
|
|
|
|
class Facet:
|
|
def __init__(self, normal, v1, v2, v3):
|
|
self.normal = normal
|
|
if v1.key < v2.key:
|
|
if v1.key < v3.key:
|
|
self.vertices = (v1, v2, v3) #v1 is the smallest
|
|
else:
|
|
self.vertices = (v3, v1, v2) #v3 is the smallest
|
|
else:
|
|
if v2.key < v3.key:
|
|
self.vertices = (v2, v3, v1) #v2 is the smallest
|
|
else:
|
|
self.vertices = (v3, v1, v2) #v3 is the smallest
|
|
|
|
def key(self):
|
|
return (self.vertices[0].x, self.vertices[0].y, self.vertices[0].z,
|
|
self.vertices[1].x, self.vertices[1].y, self.vertices[1].z,
|
|
self.vertices[2].x, self.vertices[2].y, self.vertices[2].z)
|
|
|
|
class STL:
|
|
def __init__(self, fname):
|
|
self.facets = []
|
|
|
|
f = open(fname)
|
|
words = [_cmz(s.strip()) for s in f.read().split()]
|
|
f.close()
|
|
|
|
if words[0] == 'solid' and words[1] == 'OpenSCAD_Model':
|
|
i = 2
|
|
while words[i] == 'facet':
|
|
norm = Normal(words[i + 2], words[i + 3], words[i + 4])
|
|
v1 = Vertex(words[i + 8], words[i + 9], words[i + 10])
|
|
v2 = Vertex(words[i + 12], words[i + 13], words[i + 14])
|
|
v3 = Vertex(words[i + 16], words[i + 17], words[i + 18])
|
|
i += 21
|
|
self.facets.append(Facet(norm, v1, v2, v3))
|
|
|
|
self.facets.sort(key = Facet.key)
|
|
else:
|
|
print("Not an OpenSCAD ascii STL file")
|
|
sys.exit(1)
|
|
|
|
def write(self, fname):
|
|
f = open(fname,"wt")
|
|
print('solid OpenSCAD_Model', file=f)
|
|
for facet in self.facets:
|
|
print(' facet normal %s %s %s' % (facet.normal.dx, facet.normal.dy, facet.normal.dz), file=f)
|
|
print(' outer loop', file=f)
|
|
for vertex in facet.vertices:
|
|
print(' vertex %s %s %s' % (vertex.x, vertex.y, vertex.z), file=f)
|
|
print(' endloop', file=f)
|
|
print(' endfacet', file=f)
|
|
print('endsolid OpenSCAD_Model', file=f)
|
|
f.close()
|
|
|
|
def canonicalise(fname):
|
|
stl = STL(fname)
|
|
stl.write(fname)
|
|
|
|
if __name__ == '__main__':
|
|
if len(sys.argv) == 2:
|
|
canonicalise(sys.argv[1])
|
|
else:
|
|
print("usage: c14n_stl file")
|
|
sys.exit(1)
|