1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
|
# add_mesh_gear.py (c) 2009, 2010 Michel J. Anders (varkenvarken)
#
# add gears/cogwheels to the blender 2.50 add->mesh menu
#
# tested with the official blender 2.50 alpha 0 32-bit windows
# also tested with trunk svn 26208 on 32-bit windows
#
# ##### BEGIN GPL LICENSE BLOCK #####
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
# ##### END GPL LICENSE BLOCK #####
bl_addon_info = {
'name': 'Add Mesh: Gears',
'author': 'varkenvarken',
'version': '2.1',
'blender': (2, 5, 3),
'location': 'View3D > Add > Mesh ',
'description': 'Adds a mesh Gear to the Add Mesh menu',
'url': 'http://wiki.blender.org/index.php/Extensions:2.5/Py/' \
'Scripts/Add_Mesh/Add_Gear',
'category': 'Add Mesh'}
"""
What was needed to port it from 2.49 -> 2.50 alpha 0?
The basic functions that calculate the geometry (verts and faces) are unchanged
( add_tooth(), add_spoke2(), add_gear() )
These functions were designed to return lists of tuples (x,y,z) (for the vertices) and
lists of lists [i,k,l,m] (for the faces). Because the Blender 2.50 API does not provide
facilties to alter individual elements of the the verts and faces attributes of a mesh
directly we have to add the calculated vertices and faces in bulk by using the
mesh.add_geometry(nverts,nedges,nfaces) methodfolowed by
mesh.verts.foreach_set("co", verts_loc) and mesh.faces.foreach_set("verts_raw", faces).
Both the foreach_set() methods take flattened lists as arguments, not lists of tuples, so we
added a simple function to flatten a list of lists or tuples.
Also, the vertex group API is changed a little bit but the concepts are the same:
vertexgroup = ob.add_vertex_group('NAME_OF_VERTEXGROUP') # add a vertex group
for i in vertexgroup_vertex_indices:
ob.add_vertex_to_group(i, vertexgroup, weight, 'ADD')
Now for some reason the name does not 'stick' and we have to set it this way:
vertexgroup.name = 'NAME_OF_VERTEXGROUP'
Conversion to 2.50 also meant we could simply do away with our crude user interface.
Just definining the appropriate properties in the AddGear() operator will display the
properties in the Blender GUI with the added benefit of making it interactive: changing
a property will redo the AddGear() operator providing the user with instant feedback.
FInally we had to convert/throw away some print statements to print functions as Blender
nows uses Python 3.x
The most puzzling issue was that the built in Python zip() function changed its behavior.
In 3.x it returns a zip object (that can be iterated over) instead of a list of tuples. This meant
we could no longer use deepcopy(zip(...)) but had to convert the zip object to a list of tuples
first.
The code to actually implement the AddGear() function is mostly copied from add_mesh_torus()
(distributed with Blender).
Unresolved issues:
- removing doubles:
the code that produces the teeth of the gears produces some duplicate vertices. The original
script just called remove_doubles() but if we do that in 2.50 we have a problem. To apply
the bpy.ops.mesh.remove_doubles() operator we have to change to edit mode. The moment
we do that we loose to possibilty to interactively change the properties. Also changing back
to object mode raises a strange exception (to investigate). So for now, removing doubles is left
to the user once satisfied with the chosen setting for a gear,
- no suitable icon:
a rather minor point but I reused the torus icon for the add->mesh->gear menu entry as there
doesn't seem to be a generic mesh icon or a way to add custom icons. Too bad, but as this is
just eye candy it's no big deal.
"""
import bpy
import mathutils
from math import cos, sin, tan, atan, asin, pi,radians as rad
from copy import deepcopy as dc
def flatten(alist):
"Flatten a list of lists or tuples."
return sum([list(a) for a in alist],[])
#constants
faces=[[0, 5, 6, 1],
[1, 6, 7, 2],
[2, 7, 8, 3],
[3, 8, 9, 4],
[6, 10, 11, 7],
[7, 11, 12, 8],
[10, 13, 14, 11],
[11, 14, 15, 12]]
L = 16 # number of vertices
#edgefaces
ef = [5, 6, 10, 13, 14, 15, 12, 8, 9]
ef2 = [i + L for i in ef]
# in python 3, zip() returns a zip object so we have to force the result into a list of lists to keep
# deepcopy happy later on in the script.
efc = [[i, j, k, l] for i, j, k, l in zip(ef[:-1], ef2[:-1], ef2[1:], ef[1:])]
vv = [5, 6, 8, 9, 21,22, 24, 25] #vertices in a valley
tv = [13, 14, 15, 29, 30, 31] #vertices on a tooth
spokefaces=((0, 1, 2, 5),
(2, 3, 4, 7),
(5, 2, 7, 6),
(5, 6, 9, 8),
(6, 7, 10, 9),
(11, 8, 13, 12),
(8, 9, 10, 13),
(13, 10, 15, 14))
def add_tooth(a, t, d, r, Ad, De, b, p, rack=0, crown=0.0):
"""
private function: calculate the vertex coords for a single side
section of a gear tooth. returns them as a list of lists.
"""
A = [a, a + t / 4, a + t / 2, a + 3 * t / 4, a + t]
C = [cos(i) for i in A]
S = [sin(i) for i in A]
Ra= r + Ad
Rd= r - De
Rb= Rd - b
#Pressure angle calc
O = Ad * tan(p)
p = atan(O/Ra)
if r < 0:
p = -p
if rack :
S =[sin(t/4)*I for I in range(-2,3)]
Sp=[0,sin(-t/4+p),0,sin(t/4-p)]
v = [(Rb, r * S[I], d) for I in range(5)]
v.extend([(Rd, r * S[I], d) for I in range(5)])
v.extend([(r, r * S[I], d) for I in range(1, 4)])
v.extend([(Ra, r * Sp[I], d) for I in range(1, 4)])
else:
Cp = [0, cos(a + t / 4 + p), cos(a + t / 2), cos(a + 3 * t / 4 - p)]
Sp = [0, sin(a + t / 4 + p), sin(a + t / 2), sin(a + 3 * t / 4 - p)]
v = [(Rb * C[I], Rb * S[I], d) for I in range(5)]
v.extend([(Rd * C[I], Rd * S[I], d) for I in range(5)])
v.extend([(r * C[I],r * S[I],d + crown / 3) for I in range(1, 4)])
v.extend([(Ra * Cp[I], Ra * Sp[I], d + crown) for I in range(1, 4)])
return v
def add_spoke2(a, t, d, r, De, b, s, w, l, gap=0, width=19):
"""
EXPERIMENTAL private function: calculate the vertex coords for a single side
section of a gearspoke. returns them as a list of lists.
"""
Rd=r - De
Rb=Rd - b
Rl=Rb
v = []
ef = []
ef2 = []
sf = []
if not gap :
for N in range(width, 1, -2) :
ef.append(len(v))
ts = t / 4
tm = a + 2 * ts
te = asin(w / Rb)
td = te - ts
t4 = ts + td * (width - N) / (width - 3.0)
A = [tm + (i - int(N / 2)) * t4 for i in range(N)]
C = [cos(i) for i in A]
S = [sin(i) for i in A]
v.extend([ (Rb * I, Rb * J, d) for (I, J) in zip(C,S)])
ef2.append(len(v) - 1)
Rb= Rb - s
n=0
for N in range(width, 3, -2):
sf.extend([(i + n,i + 1 + n,i + 2 + n,i + N + n) for i in range(0, N - 1, 2)])
sf.extend([(i + 2 + n,i + N + n,i + N + 1 + n,i + N + 2 + n) for i in range(0,N - 3,2)])
n = n + N
return v, ef, ef2, sf
def add_gear(N, r, Ad, De, b, p, D=1, skew=0, conangle=0, rack=0, crown=0.0, spoke=0, spbevel=0.1, spwidth=0.2, splength=1.0, spresol=9):
"""
"""
worm =0
if N < 5:
worm, N = N, 24
t = 2 * pi / N
if rack:
N=1
p = rad(p)
conangle = rad(conangle)
skew = rad(skew)
scale = (r - 2 * D * tan(conangle)) / r
f = []
v = []
tg= [] #vertexgroup of top vertices.
vg= [] #vertexgroup of valley vertices
M = [0]
if worm:
M, skew, D = (range(32), rad(11.25), D / 2)
for W in M:
fl = W * N * L * 2
l = 0 #number of vertices
for I in range(int(N)):
a = I * t
for (s, d, c, first) in ((W * skew, W * 2 * D - D, 1, 1),((W + 1) * skew, W * 2 * D + D, scale, 0)):
if worm and I % (int(N) / worm) != 0:
v.extend(add_tooth(a + s, t, d, r - De, 0.0, 0.0, b, p))
else:
v.extend(add_tooth(a + s, t, d, r * c, Ad * c, De * c, b * c, p, rack, crown))
if not worm or (W == 0 and first) or (W == (len(M) - 1) and not first) :
f.extend([ [j + l + fl for j in i] for i in dc(faces)])
l += L
#print (len(f))
#print (dc(efc))
f.extend([[j + I * L * 2 + fl for j in i] for i in dc(efc)])
#print (len(f))
tg.extend([i + I * L * 2 for i in tv])
vg.extend([i + I * L * 2 for i in vv])
# EXPERIMENTAL: add spokes
if not worm and spoke > 0:
fl=len(v)
for I in range(int(N)):
a = I * t
s = 0 # for test
if I % spoke == 0 :
for d in (-D, D) :
sv, ef, ef2, sf = add_spoke2(a + s, t, d, r * c, De * c, b * c, spbevel, spwidth, splength, 0, spresol)
v.extend(sv)
f.extend([[j + fl for j in i] for i in sf])
fl += len(sv)
d1 = fl - len(sv)
d2 = fl - 2 * len(sv)
f.extend([(i + d2, j + d2, j + d1, i + d1) for (i, j) in zip(ef[:-1], ef[1:])])
f.extend([(i + d2, j + d2, j + d1, i + d1) for (i, j) in zip(ef2[:-1], ef2[1:])])
else:
for d in (-D, D) :
(sv,ef,ef2,sf) = add_spoke2(a + s, t, d, r * c, De * c, b * c, spbevel, spwidth, splength, 1, spresol)
v.extend(sv)
fl += len(sv)
d1 = fl - len(sv)
d2 = fl - 2 * len(sv)
#f.extend([(i+d2,i+1+d2,i+1+d1,i+d1) for (i) in (0,1,2,3)])
#f.extend([(i+d2,i+1+d2,i+1+d1,i+d1) for (i) in (5,6,7,8)])
return flatten(v), flatten(f), tg, vg
from bpy.props import *
class AddGear(bpy.types.Operator):
'''Add a gear mesh.'''
bl_idname = "mesh.gear_add"
bl_label = "Add Gear"
bl_options = {'REGISTER', 'UNDO'}
number_of_teeth = IntProperty(name="Number of Teeth",
description="Number of teeth on the gear",
default=12, min=4, max=200)
radius = FloatProperty(name="Radius",
description="Radius of the gear, negative for crown gear",
default=1.0, min=-100.0, max=100.0)
addendum = FloatProperty(name="Addendum",
description="Addendum, extent of tooth above radius",
default=0.1, min=0.01, max=100.0)
dedendum = FloatProperty(name="Dedendum",
description="Dedendum, extent of tooth below radius",
default=0.1, min=0.0, max=100.0)
angle = FloatProperty(name="Pressure Angle",
description="Pressure angle, skewness of tooth tip (degrees)",
default=20.0, min=0.0, max=45.0)
base = FloatProperty(name="Base",
description="Base, extent of gear below radius",
default=0.2, min=0.0, max=100.0)
width = FloatProperty(name="Width",
description="Width, thickness of gear",
default=0.2, min=0.05, max=100.0)
skew = FloatProperty(name="Skewness",
description="Skew of teeth (degrees)",
default=0.0, min=-90.0, max=90.0)
conangle = FloatProperty(name="Conical angle",
description="Conical angle of gear (degrees)",
default=0.0, min=0.0, max=90.0)
crown = FloatProperty(name="Crown",
description="Inward pointing extend of crown teeth",
default=0.0, min=0.0, max=100.0)
def execute(self, context):
verts_loc, faces, tip_vertices, valley_vertices = add_gear(self.properties.number_of_teeth,
self.properties.radius,
self.properties.addendum,
self.properties.dedendum,
self.properties.base,
self.properties.angle,
self.properties.width,
skew=self.properties.skew,
conangle=self.properties.conangle,
crown=self.properties.crown)
#print(len(verts_loc)/3,faces)
mesh = bpy.data.meshes.new("Gear")
mesh.add_geometry(int(len(verts_loc) / 3), 0, int(len(faces) / 4))
mesh.verts.foreach_set("co", verts_loc)
mesh.faces.foreach_set("verts_raw", faces)
mesh.faces.foreach_set("smooth", [False] * len(mesh.faces))
scene = context.scene
# ugh (to quote the author of add_mesh_torus :-)
for ob in scene.objects:
ob.selected = False
mesh.update()
ob_new = bpy.data.objects.new('Gear', mesh)
tipgroup = ob_new.add_vertex_group('Tips')
# for some reason the name does not 'stick' and we have to set it this way:
tipgroup.name = 'Tips'
for i in tip_vertices:
ob_new.add_vertex_to_group(i, tipgroup, 1.0, 'ADD')
valleygroup = ob_new.add_vertex_group('Valleys')
# for some reason the name does not 'stick' and we have to set it this way:
valleygroup.name = 'Valleys'
for i in valley_vertices:
ob_new.add_vertex_to_group(i, valleygroup, 1.0, 'ADD')
scene.objects.link(ob_new)
scene.objects.active = ob_new
ob_new.selected = True
#print(1,bpy.context.mode)
#bpy.ops.object.mode_set(mode='EDIT')
#print(2,bpy.context.mode)
#bpy.ops.mesh.remove_doubles()
#print(3,bpy.context.mode)
# unfortunately the next line wont get us back to object mode but bombs
#bpy.ops.object.mode_set('OBJECT')
#print(4,bpy.context.mode)
ob_new.location = tuple(context.scene.cursor_location)
return {'FINISHED'}
# Add to a menu, reuse an icon used elsewhere that happens to have fitting name
# unfortunately, the icon shown is the one I expected from looking at the
# blenderbuttons file from the release/datafiles directory
menu_func = (lambda self, context: self.layout.operator(AddGear.bl_idname,
text="Gear", icon='PLUGIN'))
def register():
bpy.types.register(AddGear)
bpy.types.INFO_MT_mesh_add.append(menu_func)
def unregister():
bpy.types.unregister(AddGear)
bpy.types.INFO_MT_mesh_add.remove(menu_func)
# Remove "Gears" menu from the "Add Mesh" menu.
#space_info.INFO_MT_mesh_add.remove(menu_func)
if __name__ == "__main__":
register()
|