1 #!/usr/bin/env python
2 '''
3 Copyright (C) 2007 John Beard john.j.beard@gmail.com
5 ##This extension draws 3d objects from a Wavefront .obj 3D file stored in a local folder
6 ##Many settings for appearance, lighting, rotation, etc are available.
8 # ^y
9 # |
10 # __--``| |_--``| __--
11 # __--`` | __--``| |_--``
12 # | z | | |_--``|
13 # | <----|--------|-----_0-----|----------------
14 # | | |_--`` | |
15 # | __--`` <-``| |_--``
16 # |__--`` x |__--``|
17 # IMAGE PLANE SCENE|
18 # |
20 #Vertices are given as "v" followed by three numbers (x,y,z).
21 #All files need a vertex list
22 #v x.xxx y.yyy z.zzz
24 #Faces are given by a list of vertices
25 #(vertex 1 is the first in the list above, 2 the second, etc):
26 #f 1 2 3
28 #Edges are given by a list of vertices. These will be broken down
29 #into adjacent pairs automatically.
30 #l 1 2 3
32 #Faces are rendered according to the painter's algorithm and perhaps
33 #back-face culling, if selected. The parameter to sort the faces by
34 #is user-selectable between max, min and average z-value of the vertices
36 ######LICENCE#######
37 This program is free software; you can redistribute it and/or modify
38 it under the terms of the GNU General Public License as published by
39 the Free Software Foundation; either version 2 of the License, or
40 (at your option) any later version.
42 This program is distributed in the hope that it will be useful,
43 but WITHOUT ANY WARRANTY; without even the implied warranty of
44 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
45 GNU General Public License for more details.
47 You should have received a copy of the GNU General Public License
48 along with this program; if not, write to the Free Software
49 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
50 '''
52 import inkex
53 import simplestyle, sys, re
54 from math import *
55 try:
56 from numpy import *
57 except:
58 inkex.errormsg(_("Failed to import the numpy module. This module is required by this extension. Please install them and try again. On a Debian-like system this can be done with the command, sudo apt-get install python-numpy."))
59 sys.exit()
61 #FILE IO ROUTINES
62 def get_filename(self_options):
63 if self_options.obj == 'from_file':
64 file = self_options.spec_file
65 else:
66 file = self_options.obj + '.obj'
68 return file
70 def objfile(name):
71 import os.path
72 if __name__ == '__main__':
73 filename = sys.argv[0]
74 else:
75 filename = __file__
76 path = os.path.abspath(os.path.dirname(filename))
77 path = os.path.join(path, 'Poly3DObjects', name)
78 return path
80 def get_obj_data(obj, name):
81 infile = open(objfile(name))
83 #regular expressions
84 getname = '(.[nN]ame:\\s*)(.*)'
85 floating = '([\-\+\\d*\.e]*)' #a possibly non-integer number, with +/- and exponent.
86 getvertex = '(v\\s+)'+floating+'\\s+'+floating+'\\s+'+floating
87 getedgeline = '(l\\s+)(.*)'
88 getfaceline = '(f\\s+)(.*)'
89 getnextint = '(\\d+)([/\\d]*)(.*)'#we need to deal with 123\343\123 or 123\\456 as equivalent to 123 (we are ignoring the other options in the obj file)
91 for line in infile:
92 if line[0]=='#': #we have a comment line
93 m = re.search(getname, line) #check to see if this line contains a name
94 if m:
95 obj.name = m.group(2) #if it does, set the property
96 elif line[0] == 'v': #we have a vertex (maybe)
97 m = re.search(getvertex, line) #check to see if this line contains a valid vertex
98 if m: #we have a valid vertex
99 obj.vtx.append( [float(m.group(2)), float(m.group(3)), float(m.group(4)) ] )
100 elif line[0] == 'l': #we have a line (maybe)
101 m = re.search(getedgeline, line) #check to see if this line begins 'l '
102 if m: #we have a line beginning 'l '
103 vtxlist = [] #buffer
104 while line:
105 m2 = re.search(getnextint, line)
106 if m2:
107 vtxlist.append( int(m2.group(1)) )
108 line = m2.group(3)#remainder
109 else:
110 line = None
111 if len(vtxlist) > 1:#we need at least 2 vertices to make an edge
112 for i in range (len(vtxlist)-1):#we can have more than one vertex per line - get adjacent pairs
113 obj.edg.append( ( vtxlist[i], vtxlist[i+1] ) )#get the vertex pair between that vertex and the next
114 elif line[0] == 'f': #we have a face (maybe)
115 m = re.search(getfaceline, line)
116 if m: #we have a line beginning 'f '
117 vtxlist = []#buffer
118 while line:
119 m2 = re.search(getnextint, line)
120 if m2:
121 vtxlist.append( int(m2.group(1)) )
122 line = m2.group(3)#remainder
123 else:
124 line = None
125 if len(vtxlist) > 2: #we need at least 3 vertices to make an edge
126 obj.fce.append(vtxlist)
128 if obj.name == '':#no name was found, use filename, without extension (.obj)
129 obj.name = name[0:-4]
131 #RENDERING AND SVG OUTPUT FUNCTIONS
133 def draw_SVG_dot((cx, cy), st, name, parent):
134 style = { 'stroke': '#000000', 'stroke-width':str(st.th), 'fill': st.fill, 'stroke-opacity':st.s_opac, 'fill-opacity':st.f_opac}
135 circ_attribs = {'style':simplestyle.formatStyle(style),
136 inkex.addNS('label','inkscape'):name,
137 'r':str(st.r),
138 'cx':str(cx), 'cy':str(-cy)}
139 inkex.etree.SubElement(parent, inkex.addNS('circle','svg'), circ_attribs )
141 def draw_SVG_line((x1, y1),(x2, y2), st, name, parent):
142 style = { 'stroke': '#000000', 'stroke-width':str(st.th), 'stroke-linecap':st.linecap}
143 line_attribs = {'style':simplestyle.formatStyle(style),
144 inkex.addNS('label','inkscape'):name,
145 'd':'M '+str(x1)+','+str(-y1)+' L '+str(x2)+','+str(-y2)}
146 inkex.etree.SubElement(parent, inkex.addNS('path','svg'), line_attribs )
148 def draw_SVG_poly(pts, face, st, name, parent):
149 style = { 'stroke': '#000000', 'stroke-width':str(st.th), 'stroke-linejoin':st.linejoin, \
150 'stroke-opacity':st.s_opac, 'fill': st.fill, 'fill-opacity':st.f_opac}
151 for i in range(len(face)):
152 if i == 0:#for first point
153 d = 'M'#move to
154 else:
155 d = d + 'L'#line to
156 d = d+ str(pts[face[i]-1][0]) + ',' + str(-pts[face[i]-1][1])#add point
157 d = d + 'z' #close the polygon
159 line_attribs = {'style':simplestyle.formatStyle(style),
160 inkex.addNS('label','inkscape'):name,'d': d}
161 inkex.etree.SubElement(parent, inkex.addNS('path','svg'), line_attribs )
163 def draw_edges( edge_list, pts, st, parent ):
164 for edge in edge_list:#for every edge
165 pt_1 = pts[ edge[0]-1 ][0:2] #the point at the start
166 pt_2 = pts[ edge[1]-1 ][0:2] #the point at the end
167 name = 'Edge'+str(edge[0])+'-'+str(edge[1])
168 draw_SVG_line(pt_1,pt_2,st, name, parent)#plot edges
170 def draw_faces( faces_data, pts, obj, shading, fill_col,st, parent):
171 for face in faces_data:#for every polygon that has been sorted
172 if shading:
173 st.fill = get_darkened_colour(fill_col, face[1]/pi)#darken proportionally to angle to lighting vector
174 else:
175 st.fill = get_darkened_colour(fill_col, 1)#do not darken colour
177 face_no = face[3]#the number of the face to draw
178 draw_SVG_poly(pts, obj.fce[ face_no ], st, 'Face:'+str(face_no), parent)
180 def get_darkened_colour( (r,g,b), factor):
181 #return a hex triplet of colour, reduced in lightness proportionally to a value between 0 and 1
182 return '#' + "%02X" % floor( factor*r ) \
183 + "%02X" % floor( factor*g ) \
184 + "%02X" % floor( factor*b ) #make the colour string
186 def make_rotation_log(options):
187 #makes a string recording the axes and angles of each roation, so an object can be repeated
188 return options.r1_ax+str('%.2f'%options.r1_ang)+':'+\
189 options.r2_ax+str('%.2f'%options.r2_ang)+':'+\
190 options.r3_ax+str('%.2f'%options.r3_ang)+':'+\
191 options.r1_ax+str('%.2f'%options.r4_ang)+':'+\
192 options.r2_ax+str('%.2f'%options.r5_ang)+':'+\
193 options.r3_ax+str('%.2f'%options.r6_ang)
195 #MATHEMATICAL FUNCTIONS
196 def get_angle( vector1, vector2 ): #returns the angle between two vectors
197 return acos( dot(vector1, vector2) )
199 def length(vector):#return the pythagorean length of a vector
200 return sqrt(dot(vector,vector))
202 def normalise(vector):#return the unit vector pointing in the same direction as the argument
203 return vector / length(vector)
205 def get_normal( pts, face): #returns the normal vector for the plane passing though the first three elements of face of pts
206 #n = pt[0]->pt[1] x pt[0]->pt[3]
207 a = (array(pts[ face[0]-1 ]) - array(pts[ face[1]-1 ]))
208 b = (array(pts[ face[0]-1 ]) - array(pts[ face[2]-1 ]))
209 return cross(a,b).flatten()
211 def get_unit_normal(pts, face, cw_wound): #returns the unit normal for the plane passing through the first three points of face, taking account of winding
212 if cw_wound:
213 winding = -1 #if it is clockwise wound, reverse the vecotr direction
214 else:
215 winding = 1 #else leave alone
217 return winding*normalise(get_normal(pts, face))
219 def rotate( matrix, angle, axis ):#choose the correct rotation matrix to use
220 if axis == 'x':
221 matrix = rot_x(matrix, angle)
222 elif axis == 'y':
223 matrix = rot_y(matrix, angle)
224 elif axis == 'z':
225 matrix = rot_z(matrix, angle)
226 return matrix
228 def rot_z( matrix , a):#rotate around the z-axis by a radians
229 trans_mat = mat(array( [[ cos(a) , -sin(a) , 0 ],
230 [ sin(a) , cos(a) , 0 ],
231 [ 0 , 0 , 1 ]]))
232 return trans_mat*matrix
234 def rot_y( matrix , a):#rotate around the y-axis by a radians
235 trans_mat = mat(array( [[ cos(a) , 0 , sin(a) ],
236 [ 0 , 1 , 0 ],
237 [-sin(a) , 0 , cos(a) ]]))
238 return trans_mat*matrix
240 def rot_x( matrix , a):#rotate around the x-axis by a radians
241 trans_mat = mat(array( [[ 1 , 0 , 0 ],
242 [ 0 , cos(a) ,-sin(a) ],
243 [ 0 , sin(a) , cos(a) ]]))
244 return trans_mat*matrix
246 def get_transformed_pts( vtx_list, trans_mat):#translate the points according to the matrix
247 transformed_pts = []
248 for vtx in vtx_list:
249 transformed_pts.append((trans_mat * mat(vtx).T).T.tolist()[0] )#transform the points at add to the list
250 return transformed_pts
252 def get_max_z(pts, face): #returns the largest z_value of any point in the face
253 max_z = pts[ face[0]-1 ][2]
254 for i in range(1, len(face)):
255 if pts[ face[0]-1 ][2] >= max_z:
256 max_z = pts[ face[0]-1 ][2]
257 return max_z
259 def get_min_z(pts, face): #returns the smallest z_value of any point in the face
260 min_z = pts[ face[0]-1 ][2]
261 for i in range(1, len(face)):
262 if pts[ face[i]-1 ][2] <= min_z:
263 min_z = pts[ face[i]-1 ][2]
264 return min_z
266 def get_cent_z(pts, face): #returns the centroid z_value of any point in the face
267 sum = 0
268 for i in range(len(face)):
269 sum += pts[ face[i]-1 ][2]
270 return sum/len(face)
272 def get_z_sort_param(pts, face, method): #returns the z-sorting parameter specified by 'method' ('max', 'min', 'cent')
273 z_sort_param = ''
274 if method == 'max':
275 z_sort_param = get_max_z(pts, face)
276 elif method == 'min':
277 z_sort_param = get_min_z(pts, face)
278 else:
279 z_sort_param = get_cent_z(pts, face)
280 return z_sort_param
282 #OBJ DATA MANIPULATION
283 def remove_duplicates(list):#removes the duplicates from a list
284 list.sort()#sort the list
286 last = list[-1]
287 for i in range(len(list)-2, -1, -1):
288 if last==list[i]:
289 del list[i]
290 else:
291 last = list[i]
292 return list
294 def make_edge_list(face_list):#make an edge vertex list from an existing face vertex list
295 edge_list = []
296 for i in range(len(face_list)):#for every face
297 edges = len(face_list[i]) #number of edges around that face
298 for j in range(edges):#for every vertex in that face
299 new_edge = [face_list[i][j], face_list[i][(j+1)%edges] ]
300 new_edge.sort() #put in ascending order of vertices (to ensure we spot duplicates)
301 edge_list.append( new_edge )#get the vertex pair between that vertex and the next
303 return remove_duplicates(edge_list)
305 class Style(object): #container for style information
306 def __init__(self,options):
307 self.th = options.th
308 self.fill= '#ff0000'
309 self.col = '#000000'
310 self.r = 2
311 self.f_opac = str(options.f_opac/100.0)
312 self.s_opac = str(options.s_opac/100.0)
313 self.linecap = 'round'
314 self.linejoin = 'round'
316 class Obj(object): #a 3d object defined by the vertices and the faces (eg a polyhedron)
317 #edges can be generated from this information
318 def __init__(self):
319 self.vtx = []
320 self.edg = []
321 self.fce = []
322 self.name=''
324 def set_type(self, options):
325 if options.type == 'face':
326 if self.fce != []:
327 self.type = 'face'
328 else:
329 inkex.errormsg(_('No face data found in specified file\n'))
330 self.type = 'error'
331 else:
332 if self.edg != []:
333 self.type = 'edge'
334 else:
335 inkex.errormsg(_('No edge data found in specified file\n'))
336 obj.type = 'error'
338 class Poly_3D(inkex.Effect):
339 def __init__(self):
340 inkex.Effect.__init__(self)
341 self.OptionParser.add_option("--tab",
342 action="store", type="string",
343 dest="tab", default="object")
345 #MODEL FILE SETTINGS
346 self.OptionParser.add_option("--obj",
347 action="store", type="string",
348 dest="obj", default='cube')
349 self.OptionParser.add_option("--spec_file",
350 action="store", type="string",
351 dest="spec_file", default='great_rhombicuboct.obj')
352 self.OptionParser.add_option("--cw_wound",
353 action="store", type="inkbool",
354 dest="cw_wound", default='true')
355 self.OptionParser.add_option("--type",
356 action="store", type="string",
357 dest="type", default='face')
358 #VEIW SETTINGS
359 self.OptionParser.add_option("--r1_ax",
360 action="store", type="string",
361 dest="r1_ax", default=0)
362 self.OptionParser.add_option("--r2_ax",
363 action="store", type="string",
364 dest="r2_ax", default=0)
365 self.OptionParser.add_option("--r3_ax",
366 action="store", type="string",
367 dest="r3_ax", default=0)
368 self.OptionParser.add_option("--r4_ax",
369 action="store", type="string",
370 dest="r4_ax", default=0)
371 self.OptionParser.add_option("--r5_ax",
372 action="store", type="string",
373 dest="r5_ax", default=0)
374 self.OptionParser.add_option("--r6_ax",
375 action="store", type="string",
376 dest="r6_ax", default=0)
377 self.OptionParser.add_option("--r1_ang",
378 action="store", type="float",
379 dest="r1_ang", default=0)
380 self.OptionParser.add_option("--r2_ang",
381 action="store", type="float",
382 dest="r2_ang", default=0)
383 self.OptionParser.add_option("--r3_ang",
384 action="store", type="float",
385 dest="r3_ang", default=0)
386 self.OptionParser.add_option("--r4_ang",
387 action="store", type="float",
388 dest="r4_ang", default=0)
389 self.OptionParser.add_option("--r5_ang",
390 action="store", type="float",
391 dest="r5_ang", default=0)
392 self.OptionParser.add_option("--r6_ang",
393 action="store", type="float",
394 dest="r6_ang", default=0)
395 self.OptionParser.add_option("--scl",
396 action="store", type="float",
397 dest="scl", default=100.0)
398 #STYLE SETTINGS
399 self.OptionParser.add_option("--show",
400 action="store", type="string",
401 dest="show", default='faces')
402 self.OptionParser.add_option("--shade",
403 action="store", type="inkbool",
404 dest="shade", default='true')
405 self.OptionParser.add_option("--f_r",
406 action="store", type="int",
407 dest="f_r", default=255)
408 self.OptionParser.add_option("--f_g",
409 action="store", type="int",
410 dest="f_g", default=0)
411 self.OptionParser.add_option("--f_b",
412 action="store", type="int",
413 dest="f_b", default=0)
414 self.OptionParser.add_option("--f_opac",
415 action="store", type="int",
416 dest="f_opac", default=100)
417 self.OptionParser.add_option("--s_opac",
418 action="store", type="int",
419 dest="s_opac", default=100)
420 self.OptionParser.add_option("--th",
421 action="store", type="float",
422 dest="th", default=2)
423 self.OptionParser.add_option("--lv_x",
424 action="store", type="float",
425 dest="lv_x", default=1)
426 self.OptionParser.add_option("--lv_y",
427 action="store", type="float",
428 dest="lv_y", default=1)
429 self.OptionParser.add_option("--lv_z",
430 action="store", type="float",
431 dest="lv_z", default=-2)
432 self.OptionParser.add_option("--back",
433 action="store", type="inkbool",
434 dest="back", default='false')
435 self.OptionParser.add_option("--norm",
436 action="store", type="inkbool",
437 dest="norm", default='true')
438 self.OptionParser.add_option("--z_sort",
439 action="store", type="string",
440 dest="z_sort", default='min')
443 def effect(self):
444 so = self.options#shorthand
446 #INITIALISE AND LOAD DATA
448 obj = Obj() #create the object
449 file = get_filename(so)#get the file to load data from
450 get_obj_data(obj, file)#load data from the obj file
451 obj.set_type(so)#set the type (face or edge) as per the settings
453 st = Style(so) #initialise style
454 fill_col = (so.f_r, so.f_g, so.f_b) #colour tuple for the face fill
455 lighting = normalise( (so.lv_x,-so.lv_y,so.lv_z) ) #unit light vector
457 #INKSCAPE GROUP TO CONTAIN THE POLYHEDRON
459 #Put in in the centre of the current view
460 poly_transform = 'translate(' + str( self.view_center[0]) + ',' + str( self.view_center[1]) + ')'
461 #we will put all the rotations in the object name, so it can be repeated in
462 poly_name = obj.name+':'+make_rotation_log(so)
463 poly_attribs = {inkex.addNS('label','inkscape'):poly_name,
464 'transform':poly_transform }
465 poly = inkex.etree.SubElement(self.current_layer, 'g', poly_attribs)#the group to put everything in
467 #TRANFORMATION OF THE OBJECT (ROTATION, SCALE, ETC)
469 trans_mat = mat(identity(3, float)) #init. trans matrix as identity matrix
470 for i in range(1, 7):#for each rotation
471 axis = eval('so.r'+str(i)+'_ax')
472 angle = eval('so.r'+str(i)+'_ang') *pi/180
473 trans_mat = rotate(trans_mat, angle, axis)
474 trans_mat = trans_mat*so.scl #scale by linear factor (do this only after the transforms to reduce round-off)
476 transformed_pts = get_transformed_pts(obj.vtx, trans_mat) #the points as projected in the z-axis onto the viewplane
478 #RENDERING OF THE OBJECT
480 if so.show == 'vtx':
481 for i in range(len(transformed_pts)):
482 draw_SVG_dot([transformed_pts[i][0],transformed_pts[i][1]], st, 'Point'+str(i), poly)#plot points using transformed_pts x and y coords
484 elif so.show == 'edg':
485 if obj.type == 'face':#we must generate the edge list from the faces
486 edge_list = make_edge_list(obj.fce)
487 else:#we already have an edge list
488 edge_list = obj.edg
490 draw_edges( edge_list, transformed_pts, st, poly)
492 elif so.show == 'fce':
493 if obj.type == 'face':#we have a face list
495 z_list = []
497 for i in range(len(obj.fce)):
498 face = obj.fce[i] #the face we are dealing with
499 norm = get_unit_normal(transformed_pts, face, so.cw_wound) #get the normal vector to the face
500 angle = get_angle( norm, lighting )#get the angle between the normal and the lighting vector
501 z_sort_param = get_z_sort_param(transformed_pts, face, so.z_sort)
503 if so.back or norm[2] > 0: # include all polygons or just the front-facing ones as needed
504 z_list.append((z_sort_param, angle, norm, i))#record the maximum z-value of the face and angle to light, along with the face ID and normal
506 z_list.sort(lambda x, y: cmp(x[0],y[0])) #sort by ascending sort parameter of the face
507 draw_faces( z_list, transformed_pts, obj, so.shade, fill_col, st, poly)
509 else:#we cannot generate a list of faces from the edges without a lot of computation
510 inkex.errormsg(_('Face Data Not Found. Ensure file contains face data, and check the file is imported as "Face-Specifed" under the "Model File" tab.\n'))
511 else:
512 inkex.errormsg(_('Internal Error. No view type selected\n'))
514 if __name__ == '__main__':
515 e = Poly_3D()
516 e.affect()
519 # vim: expandtab shiftwidth=4 tabstop=8 softtabstop=4 encoding=utf-8 textwidth=99