mesh_export.py

   1 #!BPY
   2 # $Id$
   3
   4 """
   5 Name: 'MSP GL Mesh (.mesh)...'
   6 Blender: 244
   7 Group: 'Export'
   8 """
   9
  10 import sys
  11 import math
  12 import bpy
  13 import Blender
  14
  15 def make_edge_key(i1, i2):
  16         return (min(i1, i2), max(i1, i2))
  17
  18
  19 class Edge:
  20         def __init__(self, me):
  21                 if me.__class__==Edge:
  22                         self._medge=me._medge
  23                         self.v1=me.v1
  24                         self.v2=me.v2
  25                         self.smooth=me.smooth
  26                 else:
  27                         self._medge=me
  28                         self.smooth=False
  29                 self.faces=[]
  30
  31         def __getattr__(self, attr):
  32                 return getattr(self._medge, attr)
  33
  34         def __cmp__(self, other):
  35                 return self is other
  36
  37         def check_smooth(self, limit):
  38                 if len(self.faces)!=2:
  39                         return
  40
  41                 d=Blender.Mathutils.DotVecs(self.faces[0].no, self.faces[1].no)
  42                 if (d>limit and self.faces[0].smooth and self.faces[1].smooth) or d>0.999:
  43                         self.smooth=True
  44
  45         def other_face(self, f):
  46                 if f.index==self.faces[0].index:
  47                         if len(self.faces)>=2:
  48                                 return self.faces[1]
  49                         else:
  50                                 return None
  51                 else:
  52                         return self.faces[0]
  53
  54
  55 class Vertex:
  56         def __init__(self, mv):
  57                 if mv.__class__==Vertex:
  58                         self._mvert=mv._mvert
  59                         self.no=mv.no
  60                         self.uv=mv.uv
  61                 else:
  62                         self._mvert=mv
  63                         self.uv=None
  64                 self.orig_index=self._mvert.index
  65                 self.flag=False
  66                 self.faces=[]
  67                 self.tan=None
  68                 self.bino=None
  69
  70         def __getattr__(self, attr):
  71                 return getattr(self._mvert, attr)
  72
  73         def __cmp__(self, other):
  74                 if other is None:
  75                         return 1
  76                 return cmp(self.index, other.index)
  77
  78         def __str__(self):
  79                 return "<Vert %d (%.4f, %.4f, %.4f) (%.4f, %.4f, %.4f)>"%(self.index, self.co[0], self.co[1], self.co[2], self.no[0], self.no[1], self.no[2])
  80
  81         __repr__=__str__
  82
  83
  84 class Face:
  85         def __init__(self, mf):
  86                 self._mface=mf
  87                 self.edges=[]
  88                 self.verts=[v for v in mf.verts]
  89                 self.flag=False
  90
  91         def __getattr__(self, attr):
  92                 return getattr(self._mface, attr)
  93
  94         def __cmp__(self, other):
  95                 if other is None:
  96                         return 1
  97                 return cmp(self.index, other.index)
  98
  99         def __str__(self):
 100                 return "<Face %d (%s)>"%(self.index, " ".join([str(v.index) for v in self.verts]))
 101
 102         __repr__=__str__
 103
 104         def pivot_vertices(self, reverse, *vt):
 105                 verts=self.verts[:]
 106                 if reverse:
 107                         verts.reverse()
 108                 flags=[(v in vt) for v in verts]
 109                 l=len(verts)
 110                 for i in range(l):
 111                         if flags[i] and not flags[(i+l-1)%l]:
 112                                 return verts[i:]+verts[:i]
 113
 114         def get_edge(self, v1, v2):
 115                 key=make_edge_key(v1.index, v2.index)
 116                 for e in self.edges:
 117                         if e.key==key:
 118                                 return e
 119                 raise KeyError, "No edge %s"%(key,)
 120
 121
 122 class Line:
 123         def __init__(self, e):
 124                 self.edge=e
 125                 self.verts=[e.v1, e.v2]
 126                 self.flag=False
 127
 128         def __str__(self):
 129                 return "<Line (%d %d)>"%(self.verts[0].index, self.verts[1].index)
 130
 131         __repr__=__str__
 132
 133
 134 class Mesh:
 135         def __init__(self, m):
 136                 self._mesh=m
 137                 self.verts=[Vertex(v) for v in m.verts]
 138                 self.faces=[Face(f) for f in m.faces]
 139
 140                 for f in self.faces:
 141                         for i in range(len(f.verts)):
 142                                 f.verts[i]=self.verts[f.verts[i].index]
 143                                 f.verts[i].faces.append(f)
 144
 145                 self.edges=dict([(e.key, Edge(e)) for e in m.edges])
 146                 for f in self.faces:
 147                         for k in f.edge_keys:
 148                                 e=self.edges[k]
 149                                 e.faces.append(self.faces[f.index])
 150                                 f.edges.append(e)
 151
 152                 self.lines=[Line(e) for e in self.edges.itervalues() if not e.faces]
 153
 154                 smooth_limit=math.cos(m.degr*math.pi/180)
 155                 for e in self.edges.itervalues():
 156                         e.v1=self.verts[e.v1.index]
 157                         e.v2=self.verts[e.v2.index]
 158                         e.check_smooth(smooth_limit)
 159
 160         def __getattr__(self, attr):
 161                 return getattr(self._mesh, attr)
 162
 163         def split_vertices(self, find_group_func, debug):
 164                 groups=[]
 165                 for v in self.verts:
 166                         for f in v.faces:
 167                                 f.flag=False
 168
 169                         vg=[]
 170                         for f in v.faces:
 171                                 if not f.flag:
 172                                         vg.append(find_group_func(v, f))
 173
 174                         groups.append(vg)
 175
 176                 for i in range(len(self.verts)):
 177                         if len(groups[i])==1:
 178                                 continue
 179
 180                         if debug:
 181                                 print "Vertex %s has %d groups"%(self.verts[i], len(groups[i]))
 182
 183                         for g in groups[i][1:]:
 184                                 v=Vertex(self.verts[i])
 185                                 v.index=len(self.verts)
 186                                 self.verts.append(v)
 187
 188                                 if debug:
 189                                         print "  -> %d %s"%(v.index, [f.index for f in g])
 190
 191                                 for f in g:
 192                                         for j in range(len(f.edges)):
 193                                                 e=f.edges[j]
 194
 195                                                 if e.v1!=self.verts[i] and e.v2!=self.verts[i]:
 196                                                         continue
 197
 198                                                 if debug:
 199                                                         print "  Splitting edge %s with faces %s"%(e.key, e.faces)
 200
 201                                                 if e.other_face(f) not in g and len(e.faces)>=2:
 202                                                         k=e.faces.index(f)
 203                                                         e.faces.remove(f)
 204                                                         e=Edge(e)
 205                                                         f.edges[j]=e
 206                                                         e.faces.append(f)
 207                                                 else:
 208                                                         del self.edges[e.key]
 209
 210                                                 if e.v1==self.verts[i]:
 211                                                         e.v1=v
 212                                                 elif e.v2==self.verts[i]:
 213                                                         e.v2=v
 214
 215                                                 e.key=make_edge_key(e.v1.index, e.v2.index)
 216                                                 self.edges[e.key]=e
 217
 218                                         self.verts[i].faces.remove(f)
 219                                         f.verts[f.verts.index(self.verts[i])]=v
 220                                         v.faces.append(f)
 221
 222         def split_smooth(self, debug=False):
 223                 self.split_vertices(self.find_smooth_group, debug)
 224
 225         def split_uv(self, debug=False):
 226                 self.split_vertices(self.find_uv_group, debug)
 227
 228         def find_smooth_group(self, vert, face):
 229                 face.flag=True
 230                 queue=[face]
 231
 232                 for f in queue:
 233                         for e in f.edges:
 234                                 other=e.other_face(f)
 235                                 #if not other or other.index not in face_indices:
 236                                 if other not in vert.faces:
 237                                         continue
 238
 239                                 if e.smooth:
 240                                         if not other.flag:
 241                                                 other.flag=True
 242                                                 queue.append(other)
 243
 244                 return queue
 245
 246         def find_uv_group(self, vert, face):
 247                 uv=face.uv[face.verts.index(vert)]
 248                 face.flag=True
 249                 group=[face]
 250                 for f in vert.faces:
 251                         if not f.flag and f.uv[f.verts.index(vert)]==uv:
 252                                 f.flag=True
 253                                 group.append(f)
 254                 return group
 255
 256         def compute_normals(self):
 257                 for v in self.verts:
 258                         if v.faces:
 259                                 v.no=Blender.Mathutils.Vector()
 260                                 for f in v.faces:
 261                                         v.no+=f.no
 262                                 v.no.normalize()
 263                         else:
 264                                 # XXX Should use edges to compute normal
 265                                 v.no=Blender.Mathutils.Vector(0, 0, 1)
 266
 267         def compute_uv(self):
 268                 for v in self.verts:
 269                         if v.faces:
 270                                 v.uv=v.faces[0].uv[v.faces[0].verts.index(v)]
 271
 272         def compute_tbn(self):
 273                 for v in self.verts:
 274                         v.tan=Blender.Mathutils.Vector()
 275                         v.bino=Blender.Mathutils.Vector()
 276                         for f in v.faces:
 277                                 fverts=f.pivot_vertices(False, v)
 278                                 v1=fverts[1]
 279                                 v2=fverts[-1]
 280                                 du1=v1.uv[0]-v.uv[0]
 281                                 du2=v2.uv[0]-v.uv[0]
 282                                 dv1=v1.uv[1]-v.uv[1]
 283                                 dv2=v2.uv[1]-v.uv[1]
 284                                 div=du1*dv2-du2*dv1
 285                                 edge1=fverts[1].co-fverts[0].co
 286                                 edge2=fverts[-1].co-fverts[0].co
 287                                 v.tan+=(edge1*dv2-edge2*dv1)/div
 288                                 v.bino+=(edge2*du1-edge1*du2)/div
 289                         v.tan.normalize()
 290                         v.bino.normalize()
 291
 292         def create_strip(self, face, reverse, debug):
 293                 edge=None
 294                 for e in face.edges:
 295                         other=e.other_face(face)
 296                         if other and not other.flag:
 297                                 edge=e
 298                                 break
 299
 300                 if not edge:
 301                         return None
 302
 303                 if debug:
 304                         print "Starting strip from %s, edge %s, reverse=%s"%([v.index for v in face.verts], (edge.v1.index, edge.v2.index), reverse)
 305
 306                 verts=face.pivot_vertices(reverse, edge.v1, edge.v2)
 307                 if len(verts)==3:
 308                         result=[verts[-1], verts[0]]
 309                 else:
 310                         result=[verts[-2], verts[-1]]
 311
 312                 while 1:
 313                         verts=face.pivot_vertices(reverse, *result[-2:])
 314                         k=len(result)%2
 315                         if debug:
 316                                 print "  Adding %s"%face
 317
 318                         face.flag=True
 319                         if len(verts)==4 and not k:
 320                                 result.append(verts[3])
 321                         result.append(verts[2])
 322                         if len(verts)==4 and k:
 323                                 result.append(verts[3])
 324
 325                         edge=face.get_edge(*result[-2:])
 326
 327                         if debug:
 328                                 print "  Next edge is %s"%(edge.key, )
 329
 330                         next=edge.other_face(face)
 331                         if not next or next.flag:
 332                                 break
 333                         face=next
 334
 335                 if debug:
 336                         print "  %s"%[v.index for v in result]
 337
 338                 return result
 339
 340
 341 class Exporter:
 342         def __init__(self, fn):
 343                 self.filename=fn
 344                 if fn==None:
 345                         self.out_file=sys.stdout
 346                 else:
 347                         self.out_file=file(fn, "w")
 348                 self.use_strips=True
 349                 self.use_degen_tris=True
 350                 self.optimize_locality=True
 351                 self.export_lines=True
 352                 self.tbn_vecs=False
 353                 self.debug=False
 354                 self.strip_debug=False
 355                 self.split_debug=False
 356
 357         def get_locality(self, strip):
 358                 total=0
 359                 for i in range(1, len(strip)):
 360                         if strip[i].index!=strip[i-1].index:
 361                                 total+=1.0/(abs(strip[i].index-strip[i-1].index))
 362                 return total/len(strip)
 363
 364         def get_followers(self, strip):
 365                 result={}
 366                 for i in range(len(strip)-1):
 367                         v=strip[i]
 368                         n=strip[i+1]
 369                         if v.index!=n.index:
 370                                 if v.index not in result:
 371                                         result[v.index]={}
 372                                 if n.index not in result[v.index]:
 373                                         result[v.index][n.index]=1
 374                                 else:
 375                                         result[v.index][n.index]+=1
 376                 return result
 377
 378         def export(self):
 379                 scene=bpy.data.scenes.active
 380
 381                 obj=scene.objects.active
 382                 if obj.getType()!="Mesh":
 383                         raise Exception, "Can only export Mesh data"
 384
 385                 mesh=Mesh(obj.getData(mesh=True))
 386
 387                 if self.debug:
 388                         ntris=sum([len(f.verts)-2 for f in mesh.faces])
 389                         print "Starting with %d vertices, %d faces (%d triangles) and %d edges"%(len(mesh.verts), len(mesh.faces), ntris, len(mesh.edges))
 390
 391                 mesh.split_smooth(self.split_debug)
 392
 393                 if self.debug:
 394                         print "After smooth splitting %d vertices and %d edges"%(len(mesh.verts), len(mesh.edges))
 395
 396                 mesh.compute_normals()
 397
 398                 if mesh.faceUV:
 399                         mesh.split_uv(self.split_debug)
 400                         if self.debug:
 401                                 print "After UV splitting %d vertices and %d edges"%(len(mesh.verts), len(mesh.edges))
 402
 403                         mesh.compute_uv()
 404                         if self.tbn_vecs:
 405                                 mesh.compute_tbn()
 406
 407                 strips=[]
 408                 if self.use_strips:
 409                         for f in mesh.faces:
 410                                 f.flag=False
 411
 412                         while 1:
 413                                 best=5
 414                                 face=None
 415                                 for f in mesh.faces:
 416                                         if f.flag:
 417                                                 continue
 418                                         score=0
 419                                         for e in f.edges:
 420                                                 other=e.other_face(f)
 421                                                 if other and not other.flag:
 422                                                         score+=1
 423                                         if score>0 and score<best:
 424                                                 face=f
 425                                                 best=score
 426
 427                                 if not face:
 428                                         break
 429
 430                                 strip=mesh.create_strip(face, self.use_degen_tris and sum([len(s) for s in strips])%2, self.strip_debug)
 431                                 if strip:
 432                                         strips.append(strip)
 433
 434                         if self.debug:
 435                                 print "%d strips:"%len(strips)
 436                                 for i in range(len(strips)):
 437                                         print "  %d: %d indices"%(i, len(strips[i]))
 438                                 print "%d loose faces"%len([f for f in mesh.faces if not f.flag])
 439                                 nind=sum([len(s) for s in strips])+sum([len(f.verts) for f in mesh.faces if not f.flag])
 440                                 print "%d indices total"%nind
 441
 442                         if self.use_degen_tris and strips:
 443                                 big_strip=[]
 444                                 for s in strips:
 445                                         if big_strip:
 446                                                 big_strip+=[big_strip[-1], s[0]]
 447                                         big_strip+=s
 448
 449                                 for f in mesh.faces:
 450                                         if not f.flag:
 451                                                 if len(big_strip)%2:
 452                                                         order=(-1, -2, 0, 1)
 453                                                 else:
 454                                                         order=(0, 1, -1, -2)
 455                                                 if big_strip:
 456                                                         big_strip+=[big_strip[-1], f.verts[order[0]]]
 457                                                 big_strip+=[f.verts[i] for i in order[:len(f.verts)]]
 458                                                 f.flag=True
 459
 460                                 strips=[big_strip]
 461
 462                                 if self.debug:
 463                                         nind=len(big_strip)
 464                                         print "Big strip has %d indices"%len(big_strip)
 465
 466                 if self.debug:
 467                         print "%.2f indices per triangle"%(float(nind)/max(ntris, 1))
 468                         print "Locality before optimization: "+" ".join(["%.3f"%self.get_locality(s) for s in strips])
 469
 470                 if self.optimize_locality and self.use_strips and strips:
 471                         followers={}
 472                         for s in strips:
 473                                 followers.update(self.get_followers(s))
 474
 475                         verts2=[]
 476                         vert=strips[0][0]
 477                         while 1:
 478                                 vert.flag=True
 479                                 verts2.append(vert)
 480
 481                                 next=None
 482                                 if vert.index in followers:
 483                                         flw=followers[vert.index]
 484                                         best=0
 485                                         for n in flw:
 486                                                 if flw[n]>best and not mesh.verts[n].flag:
 487                                                         next=mesh.verts[n]
 488                                                         best=flw[n]+0.9/abs(vert.index-n)
 489
 490                                 if not next:
 491                                         for v in mesh.verts:
 492                                                 if not v.flag:
 493                                                         next=v
 494                                                         break
 495                                         if not next:
 496                                                 break
 497
 498                                 vert=next
 499
 500                         mesh.verts=verts2
 501
 502                         for i in range(len(mesh.verts)):
 503                                 mesh.verts[i].index=i
 504
 505                         if self.debug:
 506                                 print "Locality after optimization: "+" ".join(["%.3f"%self.get_locality(s) for s in strips])
 507
 508                 self.out_file.write("vertices NORMAL3")
 509                 if mesh.faceUV:
 510                         self.out_file.write("_TEXCOORD2")
 511                         if self.tbn_vecs:
 512                                 self.out_file.write("_ATTRIB33_ATTRIB34")
 513                 self.out_file.write("_VERTEX3\n{\n")
 514                 norm=None
 515                 uv=None
 516                 tan=None
 517                 bino=None
 518                 for v in mesh.verts:
 519                         if v.no!=norm:
 520                                 self.out_file.write("\tnormal3 %f %f %f;\n"%tuple(v.no))
 521                                 norm=v.no
 522                         if v.uv!=uv:
 523                                 self.out_file.write("\ttexcoord2 %f %f;\n"%tuple(v.uv))
 524                                 uv=v.uv
 525                         if v.tan!=tan:
 526                                 self.out_file.write("\tattrib3 3 %f %f %f;\n"%tuple(v.tan))
 527                                 tan=v.tan
 528                         if v.bino!=bino:
 529                                 self.out_file.write("\tattrib3 4 %f %f %f;\n"%tuple(v.bino))
 530                                 bino=v.bino
 531                         self.out_file.write("\tvertex3 %f %f %f;\n"%tuple(v.co))
 532                 self.out_file.write("};\n")
 533                 for s in strips:
 534                         self.out_file.write("batch TRIANGLE_STRIP\n{\n\tindices")
 535                         n=0
 536                         for v in s:
 537                                 self.out_file.write(" %u"%v.index)
 538                                 n+=1;
 539                                 if n%32==0:
 540                                         self.out_file.write(";\n\tindices")
 541                         self.out_file.write(";\n};\n")
 542
 543                 first=True
 544                 for f in mesh.faces:
 545                         if not f.flag:
 546                                 if first:
 547                                         self.out_file.write("batch TRIANGLES\n{\n")
 548                                         first=False
 549                                 for i in range(2, len(f.verts)):
 550                                         self.out_file.write("\tindices %u %u %u;\n"%(f.verts[0].index, f.verts[i-1].index, f.verts[i].index))
 551                 if not first:
 552                         self.out_file.write("};\n")
 553
 554                 if self.export_lines and mesh.lines:
 555                         self.out_file.write("batch LINES\n{\n")
 556                         for l in mesh.lines:
 557                                 self.out_file.write("\tindices %u %u;\n"%(l.verts[0].index, l.verts[1].index))
 558                         self.out_file.write("};\n")
 559
 560
 561 class FrontEnd:
 562         def __init__(self):
 563                 self.config=Blender.Registry.GetKey('mspgl_export', True) or {}
 564                 self.temp_config=Blender.Registry.GetKey('mspgl_export_temp') or {}
 565
 566         def run(self):
 567                 self.use_strips=Blender.Draw.Create(self.config.get('use_strips', True))
 568                 self.use_degen_tris=Blender.Draw.Create(self.config.get('use_degen_tris', True))
 569                 self.optimize_locality=Blender.Draw.Create(self.config.get('optimize_locality', True))
 570                 self.export_lines=Blender.Draw.Create(self.config.get('export_lines', False))
 571                 self.tbn_vecs=Blender.Draw.Create(self.config.get('tbn_vecs', False))
 572                 self.debug=Blender.Draw.Create(self.config.get('debug', False))
 573                 self.strip_debug=Blender.Draw.Create(self.config.get('strip_debug', False))
 574                 self.split_debug=Blender.Draw.Create(self.config.get('split_debug', False))
 575                 ret=Blender.Draw.PupBlock("Export MSP GL mesh",
 576                         [("Use strips", self.use_strips, "Generage OpenGL triangle strips"),
 577                                 ("Use degen tris", self.use_degen_tris, "Use degenerate triangles to combine triangle strips"),
 578                                 ("Optimize locality", self.optimize_locality),
 579                                 ("Export lines", self.export_lines, "Export lone edges as lines"),
 580                                 ("Compute T/B vecs", self.tbn_vecs, "Compute tangent/binormal vectors for bumpmapping"),
 581                                 ("Debugging options"),
 582                                 ("Debug", self.debug),
 583                                 ("Debug strips", self.strip_debug),
 584                                 ("Debug splitting", self.split_debug)])
 585                 if ret:
 586                         dirname=self.temp_config.get("dirname", Blender.sys.dirname(Blender.Get("filename")))
 587                         obj=bpy.data.scenes.active.objects.active
 588                         Blender.Window.FileSelector(self.export, "Export MSP GL mesh", "%s/%s.mesh"%(dirname, obj.name))
 589
 590         def draw(self):
 591                 pass
 592
 593         def export(self, fn):
 594                 self.config['use_strips']=self.use_strips.val
 595                 self.config['use_degen_tris']=self.use_degen_tris.val
 596                 self.config['optimize_locality']=self.optimize_locality.val
 597                 self.config['export_lines']=self.export_lines.val
 598                 self.config['tbn_vecs']=self.tbn_vecs.val
 599                 self.config['debug']=self.debug.val
 600                 self.config['strip_debug']=self.strip_debug.val
 601                 self.config['split_debug']=self.split_debug.val
 602                 Blender.Registry.SetKey('mspgl_export', self.config, True)
 603
 604                 import os
 605                 self.temp_config["dirname"]=os.path.dirname(fn)
 606                 Blender.Registry.SetKey('mspgl_export_temp', self.temp_config)
 607
 608                 exp=Exporter(fn)
 609                 exp.use_strips=self.use_strips.val
 610                 exp.use_degen_tris=self.use_degen_tris.val
 611                 exp.optimize_locality=self.optimize_locality.val
 612                 exp.export_lines=self.export_lines.val
 613                 exp.tbn_vecs=self.tbn_vecs.val
 614                 exp.debug=self.debug.val
 615                 exp.strip_debug=self.strip_debug.val
 616                 exp.split_debug=self.split_debug.val
 617                 exp.export()
 618
 619
 620 if __name__=="__main__":
 621         fe=FrontEnd()
 622         fe.run()