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, *vt):
 105                 flags = [(v in vt) for v in self.verts]
 106                 l = len(self.verts)
 107                 for i in range(l):
 108                         if flags[i] and not flags[(i+l-1)%l]:
 109                                 return self.verts[i:]+self.verts[:i]
 110
 111         def get_edge(self, v1, v2):
 112                 key = make_edge_key(v1.index, v2.index)
 113                 for e in self.edges:
 114                         if e.key==key:
 115                                 return e
 116                 raise KeyError, "No edge %s"%(key,)
 117
 118
 119 class Line:
 120         def __init__(self, e):
 121                 self.edge = e
 122                 self.verts = [e.v1, e.v2]
 123                 self.flag = False
 124
 125         def __str__(self):
 126                 return "<Line (%d %d)>"%(self.verts[0].index, self.verts[1].index)
 127
 128         __repr__ = __str__
 129
 130
 131 class Mesh:
 132         def __init__(self, m):
 133                 self._mesh = m
 134                 self.verts = [Vertex(v) for v in m.verts]
 135                 self.faces = [Face(f) for f in m.faces]
 136
 137                 for f in self.faces:
 138                         for i in range(len(f.verts)):
 139                                 f.verts[i] = self.verts[f.verts[i].index]
 140                                 f.verts[i].faces.append(f)
 141
 142                 self.edges = dict([(e.key, Edge(e)) for e in m.edges])
 143                 for f in self.faces:
 144                         for k in f.edge_keys:
 145                                 e = self.edges[k]
 146                                 e.faces.append(self.faces[f.index])
 147                                 f.edges.append(e)
 148
 149                 self.lines = [Line(e) for e in self.edges.itervalues() if not e.faces]
 150
 151                 if m.mode&Blender.Mesh.Modes.AUTOSMOOTH:
 152                         smooth_limit = math.cos(m.degr*math.pi/180)
 153                 else:
 154                         smooth_limit = -1
 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, max_len, 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"%([v.index for v in face.verts], (edge.v1.index, edge.v2.index))
 305
 306                 verts = face.pivot_vertices(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                         if debug:
 314                                 print "  Adding %s"%face
 315
 316                         verts = face.pivot_vertices(*result[-2:])
 317                         k = len(result)%2
 318
 319                         face.flag = True
 320                         if len(verts)==4 and not k:
 321                                 result.append(verts[3])
 322                         result.append(verts[2])
 323                         if len(verts)==4 and k:
 324                                 result.append(verts[3])
 325
 326                         if len(result)>=max_len:
 327                                 if debug:
 328                                         print "  Max length exceeded"
 329                                 break
 330
 331                         edge = face.get_edge(*result[-2:])
 332
 333                         if debug:
 334                                 print "  Next edge is %s"%(edge.key, )
 335
 336                         next = edge.other_face(face)
 337                         if not next or next.flag:
 338                                 break
 339                         face = next
 340
 341                 if debug:
 342                         print "  %s"%[v.index for v in result]
 343
 344                 return result
 345
 346
 347 class VertexCache:
 348         def __init__(self, size):
 349                 self.size = size
 350                 self.slots = [-1]*self.size
 351
 352         def fetch(self, v):
 353                 hit = v.index in self.slots
 354                 if hit:
 355                         self.slots.remove(v.index)
 356                 self.slots.append(v.index)
 357                 if not hit:
 358                         del self.slots[0]
 359                 return hit
 360
 361         def fetch_strip(self, strip):
 362                 hits = 0
 363                 for v in strip:
 364                         if self.fetch(v):
 365                                 hits += 1
 366                 return hits
 367
 368         def test_strip(self, strip):
 369                 hits = 0
 370                 for i in range(len(strip)):
 371                         if i>=self.size:
 372                                 break
 373                         if strip[i].index in self.slots[i:]:
 374                                 hits += 1
 375                 return hits
 376
 377
 378 class Exporter:
 379         def __init__(self, fn):
 380                 self.filename = fn
 381                 if fn==None:
 382                         self.out_file = sys.stdout
 383                 else:
 384                         self.out_file = file(fn, "w")
 385                 self.use_strips = True
 386                 self.use_degen_tris = True
 387                 self.max_strip_len = 1024
 388                 self.optimize_cache = False
 389                 self.cache_size = 64
 390                 self.export_lines = True
 391                 self.tbn_vecs = False
 392                 self.debug = False
 393                 self.strip_debug = False
 394                 self.split_debug = False
 395
 396         def stripify(self, mesh):
 397                 for f in mesh.faces:
 398                         f.flag = False
 399
 400                 strips = []
 401
 402                 while 1:
 403                         best = 5
 404                         face = None
 405                         for f in mesh.faces:
 406                                 if f.flag:
 407                                         continue
 408                                 score = 0
 409                                 for e in f.edges:
 410                                         other = e.other_face(f)
 411                                         if other and not other.flag:
 412                                                 score += 1
 413                                 if score>0 and score<best:
 414                                         face = f
 415                                         best = score
 416
 417                         if not face:
 418                                 break
 419
 420                         strip = mesh.create_strip(face, self.max_strip_len, self.strip_debug)
 421                         if strip:
 422                                 strips.append(strip)
 423
 424                 loose = [f for f in mesh.faces if not f.flag]
 425
 426                 if self.debug:
 427                         print "%d strips:"%len(strips)
 428                         for i in range(len(strips)):
 429                                 print "  %d: %d indices"%(i, len(strips[i]))
 430                         print "%d loose faces"%len([f for f in mesh.faces if not f.flag])
 431                         nind = sum([len(s) for s in strips])+sum([len(f.verts) for f in loose])
 432                         print "%d indices total"%nind
 433
 434                 if self.use_degen_tris and strips:
 435                         big_strip = []
 436
 437                         cache = None
 438                         total_hits = 0
 439                         if self.optimize_cache:
 440                                 cache = VertexCache(self.cache_size)
 441
 442                         while strips:
 443                                 best = 0
 444                                 if cache:
 445                                         best_hits = 0
 446                                         for i in range(len(strips)):
 447                                                 hits = cache.test_strip(strips[i])
 448                                                 if hits>best_hits:
 449                                                         best = i
 450                                                         best_hits = hits
 451
 452                                 s = strips[best]
 453
 454                                 if big_strip:
 455                                         glue = [big_strip[-1], s[0]]
 456                                         if len(big_strip)%2:
 457                                                 glue += [s[0]]
 458
 459                                         big_strip += glue
 460                                         if cache:
 461                                                 total_hits += cache.fetch_strip(glue)
 462
 463                                 big_strip += s
 464                                 if cache:
 465                                         total_hits += cache.fetch_strip(s)
 466
 467                                 del strips[best]
 468
 469                         for f in loose:
 470                                 if len(big_strip)%2:
 471                                         order = (-1, -2, 0, 1)
 472                                 else:
 473                                         order = (0, 1, -1, -2)
 474                                 verts = [f.verts[i] for i in order[:len(f.verts)]]
 475                                 if big_strip:
 476                                         glue = [big_strip[-1], verts[0]]
 477                                         big_strip += glue
 478                                         if cache:
 479                                                 total_hits += cache.fetch_strip(glue)
 480                                 big_strip += verts
 481                                 if cache:
 482                                         total_hits += cache.fetch_strip(verts)
 483
 484                         strips = [big_strip]
 485                         loose = []
 486
 487                         if self.debug:
 488                                 nind = len(big_strip)
 489                                 print "Big strip has %d indices"%nind
 490                                 if self.optimize_cache:
 491                                         print "%d cache hits"%total_hits
 492
 493                 if self.debug:
 494                         ntris = sum([len(f.verts)-2 for f in mesh.faces])
 495                         print "%.2f indices per triangle"%(float(nind)/max(ntris, 1))
 496
 497                 return strips, loose
 498
 499         def export(self):
 500                 scene = bpy.data.scenes.active
 501
 502                 obj = scene.objects.active
 503                 if obj.getType()!="Mesh":
 504                         raise Exception, "Can only export Mesh data"
 505
 506                 mesh = Blender.Mesh.New("export_tmp")
 507                 mesh.getFromObject(obj)
 508                 mesh = Mesh(mesh)
 509
 510                 if self.debug:
 511                         ntris = sum([len(f.verts)-2 for f in mesh.faces])
 512                         print "Starting with %d vertices, %d faces (%d triangles) and %d edges"%(len(mesh.verts), len(mesh.faces), ntris, len(mesh.edges))
 513
 514                 mesh.split_smooth(self.split_debug)
 515
 516                 if self.debug:
 517                         print "After smooth splitting %d vertices and %d edges"%(len(mesh.verts), len(mesh.edges))
 518
 519                 mesh.compute_normals()
 520
 521                 if mesh.faceUV:
 522                         mesh.split_uv(self.split_debug)
 523                         if self.debug:
 524                                 print "After UV splitting %d vertices and %d edges"%(len(mesh.verts), len(mesh.edges))
 525
 526                         mesh.compute_uv()
 527                         if self.tbn_vecs:
 528                                 mesh.compute_tbn()
 529
 530                 strips = []
 531                 if self.use_strips:
 532                         strips, loose = self.stripify(mesh)
 533
 534                 self.out_file.write("vertices NORMAL3")
 535                 if mesh.faceUV:
 536                         self.out_file.write("_TEXCOORD2")
 537                         if self.tbn_vecs:
 538                                 self.out_file.write("_ATTRIB33_ATTRIB34")
 539                 self.out_file.write("_VERTEX3\n{\n")
 540                 norm = None
 541                 uv = None
 542                 tan = None
 543                 bino = None
 544                 for v in mesh.verts:
 545                         if v.no!=norm:
 546                                 self.out_file.write("\tnormal3 %f %f %f;\n"%tuple(v.no))
 547                                 norm = v.no
 548                         if v.uv!=uv:
 549                                 self.out_file.write("\ttexcoord2 %f %f;\n"%tuple(v.uv))
 550                                 uv = v.uv
 551                         if v.tan!=tan:
 552                                 self.out_file.write("\tattrib3 3 %f %f %f;\n"%tuple(v.tan))
 553                                 tan = v.tan
 554                         if v.bino!=bino:
 555                                 self.out_file.write("\tattrib3 4 %f %f %f;\n"%tuple(v.bino))
 556                                 bino = v.bino
 557                         self.out_file.write("\tvertex3 %f %f %f;\n"%tuple(v.co))
 558                 self.out_file.write("};\n")
 559                 for s in strips:
 560                         self.out_file.write("batch TRIANGLE_STRIP\n{\n\tindices")
 561                         n = 0
 562                         for v in s:
 563                                 self.out_file.write(" %u"%v.index)
 564                                 n += 1;
 565                                 if n%32==0:
 566                                         self.out_file.write(";\n\tindices")
 567                         self.out_file.write(";\n};\n")
 568
 569                 first = True
 570                 for f in loose:
 571                         if first:
 572                                 self.out_file.write("batch TRIANGLES\n{\n")
 573                                 first = False
 574                         for i in range(2, len(f.verts)):
 575                                 self.out_file.write("\tindices %u %u %u;\n"%(f.verts[0].index, f.verts[i-1].index, f.verts[i].index))
 576                 if not first:
 577                         self.out_file.write("};\n")
 578
 579                 if self.export_lines and mesh.lines:
 580                         self.out_file.write("batch LINES\n{\n")
 581                         for l in mesh.lines:
 582                                 self.out_file.write("\tindices %u %u;\n"%(l.verts[0].index, l.verts[1].index))
 583                         self.out_file.write("};\n")
 584
 585
 586 class FrontEnd:
 587         def __init__(self):
 588                 self.config = Blender.Registry.GetKey('mspgl_export', True) or {}
 589                 self.temp_config = Blender.Registry.GetKey('mspgl_export_temp') or {}
 590
 591         def run(self):
 592                 self.use_strips = Blender.Draw.Create(self.config.get('use_strips', True))
 593                 self.use_degen_tris = Blender.Draw.Create(self.config.get('use_degen_tris', True))
 594                 self.max_strip_len = Blender.Draw.Create(self.config.get('max_strip_len', 1024))
 595                 self.optimize_cache = Blender.Draw.Create(self.config.get('optimize_cache', False))
 596                 self.cache_size = Blender.Draw.Create(self.config.get('cache_size', 64))
 597                 self.export_lines = Blender.Draw.Create(self.config.get('export_lines', False))
 598                 self.tbn_vecs = Blender.Draw.Create(self.config.get('tbn_vecs', False))
 599                 self.debug = Blender.Draw.Create(self.config.get('debug', False))
 600                 self.strip_debug = Blender.Draw.Create(self.config.get('strip_debug', False))
 601                 self.split_debug = Blender.Draw.Create(self.config.get('split_debug', False))
 602                 ret = Blender.Draw.PupBlock("Export MSP GL mesh",
 603                         [("Use strips", self.use_strips, "Generage OpenGL triangle strips"),
 604                                 ("Use degen tris", self.use_degen_tris, "Use degenerate triangles to combine triangle strips"),
 605                                 ("Max strip len", self.max_strip_len, 4, 16384, "Maximum length of a triangle strip"),
 606                                 ("Optimize cache", self.optimize_cache, "Optimize for vertex cache"),
 607                                 ("Cache size", self.cache_size, 8, 1024, "Cache size to optimize for"),
 608                                 ("Export lines", self.export_lines, "Export lone edges as lines"),
 609                                 ("Compute T/B vecs", self.tbn_vecs, "Compute tangent/binormal vectors for bumpmapping"),
 610                                 ("Debugging options"),
 611                                 ("Debug", self.debug),
 612                                 ("Debug strips", self.strip_debug),
 613                                 ("Debug splitting", self.split_debug)])
 614                 if ret:
 615                         dirname = self.temp_config.get("dirname", Blender.sys.dirname(Blender.Get("filename")))
 616                         obj = bpy.data.scenes.active.objects.active
 617                         Blender.Window.FileSelector(self.export, "Export MSP GL mesh", "%s/%s.mesh"%(dirname, obj.name))
 618
 619         def draw(self):
 620                 pass
 621
 622         def export(self, fn):
 623                 self.config['use_strips'] = self.use_strips.val
 624                 self.config['use_degen_tris'] = self.use_degen_tris.val
 625                 self.config['max_strip_len'] = self.max_strip_len.val
 626                 self.config['optimize_cache'] = self.optimize_cache.val
 627                 self.config['cache_size'] = self.cache_size.val
 628                 self.config['export_lines'] = self.export_lines.val
 629                 self.config['tbn_vecs'] = self.tbn_vecs.val
 630                 self.config['debug'] = self.debug.val
 631                 self.config['strip_debug'] = self.strip_debug.val
 632                 self.config['split_debug'] = self.split_debug.val
 633                 Blender.Registry.SetKey('mspgl_export', self.config, True)
 634
 635                 import os
 636                 self.temp_config["dirname"] = os.path.dirname(fn)
 637                 Blender.Registry.SetKey('mspgl_export_temp', self.temp_config)
 638
 639                 exp = Exporter(fn)
 640                 exp.use_strips = self.use_strips.val
 641                 exp.use_degen_tris = self.use_degen_tris.val
 642                 exp.max_strip_len = self.max_strip_len.val
 643                 exp.optimize_cache = self.optimize_cache.val
 644                 exp.cache_size = self.cache_size.val
 645                 exp.export_lines = self.export_lines.val
 646                 exp.tbn_vecs = self.tbn_vecs.val
 647                 exp.debug = self.debug.val
 648                 exp.strip_debug = self.strip_debug.val
 649                 exp.split_debug = self.split_debug.val
 650                 exp.export()
 651
 652
 653 if __name__=="__main__":
 654         fe = FrontEnd()
 655         fe.run()