blender/io_mspgl/mesh.py

   1 import bpy
   2 import math
   3 import mathutils
   4
   5 def make_edge_key(i1, i2):
   6         return (min(i1, i2), max(i1, i2))
   7
   8 class Edge:
   9         def __init__(self, edge):
  10                 if edge.__class__==Edge:
  11                         self._edge = edge._edge
  12                         self.vertices = edge.vertices[:]
  13                         self.smooth = edge.smooth
  14                 else:
  15                         self._edge = edge
  16                         self.smooth = False
  17                 self.key = edge.key
  18                 self.faces = []
  19
  20         def __getattr__(self, attr):
  21                 return getattr(self._edge, attr)
  22
  23         def check_smooth(self, limit):
  24                 if len(self.faces)!=2:
  25                         return
  26
  27                 d = self.faces[0].normal.dot(self.faces[1].normal)
  28                 self.smooth = ((d>limit and self.faces[0].use_smooth and self.faces[1].use_smooth) or d>0.99995)
  29
  30         def other_face(self, f):
  31                 if f.index==self.faces[0].index:
  32                         if len(self.faces)>=2:
  33                                 return self.faces[1]
  34                         else:
  35                                 return None
  36                 else:
  37                         return self.faces[0]
  38
  39         def other_vertex(self, v):
  40                 if v.index==self.vertices[0].index:
  41                         return self.vertices[1]
  42                 else:
  43                         return self.vertices[0]
  44
  45
  46 class Vertex:
  47         def __init__(self, vertex):
  48                 if vertex.__class__==Vertex:
  49                         self._vertex = vertex._vertex
  50                         self.uvs = vertex.uvs[:]
  51                         self.tan = vertex.tan
  52                         self.bino = vertex.bino
  53                 else:
  54                         self._vertex = vertex
  55                         self.uvs = []
  56                         self.tan = None
  57                         self.bino = None
  58                 self.index = vertex.index
  59                 self.co = vertex.co
  60                 self.normal = vertex.normal
  61                 self.flag = False
  62                 self.edges = []
  63                 self.faces = []
  64                 self.groups = vertex.groups[:]
  65
  66         def __getattr__(self, attr):
  67                 return getattr(self._vertex, attr)
  68
  69         def __cmp__(self, other):
  70                 if other is None:
  71                         return 1
  72                 return cmp(self.index, other.index)
  73
  74
  75 class VertexGroup:
  76         def __init__(self, group):
  77                 self._group = group
  78                 self.group = group.group
  79                 self.weight = group.weight
  80
  81         def __getattr__(self, attr):
  82                 return getattr(self._group, attr)
  83
  84
  85 class Face:
  86         def __init__(self, face):
  87                 self._face = face
  88                 self.index = face.index
  89                 self.edges = []
  90                 self.vertices = face.vertices[:]
  91                 self.uvs = []
  92                 self.flag = False
  93
  94         def __getattr__(self, attr):
  95                 return getattr(self._face, attr)
  96
  97         def __cmp__(self, other):
  98                 if other is None:
  99                         return 1
 100                 return cmp(self.index, other.index)
 101
 102         def pivot_vertex(self, v):
 103                 n = self.vertices.index(v)
 104                 return [(n+i)%len(self.vertices) for i in range(len(self.vertices))]
 105
 106         def pivot_vertices(self, *vt):
 107                 flags = [(v in vt) for v in self.vertices]
 108                 l = len(self.vertices)
 109                 for i in range(l):
 110                         if flags[i] and not flags[(i+l-1)%l]:
 111                                 return self.vertices[i:]+self.vertices[:i]
 112
 113         def get_edge(self, v1, v2):
 114                 key = make_edge_key(v1.index, v2.index)
 115                 for e in self.edges:
 116                         if e.key==key:
 117                                 return e
 118                 raise KeyError("No edge %s"%(key,))
 119
 120         def other_edge(self, e, v):
 121                 for d in self.edges:
 122                         if d!=e and v in d.vertices:
 123                                 return d
 124
 125         def get_neighbors(self):
 126                 neighbors = [e.other_face(self) for e in self.edges]
 127                 return list(filter(bool, neighbors))
 128
 129
 130 class Line:
 131         def __init__(self, e):
 132                 self.edge = e
 133                 self.vertices = e.vertices[:]
 134                 self.flag = False
 135
 136
 137 class UvLayer:
 138         def __init__(self, arg):
 139                 if type(arg)==str:
 140                         self._layer = None
 141                         self.name = arg
 142                 else:
 143                         self._layer = arg
 144                         self.name = arg.name
 145                         self.uvs = [d.uv for d in self.data]
 146
 147                 self.unit = None
 148                 self.hidden = False
 149
 150                 dot = self.name.find('.')
 151                 if dot>=0:
 152                         ext = self.name[dot:]
 153                         if ext.startswith(".unit") and ext[5:].isdigit():
 154                                 self.unit = int(ext[5:])
 155                         elif ext==".hidden":
 156                                 self.hidden = True
 157
 158         def __getattr__(self, attr):
 159                 return getattr(self._layer, attr)
 160
 161
 162 class Mesh:
 163         def __init__(self, mesh):
 164                 self._mesh = mesh
 165
 166                 self.winding_test = mesh.winding_test
 167                 self.tbn_vecs = mesh.tbn_vecs
 168                 self.vertex_groups = mesh.vertex_groups
 169
 170                 # Clone basic data
 171                 self.vertices = [Vertex(v) for v in self.vertices]
 172                 for v in self.vertices:
 173                         v.groups = [VertexGroup(g) for g in v.groups]
 174
 175                 self.faces = [Face(f) for f in self.polygons]
 176                 self.edges = [Edge(e) for e in self.edges]
 177                 self.loops = self.loops[:]
 178                 self.materials = self.materials[:]
 179
 180                 # Clone only the desired UV layers
 181                 if self.use_uv=='NONE' or not self.uv_layers:
 182                         self.uv_layers = []
 183                 else:
 184                         self.uv_layers = [UvLayer(u) for u in self.uv_layers]
 185                         self.uv_layers = sorted([u for u in self.uv_layers if not u.hidden], key=(lambda u: (u.unit or 1000, u.name)))
 186
 187                         if self.use_uv=='UNIT0':
 188                                 self.uv_layers = [self.uv_layers[0]]
 189
 190                         # Assign texture unit numbers to UV layers that lack one
 191                         next_unit = max((u.unit+1 for u in self.uv_layers if u.unit is not None), default=0)
 192                         for u in self.uv_layers:
 193                                 if not u.unit:
 194                                         u.unit = next_unit
 195                                         next_unit += 1
 196
 197                 # Rewrite links between elements to point to cloned data, or create links
 198                 # where they don't exist
 199                 edge_map = {e.key: e for e in self.edges}
 200                 for f in self.faces:
 201                         if len(f.vertices)>4:
 202                                 raise ValueError("Ngons are not supported")
 203
 204                         f.vertices = [self.vertices[i] for i in f.vertices]
 205                         for v in f.vertices:
 206                                 v.faces.append(f)
 207
 208                         for k in f.edge_keys:
 209                                 e = edge_map[k]
 210                                 e.faces.append(f)
 211                                 f.edges.append(e)
 212
 213                 for e in self.edges:
 214                         e.vertices = [self.vertices[i] for i in e.vertices]
 215                         for v in e.vertices:
 216                                 v.edges.append(e)
 217
 218                 # Store loose edges as lines
 219                 if self.use_lines:
 220                         self.lines = [Line(e) for e in self.edges if not e.faces]
 221                 else:
 222                         self.lines = []
 223
 224         def __getattr__(self, attr):
 225                 return getattr(self._mesh, attr)
 226
 227         def transform(self, matrix):
 228                 for v in self.vertices:
 229                         v.co = matrix*v.co
 230
 231         def splice(self, other):
 232                 if len(self.uv_layers)!=len(other.uv_layers):
 233                         raise ValueError("Meshes have incompatible UV layers")
 234                 for i, u in enumerate(self.uv_layers):
 235                         if u.name!=other.uv_layers[i].name:
 236                                 raise ValueError("Meshes have incompatible UV layers")
 237
 238                 # Merge materials and form a lookup from source material indices to the
 239                 # merged material list
 240                 material_map = []
 241                 for m in other.materials:
 242                         if m in self.materials:
 243                                 material_map.append(self.materials.index(m))
 244                         else:
 245                                 material_map.append(len(self.materials))
 246                                 self.materials.append(m)
 247
 248                 # Append data and adjust indices where necessary.  Since the data is
 249                 # spliced from the source mesh, rebuilding references is not necessary.
 250                 for i, u in enumerate(self.uv_layers):
 251                         u.uvs += other.uv_layers[i].uvs
 252
 253                 offset = len(self.vertices)
 254                 self.vertices += other.vertices
 255                 for v in self.vertices[offset:]:
 256                         v.index += offset
 257
 258                 loop_offset = len(self.loops)
 259                 self.loops += other.loops
 260
 261                 offset = len(self.faces)
 262                 self.faces += other.faces
 263                 for f in self.faces[offset:]:
 264                         f.index += offset
 265                         f.loop_start += loop_offset
 266                         f.loop_indices = range(f.loop_start, f.loop_start+f.loop_total)
 267                         if other.materials:
 268                                 f.material_index = material_map[f.material_index]
 269
 270                 offset = len(self.edges)
 271                 self.edges += other.edges
 272                 for e in self.edges[offset:]:
 273                         e.index += offset
 274                         e.key = make_edge_key(e.vertices[0].index, e.vertices[1].index)
 275
 276                 self.lines += other.lines
 277
 278         def prepare_smoothing(self, progress):
 279                 smooth_limit = -1
 280                 if self.smoothing=='NONE':
 281                         for f in self.faces:
 282                                 f.use_smooth = False
 283
 284                         smooth_limit = 1
 285                 elif self.use_auto_smooth:
 286                         smooth_limit = math.cos(self.auto_smooth_angle)
 287
 288                 for e in self.edges:
 289                         e.check_smooth(smooth_limit)
 290
 291                 progress.push_task("Sharp edges", 0.0, 0.7)
 292                 self.split_vertices(self.find_smooth_group, progress)
 293
 294                 if self.smoothing!='BLENDER':
 295                         progress.set_task("Updating normals", 0.7, 1.0)
 296                         self.compute_normals(progress)
 297
 298                 progress.pop_task()
 299
 300         def prepare_vertex_groups(self, obj):
 301                 for v in self.vertices:
 302                         if v.groups:
 303                                 weight_sum = sum(g.weight for g in v.groups)
 304                                 v.groups = sorted(v.groups, key=(lambda g: g.weight), reverse=True)[:self.max_groups_per_vertex]
 305                                 weight_scale = weight_sum/sum(g.weight for g in v.groups)
 306                                 for g in v.groups:
 307                                         g.weight *= weight_scale
 308
 309                 if obj.parent and obj.parent.type=="ARMATURE":
 310                         armature = obj.parent.data
 311                         bone_indices = {b.name: i for i, b in enumerate(armature.bones)}
 312                         group_index_map = {i: i for i in range(len(obj.vertex_groups))}
 313                         for g in first_obj.vertex_groups:
 314                                 if g.name in bone_indices:
 315                                         group_index_map[g.index] = bone_indices[g.name]
 316
 317                         for v in self.vertices:
 318                                 for g in v.groups:
 319                                         g.group = group_index_map[g.group]
 320
 321         def prepare_uv(self, obj, progress):
 322                 if obj.material_tex and self.use_uv!='NONE':
 323                         layer = UvLayer("material_tex")
 324
 325                         if self.use_uv=='UNIT0':
 326                                 self.uv_layers = [layer]
 327                                 layer.unit = 0
 328                         else:
 329                                 self.uv_layers.append(layer)
 330                                 layer.unit = max((u.unit+1 for u in self.uv_layers if u.unit is not None), default=0)
 331
 332                         layer.uvs = [None]*len(self.loops)
 333                         for f in self.faces:
 334                                 uv = mathutils.Vector(((f.material_index+0.5)/len(self.materials), 0.5))
 335                                 for i in f.loop_indices:
 336                                         layer.uvs[i] = uv
 337
 338                 # Form a list of UV layers referenced by materials with the array atlas
 339                 # property set
 340                 array_uv_layers = [t.uv_layer for m in self.materials if m.array_atlas for t in m.texture_slots if t and t.texture_coords=='UV']
 341                 array_uv_layers = [u for u in self.uv_layers if u.name in array_uv_layers]
 342
 343                 if array_uv_layers:
 344                         for f in self.faces:
 345                                 layer = 0
 346                                 if f.material_index<len(self.materials):
 347                                         mat = self.materials[f.material_index]
 348                                         if mat and mat.array_atlas:
 349                                                 layer = mat.array_layer
 350
 351                                 for l in array_uv_layers:
 352                                         for i in f.loop_indices:
 353                                                 l.uvs[i] = mathutils.Vector((*l.uvs[i], layer))
 354
 355                 # Copy UVs from layers to faces
 356                 for f in self.faces:
 357                         for u in self.uv_layers:
 358                                 f.uvs.append([u.uvs[i] for i in f.loop_indices])
 359
 360                 prog_count = len(self.uv_layers)
 361                 prog_step = 0
 362
 363                 # Split by the UV layer used for TBN vectors first so connectivity
 364                 # remains intact for TBN vector computation
 365                 tbn_layer_index = -1
 366                 if self.tbn_vecs:
 367                         uv_names = [u.name for u in self.uv_layers]
 368                         if self.tbn_uvtex in uv_names:
 369                                 prog_count += 1
 370                                 tbn_layer_index = uv_names.index(self.tbn_uvtex)
 371                                 progress.push_task_slice("Computing TBN", 0, prog_count)
 372                                 self.split_vertices(self.find_uv_group, progress, tbn_layer_index)
 373                                 progress.set_task_slice(self.tbn_uvtex, 1, prog_count)
 374                                 self.compute_tbn(tbn_layer_index, progress)
 375                                 progress.pop_task()
 376                                 prog_step = 2
 377
 378                 # Split by the remaining UV layers
 379                 for i, u in enumerate(self.uv_layers):
 380                         if i==tbn_layer_index:
 381                                 continue
 382
 383                         progress.push_task_slice(u.name, prog_step, prog_count)
 384                         self.split_vertices(self.find_uv_group, progress, i)
 385                         progress.pop_task()
 386                         prog_step += 1
 387
 388                 # Copy UVs from faces to vertices
 389                 for v in self.vertices:
 390                         if v.faces:
 391                                 # All faces still connected to the vertex have the same UV value
 392                                 f = v.faces[0]
 393                                 i = f.vertices.index(v)
 394                                 v.uvs = [u[i] for u in f.uvs]
 395                         else:
 396                                 v.uvs = [(0.0, 0.0)]*len(self.uv_layers)
 397
 398         def split_vertices(self, find_group_func, progress, *args):
 399                 vertex_count = len(self.vertices)
 400                 for i in range(vertex_count):
 401                         v = self.vertices[i]
 402                         for f in v.faces:
 403                                 f.flag = False
 404
 405                         # Find all groups of faces on this vertex
 406                         groups = []
 407                         for f in v.faces:
 408                                 if not f.flag:
 409                                         groups.append(find_group_func(v, f, *args))
 410
 411                         # Give groups after the first separate copies of the vertex
 412                         for g in groups[1:]:
 413                                 nv = Vertex(v)
 414                                 nv.index = len(self.vertices)
 415                                 self.vertices.append(nv)
 416
 417                                 for e in v.edges:
 418                                         e_faces_in_g = [f for f in e.faces if f in g]
 419                                         if not e_faces_in_g:
 420                                                 continue
 421
 422                                         if len(e_faces_in_g)<len(e.faces):
 423                                                 # Create a copy of an edge at the boundary of the group
 424                                                 ne = Edge(e)
 425                                                 ne.index = len(self.edges)
 426                                                 self.edges.append(ne)
 427
 428                                                 ne.other_vertex(v).edges.append(ne)
 429
 430                                                 for f in e_faces_in_g:
 431                                                         e.faces.remove(f)
 432                                                         f.edges[f.edges.index(e)] = ne
 433                                                         ne.faces.append(f)
 434
 435                                                 e = ne
 436
 437                                         e.vertices[e.vertices.index(v)] = nv
 438                                         nv.edges.append(e)
 439
 440                                         e.key = make_edge_key(e.vertices[0].index, e.vertices[1].index)
 441
 442                                 # Filter out any edges that were removed from the original vertex
 443                                 v.edges = [e for e in v.edges if v in e.vertices]
 444
 445                                 for f in g:
 446                                         v.faces.remove(f)
 447                                         f.vertices[f.vertices.index(v)] = nv
 448                                         nv.faces.append(f)
 449
 450                         progress.set_progress(i/vertex_count)
 451
 452         def find_smooth_group(self, vertex, face):
 453                 face.flag = True
 454
 455                 edges = [e for e in face.edges if vertex in e.vertices]
 456
 457                 group = [face]
 458                 for e in edges:
 459                         f = face
 460                         while e.smooth:
 461                                 f = e.other_face(f)
 462                                 if not f or f.flag:
 463                                         break
 464
 465                                 f.flag = True
 466                                 group.append(f)
 467                                 e = f.other_edge(e, vertex)
 468
 469                 return group
 470
 471         def find_uv_group(self, vertex, face, index):
 472                 uv = face.uvs[index][face.vertices.index(vertex)]
 473                 face.flag = True
 474
 475                 group = [face]
 476                 for f in vertex.faces:
 477                         if not f.flag and f.uvs[index][f.vertices.index(vertex)]==uv:
 478                                 f.flag = True
 479                                 group.append(f)
 480
 481                 return group
 482
 483         def compute_normals(self, progress):
 484                 for i, v in enumerate(self.vertices):
 485                         v.normal = mathutils.Vector()
 486                         for f in v.faces:
 487                                 fv = f.pivot_vertices(v)
 488                                 edge1 = fv[1].co-fv[0].co
 489                                 edge2 = fv[-1].co-fv[0].co
 490                                 if edge1.length and edge2.length:
 491                                         # Use the angle between edges as a weighting factor.  This gives
 492                                         # more consistent normals on bends with an inequal number of
 493                                         # faces on each side.
 494                                         v.normal += f.normal*edge1.angle(edge2)
 495
 496                         if v.normal.length:
 497                                 v.normal.normalize()
 498                         else:
 499                                 v.normal = mathutils.Vector((0, 0, 1))
 500
 501                         progress.set_progress(i/len(self.vertices))
 502
 503         def compute_tbn(self, index, progress):
 504                 # This function is called at an early stage during UV preparation when
 505                 # face UVs are not available yet
 506                 layer_uvs = self.uv_layers[index].uvs
 507
 508                 for i, v in enumerate(self.vertices):
 509                         v.tan = mathutils.Vector()
 510                         v.bino = mathutils.Vector()
 511                         for f in v.faces:
 512                                 vi = f.pivot_vertex(v)
 513                                 uv0 = layer_uvs[f.loop_indices[vi[0]]]
 514                                 uv1 = layer_uvs[f.loop_indices[vi[1]]]
 515                                 uv2 = layer_uvs[f.loop_indices[vi[-1]]]
 516                                 du1 = uv1[0]-uv0[0]
 517                                 du2 = uv2[0]-uv0[0]
 518                                 dv1 = uv1[1]-uv0[1]
 519                                 dv2 = uv2[1]-uv0[1]
 520                                 edge1 = f.vertices[vi[1]].co-f.vertices[vi[0]].co
 521                                 edge2 = f.vertices[vi[-1]].co-f.vertices[vi[0]].co
 522                                 div = (du1*dv2-du2*dv1)
 523                                 if div:
 524                                         mul = edge1.angle(edge2)/div
 525                                         v.tan += (edge1*dv2-edge2*dv1)*mul
 526                                         v.bino += (edge2*du1-edge1*du2)*mul
 527
 528                         if v.tan.length:
 529                                 v.tan.normalize()
 530                         if v.bino.length:
 531                                 v.bino.normalize()
 532
 533                         progress.set_progress(i/len(self.vertices))
 534
 535         def drop_references(self):
 536                 for v in self.vertices:
 537                         v._vertex = None
 538                         for g in v.groups:
 539                                 g._group = None
 540                 for e in self.edges:
 541                         e._edge = None
 542                 for f in self.faces:
 543                         f._face = None
 544                 for u in self.uv_layers:
 545                         u._layer = None
 546                 self._mesh = None
 547
 548         def create_strip(self, face, max_len):
 549                 # Find an edge with another unused face next to it
 550                 edge = None
 551                 for e in face.edges:
 552                         other = e.other_face(face)
 553                         if other and not other.flag:
 554                                 edge = e
 555                                 break
 556
 557                 if not edge:
 558                         return None
 559
 560                 # Add initial vertices so that we'll complete the edge on the first
 561                 # iteration
 562                 vertices = face.pivot_vertices(*edge.vertices)
 563                 if len(vertices)==3:
 564                         result = [vertices[-1], vertices[0]]
 565                 else:
 566                         result = [vertices[-2], vertices[-1]]
 567
 568                 while 1:
 569                         face.flag = True
 570
 571                         vertices = face.pivot_vertices(*result[-2:])
 572                         k = len(result)%2
 573
 574                         # Quads need special handling because the winding of every other
 575                         # triangle in the strip is reversed
 576                         if len(vertices)==4 and not k:
 577                                 result.append(vertices[3])
 578                         result.append(vertices[2])
 579                         if len(vertices)==4 and k:
 580                                 result.append(vertices[3])
 581
 582                         if len(result)>=max_len:
 583                                 break
 584
 585                         # Hop over the last edge
 586                         edge = face.get_edge(*result[-2:])
 587                         face = edge.other_face(face)
 588                         if not face or face.flag:
 589                                 break
 590
 591                 return result
 592
 593 def create_mesh_from_object(context, obj, progress):
 594         if obj.type!="MESH":
 595                 raise Exception("Object is not a mesh")
 596
 597         progress.push_task("Preparing mesh", 0.0, 0.3)
 598
 599         objs = [(obj, mathutils.Matrix())]
 600         i = 0
 601         while i<len(objs):
 602                 o, m = objs[i]
 603                 i += 1
 604                 for c in o.children:
 605                         if c.type=="MESH" and c.compound:
 606                                 objs.append((c, m*c.matrix_local))
 607
 608         mesh = None
 609         bmeshes = []
 610         for o, m in objs:
 611                 bmesh = o.to_mesh(context.scene, True, "PREVIEW")
 612                 bmeshes.append(bmesh)
 613
 614                 # Object.to_mesh does not copy custom properties
 615                 bmesh.winding_test = o.data.winding_test
 616                 bmesh.smoothing = o.data.smoothing
 617                 bmesh.use_lines = o.data.use_lines
 618                 bmesh.vertex_groups = o.data.vertex_groups
 619                 bmesh.max_groups_per_vertex = o.data.max_groups_per_vertex
 620                 bmesh.use_uv = o.data.use_uv
 621                 bmesh.tbn_vecs = o.data.tbn_vecs
 622                 bmesh.tbn_uvtex = o.data.tbn_uvtex
 623
 624                 me = Mesh(bmesh)
 625                 me.transform(m)
 626
 627                 if mesh:
 628                         mesh.splice(me)
 629                 else:
 630                         mesh = me
 631
 632         progress.set_task("Smoothing", 0.3, 0.6)
 633         mesh.prepare_smoothing(progress)
 634         progress.set_task("Vertex groups", 0.6, 0.7)
 635         mesh.prepare_vertex_groups(obj)
 636         progress.set_task("Preparing UVs", 0.7, 1.0)
 637         mesh.prepare_uv(obj, progress)
 638
 639         # Discard the temporary Blender meshes after making sure there's no
 640         # references to the data
 641         mesh.drop_references()
 642         for m in bmeshes:
 643                 bpy.data.meshes.remove(m)
 644
 645         progress.pop_task()
 646
 647         return mesh