blender/io_mspgl/mesh.py

   1 import math
   2 import mathutils
   3
   4 def make_edge_key(i1, i2):
   5         return (min(i1, i2), max(i1, i2))
   6
   7 class Edge:
   8         def __init__(self, me):
   9                 if me.__class__==Edge:
  10                         self._medge = me._medge
  11                         self.vertices = me.vertices[:]
  12                         self.smooth = me.smooth
  13                 else:
  14                         self._medge = me
  15                         self.smooth = False
  16                 self.faces = []
  17
  18         def __getattr__(self, attr):
  19                 return getattr(self._medge, attr)
  20
  21         def check_smooth(self, limit):
  22                 if len(self.faces)!=2:
  23                         return
  24
  25                 d = self.faces[0].normal.dot(self.faces[1].normal)
  26                 self.smooth = ((d>limit and self.faces[0].use_smooth and self.faces[1].use_smooth) or d>0.99995)
  27
  28         def other_face(self, f):
  29                 if f.index==self.faces[0].index:
  30                         if len(self.faces)>=2:
  31                                 return self.faces[1]
  32                         else:
  33                                 return None
  34                 else:
  35                         return self.faces[0]
  36
  37         def other_vertex(self, v):
  38                 if v.index==self.vertices[0].index:
  39                         return self.vertices[1]
  40                 else:
  41                         return self.vertices[0]
  42
  43
  44 class Vertex:
  45         def __init__(self, mv):
  46                 if mv.__class__==Vertex:
  47                         self._mvert = mv._mvert
  48                         self.normal = mv.normal
  49                         self.uvs = mv.uvs[:]
  50                         self.tan = mv.tan
  51                         self.bino = mv.bino
  52                         self.group_weight_scale = mv.group_weight_scale
  53                 else:
  54                         self._mvert = mv
  55                         self.uvs = []
  56                         self.tan = None
  57                         self.bino = None
  58                         self.group_weight_scale = 1
  59                 self.flag = False
  60                 self.faces = []
  61
  62         def __getattr__(self, attr):
  63                 return getattr(self._mvert, attr)
  64
  65         def __cmp__(self, other):
  66                 if other is None:
  67                         return 1
  68                 return cmp(self.index, other.index)
  69
  70
  71 class Face:
  72         def __init__(self, mf):
  73                 self._mface = mf
  74                 self.edges = []
  75                 self.vertices = mf.vertices[:]
  76                 self.uvs = []
  77                 self.flag = False
  78
  79         def __getattr__(self, attr):
  80                 return getattr(self._mface, attr)
  81
  82         def __cmp__(self, other):
  83                 if other is None:
  84                         return 1
  85                 return cmp(self.index, other.index)
  86
  87         def pivot_vertices(self, *vt):
  88                 flags = [(v in vt) for v in self.vertices]
  89                 l = len(self.vertices)
  90                 for i in range(l):
  91                         if flags[i] and not flags[(i+l-1)%l]:
  92                                 return self.vertices[i:]+self.vertices[:i]
  93
  94         def get_edge(self, v1, v2):
  95                 key = make_edge_key(v1.index, v2.index)
  96                 for e in self.edges:
  97                         if e.key==key:
  98                                 return e
  99                 raise KeyError("No edge %s"%(key,))
 100
 101         def get_neighbors(self):
 102                 neighbors = [e.other_face(self) for e in self.edges]
 103                 return list(filter(bool, neighbors))
 104
 105
 106 class Line:
 107         def __init__(self, e):
 108                 self.edge = e
 109                 self.vertices = e.vertices[:]
 110                 self.flag = False
 111
 112
 113 class UvLayer:
 114         def __init__(self, l, t):
 115                 self._layer = l
 116                 self.uvtex = t
 117                 self.name = self.uvtex.name
 118                 self.unit = None
 119                 self.hidden = False
 120                 dot = self.name.find('.')
 121                 if dot>=0:
 122                         ext = self.name[dot:]
 123                         if ext.startswith(".unit") and ext[5:].isdigit():
 124                                 self.unit = int(ext[5:])
 125                         elif ext==".hidden":
 126                                 self.hidden = True
 127
 128         def __getattr__(self, attr):
 129                 return getattr(self._layer, attr)
 130
 131 class FakeUvLayer:
 132         def __init__(self, n):
 133                 self.uvtex = None
 134                 self.name = n
 135                 self.unit = None
 136                 self.hidden = False
 137
 138 class Mesh:
 139         def __init__(self, m):
 140                 self._mesh = m
 141
 142                 self.vertices = [Vertex(v) for v in self.vertices]
 143                 self.faces = [Face(f) for f in self.polygons]
 144
 145                 self.materials = self.materials[:]
 146
 147                 self.uv_layers = [UvLayer(self.uv_layers[i], self.uv_textures[i]) for i in range(len(self.uv_layers))]
 148                 self.assign_texture_units()
 149
 150                 for f in self.faces:
 151                         f.vertices = [self.vertices[i] for i in f.vertices]
 152                         for v in f.vertices:
 153                                 v.faces.append(f)
 154                         for u in self.uv_layers:
 155                                 f.uvs.append([u.data[f.loop_indices[i]].uv for i in range(len(f.vertices))])
 156
 157                 self.edges = dict([(e.key, Edge(e)) for e in self.edges])
 158                 for f in self.faces:
 159                         for k in f.edge_keys:
 160                                 e = self.edges[k]
 161                                 e.faces.append(self.faces[f.index])
 162                                 f.edges.append(e)
 163
 164                 self.lines = [Line(e) for e in self.edges.values() if not e.faces]
 165
 166                 if self.use_auto_smooth:
 167                         smooth_limit = math.cos(self.auto_smooth_angle)
 168                 else:
 169                         smooth_limit = -1
 170
 171                 for e in self.edges.values():
 172                         e.vertices = [self.vertices[i] for i in e.vertices]
 173                         e.check_smooth(smooth_limit)
 174
 175         def __getattr__(self, attr):
 176                 return getattr(self._mesh, attr)
 177
 178         def splice(self, other):
 179                 material_map = []
 180                 for m in other.materials:
 181                         if m in self.materials:
 182                                 material_map.append(self.materials.index(m))
 183                         else:
 184                                 material_map.append(len(self.materials))
 185                                 self.materials.append(m)
 186
 187                 offset = len(self.vertices)
 188                 for v in other.vertices:
 189                         v.index += offset
 190                         self.vertices.append(v)
 191
 192                 offset = len(self.faces)
 193                 for f in other.faces:
 194                         f.index += offset
 195                         if other.materials:
 196                                 f.material_index = material_map[f.material_index]
 197                         self.faces.append(f)
 198
 199                 for e in other.edges.values():
 200                         e.key = make_edge_key(e.vertices[0].index, e.vertices[1].index)
 201                         self.edges[e.key] = e
 202
 203                 self.lines += other.lines
 204
 205         def flatten_faces(self):
 206                 for f in self.faces:
 207                         f.use_smooth = False
 208
 209                 for e in self.edges.values():
 210                         e.check_smooth(1)
 211
 212         def assign_texture_units(self):
 213                 # Assign texture units for any non-hidden UV layers that lack one
 214                 units = [u.unit for u in self.uv_layers if u.unit is not None]
 215                 if units:
 216                         free_unit = max(units)+1
 217                 else:
 218                         free_unit = 0
 219                 for u in self.uv_layers:
 220                         if u.unit is None:
 221                                 if not u.hidden:
 222                                         u.unit = free_unit
 223                                         free_unit += 1
 224
 225         def generate_material_uv(self):
 226                 self.uv_layers.append(FakeUvLayer("material_tex"))
 227                 self.assign_texture_units()
 228                 for f in self.faces:
 229                         f.uvs.append([((f.material_index+0.5)/len(self.materials), 0.5)]*len(f.vertices))
 230
 231         def split_vertices(self, find_group_func, progress, *args):
 232                 groups = []
 233                 for i in range(len(self.vertices)):
 234                         v = self.vertices[i]
 235                         for f in v.faces:
 236                                 f.flag = False
 237
 238                         vg = []
 239                         for f in v.faces:
 240                                 if not f.flag:
 241                                         vg.append(find_group_func(v, f, *args))
 242
 243                         groups.append(vg)
 244
 245                         if progress:
 246                                 progress.set_progress(i*0.5/len(self.vertices))
 247
 248                 for i in range(len(self.vertices)):
 249                         if len(groups[i])==1:
 250                                 continue
 251
 252                         for g in groups[i][1:]:
 253                                 v = Vertex(self.vertices[i])
 254                                 v.index = len(self.vertices)
 255                                 self.vertices.append(v)
 256
 257                                 v_edges = []
 258                                 v_edge_keys = set()
 259                                 for f in g:
 260                                         for e in f.edges:
 261                                                 if e.key in v_edge_keys or self.vertices[i] not in e.vertices:
 262                                                         continue
 263
 264                                                 e_faces_in_g = [c for c in e.faces if c in g]
 265                                                 boundary = len(e_faces_in_g)<len(e.faces)
 266                                                 v_edges.append((e, boundary, e_faces_in_g))
 267                                                 v_edge_keys.add(e.key)
 268
 269                                 for e, boundary, e_faces_in_g in v_edges:
 270                                         if boundary:
 271                                                 ne = Edge(e)
 272                                                 for c in e_faces_in_g:
 273                                                         e.faces.remove(c)
 274                                                         c.edges[c.edges.index(e)] = ne
 275                                                         ne.faces.append(c)
 276                                                 e = ne
 277                                         else:
 278                                                 del self.edges[e.key]
 279
 280                                         e.vertices[e.vertices.index(self.vertices[i])] = v
 281
 282                                         e.key = make_edge_key(e.vertices[0].index, e.vertices[1].index)
 283                                         self.edges[e.key] = e
 284
 285                                 for f in g:
 286                                         self.vertices[i].faces.remove(f)
 287                                         f.vertices[f.vertices.index(self.vertices[i])] = v
 288                                         v.faces.append(f)
 289
 290                         if progress:
 291                                 progress.set_progress(0.5+i*0.5/len(self.vertices))
 292
 293         def split_smooth(self, progress = None):
 294                 self.split_vertices(self.find_smooth_group, progress)
 295
 296         def split_uv(self, index, progress = None):
 297                 self.split_vertices(self.find_uv_group, progress, index)
 298
 299         def find_smooth_group(self, vertex, face):
 300                 face.flag = True
 301                 queue = [face]
 302
 303                 for f in queue:
 304                         for e in f.edges:
 305                                 other = e.other_face(f)
 306                                 if other not in vertex.faces:
 307                                         continue
 308
 309                                 if e.smooth:
 310                                         if not other.flag:
 311                                                 other.flag = True
 312                                                 queue.append(other)
 313
 314                 return queue
 315
 316         def find_uv_group(self, vertex, face, index):
 317                 uv = face.uvs[index][face.vertices.index(vertex)]
 318                 face.flag = True
 319                 group = [face]
 320                 for f in vertex.faces:
 321                         if not f.flag and f.uvs[index][f.vertices.index(vertex)]==uv:
 322                                 f.flag = True
 323                                 group.append(f)
 324                 return group
 325
 326         def compute_normals(self):
 327                 for v in self.vertices:
 328                         if v.faces:
 329                                 v.normal = mathutils.Vector()
 330                                 for f in v.faces:
 331                                         fv = f.pivot_vertices(v)
 332                                         edge1 = fv[1].co-fv[0].co
 333                                         edge2 = fv[-1].co-fv[0].co
 334                                         if edge1.length and edge2.length:
 335                                                 weight = 1
 336                                                 if len(f.get_edge(fv[0], fv[1]).faces)==1:
 337                                                         weight += 1
 338                                                 if len(f.get_edge(fv[0], fv[-1]).faces)==1:
 339                                                         weight += 1
 340                                                 v.normal += f.normal*edge1.angle(edge2)*weight
 341                                 if v.normal.length:
 342                                         v.normal.normalize()
 343                                 else:
 344                                         v.normal = mathutils.Vector((0, 0, 1))
 345                         else:
 346                                 # XXX Should use edges to compute normal
 347                                 v.normal = mathutils.Vector((0, 0, 1))
 348
 349         def compute_uv(self):
 350                 for v in self.vertices:
 351                         if v.faces:
 352                                 f = v.faces[0]
 353                                 i = f.vertices.index(v)
 354                                 v.uvs = [u[i] for u in f.uvs]
 355                         else:
 356                                 v.uvs = [(0.0, 0.0)]*len(self.uv_layers)
 357
 358         def compute_tbn(self, index):
 359                 if not self.uv_layers:
 360                         return
 361
 362                 for v in self.vertices:
 363                         v.tan = mathutils.Vector()
 364                         v.bino = mathutils.Vector()
 365                         for f in v.faces:
 366                                 fv = f.pivot_vertices(v)
 367                                 uv0 = fv[0].uvs[index]
 368                                 uv1 = fv[1].uvs[index]
 369                                 uv2 = fv[-1].uvs[index]
 370                                 du1 = uv1[0]-uv0[0]
 371                                 du2 = uv2[0]-uv0[0]
 372                                 dv1 = uv1[1]-uv0[1]
 373                                 dv2 = uv2[1]-uv0[1]
 374                                 edge1 = fv[1].co-fv[0].co
 375                                 edge2 = fv[-1].co-fv[0].co
 376                                 div = (du1*dv2-du2*dv1)
 377                                 if div:
 378                                         mul = edge1.angle(edge2)/div
 379                                         v.tan += (edge1*dv2-edge2*dv1)*mul
 380                                         v.bino += (edge2*du1-edge1*du2)*mul
 381
 382                         if v.tan.length:
 383                                 v.tan.normalize()
 384                         if v.bino.length:
 385                                 v.bino.normalize()
 386
 387         def sort_vertex_groups(self, max_groups):
 388                 for v in self.vertices:
 389                         if v.groups:
 390                                 v.groups = sorted(v.groups, key=(lambda g: g.weight), reverse=True)
 391                                 v.group_weight_scale = 1.0/sum(g.weight for g in v.groups[:max_groups])
 392
 393         def create_strip(self, face, max_len):
 394                 # Find an edge with another unused face next to it
 395                 edge = None
 396                 for e in face.edges:
 397                         other = e.other_face(face)
 398                         if other and not other.flag:
 399                                 edge = e
 400                                 break
 401
 402                 if not edge:
 403                         return None
 404
 405                 # Add initial vertices so that we'll complete the edge on the first
 406                 # iteration
 407                 vertices = face.pivot_vertices(*edge.vertices)
 408                 if len(vertices)==3:
 409                         result = [vertices[-1], vertices[0]]
 410                 else:
 411                         result = [vertices[-2], vertices[-1]]
 412
 413                 while 1:
 414                         face.flag = True
 415
 416                         vertices = face.pivot_vertices(*result[-2:])
 417                         k = len(result)%2
 418
 419                         # Quads need special handling because the winding of every other
 420                         # triangle in the strip is reversed
 421                         if len(vertices)==4 and not k:
 422                                 result.append(vertices[3])
 423                         result.append(vertices[2])
 424                         if len(vertices)==4 and k:
 425                                 result.append(vertices[3])
 426
 427                         if len(result)>=max_len:
 428                                 break
 429
 430                         # Hop over the last edge
 431                         edge = face.get_edge(*result[-2:])
 432                         face = edge.other_face(face)
 433                         if not face or face.flag:
 434                                 break
 435
 436                 return result