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