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