import bpy
import math
import mathutils
+import itertools
def make_edge_key(i1, i2):
return (min(i1, i2), max(i1, i2))
def __init__(self, edge):
if edge.__class__==Edge:
self._edge = edge._edge
- self.vertices = edge.vertices[:]
self.smooth = edge.smooth
else:
self._edge = edge
self.smooth = False
- self.key = edge.key
+ if edge:
+ self.vertices = edge.vertices[:]
+ self.key = edge.key
+ else:
+ self.vertices = []
+ self.key = None
self.faces = []
def __getattr__(self, attr):
self.tan = None
self.bino = None
self.index = vertex.index
- self.co = vertex.co
- self.normal = vertex.normal
+ self.co = mathutils.Vector(vertex.co)
+ self.normal = mathutils.Vector(vertex.normal)
self.flag = False
self.edges = []
self.faces = []
if flags[i] and not flags[(i+l-1)%l]:
return self.vertices[i:]+self.vertices[:i]
- def get_edge(self, v1, v2):
+ def get_edge(self, v1, v2):
key = make_edge_key(v1.index, v2.index)
for e in self.edges:
if e.key==key:
if type(arg)==str:
self._layer = None
self.name = arg
+ self.uvs = []
else:
self._layer = arg
self.name = arg.name
- self.uvs = [d.uv for d in self.data]
+ self.uvs = [mathutils.Vector(d.uv) for d in self.data]
self.unit = None
self.hidden = False
class Mesh:
def __init__(self, mesh):
self._mesh = mesh
+ self.name = mesh.name
self.winding_test = mesh.winding_test
self.tbn_vecs = mesh.tbn_vecs
self.vertex_groups = mesh.vertex_groups
- self.vertices = [Vertex(v) for v in self.vertices]
- self.faces = [Face(f) for f in self.polygons]
- self.edges = [Edge(e) for e in self.edges]
- self.loops = self.loops[:]
+ # Clone basic data
+ self.vertices = [Vertex(v) for v in mesh.vertices]
+ for v in self.vertices:
+ v.groups = [VertexGroup(g) for g in v.groups]
+
+ self.faces = [Face(f) for f in mesh.polygons]
+ self.edges = [Edge(e) for e in mesh.edges]
+ self.loops = mesh.loops[:]
+ self.materials = mesh.materials[:]
- self.materials = self.materials[:]
- if self.use_uv=='NONE' or not self.uv_layers:
+ # Clone only the desired UV layers
+ if self.use_uv=='NONE' or not mesh.uv_layers:
self.uv_layers = []
else:
- self.uv_layers = [UvLayer(u) for u in self.uv_layers]
- self.uv_layers = sorted([u for u in self.uv_layers if not u.hidden], key=(lambda u: (u.unit or 1000, u.name)))
+ self.uv_layers = [UvLayer(u) for u in mesh.uv_layers]
- if self.use_uv=='UNIT0':
- self.uv_layers = [self.uv_layers[0]]
+ # Assign texture unit numbers to UV layers that lack one
+ missing_unit = [u for u in self.uv_layers if u.unit is None]
+ if missing_unit:
+ missing_unit = sorted(missing_unit, key=(lambda u: u.name))
+ used_units = [u.unit for u in self.uv_layers if u.unit is not None]
+ for u, n in zip(missing_unit, (i for i in itertools.count() if i not in used_units)):
+ u.unit = n
- next_unit = max((u.unit+1 for u in self.uv_layers if u.unit is not None), default=0)
- for u in self.uv_layers:
- if not u.unit:
- u.unit = next_unit
- next_unit += 1
+ self.uv_layers = sorted(self.uv_layers, key=(lambda u: u.unit))
- for v in self.vertices:
- v.groups = [VertexGroup(g) for g in v.groups]
+ if self.use_uv=='UNIT0':
+ self.uv_layers = [self.uv_layers[0]]
+ if self.uv_layers[0].unit!=0:
+ self.uv_layers = []
+ # Rewrite links between elements to point to cloned data, or create links
+ # where they don't exist
edge_map = {e.key: e for e in self.edges}
for f in self.faces:
if len(f.vertices)>4:
for v in e.vertices:
v.edges.append(e)
+ # Store loose edges as lines
if self.use_lines:
self.lines = [Line(e) for e in self.edges if not e.faces]
else:
self.lines = []
+ self.vertex_sequence = []
+
def __getattr__(self, attr):
return getattr(self._mesh, attr)
if u.name!=other.uv_layers[i].name:
raise ValueError("Meshes have incompatible UV layers")
+ # Merge materials and form a lookup from source material indices to the
+ # merged material list
material_map = []
for m in other.materials:
if m in self.materials:
material_map.append(len(self.materials))
self.materials.append(m)
+ # Append data and adjust indices where necessary. Since the data is
+ # spliced from the source mesh, rebuilding references is not necessary.
for i, u in enumerate(self.uv_layers):
u.uvs += other.uv_layers[i].uvs
self.lines += other.lines
+ def prepare_triangles(self, progress):
+ face_count = len(self.faces)
+ for i in range(face_count):
+ f = self.faces[i]
+ nverts = len(f.vertices)
+ if nverts==3:
+ continue
+
+ # Calculate normals at each vertex of the face
+ edge_vecs = []
+ for j in range(nverts):
+ edge_vecs.append(f.vertices[(j+1)%nverts].co-f.vertices[j].co)
+
+ normals = []
+ for j in range(nverts):
+ normals.append(edge_vecs[j-1].cross(edge_vecs[j]).normalized())
+
+ # Check which diagonal results in a flatter triangulation
+ flatness1 = normals[0].dot(normals[2])
+ flatness2 = normals[1].dot(normals[3])
+ cut_index = 1 if flatness1>flatness2 else 0
+
+ nf = Face(f)
+ nf.index = len(self.faces)
+ self.faces.append(nf)
+
+ ne = Edge(None)
+ ne.index = len(self.edges)
+ self.edges.append(ne)
+
+ nf.vertices = [f.vertices[cut_index], f.vertices[2], f.vertices[3]]
+ nf.loop_indices = [f.loop_indices[cut_index], f.loop_indices[2], f.loop_indices[3]]
+ for v in nf.vertices:
+ v.faces.append(nf)
+
+ ne.vertices = [f.vertices[cut_index], f.vertices[2+cut_index]]
+ for v in ne.vertices:
+ v.edges.append(ne)
+ ne.key = make_edge_key(ne.vertices[0].index, ne.vertices[1].index)
+ ne.smooth = True
+
+ f.vertices[3-cut_index].faces.remove(f)
+ del f.vertices[3-cut_index]
+ f.loop_indices = [f.loop_indices[0], f.loop_indices[1], f.loop_indices[2+cut_index]]
+
+ ne.faces = [f, nf]
+ if cut_index==0:
+ nf.edges = [ne, f.edges[2], f.edges[3]]
+ f.edges = [f.edges[0], f.edges[1], ne]
+ else:
+ nf.edges = [f.edges[1], f.edges[2], ne]
+ f.edges = [f.edges[0], ne, f.edges[3]]
+ for e in nf.edges:
+ if e!=ne:
+ e.faces.remove(f)
+ e.faces.append(nf)
+
+ f.normal = normals[1-cut_index]
+ nf.normal = normals[3-cut_index]
+
+ progress.set_progress(i/face_count)
+
def prepare_smoothing(self, progress):
smooth_limit = -1
if self.smoothing=='NONE':
for g in v.groups:
g.group = group_index_map[g.group]
- def prepare_uv(self, obj, progress):
- if obj.material_tex and self.use_uv!='NONE':
- layer = UvLayer("material_tex")
+ def apply_material_map(self, material_map):
+ for m in self.materials:
+ if m not in material_map.materials:
+ raise Exception("Material map is not compatible with Mesh")
- if self.use_uv=='UNIT0':
- self.uv_layers = [layer]
- layer.unit = 0
- else:
- self.uv_layers.append(layer)
- layer.unit = max((u.unit+1 for u in self.uv_layers if u.unit is not None), default=0)
+ if self.use_uv=='NONE':
+ return
- layer.uvs = [None]*len(self.loops)
- for f in self.faces:
- uv = mathutils.Vector(((f.material_index+0.5)/len(self.materials), 0.5))
- for i in f.loop_indices:
- layer.uvs[i] = uv
+ layer = UvLayer("material_map")
+ if self.use_uv=='UNIT0':
+ self.uv_layers = [layer]
+ layer.unit = 0
+ else:
+ self.uv_layers.append(layer)
+ used_units = [u.unit for u in self.uv_layers]
+ layer.unit = next(i for i in itertools.count() if i not in used_units)
+ self.uv_layers.sort(key=lambda u: u.unit)
+ layer.uvs = [(0.0, 0.0)]*len(self.loops)
+ for f in self.faces:
+ uv = material_map.get_material_uv(self.materials[f.material_index])
+ for i in f.loop_indices:
+ layer.uvs[i] = uv
+
+ def prepare_uv(self, progress):
+ # Form a list of UV layers referenced by materials with the array atlas
+ # property set
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']
array_uv_layers = [u for u in self.uv_layers if u.name in array_uv_layers]
for i in f.loop_indices:
l.uvs[i] = mathutils.Vector((*l.uvs[i], layer))
+ # Copy UVs from layers to faces
for f in self.faces:
for u in self.uv_layers:
f.uvs.append([u.uvs[i] for i in f.loop_indices])
prog_count = len(self.uv_layers)
prog_step = 0
+ # Split by the UV layer used for TBN vectors first so connectivity
+ # remains intact for TBN vector computation
tbn_layer_index = -1
if self.tbn_vecs:
uv_names = [u.name for u in self.uv_layers]
progress.pop_task()
prog_step = 2
+ # Split by the remaining UV layers
for i, u in enumerate(self.uv_layers):
if i==tbn_layer_index:
continue
progress.pop_task()
prog_step += 1
+ # Copy UVs from faces to vertices
for v in self.vertices:
if v.faces:
+ # All faces still connected to the vertex have the same UV value
f = v.faces[0]
i = f.vertices.index(v)
v.uvs = [u[i] for u in f.uvs]
for f in v.faces:
f.flag = False
+ # Find all groups of faces on this vertex
groups = []
for f in v.faces:
if not f.flag:
groups.append(find_group_func(v, f, *args))
+ # Give groups after the first separate copies of the vertex
for g in groups[1:]:
nv = Vertex(v)
nv.index = len(self.vertices)
continue
if len(e_faces_in_g)<len(e.faces):
+ # Create a copy of an edge at the boundary of the group
ne = Edge(e)
ne.index = len(self.edges)
self.edges.append(ne)
e.key = make_edge_key(e.vertices[0].index, e.vertices[1].index)
+ # Filter out any edges that were removed from the original vertex
v.edges = [e for e in v.edges if v in e.vertices]
for f in g:
edge1 = fv[1].co-fv[0].co
edge2 = fv[-1].co-fv[0].co
if edge1.length and edge2.length:
+ # Use the angle between edges as a weighting factor. This gives
+ # more consistent normals on bends with an inequal number of
+ # faces on each side.
v.normal += f.normal*edge1.angle(edge2)
if v.normal.length:
progress.set_progress(i/len(self.vertices))
def compute_tbn(self, index, progress):
+ # This function is called at an early stage during UV preparation when
+ # face UVs are not available yet
layer_uvs = self.uv_layers[index].uvs
for i, v in enumerate(self.vertices):
progress.set_progress(i/len(self.vertices))
+ def prepare_sequence(self, progress):
+ progress.push_task("Reordering faces", 0.0, 0.5)
+ self.reorder_faces(progress)
+
+ progress.set_task("Building sequence", 0.5, 1.0)
+ sequence = None
+ for i, f in enumerate(self.faces):
+ if sequence:
+ if len(sequence)==3:
+ # Rotate the first three vertices so that the new face can be added
+ if sequence[0] in f.vertices and sequence[1] not in f.vertices:
+ sequence.append(sequence[0])
+ del sequence[0]
+ elif sequence[2] not in f.vertices and sequence[1] in f.vertices:
+ sequence.insert(0, sequence[-1])
+ del sequence[-1]
+
+ if sequence[-1] not in f.vertices:
+ sequence = None
+ else:
+ to_add = [v for v in f.vertices if v!=sequence[-1] and v!=sequence[-2]]
+ if len(to_add)==2:
+ if (f.vertices[1]==sequence[-1]) != (len(sequence)%2==1):
+ to_add.reverse()
+ sequence.append(sequence[-1])
+ sequence += to_add
+
+ if not sequence:
+ sequence = f.vertices[:]
+ self.vertex_sequence.append(sequence)
+
+ progress.set_progress(i/len(self.faces))
+
+ progress.pop_task()
+
+ self.reorder_vertices()
+
+ def reorder_faces(self, progress):
+ # Tom Forsyth's vertex cache optimization algorithm
+ # http://eelpi.gotdns.org/papers/fast_vert_cache_opt.html
+
+ for f in self.faces:
+ f.flag = False
+
+ last_triangle_score = 0.75
+ cache_decay_power = 1.5
+ valence_boost_scale = 2.0
+ valence_boost_power = -0.5
+
+ max_cache_size = 32
+ cached_vertices = []
+
+ # Keep track of the score and number of unused faces for each vertex
+ vertex_info = [[0, len(v.faces)] for v in self.vertices]
+ for vi in vertex_info:
+ vi[0] = valence_boost_scale*(vi[1]**valence_boost_power)
+
+ face = None
+ reordered_faces = []
+
+ n_processed = 0
+ while 1:
+ if not face:
+ # Previous iteration gave no candidate for best face (or this is
+ # the first iteration). Scan all faces for the highest score.
+ best_score = 0
+ for f in self.faces:
+ if f.flag:
+ continue
+
+ score = sum(vertex_info[v.index][0] for v in f.vertices)
+ if score>best_score:
+ best_score = score
+ face = f
+
+ if not face:
+ break
+
+ reordered_faces.append(face)
+ face.flag = True
+
+ for v in face.vertices:
+ vertex_info[v.index][1] -= 1
+
+ # Shuffle the vertex into the front of the cache
+ if v in cached_vertices:
+ cached_vertices.remove(v)
+ cached_vertices.insert(0, v)
+
+ # Update scores for all vertices in the cache
+ for i, v in enumerate(cached_vertices):
+ score = 0
+ if i<3:
+ score += last_triangle_score
+ elif i<max_cache_size:
+ score += (1-(i-3)/(max_cache_size-3))**cache_decay_power
+ if vertex_info[v.index][1]:
+ score += valence_boost_scale*(vertex_info[v.index][1]**valence_boost_power)
+ vertex_info[v.index][0] = score
+
+ face = None
+ best_score = 0
+ for v in cached_vertices:
+ for f in v.faces:
+ if not f.flag:
+ score = sum(vertex_info[fv.index][0] for fv in f.vertices)
+ if score>best_score:
+ best_score = score
+ face = f
+
+ del cached_vertices[max_cache_size:]
+
+ n_processed += 1
+ progress.set_progress(n_processed/len(self.faces))
+
+ self.faces = reordered_faces
+ for i, f in enumerate(self.faces):
+ f.index = i
+
+ def reorder_vertices(self):
+ for v in self.vertices:
+ v.index = -1
+
+ reordered_vertices = []
+ for s in self.vertex_sequence:
+ for v in s:
+ if v.index<0:
+ v.index = len(reordered_vertices)
+ reordered_vertices.append(v)
+
+ self.vertices = reordered_vertices
+
+ for e in self.edges:
+ e.key = make_edge_key(e.vertices[0].index, e.vertices[1].index)
+
def drop_references(self):
for v in self.vertices:
v._vertex = None
u._layer = None
self._mesh = None
- def create_strip(self, face, max_len):
- # Find an edge with another unused face next to it
- edge = None
- for e in face.edges:
- other = e.other_face(face)
- if other and not other.flag:
- edge = e
- break
-
- if not edge:
- return None
-
- # Add initial vertices so that we'll complete the edge on the first
- # iteration
- vertices = face.pivot_vertices(*edge.vertices)
- if len(vertices)==3:
- result = [vertices[-1], vertices[0]]
- else:
- result = [vertices[-2], vertices[-1]]
-
- while 1:
- face.flag = True
-
- vertices = face.pivot_vertices(*result[-2:])
- k = len(result)%2
- # Quads need special handling because the winding of every other
- # triangle in the strip is reversed
- if len(vertices)==4 and not k:
- result.append(vertices[3])
- result.append(vertices[2])
- if len(vertices)==4 and k:
- result.append(vertices[3])
-
- if len(result)>=max_len:
- break
-
- # Hop over the last edge
- edge = face.get_edge(*result[-2:])
- face = edge.other_face(face)
- if not face or face.flag:
- break
-
- return result
-
-def create_mesh_from_object(context, obj, progress):
+def create_mesh_from_object(context, obj, progress, *, material_map=None):
if obj.type!="MESH":
raise Exception("Object is not a mesh")
- progress.push_task("Preparing mesh", 0.0, 0.3)
+ progress.push_task("Preparing mesh", 0.0, 0.2)
objs = [(obj, mathutils.Matrix())]
i = 0
else:
mesh = me
- progress.set_task("Smoothing", 0.3, 0.6)
+ mesh.name = obj.data.name
+
+ if material_map:
+ mesh.apply_material_map(material_map)
+
+ progress.set_task("Triangulating", 0.2, 0.3)
+ mesh.prepare_triangles(progress)
+ progress.set_task("Smoothing", 0.3, 0.5)
mesh.prepare_smoothing(progress)
- progress.set_task("Vertex groups", 0.6, 0.7)
+ progress.set_task("Vertex groups", 0.5, 0.6)
mesh.prepare_vertex_groups(obj)
- progress.set_task("Preparing UVs", 0.7, 1.0)
- mesh.prepare_uv(obj, progress)
+ progress.set_task("Preparing UVs", 0.6, 0.8)
+ mesh.prepare_uv(progress)
+ progress.set_task("Render sequence", 0.8, 1.0)
+ mesh.prepare_sequence(progress)
+ # Discard the temporary Blender meshes after making sure there's no
+ # references to the data
mesh.drop_references()
for m in bmeshes:
bpy.data.meshes.remove(m)