]> git.tdb.fi Git - libs/gl.git/blobdiff - blender/io_mspgl/mesh.py
Check the flat qualifier from the correct member
[libs/gl.git] / blender / io_mspgl / mesh.py
index 754e6ffc2d35460c0e474e7fc02e70b3e62c9568..e4db4afb2a2abae7262564828aa9cc821422961d 100644 (file)
@@ -1,4 +1,3 @@
-import bpy
 import math
 import mathutils
 import itertools
@@ -48,11 +47,9 @@ class Vertex:
                if vertex.__class__==Vertex:
                        self.uvs = vertex.uvs[:]
                        self.tan = vertex.tan
-                       self.bino = vertex.bino
                else:
                        self.uvs = []
                        self.tan = None
-                       self.bino = None
                self.index = vertex.index
                self.co = mathutils.Vector(vertex.co)
                self.normal = mathutils.Vector(vertex.normal)
@@ -69,8 +66,11 @@ class Vertex:
 
 
 class VertexGroup:
-       def __init__(self, group):
-               if group:
+       def __init__(self, *args):
+               if len(args)==2:
+                       self.group = args[0]
+                       self.weight = args[1]
+               elif len(args)==1 and args[0]:
                        self.group = group.group
                        self.weight = group.weight
                else:
@@ -78,6 +78,13 @@ class VertexGroup:
                        self.weight = 0.0
 
 
+class Batch:
+       def __init__(self, pt):
+               self.primitive_type = pt
+               self.patch_size = 0
+               self.vertices = []
+
+
 class Face:
        def __init__(self, face):
                self.index = face.index
@@ -88,6 +95,7 @@ class Face:
                self.normal = face.normal
                self.use_smooth = face.use_smooth
                self.material_index = face.material_index
+               self.splat_mask = 0
                self.flag = False
 
        def __cmp__(self, other):
@@ -157,11 +165,12 @@ class Mesh:
        def __init__(self, mesh):
                self.name = mesh.name
 
-               self.winding_test = mesh.winding_test
                self.smoothing = mesh.smoothing
                self.use_uv = mesh.use_uv
-               self.tbn_vecs = mesh.tbn_vecs
-               self.tbn_uvtex = mesh.tbn_uvtex
+               self.tangent_uvtex = mesh.tangent_uvtex
+               self.use_strips = mesh.use_strips
+               self.use_patches = mesh.use_patches
+               self.use_lines = mesh.use_lines
                self.vertex_groups = mesh.vertex_groups
 
                # Clone basic data
@@ -179,11 +188,24 @@ class Mesh:
                self.auto_smooth_angle = mesh.auto_smooth_angle
                self.max_groups_per_vertex = mesh.max_groups_per_vertex
 
+               # Check some material properties
+               from .material import Material
+               has_normal_maps = False
+               splat_material = None
+               for m in self.materials:
+                       mat = Material(m)
+                       for p in itertools.chain(mat.properties, *(s.properties for s in mat.sub_materials)):
+                               if p.tex_keyword=="normal_map" and p.texture:
+                                       has_normal_maps = True
+                                       break
+                       if mat.type=="splat":
+                               splat_material = mat
+
                # Clone only the desired UV layers
                if mesh.use_uv=='NONE' or not mesh.uv_layers:
                        self.uv_layers = []
                else:
-                       self.uv_layers = [UvLayer(u) for u in mesh.uv_layers]
+                       self.uv_layers = [UvLayer(u) for u in mesh.uv_layers if u.data]
 
                        # Assign texture unit numbers to UV layers that lack one
                        missing_unit = [u for u in self.uv_layers if u.unit is None]
@@ -195,21 +217,21 @@ class Mesh:
 
                        self.uv_layers = sorted(self.uv_layers, key=(lambda u: u.unit))
 
-                       if mesh.use_uv=='UNIT0':
+                       if mesh.use_uv=='UNIT0' and self.uv_layers:
                                self.uv_layers = [self.uv_layers[0]]
                                if self.uv_layers[0].unit!=0:
                                        self.uv_layers = []
 
                self.colors = None
-               if mesh.vertex_colors:
+               if mesh.vertex_colors and not splat_material:
                        self.colors = ColorLayer(mesh.vertex_colors[0])
 
                # 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:
-                               raise ValueError("Ngons are not supported")
+                       if len(f.vertices)>4 and not mesh.use.patches:
+                               raise ValueError("Unsupported face on mesh {}: N-gon".format(self.name))
 
                        f.vertices = [self.vertices[i] for i in f.vertices]
                        for v in f.vertices:
@@ -226,12 +248,37 @@ class Mesh:
                                v.edges.append(e)
 
                # Store loose edges as lines
-               if mesh.use_lines:
+               if mesh.use_lines and not mesh.use_patches:
                        self.lines = [Line(e) for e in self.edges if not e.faces]
                else:
                        self.lines = []
 
-               self.vertex_sequence = []
+               # Check if tangent vectors are needed
+               if mesh.tangent_vecs=='NO':
+                       self.tangent_vecs = False
+               elif mesh.tangent_vecs=='YES':
+                       self.tangent_vecs = True
+               elif mesh.tangent_vecs=='AUTO':
+                       self.tangent_vecs = has_normal_maps
+
+               # Collect splat weight sources if needed
+               self.splat_layers = []
+               self.splat_sources = []
+               if splat_material:
+                       names = {s.weight_source[0] for s in splat_material.sub_materials}
+                       self.splat_layers = [ColorLayer(l) for l in mesh.vertex_colors if l.name in names]
+
+                       layers_by_name = {l.name:l for l in self.splat_layers}
+                       for s in splat_material.sub_materials:
+                               if s.weight_source[0] is None:
+                                       self.splat_sources.append((None, None))
+                               else:
+                                       self.splat_sources.append((layers_by_name[s.weight_source[0]], "RGBA".index(s.weight_source[1])))
+
+                       self.vertex_groups = True
+                       self.max_groups_per_vertex = 3
+
+               self.batches = []
 
        def transform(self, matrix):
                for v in self.vertices:
@@ -239,19 +286,19 @@ class Mesh:
 
        def splice(self, other):
                if len(self.uv_layers)!=len(other.uv_layers):
-                       raise ValueError("Meshes have incompatible UV layers")
+                       raise ValueError("Meshes {} and {} have incompatible UV layers".format(self.name, other.name))
                for i, u in enumerate(self.uv_layers):
                        if u.name!=other.uv_layers[i].name:
-                               raise ValueError("Meshes have incompatible UV layers")
+                               raise ValueError("Meshes {} and {} have incompatible UV layers".format(self.name, other.name))
 
                # Merge materials and form a lookup from source material indices to the
                # merged material list
-               material_atlas = []
+               material_lookup = []
                for m in other.materials:
                        if m in self.materials:
-                               material_atlas.append(self.materials.index(m))
+                               material_lookup.append(self.materials.index(m))
                        else:
-                               material_atlas.append(len(self.materials))
+                               material_lookup.append(len(self.materials))
                                self.materials.append(m)
 
                # Append data and adjust indices where necessary.  Since the data is
@@ -282,7 +329,7 @@ class Mesh:
                        f.index += offset
                        f.loop_indices = range(f.loop_indices.start+offset, f.loop_indices.stop+offset)
                        if other.materials:
-                               f.material_index = material_atlas[f.material_index]
+                               f.material_index = material_lookup[f.material_index]
 
                offset = len(self.edges)
                self.edges += other.edges
@@ -292,7 +339,10 @@ class Mesh:
 
                self.lines += other.lines
 
-       def prepare_triangles(self, progress):
+       def prepare_triangles(self, task):
+               if self.use_patches:
+                       return
+
                face_count = len(self.faces)
                for i in range(face_count):
                        f = self.faces[i]
@@ -352,9 +402,9 @@ class Mesh:
                        f.normal = normals[1-cut_index]
                        nf.normal = normals[3-cut_index]
 
-                       progress.set_progress(i/face_count)
+                       task.set_progress(i/face_count)
 
-       def prepare_smoothing(self, progress):
+       def prepare_smoothing(self, task):
                smooth_limit = -1
                if self.smoothing=='NONE':
                        for f in self.faces:
@@ -367,14 +417,12 @@ class Mesh:
                for e in self.edges:
                        e.check_smooth(smooth_limit)
 
-               progress.push_task("Sharp edges", 0.0, 0.7)
-               self.split_vertices(self.find_smooth_group, progress)
+               subtask = task.task("Sharp edges", 0.7)
+               self.split_vertices(self.find_smooth_group, subtask)
 
                if self.smoothing!='BLENDER':
-                       progress.set_task("Updating normals", 0.7, 1.0)
-                       self.compute_normals(progress)
-
-               progress.pop_task()
+                       subtask = task.task("Updating normals", 1.0)
+                       self.compute_normals(subtask)
 
        def prepare_vertex_groups(self, obj):
                if not self.vertex_groups:
@@ -402,31 +450,7 @@ class Mesh:
                                for g in v.groups:
                                        g.group = group_index_map[g.group]
 
-       def apply_material_atlas(self, material_atlas):
-               for m in self.materials:
-                       if m.name not in material_atlas.material_names:
-                               raise Exception("Material atlas is not compatible with Mesh")
-
-               if self.use_uv=='NONE':
-                       return
-
-               layer = UvLayer("material_atlas")
-               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_atlas.get_material_uv(self.materials[f.material_index])
-                       for i in f.loop_indices:
-                               layer.uvs[i] = uv
-
-       def prepare_uv(self, progress):
+       def prepare_uv(self, task):
                # 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']
@@ -444,40 +468,38 @@ class Mesh:
                                        for i in f.loop_indices:
                                                l.uvs[i] = mathutils.Vector((*l.uvs[i], layer))
 
-               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:
-                       if self.tbn_uvtex:
+               # Split by the UV layer used for tangent vectors first so connectivity
+               # remains intact for tangent vector computation
+               tangent_layer_index = -1
+               if self.tangent_vecs:
+                       if self.tangent_uvtex:
                                uv_names = [u.name for u in self.uv_layers]
-                               if self.tbn_uvtex in uv_names:
-                                       tbn_layer_index = uv_names.index(self.tbn_uvtex)
+                               if self.tangent_uvtex in uv_names:
+                                       tangent_layer_index = uv_names.index(self.tangent_uvtex)
                        elif self.uv_layers[0].unit==0:
-                               tbn_layer_index = 0
-
-                       if tbn_layer_index>=0:
-                               prog_count += 1
-                               progress.push_task_slice("Computing TBN", 0, prog_count)
-                               self.split_vertices(self.find_uv_group, progress, tbn_layer_index)
-                               progress.set_task_slice(self.tbn_uvtex, 1, prog_count)
-                               self.compute_tbn(tbn_layer_index, progress)
-                               progress.pop_task()
-                               prog_step = 2
-                       else:
-                               raise Exception("TBN UV layer not found")
+                               tangent_layer_index = 0
+
+                       if tangent_layer_index<0:
+                               raise Exception("Invalid configuration on mesh {}: No tangent UV layer".format(self.name))
+
+               prog_count = len(self.uv_layers)
+               if tangent_layer_index>=0:
+                       prog_count += 1
+               task.set_slices(prog_count)
+
+               if tangent_layer_index>=0:
+                       subtask = task.next_slice("Computing tangents")
+                       self.split_vertices(self.find_uv_group, subtask, tangent_layer_index)
+                       subtask = task.next_slice(self.tangent_uvtex)
+                       self.compute_tangents(tangent_layer_index, subtask)
 
                # Split by the remaining UV layers
                for i, u in enumerate(self.uv_layers):
-                       if i==tbn_layer_index:
+                       if i==tangent_layer_index:
                                continue
 
-                       progress.push_task_slice(u.name, prog_step, prog_count)
-                       self.split_vertices(self.find_uv_group, progress, i)
-                       progress.pop_task()
-                       prog_step += 1
+                       subtask = task.next_slice(u.name)
+                       self.split_vertices(self.find_uv_group, subtask, i)
 
                # Copy UVs from layers to vertices
                for v in self.vertices:
@@ -489,11 +511,11 @@ class Mesh:
                        else:
                                v.uvs = [(0.0, 0.0)]*len(self.uv_layers)
 
-       def prepare_colors(self, progress):
+       def prepare_colors(self, task):
                if not self.colors:
                        return
 
-               self.split_vertices(self.find_color_group, progress)
+               self.split_vertices(self.find_color_group, task)
 
                for v in self.vertices:
                        if v.faces:
@@ -502,7 +524,44 @@ class Mesh:
                        else:
                                v.color = (1.0, 1.0, 1.0, 1.0)
 
-       def split_vertices(self, find_group_func, progress, *args):
+       def prepare_splat_weights(self, task):
+               if not self.splat_layers:
+                       return
+
+               splat_weights = []
+               remainder = None
+               for s in self.splat_sources:
+                       if s[0] is None:
+                               splat_weights.append(remainder)
+                       else:
+                               index = s[1]
+                               layer_values = [c[index] for c in s[0].colors]
+                               if remainder:
+                                       splat_weights.append([v*r for v, r in zip(layer_values, remainder)])
+                                       remainder = [(1-v)*r for v, r in zip(layer_values, remainder)]
+                               else:
+                                       splat_weights.append(layer_values)
+                                       remainder = [1-v for v in layer_values]
+
+               splat_weights = list(zip(*splat_weights))
+
+               for f in self.faces:
+                       for i in f.loop_indices:
+                               f.splat_mask |= sum(1<<j for j, w in enumerate(splat_weights[i]) if w>0)
+
+               self.split_vertices(self.find_splat_group, task)
+
+               for v in self.vertices:
+                       if v.faces:
+                               f = v.faces[0]
+                               weights = splat_weights[f.get_loop_index(v)]
+                               v.groups = [VertexGroup(i, w) for i, w in enumerate(weights) if (f.splat_mask>>i)&1]
+                       else:
+                               v.groups = []
+                       while len(v.groups)<self.max_groups_per_vertex:
+                               v.groups.append(VertexGroup(None))
+
+       def split_vertices(self, find_group_func, task, *args):
                vertex_count = len(self.vertices)
                for i in range(vertex_count):
                        v = self.vertices[i]
@@ -554,7 +613,7 @@ class Mesh:
                                        f.vertices[f.vertices.index(v)] = nv
                                        nv.faces.append(f)
 
-                       progress.set_progress(i/vertex_count)
+                       task.set_progress(i/vertex_count)
 
        def find_smooth_group(self, vertex, face):
                face.flag = True
@@ -600,7 +659,18 @@ class Mesh:
 
                return group
 
-       def compute_normals(self, progress):
+       def find_splat_group(self, vertex, face):
+               face.flag = True
+
+               group = [face]
+               for f in vertex.faces:
+                       if not f.flag and f.splat_mask==face.splat_mask:
+                               f.flag = True
+                               group.append(f)
+
+               return group
+
+       def compute_normals(self, task):
                for i, v in enumerate(self.vertices):
                        v.normal = mathutils.Vector()
                        for f in v.faces:
@@ -618,16 +688,13 @@ class Mesh:
                        else:
                                v.normal = mathutils.Vector((0, 0, 1))
 
-                       progress.set_progress(i/len(self.vertices))
+                       task.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
+       def compute_tangents(self, index, task):
                layer_uvs = self.uv_layers[index].uvs
 
                for i, v in enumerate(self.vertices):
                        v.tan = mathutils.Vector()
-                       v.bino = mathutils.Vector()
                        for f in v.faces:
                                vi = f.pivot_vertex(v)
                                uv0 = layer_uvs[f.loop_indices[vi[0]]]
@@ -643,20 +710,35 @@ class Mesh:
                                if div:
                                        mul = edge1.angle(edge2)/div
                                        v.tan += (edge1*dv2-edge2*dv1)*mul
-                                       v.bino += (edge2*du1-edge1*du2)*mul
 
                        if v.tan.length:
                                v.tan.normalize()
-                       if v.bino.length:
-                               v.bino.normalize()
 
-                       progress.set_progress(i/len(self.vertices))
+                       task.set_progress(i/len(self.vertices))
 
-       def prepare_sequence(self, progress):
-               progress.push_task("Reordering faces", 0.0, 0.5)
-               self.reorder_faces(progress)
+       def prepare_sequence(self, task):
+               if self.use_patches:
+                       subtask = task.task("Reordering patches", 0.5)
+                       self.reorder_patches(subtask)
 
-               progress.set_task("Building sequence", 0.5, 1.0)
+                       subtask = task.task("Building sequence", 1.0)
+                       self.build_patch_sequence(subtask)
+               else:
+                       subtask = task.task("Reordering faces", 0.5)
+                       self.reorder_faces(subtask)
+
+                       subtask = task.task("Building sequence", 1.0)
+                       if self.use_strips:
+                               self.build_tristrip_sequence(subtask)
+                       else:
+                               self.build_triangle_sequence(subtask)
+
+                       if self.use_lines:
+                               self.build_line_sequence()
+
+               self.reorder_vertices()
+
+       def build_tristrip_sequence(self, task):
                sequence = None
                for i, f in enumerate(self.faces):
                        if sequence:
@@ -680,16 +762,37 @@ class Mesh:
                                        sequence += to_add
 
                        if not sequence:
-                               sequence = f.vertices[:]
-                               self.vertex_sequence.append(sequence)
+                               self.batches.append(Batch("TRIANGLE_STRIP"))
+                               sequence = self.batches[-1].vertices
+                               sequence += f.vertices
 
-                       progress.set_progress(i/len(self.faces))
+                       task.set_progress(i/len(self.faces))
 
-               progress.pop_task()
+       def build_triangle_sequence(self, task):
+               batch = Batch("TRIANGLES")
+               for f in self.faces:
+                       batch.vertices += f.vertices
+               self.batches.append(batch)
 
-               self.reorder_vertices()
+       def build_line_sequence(self):
+               batch = Batch("LINES")
+               for l in self.lines:
+                       batch.vertices += l.vertices
+               self.batches.append(batch)
+
+       def build_patch_sequence(self, task):
+               current_size = 0
+               sequence = None
+               for f in self.faces:
+                       if len(f.vertices)!=current_size:
+                               current_size = len(f.vertices)
+                               self.batches.append(Batch("PATCHES"))
+                               self.batches[-1].patch_size = current_size
+                               sequence = self.batches[-1].vertices
+
+                       sequence += f.vertices
 
-       def reorder_faces(self, progress):
+       def reorder_faces(self, task):
                # Tom Forsyth's vertex cache optimization algorithm
                # http://eelpi.gotdns.org/papers/fast_vert_cache_opt.html
 
@@ -707,7 +810,8 @@ class Mesh:
                # 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)
+                       if vi[1]:
+                               vi[0] = valence_boost_scale*(vi[1]**valence_boost_power)
 
                face = None
                reordered_faces = []
@@ -765,34 +869,67 @@ class Mesh:
                        del cached_vertices[max_cache_size:]
 
                        n_processed += 1
-                       progress.set_progress(n_processed/len(self.faces))
+                       task.set_progress(n_processed/len(self.faces))
 
                self.faces = reordered_faces
                for i, f in enumerate(self.faces):
                        f.index = i
 
+       def reorder_patches(self, task):
+               for f in self.faces:
+                       f.flag = False
+
+               reordered_faces = []
+               n_processed = 0
+
+               while 1:
+                       current_size = 0
+
+                       for f in self.faces:
+                               if f.flag:
+                                       continue
+
+                               if not current_size:
+                                       current_size = len(f.vertices)
+                               elif len(f.vertices)!=current_size:
+                                       continue
+
+                               reordered_faces.append(f)
+                               f.flag = True
+
+                               n_processed += 1
+                               task.set_progress(n_processed/len(self.faces))
+
+                       if not current_size:
+                               break
+
        def reorder_vertices(self):
                for v in self.vertices:
                        v.index = -1
 
                reordered_vertices = []
-               for s in self.vertex_sequence:
-                       for v in s:
+               for b in self.batches:
+                       for v in b.vertices:
                                if v.index<0:
                                        v.index = len(reordered_vertices)
                                        reordered_vertices.append(v)
 
+               for v in self.vertices:
+                       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 create_mesh_from_object(context, obj, progress, *, material_atlas=None):
+def create_mesh_from_object(ctx, obj):
        if obj.type!="MESH":
-               raise Exception("Object is not a mesh")
+               raise Exception("Object {} is not a mesh".format(obj.name))
 
-       progress.push_task("Preparing mesh", 0.0, 0.2)
+       task = ctx.task("Collecting mesh data", 0.2)
 
        objs = [(obj, mathutils.Matrix())]
        i = 0
@@ -803,7 +940,7 @@ def create_mesh_from_object(context, obj, progress, *, material_atlas=None):
                        if c.type=="MESH" and c.compound:
                                objs.append((c, m*c.matrix_local))
 
-       dg = context.evaluated_depsgraph_get()
+       dg = ctx.context.evaluated_depsgraph_get()
 
        mesh = None
        for o, m in objs:
@@ -811,14 +948,13 @@ def create_mesh_from_object(context, obj, progress, *, material_atlas=None):
                bmesh = eval_obj.to_mesh()
 
                # Object.to_mesh does not copy custom properties
-               bmesh.winding_test = o.data.winding_test
                bmesh.smoothing = o.data.smoothing
                bmesh.use_lines = o.data.use_lines
                bmesh.vertex_groups = o.data.vertex_groups
                bmesh.max_groups_per_vertex = o.data.max_groups_per_vertex
                bmesh.use_uv = o.data.use_uv
-               bmesh.tbn_vecs = o.data.tbn_vecs
-               bmesh.tbn_uvtex = o.data.tbn_uvtex
+               bmesh.tangent_vecs = o.data.tangent_vecs
+               bmesh.tangent_uvtex = o.data.tangent_uvtex
 
                me = Mesh(bmesh)
                me.transform(m)
@@ -834,22 +970,21 @@ def create_mesh_from_object(context, obj, progress, *, material_atlas=None):
 
        mesh.name = obj.data.name
 
-       if material_atlas:
-               mesh.apply_material_atlas(material_atlas)
-
-       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", 0.5, 0.6)
-       mesh.prepare_vertex_groups(obj)
-       progress.set_task("Preparing UVs", 0.6, 0.75)
-       mesh.prepare_uv(progress)
-       progress.set_task("Preparing vertex colors", 0.75, 0.85)
-       mesh.prepare_colors(progress)
-       progress.set_task("Render sequence", 0.85, 1.0)
-       mesh.prepare_sequence(progress)
-
-       progress.pop_task()
+       task = ctx.task("Triangulating", 0.3)
+       mesh.prepare_triangles(task)
+       task = ctx.task("Smoothing", 0.5)
+       mesh.prepare_smoothing(task)
+       if mesh.splat_sources:
+               task = ctx.task("Splat weights", 0.6)
+               mesh.prepare_splat_weights(task)
+       else:
+               task = ctx.task("Vertex groups", 0.6)
+               mesh.prepare_vertex_groups(obj)
+       task = ctx.task("Preparing UVs", 0.75)
+       mesh.prepare_uv(task)
+       task = ctx.task("Preparing vertex colors", 0.85)
+       mesh.prepare_colors(task)
+       task = ctx.task("Render sequence", 1.0)
+       mesh.prepare_sequence(task)
 
        return mesh