fix handling of mesh loops

Fixes UVs, vertex colousr and adds support for custom normals. (Probably Blender's API can be confusing.)
This commit is contained in:
SleepKiller 2019-11-15 20:02:04 +13:00
parent c12fc862b0
commit 107dd2e8bf
1 changed files with 23 additions and 48 deletions

View File

@ -2,7 +2,7 @@
Model objects. """
import bpy
from typing import List, Set, Dict
from typing import List, Set, Dict, Tuple
from itertools import zip_longest
from .msh_model import *
from .msh_model_utilities import *
@ -64,21 +64,17 @@ def create_mesh_geometry(mesh: bpy.types.Mesh) -> List[GeometrySegment]:
""" Creates a list of GeometrySegment objects from a Blender mesh.
Does NOT create triangle strips in the GeometrySegment however. """
if mesh.has_custom_normals:
mesh.calc_normals_split()
mesh.validate_material_indices()
mesh.calc_loop_triangles()
if len(mesh.materials) != 0:
return create_mesh_geometry_with_materials(mesh)
material_count = max(len(mesh.materials), 1)
return [create_mesh_geometry_without_materials(mesh)]
def create_mesh_geometry_with_materials(mesh: bpy.types.Mesh) -> List[GeometrySegment]:
""" Creates a list of GeometrySegment objects from a Blender mesh
that references materials. """
segments: List[GeometrySegment] = [GeometrySegment() for i in range(len(mesh.materials))]
vertex_remap: List[Dict[int, int]] = [dict() for i in range(len(mesh.materials))]
polygons: List[Set[int]] = [set() for i in range(len(mesh.materials))]
segments: List[GeometrySegment] = [GeometrySegment() for i in range(material_count)]
vertex_remap: List[Dict[Tuple(int, int), int]] = [dict() for i in range(material_count)]
polygons: List[Set[int]] = [set() for i in range(material_count)]
if mesh.vertex_colors.active is not None:
for segment in segments:
@ -87,69 +83,48 @@ def create_mesh_geometry_with_materials(mesh: bpy.types.Mesh) -> List[GeometrySe
for segment, material in zip(segments, mesh.materials):
segment.material_name = material.name
def add_vertex(material_index: int, index : int) -> int:
def add_vertex(material_index: int, vertex_index: int, loop_index: int) -> int:
nonlocal segments, vertex_remap
segment = segments[material_index]
remap = vertex_remap[material_index]
if index in remap:
return remap[index]
if (vertex_index, loop_index) in remap:
return remap[(vertex_index, loop_index)]
new_index: int = len(segment.positions)
remap[index] = new_index
remap[(vertex_index, loop_index)] = new_index
segment.positions.append(mesh.vertices[index].co.copy())
segment.normals.append(mesh.vertices[index].normal.copy())
segment.positions.append(mesh.vertices[vertex_index].co.copy())
if mesh.has_custom_normals:
segment.normals.append(mesh.loops[loop_index].normal.copy())
else:
segment.normals.append(mesh.vertices[vertex_index].normal.copy())
if mesh.uv_layers.active is None:
segment.texcoords.append(Vector((0.0, 0.0)))
else:
segment.texcoords.append(mesh.uv_layers.active.data[index].uv.copy())
segment.texcoords.append(mesh.uv_layers.active.data[loop_index].uv.copy())
if segment.colors is not None:
segment.colors.append([v for v in mesh.vertex_colors.active.data[index].color])
segment.colors.append([v for v in mesh.vertex_colors.active.data[loop_index].color])
return new_index
for tri in mesh.loop_triangles:
polygons[tri.material_index].add(tri.polygon_index)
segments[tri.material_index].triangles.append([add_vertex(tri.material_index, i) for i in tri.vertices])
segments[tri.material_index].triangles.append(
[add_vertex(tri.material_index, v, l) for v, l in zip(tri.vertices, tri.loops)])
for segment, remap, polys in zip(segments, vertex_remap, polygons):
for poly_index in polys:
poly = mesh.polygons[poly_index]
segment.polygons.append([remap[i] for i in poly.vertices])
segment.polygons.append([remap[(v, l)] for v, l in zip(poly.vertices, poly.loop_indices)])
return segments
def create_mesh_geometry_without_materials(mesh: bpy.types.Mesh) -> GeometrySegment:
""" Creates a list of GeometrySegment objects from a Blender mesh
that doesn't references materials. """
segment = GeometrySegment()
for tri in mesh.loop_triangles:
segment.triangles.append([i for i in tri.vertices])
for vertex in mesh.vertices:
segment.positions.append(vertex.co.copy())
segment.normals.append(vertex.normal.copy())
if mesh.uv_layers.active is None:
segment.texcoords = [Vector((0.0, 0.0))] * len(mesh.vertices)
else:
segment.texcoords = [texcoords.uv.copy() for texcoords in mesh.uv_layers.active.data]
if mesh.vertex_colors.active is not None:
segment.colors = [[v for v in color.color] for color in mesh.vertex_colors.active.data]
for polygon in mesh.polygons:
segment.polygons.append([v for v in polygon.vertices])
return segment
def get_object_worldspace_scale(obj: bpy.types.Object) -> Vector:
""" Get the worldspace scale transform for a Blender object. """