fix(ymap): error when loading cargen mesh .obj

Blender 4.0 removed `bpy.ops.import_scene.obj`. Refactored the .obj
reader used in the archetype extension gizmos into its own module
to use it in ymap code. Also added tests for this .obj reader.

Fixes Sollumz#825.

shared/obj_reader.py

@@ -0,0 +1,57 @@
+"""
+Simple Wavefront .obj reader for loading Sollumz builtin models. Only supports
+vertices (`v`) and triangular faces (`f` with three vertex indices).
+"""
+
+import bpy
+import io
+import numpy as np
+from numpy.typing import NDArray
+from typing import NamedTuple
+from pathlib import Path
+
+
+class ObjMesh(NamedTuple):
+    vertices: NDArray[np.float32]
+    indices: NDArray[np.uint16]
+
+    def as_vertices_only(self) -> NDArray[np.float32]:
+        return self.vertices[self.indices.flatten()]
+
+    def as_bpy_mesh(self, name: str) -> bpy.types.Mesh:
+        mesh = bpy.data.meshes.new(name)
+        mesh.from_pydata(self.vertices, [], self.indices)
+        return mesh
+
+
+def obj_read(obj_io: io.TextIOBase) -> ObjMesh:
+    vertices = []
+    indices = []
+    for line in obj_io.readlines():
+        line = line.strip()
+        c = line[0] if len(line) > 0 else None
+        match c:
+            case "v":
+                x, y, z = line.strip("v ").split(" ")
+                vertices.extend((float(x), float(y), float(z)))
+            case "f":
+                v0, v1, v2 = line.strip("f ").split(" ")
+                indices.extend((int(v0) - 1, int(v1) - 1, int(v2) - 1))
+            case _:
+                # ignore unknown/unsupported elements
+                pass
+
+    return ObjMesh(
+        vertices=np.reshape(np.array(vertices, dtype=np.float32), (-1, 3)),
+        indices=np.reshape(np.array(indices, dtype=np.uint16), (-1, 3))
+    )
+
+
+def obj_read_from_file(file_path: Path) -> ObjMesh:
+    with file_path.open("r") as f:
+        return obj_read(f)
+
+
+def obj_read_from_str(obj_str: str) -> ObjMesh:
+    with io.StringIO(obj_str) as s:
+        return obj_read(s)

tests/test_obj_reader.py

@@ -0,0 +1,109 @@
+import bpy
+import pytest
+import numpy as np
+from numpy.testing import assert_array_equal
+from pathlib import Path
+from ..shared.obj_reader import obj_read_from_str, obj_read_from_file, ObjMesh
+
+
+def test_obj_read():
+    obj = obj_read_from_str("""
+        v 1.2 3.4 5.6
+        v 2.0 4.0 6.0
+        v 10.0 5.0 10.0
+        v 1.0 2.0 3.0
+        f 1 2 3
+        f 4 3 1
+    """)
+
+    assert obj is not None
+
+    assert_array_equal(obj.vertices, np.array([
+        [1.2, 3.4, 5.6],
+        [2.0, 4.0, 6.0],
+        [10.0, 5.0, 10.0],
+        [1.0, 2.0, 3.0],
+    ], dtype=np.float32))
+
+    assert_array_equal(obj.indices, np.array([
+        [0, 1, 2],
+        [3, 2, 0],
+    ], dtype=np.uint16))
+
+
+def test_obj_read_ignores_comments_and_unknown_elements():
+    obj = obj_read_from_str("""
+        # comment
+        v 1.0 2.0 3.0
+        # other comment
+        u unknown
+        f 1 2 3
+    """)
+
+    assert obj is not None
+
+    assert_array_equal(obj.vertices, np.array([
+        [1.0, 2.0, 3.0],
+    ], dtype=np.float32))
+
+    assert_array_equal(obj.indices, np.array([
+        [0, 1, 2],
+    ], dtype=np.uint16))
+
+
+def test_obj_as_vertices_only():
+    obj_mesh = ObjMesh(
+        vertices=np.array([
+            [1.0, 2.0, 3.0],
+            [4.0, 5.0, 6.0],
+            [7.0, 8.0, 9.0],
+        ], dtype=np.float32),
+        indices=np.array([
+            [0, 1, 2],
+            [2, 1, 0],
+        ], dtype=np.uint16)
+    )
+
+    obj_mesh_vertices = obj_mesh.as_vertices_only()
+    assert_array_equal(obj_mesh_vertices, np.array([
+        [1.0, 2.0, 3.0],
+        [4.0, 5.0, 6.0],
+        [7.0, 8.0, 9.0],
+        [7.0, 8.0, 9.0],
+        [4.0, 5.0, 6.0],
+        [1.0, 2.0, 3.0],
+    ]))
+
+
+@pytest.mark.parametrize("obj_relative_file_path", (
+    "../tools/car_model.obj",
+    "../ytyp/gizmos/models/AudioEmitter.obj",
+    "../ytyp/gizmos/models/AudioCollisionSettings.obj",
+    "../ytyp/gizmos/models/Buoyancy.obj",
+    "../ytyp/gizmos/models/Door.obj",
+    "../ytyp/gizmos/models/Expression.obj",
+    "../ytyp/gizmos/models/Ladder.obj",
+    "../ytyp/gizmos/models/LadderTop.obj",
+    "../ytyp/gizmos/models/LadderBottom.obj",
+    "../ytyp/gizmos/models/LightShaft.obj",
+    "../ytyp/gizmos/models/ParticleEffect.obj",
+    "../ytyp/gizmos/models/ProcObject.obj",
+    "../ytyp/gizmos/models/SpawnPoint.obj",
+    "../ytyp/gizmos/models/SpawnPointOverride.obj",
+    "../ytyp/gizmos/models/WindDisturbance.obj",
+))
+def test_obj_read_sollumz_builtin_asset(obj_relative_file_path: str):
+    obj_path = Path(__file__).parent.joinpath(obj_relative_file_path)
+    obj = obj_read_from_file(obj_path)
+
+    assert obj is not None
+    assert len(obj.vertices.flatten()) > 0
+    assert len(obj.indices.flatten()) > 0
+
+    obj_mesh = obj.as_bpy_mesh(obj_path.stem)
+    assert obj_mesh is not None
+
+    invalid_geom = obj_mesh.validate(verbose=True)
+    assert not invalid_geom
+
+    bpy.data.meshes.remove(obj_mesh)

tools/ymaphelper.py

@@ -1,7 +1,8 @@
 import bpy
-
+from pathlib import Path
 from ..sollumz_properties import SOLLUMZ_UI_NAMES, SollumType
 from ..tools.blenderhelper import find_bsdf_and_material_output
+from ..shared.obj_reader import obj_read_from_file
 
 # TODO: This is not a real flag calculation, definitely need to do better
 
@@ -70,3 +71,16 @@ def add_occluder_material(sollum_type=None):
     bsdf.inputs["Metallic"].default_value = 0
 
     return material
+
+
+CARGEN_MESH_NAME = ".sollumz.cargen_mesh"
+
+
+def get_cargen_mesh() -> bpy.types.Mesh:
+    mesh = bpy.data.meshes.get(CARGEN_MESH_NAME, None)
+    if mesh is None:
+        file_path = Path(__file__).parent.joinpath("car_model.obj")
+        cargen_obj_mesh = obj_read_from_file(file_path)
+        mesh = cargen_obj_mesh.as_bpy_mesh(CARGEN_MESH_NAME)
+
+    return mesh

ymap/operators.py

@@ -1,10 +1,7 @@
 import bpy
-import os
-
-from mathutils import Vector
 from ..sollumz_helper import SOLLUMZ_OT_base, set_object_collection
-from ..tools.ymaphelper import add_occluder_material, create_ymap, create_ymap_group
-from ..sollumz_properties import SOLLUMZ_UI_NAMES, SollumType
+from ..tools.ymaphelper import add_occluder_material, create_ymap, create_ymap_group, get_cargen_mesh
+from ..sollumz_properties import SollumType
 
 
 class SOLLUMZ_OT_create_ymap(SOLLUMZ_OT_base, bpy.types.Operator):
@@ -162,10 +159,8 @@ class SOLLUMZ_OT_create_car_generator(SOLLUMZ_OT_base, bpy.types.Operator):
 
     def run(self, context):
         group_obj = context.active_object
-        file_loc = os.path.join(os.path.dirname(__file__), "car_model.obj")
-        bpy.ops.import_scene.obj(filepath=file_loc)
-        cargen_obj = bpy.context.selected_objects[0]
-        cargen_obj.name = "Car Generator"
+        cargen_ref_mesh = get_cargen_mesh()
+        cargen_obj = bpy.data.objects.new("Car Generator", object_data=cargen_ref_mesh)
         cargen_obj.sollum_type = SollumType.YMAP_CAR_GENERATOR
         cargen_obj.ymap_cargen_properties.orient_x = 0.0
         cargen_obj.ymap_cargen_properties.orient_y = 0.0
@@ -178,7 +173,8 @@ def run(self, context):
         cargen_obj.ymap_cargen_properties.body_color_remap_4 = -1
         cargen_obj.ymap_cargen_properties.pop_group = ""
         cargen_obj.ymap_cargen_properties.livery = -1
+        bpy.context.collection.objects.link(cargen_obj)
         bpy.context.view_layer.objects.active = cargen_obj
         cargen_obj.parent = group_obj
 
-        return True
+        return True

ymap/ymapimport.py

@@ -1,12 +1,10 @@
 import binascii
 import struct
 import math
-import os
 import bpy
-
 from mathutils import Vector, Euler
 from ..sollumz_helper import duplicate_object_with_children, set_object_collection
-from ..tools.ymaphelper import add_occluder_material
+from ..tools.ymaphelper import add_occluder_material, get_cargen_mesh
 from ..sollumz_properties import SollumType
 from ..sollumz_preferences import get_import_settings
 from ..cwxml.ymap import CMapData, OccludeModel, YMAP
@@ -210,11 +208,10 @@ def cargen_to_obj(obj: bpy.types.Object, ymap: CMapData):
     bpy.context.collection.objects.link(group_obj)
     bpy.context.view_layer.objects.active = group_obj
 
-    cargen_ref_mesh = import_cargen_mesh()
+    cargen_ref_mesh = get_cargen_mesh()
 
     for cargen in ymap.car_generators:
-        cargen_obj = bpy.data.objects.new(
-            "Car Generator", object_data=cargen_ref_mesh)
+        cargen_obj = bpy.data.objects.new("Car Generator", object_data=cargen_ref_mesh)
         cargen_obj.ymap_cargen_properties.orient_x = cargen.orient_x
         cargen_obj.ymap_cargen_properties.orient_y = cargen.orient_y
         cargen_obj.ymap_cargen_properties.perpendicular_length = cargen.perpendicular_length
@@ -235,17 +232,6 @@ def cargen_to_obj(obj: bpy.types.Object, ymap: CMapData):
         cargen_obj.parent = group_obj
 
 
-def import_cargen_mesh() -> bpy.types.Mesh:
-    file_loc = os.path.join(os.path.dirname(__file__), "car_model.obj")
-    bpy.ops.import_scene.obj(filepath=file_loc)
-    cargen_ref_obj = bpy.context.selected_objects[0]
-    mesh = cargen_ref_obj.data
-
-    bpy.data.objects.remove(cargen_ref_obj)
-
-    return mesh
-
-
 def ymap_to_obj(ymap: CMapData):
     ymap_obj = bpy.data.objects.new(ymap.name, None)
     ymap_obj.sollum_type = SollumType.YMAP

ytyp/gizmos/extensions.py

@@ -1,13 +1,14 @@
 import bpy
 import math
-import os
 import functools
+from pathlib import Path
 from mathutils import Matrix, Vector, Quaternion
 from typing import Literal
 from collections.abc import Iterator
 from ..utils import get_selected_archetype, get_selected_extension, get_selected_ytyp
 from ...tools.blenderhelper import tag_redraw
 from ...sollumz_properties import ArchetypeType
+from ...shared.obj_reader import obj_read_from_file
 from ..properties.ytyp import ArchetypeProperties
 from ..properties.extensions import ExtensionType, ExtensionProperties
 
@@ -46,21 +47,9 @@ def get_extension_shapes() -> dict[ExtensionType, object]:
     shapes = {}
 
     def _load_extension_model(extension_type: ExtensionType, file_name: str):
-        file_loc = os.path.join(os.path.dirname(__file__), "models", file_name)
-        with open(file_loc, "r") as f:
-            verts = []
-            model_verts = []
-            for line in f.readlines():
-                if line.startswith("v"):
-                    x, y, z = line.strip("v ").split(" ")
-                    verts.append((float(x), float(y), float(z)))
-                elif line.startswith("f"):
-                    v0, v1, v2 = line.strip("f ").split(" ")
-                    model_verts.append(verts[int(v0) - 1])
-                    model_verts.append(verts[int(v1) - 1])
-                    model_verts.append(verts[int(v2) - 1])
-
-            shapes[extension_type] = bpy.types.Gizmo.new_custom_shape("TRIS", model_verts)
+        file_path = Path(__file__).parent.joinpath("models", file_name)
+        obj_mesh = obj_read_from_file(file_path)
+        shapes[extension_type] = bpy.types.Gizmo.new_custom_shape("TRIS", obj_mesh.as_vertices_only())
 
     for ext_type, model_file_name in (
         (ExtensionType.AUDIO_COLLISION, "AudioCollisionSettings.obj"),