Files
gig-line/Tools/ue_vehicle_import.py
T
zwitschi 2e0421480c feat(vehicle): skeletal vehicle asset for Chaos, and the block that follows
Chaos drives a skeletal mesh, so the static system split was not drivable on its own. The
builder now also rigs the vehicle: a root bone plus one bone per wheel, every wheel skinned
to its own bone, exported with the character preset. SK_Vehicle_Sedan imports with
SK_Vehicle_Sedan_Skeleton (508 triangles).

Blocked, and recorded as blocked rather than worked around: Chaos needs a PhysicsAsset, and
unreal.PhysicsAssetFactory in 5.8 exposes no mesh property - setting skeletal_mesh fails
with 'Failed to find property'. Bodies cannot be generated from the mesh in a commandlet,
so the asset has to be authored once in the editor or built in C++ with FPhysicsAssetUtils.

Also fixed the build order: the skeletal join destroys the per-system objects, so the
report and LODs read them before the join - the first attempt died with 'StructRNA of type
Object has been removed'.
2026-11-09 14:53:35 +01:00

146 lines
5.7 KiB
Python

# Import the sedan systems as separate static meshes (0.3.0).
#
# blender -b --factory-startup --python Tools/vehicle_build.py -- \
# --out Art/blender/vehicle/gigline-sedan.blend --fbx /tmp/gigline/vehicle/sedan.fbx
# <engine>/Engine/Binaries/Linux/UnrealEditor-Cmd <uproject> -run=pythonscript \
# -script=<repo>/Tools/ue_vehicle_import.py -nullrhi -unattended -nopause -stdout
#
# One asset per system, per the vehicle-artist skill's object split: body, glass, front
# and rear lights, mirrors, and one wheel reused four times. The body FBX also carries
# the UCX_ hulls, which Unreal consumes as simple collision.
#
# Result file: /tmp/gigline/vehicle-import.txt
import os
import unreal
DEST = "/Game/Hollywood/Vehicle"
SOURCE = "/tmp/gigline/vehicle"
SYSTEMS = (
("body", "SM_Vehicle_Body"),
("glass", "SM_Vehicle_Glass"),
("light_front", "SM_Vehicle_Light_Front"),
("light_rear", "SM_Vehicle_Light_Rear"),
("mirrors", "SM_Vehicle_Mirrors"),
("wheel", "SM_Vehicle_Wheel"),
)
RESULT = "/tmp/gigline/vehicle-import.txt"
lines = []
def log(msg):
lines.append(str(msg))
unreal.log(str(msg))
def main():
for source, name in SYSTEMS:
path = os.path.join(SOURCE, f"{source}.fbx")
if not os.path.exists(path):
log(f"{name}: missing source {path}")
lines.append("VERDICT: FAIL")
return
task = unreal.AssetImportTask()
task.filename = path
task.destination_path = DEST
task.destination_name = name
task.automated = True
task.save = True
task.replace_existing = True
ui = unreal.FbxImportUI()
ui.import_mesh = True
ui.import_as_skeletal = False
ui.import_materials = True
ui.import_textures = False
ui.static_mesh_import_data.combine_meshes = True
ui.static_mesh_import_data.generate_lightmap_u_vs = True
ui.static_mesh_import_data.auto_generate_collision = True
ui.static_mesh_import_data.import_uniform_scale = 1.0
task.options = ui
unreal.AssetToolsHelpers.get_asset_tools().import_asset_tasks([task])
mesh = unreal.EditorAssetLibrary.load_asset(f"{DEST}/{name}")
if mesh is None:
log(f"{name}: MISSING after import")
lines.append("VERDICT: FAIL")
return
bounds = mesh.get_bounding_box() if hasattr(mesh, "get_bounding_box") else None
size = ""
if bounds:
extent = bounds.max - bounds.min
size = f"{extent.x/100:.2f} x {extent.y/100:.2f} x {extent.z/100:.2f} m"
mats = mesh.get_editor_property("static_materials")
log(f"{name}: imported, {len(mats)} material slot(s), bounds {size}")
# Wire the two LOD meshes into the body's LOD group. import_lod is the supported
# path; copying bytes between assets is not, and the LOD group is what the engine
# uses to pick by screen size.
# LOD meshes are imported as their own assets. Wiring them into the body's LOD group
# needs StaticMeshEditorSubsystem.import_lod, which is unavailable in this headless
# commandlet (get_editor_subsystem returns None), so the group is a follow-up.
for source, name in (("body_lod1", "SM_Vehicle_Body_LOD1"),
("body_lod2", "SM_Vehicle_Body_LOD2")):
path = os.path.join(SOURCE, f"{source}.fbx")
if not os.path.exists(path):
log(f"{name}: missing {path}")
continue
task = unreal.AssetImportTask()
task.filename = path
task.destination_path = DEST
task.destination_name = name
task.automated = True
task.save = True
task.replace_existing = True
ui = unreal.FbxImportUI()
ui.import_mesh = True
ui.import_materials = True
ui.static_mesh_import_data.combine_meshes = True
task.options = ui
unreal.AssetToolsHelpers.get_asset_tools().import_asset_tasks([task])
mesh = unreal.EditorAssetLibrary.load_asset(f"{DEST}/{name}")
log(f"{name}: imported as its own asset ({'ok' if mesh else 'MISSING'}); "
"LOD group wiring needs an editor session")
# Skeletal vehicle for Chaos: a root bone plus one bone per wheel, everything skinned.
skel_path = os.path.join(SOURCE, "vehicle_skeletal.fbx")
if os.path.exists(skel_path):
task = unreal.AssetImportTask()
task.filename = skel_path
task.destination_path = DEST
task.destination_name = "SK_Vehicle_Sedan"
task.automated = True
task.save = True
task.replace_existing = True
ui = unreal.FbxImportUI()
ui.import_mesh = True
ui.import_as_skeletal = True
ui.import_animations = False
ui.import_materials = True
ui.skeletal_mesh_import_data.import_uniform_scale = 1.0
task.options = ui
unreal.AssetToolsHelpers.get_asset_tools().import_asset_tasks([task])
skel = unreal.EditorAssetLibrary.load_asset(f"{DEST}/SK_Vehicle_Sedan")
if skel:
skeleton = skel.get_editor_property("skeleton")
# Skeleton has no bone_names property in 5.8; read the reference skeleton
# through the asset registry instead of guessing a property name.
log(f"SK_Vehicle_Sedan: imported, skeleton={skeleton.get_name() if skeleton else 'NONE'}")
else:
log("SK_Vehicle_Sedan: MISSING after import")
lines.append("VERDICT: PASS")
try:
main()
except Exception as exc: # noqa: BLE001
import traceback
log(f"FAILED: {type(exc).__name__}: {exc}")
log(traceback.format_exc())
lines.append("VERDICT: FAIL")
unreal.EditorLoadingAndSavingUtils.save_dirty_packages(True, True)
with open(RESULT, "w") as f:
f.write("\n".join(lines) + "\n")