Alembic Export Options

Alembic Export Patterns

Pattern 1 — Named preset (recommended)

from os_fast_ref.api import FastRefAPI

api = FastRefAPI()
api.export_abc(slot=0, output_path=r"J:\output\char.abc", preset="Unreal_UE5")
api.export_abc_all(output_folder=r"J:\output", preset="Unity_ABC")

A non-existent preset name immediately raises ValueError.

Bundled presets: Unreal_UE5, Unity_ABC

Pattern 2 — Export Type filter (Meshes / Bones)

Applied just before the final select, after candidate collect (Auto Skin / Defined Selection Set).

from os_fast_ref.api import FastRefAPI

api = FastRefAPI()

# Meshes only (typical UE Geometry Cache)
api.export_abc(
    slot=0,
    output_path=r"J:\output\char_mesh.abc",
    preset="Unreal_UE5",
    abc_options={"ExportMeshes": True, "ExportBones": False},
)

# Bones only
api.export_abc(
    slot=0,
    output_path=r"J:\output\char_bones.abc",
    abc_options={"ExportMeshes": False, "ExportBones": True},
)

Both False → FAIL FAST. Defaults are both True.

Reset Root: Independent of Export Type. Full bone list is used to reset Root PRS first, then only filtered nodes are exported.

Pattern 3 — Copy defaults then modify

from os_fast_ref.api import FastRefAPI

api = FastRefAPI()
defaults = api.get_abc_default_options()
opts = defaults["options"].copy()
opts["ExportBones"] = False
opts["RemoveNameSpace"] = True
opts["ResetRoot"] = True
api.export_abc(slot=0, output_path=r"J:\output\char.abc", abc_options=opts)

Pattern 4 — preset + partial override

from os_fast_ref.api import FastRefAPI

api = FastRefAPI()
api.export_abc(
    slot=0,
    output_path=r"J:\output\char.abc",
    preset="Unreal_UE5",
    abc_options={
        "ExportMeshes": True,
        "ExportBones": False,
        "CoordinateSystem": "yup",
    },
)

Pattern 5 — Defined Selection Set

If the reference INFO has fbxExportMode == "Defined" and fbxExportSelectionSets,
ABC splits output files per Selection Set the same way as FBX.

• 1 set → {base}.abc
• 2+ sets → {base}_{SetName}.abc

Export Type filtering is applied again to each set's nodes.

# Selection Sets come from Rig Data Manager / INFO
# Just call export_abc — Defined path is taken automatically
api.export_abc(slot=0, output_path=r"J:\output\char.abc", preset="Unreal_UE5")

Key Alembic Options Reference

Lookup:

info = api.get_abc_default_options()
print(info["preset_name"])
print(info["options"].keys())