ExportService

Overview

ExportService provides static methods for staging MPFB characters for export to external applications that do not support Blender-native features such as shape keys, modifiers, and armature-driven mesh deformation.

The typical workflow is:

• Create a deep copy of the character hierarchy with create_character_copy.
• Load facial animation targets (visemes, ARKit face units) onto the copy with FaceService.load_targets.
• Propagate those shape keys from the basemesh to child clothes and body proxy meshes with FaceService.interpolate_targets.
• Bake mask and subdivision modifiers—and optionally remove helper geometry—with bake_modifiers_remove_helpers.

All methods are static.

Viseme and face unit loading and interpolation is handled by FaceService. ExportService imports the facial animation constants (MICROSOFT_VISEMES, META_VISEMES, ARKIT_FACEUNITS, SIGNIFICANT_SHIFT_MINIMUM) from FaceService so that bake_modifiers_remove_helpers can identify which shape keys are facial-animation-related versus modelling targets.

Source

src/mpfb/services/exportservice.py

Dependencies

Dependency	Usage
LogService	Logging via LogService.get_logger("services.exportservice")
TargetService	Checking for shape keys, baking targets, and reapplying details
ObjectService	Duplicating objects, finding relatives, activating objects, and getting child lists
FaceService	Provides MICROSOFT_VISEMES, META_VISEMES, ARKIT_FACEUNITS, and SIGNIFICANT_SHIFT_MINIMUM constants

Public API

Character Copy

create_character_copy(source_object, name_suffix="_export_copy", place_in_collection=None)

Creates a deep copy of the character hierarchy, including any rig and all child meshes. The root object and every child get the name_suffix appended to their names. When the root is an armature, any Armature modifier on a duplicated child mesh is automatically re-pointed to the new armature so the copy is fully self-contained.

Argument	Type	Default	Description
source_object	bpy.types.Object	—	The source object to copy. Typically the basemesh or the rig. The basemesh is located via ObjectService.find_object_of_type_amongst_nearest_relatives.
name_suffix	str	"_export_copy"	Suffix appended to the name of every duplicated object
place_in_collection	bpy.types.Collection	None	Collection where duplicated objects are placed. If None, Blender's default collection is used.

Returns: bpy.types.Object — The root object of the duplicated hierarchy (the new rig if a rig is present, otherwise the new basemesh).

Raises: ValueError if no basemesh can be found among the nearest relatives of source_object.

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Modifier Baking

bake_modifiers_remove_helpers(basemesh, bake_masks=False, bake_subdiv=False, remove_helpers=True, also_proxy=True)

Bakes mask and subdivision modifiers into the mesh geometry and optionally removes helper/joint geometry. When the basemesh has shape keys, baking uses a copy-bake-apply-delta strategy (implemented in the private _apply_modifiers_keep_shapekeys method): for each shape key a temporary duplicate is created, modifiers are applied, and the resulting vertex deltas versus a modifier-applied Basis mesh become the new shape key data on the final mesh. This preserves all shape keys through modifier application. When no shape keys are present, modifiers are applied directly.

Subdivision modifier levels are set to render_levels before baking. Mask modifiers on the body vertex group (non-inverted) remove helper geometry from the mesh; if this removal is not baked, remove_helpers triggers a vertex-group-based deletion instead.

If also_proxy=True, the same mask and subdivision baking is applied to the body proxy mesh (if one exists), without the shape key preservation logic.

Argument	Type	Default	Description
basemesh	bpy.types.Object	—	The basemesh to operate on
bake_masks	bool	False	Apply mask modifiers into the mesh geometry
bake_subdiv	bool	False	Apply subdivision surface modifiers at render level
remove_helpers	bool	True	Delete HelperGeometry and JointCubes vertex groups and their geometry
also_proxy	bool	True	Also apply modifiers on the body proxy mesh, if present

Returns: None

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Examples

Full Export Pipeline

Create a complete export-ready copy with Microsoft visemes and modifier baking:

import bpy
from mpfb.services.exportservice import ExportService
from mpfb.services.faceservice import FaceService

# Assume `basemesh` is the selected MPFB basemesh
basemesh = bpy.context.active_object

# 1. Duplicate the full character hierarchy
export_root = ExportService.create_character_copy(
    basemesh,
    name_suffix="_export",
    place_in_collection=bpy.data.collections.get("Export")
)

# 2. Find the duplicated basemesh among the new root's children
from mpfb.services.objectservice import ObjectService
export_basemesh = ObjectService.find_object_of_type_amongst_nearest_relatives(export_root)

# 3. Load facial animation shape keys
FaceService.load_targets(
    export_basemesh,
    load_microsoft_visemes=True,
    load_meta_visemes=False,
    load_arkit_faceunits=True
)

# 4. Transfer shape keys from basemesh to clothes / proxy
FaceService.interpolate_targets(export_basemesh)

# 5. Bake modifiers and remove helper geometry
ExportService.bake_modifiers_remove_helpers(
    export_basemesh,
    bake_masks=True,
    bake_subdiv=True,
    remove_helpers=True,
    also_proxy=True
)

Minimal Copy Without Shape Keys

For a simple character with no facial animation requirements:

import bpy
from mpfb.services.exportservice import ExportService

basemesh = bpy.context.active_object

# Duplicate and immediately bake helpers away
export_root = ExportService.create_character_copy(basemesh, name_suffix="_game")

from mpfb.services.objectservice import ObjectService
export_basemesh = ObjectService.find_object_of_type_amongst_nearest_relatives(export_root)

ExportService.bake_modifiers_remove_helpers(
    export_basemesh,
    bake_masks=True,
    remove_helpers=True,
    also_proxy=False
)