Operations

Source: src/mpfb/ui/operations/animops/

Parent panel: MPFB_PT_Operations_Panel ("Operations")

Overview

The "Animation" panel provides tools for working with animation on MPFB characters, with a focus on Mixamo integration. Mixamo is an Adobe online service that offers automatic character rigging and a library of pre-made animations. The typical workflow for using Mixamo animations with an MPFB character involves:

1. Creating a reduced copy of the character (using Mixamo reduced doll) and uploading it to Mixamo.
2. Downloading the Mixamo animation on a Mixamo rig.
3. Importing the Mixamo rig and animation into Blender alongside the MPFB character.
4. Mapping the Mixamo animation onto the MPFB rig (using Snap to mixamo).
5. Optionally making the animation loop (using Make cyclic) or repeating it over time (using Repeat animation).

The panel is only drawn when an active object exists. The Mixamo mapping and cyclic/repeat operators additionally require the active object to be an armature.

Panel

MPFB_PT_AnimopsPanel ("Animation")

Attribute	Value
bl_label	"Animation"
bl_category	OPERATIONSCATEGORY
bl_parent_id	MPFB_PT_Operations_Panel
bl_options	{'DEFAULT_CLOSED'}
Base class	Abstract_Panel
Properties prefix	"ANIO_"

The panel draws four collapsible boxes when the relevant conditions are met:

• Reduced doll — always shown when an active object exists. Contains the call_fbx toggle and the Mixamo reduced doll button.
• Map mixamo — shown when the active object is an armature and exactly two armatures are selected. Displays the auto-detected source and destination rig names and the Snap to mixamo button.
• Make cyclic — shown when the active object is an armature. Contains the shiftroot toggle and, if enabled, the rootbone field, plus the Make cyclic button.
• Repeat animation — shown when the active object is an armature. Contains iterations, offset, skipfirst, shiftroot, and (if shiftroot is enabled) firstframe and rootbone fields, plus the Repeat animation button.

Operators

MPFB_OT_Reduced_Doll_Operator

Attribute	Value
bl_idname	mpfb.reduced_doll
bl_label	"Mixamo reduced doll"
bl_options	{'REGISTER', 'UNDO'}
Poll	ANY_MAKEHUMAN_OBJECT_ACTIVE

Creates a stripped-down copy of the character suitable for upload to Mixamo. The character must have a basemesh parented to a rig.

The operator duplicates the rig and basemesh, removes all modifiers from the basemesh copy except the armature modifier (which is relinked to the new skeleton), and then calls mpfb.delete_helpers and mpfb.bake_shapekeys on the copy to produce a clean, game-ready mesh. The resulting pair of objects is named <original>_reduced and <original>_body_reduced.

If the call_fbx scene property is enabled, the Blender FBX export dialog is opened automatically after the copy is created, with only the new objects selected. This lets you export and upload to Mixamo in one step.

A warning is issued if the rig is not a Mixamo-type rig, since Mixamo expects its own skeleton format.

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MPFB_OT_Map_Mixamo_Operator

Attribute	Value
bl_idname	mpfb.map_mixamo
bl_label	"Snap to mixamo"
bl_options	{'REGISTER', 'UNDO'}
Poll	Exactly two armatures must be selected

Maps a Mixamo animation from a source rig onto a destination rig by adding bone constraints. Both selected armatures must be Mixamo rigs (their bone names must contain a mixamorig: prefix).

The operator automatically determines which rig is the source (the one without an MPFB basemesh among its relatives) and which is the destination (the one with a basemesh). If both or neither has a basemesh, the active object is treated as the destination.

For each bone in the destination rig, a COPY_ROTATION constraint is added pointing to the matching bone in the source rig. A COPY_LOCATION constraint is additionally added to the hip bone so the root motion is also transferred. If the rigs do not have identical bone sets, a warning is issued but the operation proceeds for the bones that do match.

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MPFB_OT_Make_Cyclic_Operator

Attribute	Value
bl_idname	mpfb.make_cyclic
bl_label	"Make cyclic"
bl_options	{'REGISTER', 'UNDO'}
Poll	ANY_ARMATURE_OBJECT_ACTIVE

Makes the current animation loop seamlessly by adding an F-Curve Cycles modifier to every F-curve on the armature. This calls AnimationService.make_cyclic().

If shiftroot is enabled and a rootbone name is specified, the root bone's translation will be adjusted when the cycle loops so the character continues to move forward rather than snapping back to the origin. This is useful for walk cycles where the hips translate over time.

Warning: This operator fails silently if any F-curves already have modifiers applied to them. Always apply this to a clean animation without pre-existing F-curve modifiers.

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MPFB_OT_Repeat_Animation_Operator

Attribute	Value
bl_idname	mpfb.repeat_animation
bl_label	"Repeat animation"
bl_options	{'REGISTER', 'UNDO'}
Poll	ANY_ARMATURE_OBJECT_ACTIVE

Experimental. Duplicates the entire animation iterations times, appending each copy at the end of the previous one and optionally offsetting the root bone's position so the character continues moving in the same direction.

The operator calculates the total displacement of the root bone (identified by the rootbone property, typically mixamorig:Hips) over the animation and shifts each repeated copy by a corresponding multiple of that distance. The offset property adds an extra frame gap between repetitions, and skipfirst skips the first keyframe of each repeated copy (useful when the first and last frames are identical in a looping animation).

If a simple seamless loop is all you need, Make cyclic (above) is the better choice. Repeat animation is intended for cases where you want a finite, editable timeline with explicit repeated copies.

Scene Properties

Properties are stored with the ANIO_ prefix on the scene object.

Property	Type	Default	Description
call_fbx	boolean	—	Open the FBX export dialog after creating the reduced doll
shiftroot	boolean	—	Shift root bone position when cycling or repeating
rootbone	string	—	Name of the root/hip bone to use for root motion calculations
iterations	int	10	Number of times to repeat the animation
offset	int	—	Extra frame gap between repeated copies
skipfirst	boolean	—	Skip the first keyframe of each repeated copy
firstframe	int	—	First frame index to use when repeating with root shift

Related

• Operations index
• UI Layer overview
• Meta classes