Retargeting Overview — Natural Motion Across Different Character Skeletons

Custom characters often have different bone hierarchies and skeleton proportions compared to MOVINMan. If you use them as-is, their movement may look unnatural: different arm lengths, shorter spines, or irregular bone structures all affect motion.

MOVIN Studio adjusts these differences so that:

the meaning of the motion (walking, running, crouching) stays the same,
rotation, length, and position are adapted to each character’s proportions, and
the final result stays close to the original motion.

The retargeting process has four main steps:

Pose Matching — Align Rest Pose and basic structure
Bone Mapping — Set 1:1 bone relationships
Retargeting Settings — Fine-tune the motion behavior
Bone Offset — Make final detailed adjustments

1. Pose Matching — Matching the Character’s Rest Post to MOVINMan

Pose Matching is the first step of retargeting and ensures that both the character and MOVINMan share the same base pose for the process.

T-Pose alignment — Mirror Mode lets you adjust both sides at the same time.

This step includes:

Adjusting the character’s Rest Pose
Fixing mismatches in the bone hierarchy
Removing initial errors caused by pose differences

The precision of this stage directly affects the accuracy of both Bone Mapping and Retargeting Settings.

2. Bone Mapping — Accurate Mapping Creates Natural Motion

Bone mapping is the process of matching each source skeleton joint to the corresponding target character joint so motion can be transferred accurately and naturally.

Setting Up Chains — Structuring the Character’s Joints

In MOVIN Studio, a character’s bones are organized into multiple Chains. A Chain is the basic unit used during retargeting and helps you understand the joint structure and map the bones in the correct order.

Setting Up Chains — Select a chain and add the required bones to define the character’s structure.

Bone Flag — Defining the Role of Each Bone

After setting up the Chains, you need to assign Bone Flags so MOVIN Studio can correctly understand the role of each bone. This is an important step that directly affects the quality of the retargeting result.

Setting Up Bone Flags — Assign roles such as IKStart and IKEnd to specific bones within each chain.

Rotational Mapping — Controlling How Rotation is Transferred

Rotational Mapping defines which MOVINMan bone each bone in the selected chain should follow for rotation. When your character’s bone structure does not perfectly match MOVINMan’s, some bones may sit between two source bones (A and B). In this case, Rotational Mapping lets the bone blend the rotation of A and B, creating a smooth and natural rotation that fits its position. This helps maintain stable and natural movement even for characters with different skeletal structures.

Rotational Mapping — Auto Setting considers bone length, chain structure, and Bone Flags.

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MOVINStudio Auto Setting

The Auto Setting feature creates Rotational Mapping automatically based on:

Bone length
Defined chain structure
Bone Flag information

It’s useful for quickly generating a basic mapping, which you can then refine by adjusting only the parts that need more detail.

3. Retargeting Settings — The Key Step for Preserving Motion Meaning

Retargeting Settings is the area that received the biggest improvements in this update. By adjusting a wide range of options for three body parts—Body(Root)Arm, and Leg—you can make your character’s movement look much more natural.

Three Retargeting Categories

Root Retargeting

Controls the position, movement, and rotation of the Hip bone (the first bone in the spine chain)

Leg Retargeting

Reduces foot sliding
Keeps the foot end effector stable on the ground

Arm Retargeting

Adjusts hand position
Prevents arms, hands, and fingers from intersecting with the character’s body
Controls natural arm movement using features like Z Mapping and X-dir Shift
Adjusts finger retargeting behavior

Each feature behaves differently depending on the character’s proportions and bone structure. Reviewing these options together with visual examples will help you understand how the motion is corrected. The sections below explain each major feature with examples.

How Each Retargeting Option Works (with MOVIN Studio)

Root Retargeting — adjust the Character’s position & rotation to match the MOVINMan

Retarget Translation & Offset

This option defines how much of the source MOVINMan’s root(hip) movement is passed to the character. Higher values keep the character’s stride closer to the original motion, while lower values reduce the overall movement, resulting in a smaller and more contained motion.

Retarget Translation — Adjusts how much of the MOVINMan’s movement is applied to the character.

Retarget Rotation & Offset

This option controls how strongly the source hip rotation is applied. Higher values closely follow the original rotation, while lower values produce smoother and softer turns.

Retarget Rotation — Adjusts how much of the MOVIN Man’s rotation is applied to the character.

You can also apply additional Translation Offsets to fine-tune the character’s center position or starting point.

Retarget Offset — Adjusts the character’s reference position along the X, Y, and Z axes.

Rotational Offset — Adjusts the Hip bone’s rotation around the X, Y, and Z axes.

Leg Retargeting — Ensures stable, grounded foot alignment

Leg Retargeting focuses mainly on vertical correction to prevent feet from sinking below or hovering above the ground. It also helps reduce foot sliding and maintains stable contact during walking and running.

Most key options used here (Enable IK, Minimum Chain Stretch, Minimum End Effector Y, Penetration Resolve Mode, Enable End Effector Mapping) are also shared with Arm Retargeting, helping stabilize upper-body behavior as well.

Enable IK More Natural Motion Based on Foot/Hand Position

When IK is enabled, the system locks the foot or hand position first, then adjusts the other joints automatically. This prevents excessive bending caused by differences in body proportions.

Enable IK — Applies more natural joint corrections based on the end effector.

Minimum Chain Stretch Preventing unnatural over-bending of limbs

This sets how short a chain (leg/arm) is allowed to become. This setting defines how short the chain distance between the IKStartBone and IKEndBone can become relative to its original Rest Pose length (1.0).

Minimum Chain Stretch — Prevents the chain from becoming unnaturally short, avoiding abnormal joint collapsing.

Minimum End Effector Y Minimum Allowed Height

This prevents the IKEnd Effector(hand or foot) from going below a defined vertical point. It helps avoid “sinking” during jumps, landings, or quick movements.

Penetration Resolve Mode Prevents Resolving body-ground penetration

This option resolves situations where limbs intersect the ground or the character’s own body.

Modes include:

None — No correction applied.
Push Root — Moves the Hip bone upward along the Y-axis to resolve the issue.
Push Limb — Projects the IKEndBone upward along the Y-axis and bends the limb to adjust the pose.

This greatly improves overall stability by preventing unnatural poses.

Penetration Resolve Mode — Prevents body-ground penetration for stable grounding

Arm Retargeting (Enable end effector) - More Natural Arm and Hand Motion

Arm motion can vary significantly depending on the character’s proportions, so fine-tuning is essential. Among the available options, Enable End Effector Mapping plays a key role in stabilizing the hand’s position and overall trajectory.

Since the previous Root Retargeting and Leg Retargeting sections already covered the key functionalities and shared options, the following section will focus on Arm Retargeting’s distinctive feature: Enable End Effector Mapping.

X Mapping Adjusts the X-axis position of the IKEndBone to match the hand’s relative position to both shoulders, as in MOVINMan.

X Mapping — Adjusts the hand’s left–right position relative to the shoulders for a more natural alignment.

Z Mapping (Head / Body) Applies natural forward/backward adjustments to the hands when raising or lowering the arms.

Z Mapping: Controls the base amount of forward/backward movement.
Z Mapping Pow: Controls how sharp or smooth the adjustment curve is (higher values produce stronger changes).

Z Mapping (Head) — Adjusts the hand’s natural forward movement when raising the arm.

Z Mapping (Body) — Adjusts the hand’s natural backward movement when lowering the arm.

X-dir Shift(Head/Body) Adjusts how much the hands move inward or outward depending on arm height.

X-dir Shift (Head) — Naturally moves the hands outward when raising the arms.

X-dir Shift (Body) — Naturally draws the hands inward toward the torso when lowering the arms.

Additional tools for refining finger motion are also included in the Arm Retargeting system.

FK Thumb Scale Prevents unnatural bending by adjusting the thumb’s rotation intensity, compensating for differences in character hand proportions

Thumb FK Scale — Adjusts the thumb’s rotation strength to create natural thumb motion for custom characters.

MOVIN Studio offers many more retargeting options for achieving higher-quality motion results.

Detailed explanations and step-by-step examples are available at

MOVIN | MOVIN Docs

4. Bone Offset — Final Fine-tuning Stage

Once the overall motion has been aligned using Retargeting Settings, Bone Offset allows you to apply additional adjustments to specific bones such as the spine, shoulders, thighs, and head to refine the character’s posture and overall feel.

Bone Offset — Apply additional offsets to individual bones for precise pose refinement.

Bone Offset is the final stage of retargeting and allows animators to fine-tune a character’s pose while preserving the original Rest Pose, making it extremely useful for detailed styling.

Utility Tools — MOVINMan Poser & Clip Player

To preview and fine-tune retargeting results, MOVIN Studio provides two additional tools:

MOVINMan Poser

This tool allows you to directly adjust the MOVINMan’s pose using per-joint controllers. Each foot joint includes a green controller that you can drag to modify the foot’s direction and rotation. The blue marker indicates the pivot point for that joint.

MOVINMan Poser — Adjust the MOVINMan’s joints directly using gizmos.

For hand joints, a triangular gizmo is displayed, allowing you to control finger direction and rotation relative to the wrist and fingers.

MOVINMan Poser — Hand joint controller.

Clip Player

Clip Player lets you preview retargeting results using recorded motion clips. While a clip is playing, you can pause at any specific pose and adjust the retargeting options based on that frame, allowing for precise tuning.

Clip Player — Review retargeting results through recorded clips.

By using MOVINMan Poser and Clip Player together, you can efficiently refine retargeting settings to achieve natural motion across any pose or movement.

Final Thoughts

MOVIN Studio’s retargeting system is more than just a feature that “supports the use of custom characters.” It is a precise correction tool designed to preserve each character’s unique style and structure while producing natural motion.

This update focuses on improving the retargeting process—which typically takes the most time in the motion pipeline—to make it faster, more accurate, and more intuitive.

For detailed option descriptions and step-by-step guides, please visit MOVIN Docs.

If you have any questions while using MOVIN Studio, feel free to reach out anytime on our MOVIN Discord channel.

MOVIN Studio v2.0 — Retargeting System Update for more natural motion