About Cubism Viewer (for OW)

Updated: 08/26/2025

Cubism Viewer (for OW) is a Viewer intended only for validation of data created with Cubism.
Note: OW stands for “Original Workflow.”

With Cubism Viewer (for OW), you can check the following model display playback, etc.
• Physics
• Eye tracking
• Playback of multiple motions
• Facial expression settings
• Pose settings

Models and motions that can be loaded in Cubism Viewer are data exported for embedded use.
Please note that .cmo3 and .can3 for editing cannot be loaded.

About the Screen of Cubism Viewer (for OW)

Number	Item	Details
(1)	Menu area	A menu appears that allows you to load models, manipulate parameters, and play back motion. The menu to be displayed is selected from the drop-down at the top.
(2)	Resource area	Display the loaded data and data created in Cubism Viewer.
(3)	Setting item area	Change and check settings related to expression setting files and motion files. The settings can be saved in a model settings file. [File] menu -> [Export] -> [Model Settings (model3.json)]
(4)	Model display area	The loaded model is displayed here. The model can be moved or scaled. The [Show] menu allows you to change the background color, display the model with a transparent background, and display the collision detection. Note: The alpha value (transparency) of the background color cannot be set in the macOS version.

How to Start Cubism Viewer (for OW)

Cubism Viewer (for OW) is included in the Cubism Editor installer.
After extracting the file, start the CubismViewer.exe file, which is located in the same folder hierarchy as the executable file.

File Loading

Upon activation, a dialog box for loading opens.
Drag and drop the “.moc3” or “.model3.json” file to start the Viewer.

Language Settings

You can switch the display language from the [File] menu -> [Language]. 

The following are the specifications for language settings.

• The language will be switched when the Editor is restarted after changing the setting.
• Language settings are shared within Editors of the same minor version (e.g., 5 series).
• Language switching, which is done through the Editor’s [Settings] menu, takes precedence over the installation settings and OS settings.

Color Theme

You can also switch between the [Light] and [Dark] color themes from [File] menu -> [Color theme].

How to Create Basic Embedded Data

(1) Execute MOC3 file export from modeling

[File to be exported]
　• Texture file (.png)
　• MOC3 file (.moc3)
　• Model file (.model3.json)
　Note: Includes links to physics settings (.physics3.json) and motion-sync settings (.motionsync3.json).

(2) “Export motion file” from Animation

[File to be exported]
　• Motion file (.motion3.json)

(3)Load the following files into the Viewer

　• MOC3 file (.moc3)  Note: .model3.json is also acceptable
　　=> File is loaded and the Viewer starts up
　• Exported motion (.motion3.json) file

(4)Configure settings in the Viewer

　• Pose settings (.pose3.json)
　• Expression settings (.exp3.json)
[Notes]
　　Files set in Viewer are marked with an asterisk to the upper right of their names.

(5)Exporting Model Setting Files

　• Model settings file (.model3.json)
[Notes]
　　When you overwrite the (.model3.json) output from Cubism Editor at output, the file created by Viewer (marked with an asterisk) will be saved together.

Menu of Cubism Viewer (for OW)

File

Item	Details
Add	Expression: Add motion for facial expressions. In the setting item area, place a check mark next to the parameter for which you want to set the expression and adjust the parameter. Pose: Create a settings file in JSON format to reflect the arm switching mechanism created in the model and motion. See the “Pose Settings” page for detailed instructions.
Import	Motion for facial expressions (motion3.json/exp3.json): Load [.motion3.json] for facial expressions exported in the animation process into Cubism Viewer.
Export	Model settings (model3.json): Export the settings made in Cubism Viewer in a JSON format file. Shortcut key [Ctrl] + [S] All facial expression motions: Export all facial expression motions as JSON format files. See the “Expression Settings and Export” page for a detailed explanation. Pose: Export the pose switching settings in a JSON format settings file. See the “Pose Settings” page for a detailed explanation.
Settings	Include the extension in the default expression name: Include the extension in the default expression name when adding an expression. Open destination location after saving and exporting: If unchecked, the destination folder will not open after saving or exporting.

Edit

Item	Details
Restore parameters to default values	Reset parameters to default values.
Stopping motion	Stops the motion being played.
Difference Comparison	Information from two MOC3 data files can be compared and checked in the Viewer. See the “Comparison of two MOC3 data information files” page for details.

Show

Item	Details
Display of collision detection	Displays the set collision detection.
Enable mipmap	Enable mipmap. Note: Typically, we recommend that you check the box.
Background transparency (beta)	Displays the model with a transparent background. Note: This feature is not available in the macOS version.
Background color setting	Sets the background color. Note: The alpha value (transparency) cannot be set in the macOS version.
Frame rate display	The frame rate is displayed in the upper right corner of the model display area.
Show events	The event is displayed in the lower right corner of the model display area.

Animation

Item	Details
Enable facial expressions	Enables playback of motion for facial expressions.
Automatic Eye-blinking	Make the eyes blink automatically.
Enable Physics	Enable physics settings.
Enable Pose Switching	Enable Pose Switching.
Motion Sync	Enable motion-sync. See “Motion-sync Settings (OW)” for details.
Idle Motion	Enables idle motion.
Cursor tracking	Enables cursor tracking in the model display area.
Breath	Enable breathing. Breath applies values to parameters whose parameter IDs are “PARAM_BREATH” or “ParamBreath.”
Parameter Repeat	Enable Parameter Repeat.
Use Old Motion Playback Method	Enable the old motion playback method.  The [Use Old Motion Playback Method] checkbox in the lower right corner of the model display area is checked. See the “When the reproducibility of motion3.json deteriorates” page for a detailed explanation.
Use the old fading method	Enable the old fading playback method for expressions.  The [Use the old fading method] checkbox in the lower right corner of the model display area is checked. For a detailed explanation, please see the “Fixing Bugs with Expression Transition Processing in Cubism 5 or Later” page.
Cursor tracking settings	Opens a dialog box for cursor tracking settings.

About Cubism Viewer (for OW) Features

Cursor tracking settings

Check [Animation] menu -> [Follow Cursor] and drag on the View to move the model following the mouse cursor.
You can also set the parameters you want to follow in the [Animation] menu -> [Cursor Tracking Settings], which allows you to simulate the actual device.

Impact (%):
The degree of influence can be set to affect the movement of the parameter.
A stronger setting will result in a larger movement, while a weaker setting will result in a smaller movement.

Reflect:
The cursor tracking is inverted.

Type:
Set the type of parameter you want the cursor to follow.
• In the case of left mouse dragging
(Left mouse X: horizontal movement, Left mouse Y: vertical movement)

• In the case of right mouse dragging
(Right mouse X: horizontal movement, Left mouse Y: vertical movement)

Cursor tracking settings are saved in the model data (.cmo3) but are not exported to the embedded data.
If you want the cursor to follow when embedding, configure the settings on the SDK side.

Note: Cursor tracking settings can also be checked in “Physics Settings.”

MOC3 File Information List

Click on the MOC3 file name to check the following information from the dropdown menu below.

• Parameters
• Parts
• Art Mesh
• Offscreen Rendering
• Draw Order
• Statistics

In the items Art Mesh, Offscreen Rendering, and Draw Order, you can view information such as the number of polygons and vertices in a list format.

Art Mesh

When selected individually from the list, the target art mesh will blink blue in the viewer.

Statistics

You can check information such as the target version from the MOC3 file’s statistics.

About Curve Lines

Image confirmation of curves

Select motion3.json and click “View Motion Changes in Image” from the right-click menu to view the curve in an image.

Displaying motion curve type

The motion inspector in the [OW Viewer] now displays the target version inferred from the information contained in the motion.

If you are using “SDK (Others)” in the target version, please consult with the developer and consider whether to check the box.
See the “When the reproducibility of motion3.json deteriorates” page in the SDK Manual for details.

Waveform comparison

For motions exported with the [SDK (Others)] function for checking curves, curves that are played back with unsupported SDKs are now displayed in light blue.

Use Old Motion Playback Method

In Cubism Viewer (for OW) versions before 4.1, any motion file was reproduced using the same curves as in the Cubism Editor animations.
From version 4.1 onward, Cubism Viewer (for OW) reproduces motions using the curves played back by the SDK.
To use the curves from before 4.1, check the option “Use old motion playback method.”

With the “Use Old Motion Playback Method” checked, the motion is played back with the Bezier curve motion with the Bezier handle fixed at 1/3 or 2/3.

If you are using the SDK (Others) in the target version, please consult with the developer and consider whether to check the box.
See the “When the reproducibility of motion3.json deteriorates” page in the [Cubism SDK Manual] for more details.

Comparison of two MOC3 data information files

Information from two MOC3 data files can be compared and checked in the Viewer.

The confirmation procedure is as follows:

1. Drag and drop the two data files you want to compare into the Viewer
2. Click [Edit] menu -> Select [Compare Difference]
3. Check the confirmation dialog box that appears

(1) File information

Display the information of the file you want to compare, such as the file name, the date/time the file was created, and the location of the file.

(2) Categories and detailed items

Canvas:
Display the comparative information on the canvas.

Parts:
Display the comparative information on parts.

Parameter:
Min, Default, and Max values are compared and displayed for each ID.

ArtMesh:
Information on the following items for each ID is displayed for comparison.

1. Blend Mode
2. Culling
3. Texture number
4. Draw order
5. Draw order of Artmesh
6. Mask
7. Number of vertices
8. Number of polygons

Burning eye blinking and lip-sync motion

Motion set in “Eye blinking” and “Lip-sync” can be burned (baked) into Live2D parameters when exporting motion.
Since “Scale” and “Effect” data are not exported to motion3.json, this feature can be used to completely reproduce the motion of an animation in the Viewer.

Note, however, that the motion3.json file must be written out again if adjustments are necessary.
Note: When using Viewer (for OW), burning the motion function for eye blinking and lip-sync is recommended.

When setting motion data, check the “Burn Lip-sync and Blink into Motion” checkbox.
How to burn motion:

If this item is enabled, “Lip-sync” and “Eye blinking” will not be exported to motion3.json separately, so the items will be grayed out.

In this state, clicking “OK” will burn the motion as keyframes on the parameters checked in the Settings for Eye Blinking and Lip-sync, and will output as motion3.json.

If a keyframe is set for the parameter to which “Eye blinking” or “Lip-sync” is applied, the curve of the above effect is calculated (multiplied in the case of eye blinking, added in the case of Lip-sync) for that parameter.