About ArtMesh

(Updated 07/06/2020)

On this page you will learn about ArtMesh.
In Cubism 2.1, they were called “drawing objects”.


What is ArtMesh?

PSD images loaded into the model workspace are automatically assigned a mesh for each layer and placed on the canvas.
Each of these is an “ArtMesh”.

In the image below, a set of polygons (mesh) composed of vertices and lines is assigned to the eyebrow image (texture).
By moving each of these vertices, the image can be deformed to create expression and movement.

Upon importing a PSD, each layer (or group) in the PSD is automatically placed as an ArtMesh, but
if all meshes are too detailed, the data volume will be too large.

Thus, immediately after placement, the ArtMesh consists of a minimum number of vertices.
* However, when using video works that do not use the SDK, there is no need to be aware of the data capacity, as it does not affect the data volume.

These initial ArtMeshes can be further edited in detail to suit the image you wish to deform.
See the “Mesh Editing” page for more information on how to edit the mesh in detail.


Blend Mode

You can specify how the colors of the ArtMesh are composited.
The default setting is [Normal].

Normal Additive Multiply
The image cut from the texture is overlapped as is. Suitable for glowing expressions. It is suitable for expressions with darker colors, such as shadows.



Culling is the ability to not draw the backside of polygons.
The default setting is [Off].


On (single-sided drawing)
Polygons are not drawn when flipped over.
Off (double-sided drawing)
It is drawn regardless of the reverse side.

Turn on if you want the part to disappear when the polygon is flipped over.
Turn off when you want to create a part with polygons flipped over and left to right.


How to calculate triangulation

The triangulation calculation method has been changed since Cubism 3.0.07.


Polygon => Triangle auto-transform (auto-connect edges)

Both Cubism 2.1 and 3.0 or later have a mechanism to convert a polygon (square or larger) or unconnected points into a triangle by connecting them.
This allows us to draw at high speed using 3D hardware.

The light blue area in the figure is an automatic connection

Cubism 2.1 calculation scheme:
2.1 uses a very simple method of connection, whereby squares and other objects are triangulated without consideration of angles.
The calculations were such that the connection was made in a shape that exceeded a pentagon and was not very appropriate.

Calculation method in Cubism 3.0 or later:
3.0 and later, the structure has been changed to generate triangles as naturally as possible, even for polygons beyond the pentagon and in situations where the points are not well connected.
* The system was buggy until 3.0.06, but has become significantly more stable since 3.0.07.


For models generated from 2.1 cmox

Before 3.0.06:

  • When loading the .cmox file created in 2.1, the process of creating triangles was being executed using the calculation method for 3.0.
    (However, due to differences in calculation methods between 2.1<>3.0 and a bug up to 3.0.06, some meshes loaded from 2.1 were missing.)

S3.0.07 or later:

  • To ensure that models created in 2.1 can be safely used in the SDK for 3.0 without modification, the .cmox file is now triangulated on Cubism 3.0 using the same calculation method as in 2.1 when loaded.
  • On 3.0, the calculation method for 2.1 works as long as no mesh editing (automatic or manual) is performed on each ArtMesh. The moc3 , moc has been changed so that it can be safely used with the same results as 2.1 by writing moc3 , moc as is.
  • The system is designed to switch to the 3.0 off-style triangulation process once the mesh editing (automatic or manual) of each ArtMesh is performed on the 3.0.
  • 3.0.07 fixes a bug that occurred prior to 3.0.06 and improves the connection to be cleaner and safer.


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