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Manual - Blender 2.48

[edit] Mask Modifier

[edit] Description

The Mask Modifier allows certain parts of an objects mesh to be hidden from view (Masked off), in effect making the parts of the mesh that are masked act as if they were no longer there.

Cube before a Mask Modifier is added to the Cube.

The same Cube with the Mask Modifier added with assigned vertex groups.

The screenshots above show a cube before and after a Mask Modifier is added to it. In the second screenshot the cube has had parts of its mesh assigned to a vertex group which the Mask modifier uses to determine which parts will be visible and which parts wont.

[edit] Options

Below is a screenshot of the Mask Modifier panel and some of its options:

Screenshot showing the Mask Modifier panel settings.

• Vertex Group:

When the Mask Modifier is used it must be told which parts of a mesh are to be affected by the Mask Modifier. There are a few ways to do this, but when the Vertex Group option is selected the Mask Modifier uses a specified Vertex Group to determine which parts of a mesh are Masked by the modifier.

Screenshot showing the Mask Modifier panel settings with the Vertex Group option highlighted in yellow.

• VGroup:

When the Vertex Group selection option for masking is used the VGroup field becomes visible.

Screenshot showing the Mask Modifier panel settings with the VGroup option highlighted in yellow.

In the VGroup: field enter the name of a vertex group that is associated with the current mesh. When this is done the Mask Modifier will update so that anywhere the vertices of the mesh are part of the named vertex group will be masked (which normally means they will be visible), and anything not part of the named vertex group will be made non-visible.

Cube showing the masked parts of the mesh that are part of a selected vertex group. In this case highlighted in yellow.

The effect of the vertex group on the underlying Cube with a Mask Modifier active.

The 2 screenshots above show, first the underlying vertex groups assigned to the Cube (highlighted in yellow) and the second image shows the affect on the cube when it has a Mask Modifier applied to it.

Any of the methods for assigning vertex weights to a mesh work with the Mask Modifier, however the actual weight value assigned to a vertex group is ignored by the Mask Modifier. The Mask Modifier only takes into account whether a set of vertices are part of a group or not, the weight is not taken into account. So having a vertex group weight of say .5 will not make a partially masked mesh. Just being part of the vertex group is enough for the Mask Modifier even if the weight is 0.

• Selected Bones:

Selected Bones is useful in pose mode or when editing an armature. Enter the name of the armature object in the Ob: field. When working with bones in pose mode, vertex groups not associated with the active bone are masked. The Inverse button can be useful to see how a bone affects the mesh down the chain of bones.

Screenshot showing the Mask Modifier panel settings with the Selected Bones option highlighted in yellow.

• Inverse:

Normally when the Mask Modifier is applied to areas of a mesh the parts that are under the influence of the Mask Modifier are left visible while the parts that aren't are hidden. The Inverse button reverses this behavior. In that now parts of the mesh that were not originally visible now become visible and the parts that were visible become hidden.

Screenshot showing the affect on a Cube with a Mask Modifier with the Inverse button not active.

Screenshot showing the affect on a Cube with a Mask Modifier with the Inverse button active.

[edit] Examples

Example Blend file using Mask Modifier

[edit] See Also

Put related links here.

Manual