Hook Modifier

The Hook Modifier is used to deform a Mesh, Curve a Lattice using another object (usually an Empty or a Bone but it can be any object).

As the hook moves, it pulls vertices from the mesh with it. You can think of it as animated proportional editing.

While hooks do not give you the fine control over vertices movement that shape keys do, they have the advantage that you can grab vertices directly for manipulation.

Two spheres used as Hooks to deform a subdivided cube.

Options

Hook Modifier.

Object

The name of the object to hook vertices to.

Vertex Group

Allows you to define the influence per-vertex.

Useful when you do not something other than a spherical field of influence.

Radius

The size of the hooks influence.

Strength

Adjust this hooks influance on the vertices, were (0.0 to 1.0) (no change to fully follows the hook).

Since multiple hooks can work on the same vertices, you can weight the influence of a hook using this property.

Falloff Type

This can be used to adjust the kind of curve that the hook has on the mesh, You can also define a custom-curve to get a much higher level of control.

Uniform Falloff

This setting is useful when using hooks on scaled objects, especially in cases where non-uniform scale would stretch the result of the hook.

This is especially useful for lattices, where its common to use non-uniform scaling.

The following settings are only available in Edit Mode:

Reset

Recalculate and clear the offset transform of hook.

Recenter

Set hook center to the 3D cursor position.

Select

Select the vertices affected by this hook.

Assign

Assigns selected vertices to this hook.

Note

The Hook Modifier stores vertex indices from the original mesh to determine what to effect; this means that modifiers that generate geometry, like a Subdivision Surface Modifier, should always be applied after the Hook Modifier; otherwise the generated geometry will be left out of the hook’s influence.