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Surface Deform Modifier
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The Surface Deform Modifier allows an arbitrary mesh surface to
control the deformation of another, essentially transferring its motion/deformation.
One great use for this is to have a proxy mesh for cloth simulation,
which will in turn drive the motion of your final and more detailed mesh,
which would otherwise not be suitable for simulation.


Options
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.. figure:: /images/modeling_modifiers_deform_surface-deform_panel.png

   Surface Deform Modifier.

Target
   The object to which to bind. (This setting is unavailable after binding).
Interpolation falloff
   How much a vertex bound to one face of the target will be affected by the surrounding faces.
   This essentially controls how smooth the deformations are.
   Note that while lower values result in smoother deformations,
   they may also introduce slight artifacts.
   (This setting is unavailable after binding).
Bind
   Bind the current state of the modified mesh to the current state of
   the target mesh, such that any later change in the target mesh will
   deform the modified mesh as well. Note that until the bind has been
   executed, this modifier will have no effect whatsoever.
   (This does not affect the target object).
Unbind
   Once the mesh is bound, the *Bind* button changes to *Unbind*.
   Executing this frees the modified mesh from the target, and resets it to its original shape.
   (This does not affect the target object).

.. note::

   The meshes are bound with regard to global coordinates,
   but later transformations on the objects are ignored.
   This means that one can freely transform the target or modified object after binding,
   without affecting the modified object.
   The modified mesh will only pick up changes to the target object's mesh itself.

.. note::

   The further a mesh deviates from the target mesh surface, the more
   likely it is to get undesirable artifacts. This is an inherent
   characteristic of surface binding in general, so it is recommended
   to have reasonably well matching meshes, in order to get a good bind.

.. warning:: Target Mesh Validity

   While there are no restrictions with regard to the modified mesh,
   the target object's mesh has a few constraints, which if not followed, will prevent a successful bind.
   The target mesh has to follow these conditions:

   - Must **not** contain edges with more than two faces.
   - Must **not** contain concave faces.
   - Must **not** contain overlapping vertices (doubles).
   - Must **not** contain faces with collinear edges.

Example
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.. figure:: /images/modelling_modifiers_deform_surface_deform_example.png

   Cloth simulation copied to an arbitrary mesh with rings as duplifaces.