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Specifies the method used to apply Input Mesh Attract to nCloth mesh vertices.
Non Locking

For this method, all vertices participate in the simulation. For example, Nucleus forces, Collide and Self Collide on all mesh vertices is calculated. The Non-Locking method is the default behavior of Input Mesh Attract.
Lock values of 1.0 or greater

For this method, vertices with painted Input Mesh Attract (using Paint Vertex Properties or Paint Texture Properties) values of 1 or greater use the vertex position of the input mesh. Nucleus forces and Self Collide are not calculated on these vertices during simulation. Essentially, these areas of the nCloth behave like passive collision objects.

Using Lock values of 1.0 or greater decreases simulation time and memory use particularly for dense meshes.