Boundary
Reference
Mode
Sculpt Mode
Tool
Toolbar ‣ Boundary
This tool is used to transform and deform the boundaries i.e. the unconnected edges of a mesh. The tool detects the mesh boundary closest to the active vertex and propagates the deformation using the brush Falloff into the mesh.
Note
Even if this brush can produce deformations in triangle meshes and meshes with a non-regular quad grid, the more regular and clean the topology is, the better the result.
Brush Settings
Deformation Target
How the deformation of the brush will affect the object.
Geometry
Brush deformation displaces the vertices of the mesh.
Cloth Simulation
Brush deforms the mesh by deforming the constraints of a cloth simulation.
Deformation
Deformation type that is used by the brush.
Bend
Rotates the active boundary around the local Y axis.
Expand
Moves/extends the mesh boundary in the local X direction.
Inflate
Works similar to the Inflate tool but, the vertices that are inflated are constrained to the mesh boundary.
Grab
Works similar to the Grab tool but, the vertices that are grabbed are constrained to the mesh boundary.
Twist
Rotates the active boundary around the local Z axis.
Smooth
Works similar to the Grab tool but, the vertices that are smoothed are constrained to the the mesh boundary.
Boundary Falloff
How the brush Falloff is applied across the boundary.
Boundary Origin Offset
Offset of the boundary origin in relation to the brush radius.
Constant
Applies the same deformation in the entire boundary.
Brush Radius
Applies the deformation in a localized area limited by the brush radius.
Loop
Applies the brush falloff in a loop pattern.
Loop and Invert
Applies the falloff radius in a loop pattern, inverting the displacement direction in each pattern repetition.
Usage
The main use cases of this brush are the Bend and Expand deformation modes, which depend on a grid topology to create the best results. In order to do further adjustments and tweaks to the result of these deformations, use the Inflate, Grab, Twist, and Smooth deformation modes, which do not depend that much on the topology.