DocumentationSubstance 3DSubstance 3D Designer

Union smooth

Last update: May 6, 2026

Union smooth icon

In: SDF function > Operator

Description

Returns the added volumes of two SDF shapes, with adjustable smoothing of the edges of their intersection.

INFO
To learn more about concepts and workflows involving SDF functions, go to the dedicated page: Working with SDF functions

Inputs

SDF 1 Float
The first SDF shape.
SDF 2 Float
The second SDF shape.
Smoothness Float
The smoothing radius, starting from the intersection’s edges.

Default: 0

Note: hard edges may appear where the smoothing radiuses intersect.
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