Pattern Design for the Rest of Us
 

Creating Repeat Patterns: Blending Units of Repetition

Mirror symmetries naturally produce patterns without visible divisions between repeated units. For other symmetries, you can create seamless patterns by blending (melding together) neighboring units horizontally and vertically using the Blend H and Blend V sliders in the Parameters panel.
Blend sliders
For symmetries that allow different amounts of blending in the horizontal and vertical directions, you can change the horizontal and vertical blending independently. Otherwise, you can change only the horizontal blending and SymmetryMill either adjusts the vertical blending accordingly, as dictated by symmetry laws, or turns the vertical blending off when it is not necessary because the pattern is already seamless in the second direction.
Note: Both horizontal and vertical blending are disabled for symmetries that involve two mirrors and therefore achieve seamless patterns without blending.
Blending is useful for creating conversational, naturalistic, figurative, floral, geometric, and many other types of designs.