Part Modeling > Edit Features > Pattern > About the Pattern Feature > About Projecting Pattern Members onto a Surface
  
About Projecting Pattern Members onto a Surface
In fill, curve, and point patterns, the sketch that defines the pattern lies on a flat plane, while the surface on which the pattern members lie may not be flat. To accurately align the pattern members when they are projected onto the selected surface, the pattern leader and the sketch plane should be tangent to the projection surface. If the sketch plane and pattern leader are not tangent to the selected surface, then pattern members will follow the selected surface and curve according to the selected orientation type. Pattern members that cannot be projected onto the selected surface are removed from the pattern.
To space pattern members correctly on the surface, the following mapping options are available:
As projected—Projects the pattern leader and pattern members straight onto the surface. No adjustments are made in the spacing.
Map to Surface Space—Projects the pattern leader straight onto the surface. The remaining pattern members are placed according to the uv-lines that pass through the pattern leader. This spacing option is only available for solid surfaces. You can select this option to produce more even member spacing when the sketch or template uses equal spacing.
 
* The uv-lines do not extend past the surface boundaries. Therefore, a region of the surface that is separated from the pattern leader by a boundary is not populated by pattern members.
When you map members to a spherical surface in a Fill pattern with a Circle or Spiral template, the pattern leader becomes the pole location of the sphere. The number of pattern members is reduced automatically in the region beyond the equator to maintain the surface spacing.
Map to Surface UV Space—Projects the pattern leader straight onto the surface. Maps the remaining pattern members from the sketch to the uv-space of the surface based on their xy-coordinates relative to the first member in the sketching plane.
 
To create an evenly-spaced pattern, surface uv-lines must be evenly spaced.
At the pole of a sphere, uv-line densities are infinite and you cannot map to them.