Contour Stretch Mapping options

Project a texture image onto a selection of an object's polygons. Rather than projecting according to a specific form, a contour stretch mapping analyzes a four-cornered selection to determine how best to stretch the polygons' UV coordinates over the image.

The following options control how a contour stretch UV mapping (UV > Contour Stretch) is calculated for a selection of polygons, and how the resulting UV coordinates correspond to the texture image.

Projection Manipulator

Method
Walk Contours
Calculates the UV coordinates by following the mesh as closely as possible from contour to contour, in both the U and V directions, and accumulating edge distances from the selection's borders. This option will usually give the best results, particularly on complex meshes.
NURBS Projection
Creates a NURBS surface using the contours and borders of the polygon selection and then projects the polygon selection onto that surface to calculate its texture coordinates. This method is especially useful for bumpy, terrain-like surfaces.
Smoothness 0, 1, 2, 3
Sets the smoothness of each edge of the NURBS surface.
Offset 0, 1, 2, 3
Sets the offset of each edge of the NURBS surface.
User defined corner vertices
Turn on this option to pick four corner vertices one-by-one, and then press Enter to finish. By defining four corner vertices and performing a projection, you can get more accurate result. The vertices must lie on the boundary of the initial selection.
Insert projection before deformers
When on (default), inserts projection before all deformers that are associated with the mesh. This helps to keep the UVs intact when you modify the deformer. Otherwise, the UV changes while you modify the deformers.