Planar Pleat takes a flat geometry and applies a deformation to add a pleat. It preserves distance along the original plane, so avoids stretching or distorting the geometry.
Additional seams are not generated, so the geometry should already have edges along the fold lines to avoid rumpling the boundary of the pleat.
Points to deform with the pleating operation.
The plane used for deformation. The pleating will be done in the direction orthogonal to this plane.
The center of the first pleat fold.
The direction of the pleat’s fold line. Measured in degrees off the principle axis of the build plane.
What style of pleat to create.
An accordion pleat is V shaped ridge.
A knife pleat is an accordion pleat, but is folded asymmetrically so the top can fold back along the plane.
A box pleat is a pair of opposite facing knife pleats that cancel each other out.
The angle of the first fold. 180 will fold fully back on the original plane.
The combination of inside fold, outside fold, and spacing often are specific to the designed pleat. This provides a universal scale to apply on top of that to generate the same shaped pleat but at larger or smaller sizes.
The distance from the first fold to the second. For accordion pleats, symmetry is enforced so this also controls the second distance. Note this is distance along the original plane, the resulting geometry will be shifted as the inside fold is raised above the plane by the fold angle.
Distance from the second fold the the third fold. The third fold undoes whatever lift was induced by the fold angle, returning the geometry back to the plane and a flat direction.
Distance between successive pleats. For box pleats, this must be large enough for the top of the box pleat to have sufficient space to avoid self-intersection.
Number of times to repeat the pleating operation after the center location.
Number of times to repeat the pleating operation before the center location.
Using before, as opposed to after, can be helpful depending on which direction you want the unpleated geometry to be dragged to make room for the pleat.