S = solid.loft (REGIONS) returns a solid.Shape that passes through every geom.Region in the cell array REGIONS, in order, with a smooth surface between them. This is how a transition is modelled: a duct from a rectangle to a circle, a tapering arm, a handle that swells in the middle.

Each region is a section and lies where its plane puts it, so the sections are placed by giving the regions’ planes their origins and normals. They need not be parallel: a duct can turn a corner as it changes shape. The outlines need not have the same number of vertices. Their first vertices are joined to one another, and so are the vertices that follow, so a loft twists when its sections do not start at corresponding points.

Every region must have the same number of holes, and hole k of one section flows into hole k of the next, so a duct of uniform wall is a loft of regions with one hole each.

S = solid.loft (…, 'Ruled', TF) joins consecutive sections by straight lines when TF is true, so a loft between polygons has flat faces and a crease at every intermediate section. It is false by default, which passes one smooth surface through every section. With two sections both give the same solid.

 ## A square of 20 at the base becoming a circle of diameter 12 at 30
 base = geom.Region ([-10, -10; 10, -10; 10, 10; -10, 10]);
 top = geom.Region ([6, 0, 1; -6, 0, 1]);
 top.UCS = geom.UCS ([0, 0, 1], [0, 0, 30]);
 S = solid.loft ({base, top});

See also: geom.Region, solid.extrude, solid.sweep

Source Code: solid.loft