openscad triangle generator 3D-model almost 2 years 18 triangle pen 3D-model almost 2 years 1 PolygonTtakji6Set 3D-model almost 2 years 1 Penrose Triangle Illusion 3D-model almost 2 years 8 Throw Pillows 3D-model almost 2 years 88 Set of Abstracts 3D-model about 4 years 185