In the case of rectangular (2D) optimization all pieces must be rectangular.
The pieces from Parts (also called DEMAND in previous versions) can be rotated with 90 degrees if necessarily or in the case that this decision improves the cutting performance. Rotation has no effect in the case of 1D optimization. Take care to the grain direction if you work with wood.
There are 3 types of cuttings that this program can do: guillotine (which is either free or multi-stage) and non guillotine (also called nested).
Guillotine (From edge to edge). The cuts are performed from one side to the other side.
Non-guillotine (follow the contour of pieces; nested). The cuts striclty follow the contour of the material. Cutting machines with laser, flames, water jets can perform non-guillotine cuttings as can be seen below:
Multi-stages guillotine. Cuts from one stage are perpendicular on the cuts of the next stage.
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