A glass cutting program is usually judged by its screen: coloured rectangles, a utilisation figure, a pleasing picture. The real output, though, is the sheet of paper standing at the bench. If that paper is wrong it does not matter how good the screen looks, because the glass is cut from the paper and cut glass does not come back.
The first thing the paper has to get right is the order of cuts. Glass cutting is guillotine: every cut crosses the sheet from edge to edge and there is no partial cut. So a plan is not only about fitting parts in, it has to establish the sequence in which the cuts will be made. A layout that fits but cannot be cut is of no use in a workshop. The engine produces layouts that respect that constraint, and the cut lines are drawn onto the plan.
The second is readable measurements. Each part carries its width and height and shows which order it belongs to. In the glass trade, sizes close to each other are common; 490x251 and 491x286 cannot be told apart by eye. If the paper does not make that distinction the person at the bench cannot either, and two pieces get mixed up.
The third is blade allowance and edge trim. When neither enters the plan, a layout that fits on screen does not fit on the bench. The blade allowance is the millimetres lost at every cut; the edge trim is the unusable border of the sheet. Both sit under your hand as parameters and arrive with defaults ready, but they have to be part of the arithmetic.
The same engine works the same way on different jobs. The difference between cutting mirror and cutting float is not in the software but in the glass type on the record. The bead cutting list comes out of the same order and prints in its own layout, because the person cutting bead is not the person cutting glass and both lists on one page make both hard to read.
For the plan to be applied at the bench the cut sequence has to be readable too. When the plan says which cut comes first the operator does not have to decide; the decision has already been made. Without a sequence every operator cuts by habit and the same plan gives two different results on two benches. That difference shows up not in the utilisation figure but in the pile of waste.
That is why seeing the plan on screen and exporting it as a PDF is not decoration. The job of a cutting plan is to make sure the plan built in the office can be applied exactly as it is in the workshop. Every difference in interpretation shows up in a piece of glass that has already been cut, and there it cannot be fixed.