Decide which measurement boundary defines the coordinates
A pallet drawing may give the full outside rectangle, while a marked working region lies inside its edges. Entering edge clearance constructs that inner region mathematically. The decision here is how to connect the tool's returned coordinates to the real measured boundary. A correct count with the wrong origin can put a proposed case into a border that the operation meant to leave empty.
The model uses one equal clearance value c on all four edges. Starting from full length L and width W, usable dimensions are L minus 2c and W minus 2c. The usable region starts at coordinate (c,c) in the original base coordinate system. Both the dimension reduction and the origin shift are necessary. Reducing dimensions while still drawing placements from (0,0) describes a different region.
Compare two insets on the same measured base
Assume a hypothetical 1200 by 1000 mm full base with identical 580 by 380 mm cases. Set case gap to zero and allow horizontal rotation. With ten-millimetre edge clearance, usable dimensions are 1180 by 980. The mixed search returns five cases, optimal by the area upper bound five. With thirty-millimetre clearance, usable dimensions are 1140 by 940; the search returns three, best found, with area bound four.
| Clearance | Usable dimensions | Allowed X interval | Allowed Y interval | Mixed count / ceiling |
|---|---|---|---|---|
| 10 mm | 1180 by 980 mm | 10 to 1190 | 10 to 990 | 5 / 5 |
| 30 mm | 1140 by 940 mm | 30 to 1170 | 30 to 970 | 3 / 4 |
| 500 mm | 200 by 0 mm | 500 to 700 | 500 to 500 | 0 / no usable rectangle |
The thirty-millimetre result is a valid three-case proposal, not proof that four is impossible. The five-hundred-millimetre example is an input diagnostic, not a recommended border. A usable width of zero leaves no two-dimensional region, so the engine reports infeasible before attempting placements. A negative usable dimension is likewise not an area that can be packed.
Verify the shifted coordinates by hand
In the ten-millimetre run, returned straight rectangles can start at (10,10) and (590,10), each 580 by 380 mm. Their far X edges are 590 and 1170, within the allowed interval ending at 1190. Three rotated rectangles start at (10,390), (390,390), and (770,390), each 380 by 580. Their far Y edges are 970, within the allowed 990. These are coordinates relative to the original full base.
The zero case gap allows those rectangles to meet at neighboring edges. Their border is still ten millimetres or more. Edge clearance has not secretly introduced spacing between every pair of cases. Review the coordinate extents individually: a start inside the usable region is insufficient if the far edge crosses the inner boundary.
Reproduce the two candidate records
Open the ten-millimetre inset and the thirty-millimetre inset. Each uses a one-layer height budget for illustration. Inspect the coordinate list and the visible border rather than checking only the count.
For a zero-width diagnostic, set clearance to 500 on the same full base. Expect an infeasible result because the cleared Y interval collapses. Do not repair that input by treating its arithmetic area as an absolute value, dropping one side's deduction, or allowing cases to cross the border. Verify whether the original measurement or clearance request was entered incorrectly.
Avoid subtracting an already measured inset twice
If a survey directly measures the usable working region as 1180 by 980 mm, there are two coherent representations. Enter the full 1200 by 1000 with ten clearance, keeping coordinates tied to the full-base origin; or enter the usable 1180 by 980 with zero clearance, keeping coordinates tied to that inner region's own origin. To map the second representation back to the full base, add ten to both coordinate components.
Entering 1180 by 980 and another ten clearance instead creates a 1160 by 960 region. That applies the border twice. It may return the same count in some examples, so equality of counts does not validate the measurement model. Compare usable dimensions and the physical origin explicitly. The coordinate record should state whether (0,0) is the full base corner or the inner marked corner.
Recognize requirements this single inset cannot represent
Unequal borders on different edges, recesses, blocked corners, and irregular exclusions are not encoded by one clearance field. A smaller conservative rectangle can model an explicit subset if its position is recorded, but it is not a proof of the best arrangement around those exclusions. Do not average unequal borders and assume every edge requirement has been satisfied.
The inset describes declared geometry only. It does not determine a hand clearance, package protection, or load rating. Obtain the boundary requirement and measurement method from the responsible operation. When the next task is completed-load floor planning, measure that object's outside footprint separately; the case-layout inset does not automatically become a wall clearance in the next equipment rectangle.
Coordinate-origin record
Full measured base: 1200 by 1000 mm. Original origin: its lower-left drawing corner. Required equal edge clearance: 10 mm. Usable rectangle: 1180 by 980, spanning X 10–1190 and Y 10–990. Case footprint: 580 by 380, horizontal rotation allowed, case gap zero. Returned count: 5 optimal, area ceiling 5. Retain placed extents and coordinate origin. If using a directly measured inner rectangle instead, document its zero-clearance representation and the translation back to the full base.
This coordinate handoff resolves where the reviewed arrangement belongs, even when two input representations produce the same count. Consult the methodology for validation rules and keep the measurement boundary with the drawing.