Refer to the exhibit.

A view filter can be configured to act only on ceilings meeting specific criteria, such as family name, type name, material, height, or another parameter. Because the missing ceiling is a 2x4 type while the visible ceilings are 2x2 types, a filter targeting the 2x4 ceiling could hide it or override its graphics without affecting the other ceilings.

A Plan Region can also impose a localized View Range that differs from the parent Reflected Ceiling Plan. If the hallway contains a Plan Region with a higher cut plane or an otherwise incompatible view range, the ceiling can fall outside the region’s visible range even though it remains present and visible in a 3D view.

The ceiling was not deleted because it is still visible in 3D. Turning off the Ceilings category through a View Template would ordinarily hide all ceilings governed by that category in the view, contradicting the fact that the 2x2 ceilings remain visible. Similarly, Hide in View by Category affects the entire Ceilings category within that view rather than one ceiling type or a single hallway element.

Reference topics: Reflected Ceiling Plans; View Range; Plan Regions; view filters; category visibility; view-template troubleshooting.

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