Editing Linked portal (section)

===Polyobject portals===
You can even place portals on polyobjects now. Connecting the edges of a polyobject with a sector matching its "interior", you can now have moving platforms. Unlike conventional wall portals, the ones on the polyobject's exterior must be one-sided. Upper and lower textures will still work, despite this. The wall portals from the inside area to the outside will have to be conventional though (2-sided with a buffer sector behind).
====Caveats====
Though this may get fixed in future versions, make sure to connect the polyobject control sector (the one holding all prototype polyobjects) to the main area it will appear in. You can use tunnel sectors or joined sectors. To avoid glitches, the sector containing the prototypes must not be the same sector as the one where polyobjects will be spawned.
====Simple moving platform illusion====
You can put a linked portal in the ceiling of the inner sector to give the illusion that a simple platform is moving on the floor. It works if you used the [[Portal_Define]] special for the line portals and if the background room has the same ceiling height, or in very small variation, in the area where the polyobject moves. Acceptable variations are at most 8 map units. Otherwise, you get bleeding effects.

The platform sector must have the ceiling height set to the maximum ceiling of the outside area. Set the '''portalceiling''' field of the sector to the same ID you used for the walls. Make sure the z offset of [[Portal_Define]] is set correctly: if the inner sector is a raised platform compared to the outside sector, the z offset should be the ''minimum'' ceiling height from the outside area, minus the elevation of the platform against the background. If it's a "moving pit", the z offset should be the negative of the height of the lowest ceiling detail from the outside area.

It is recommended to set '''portal_ceil_nopass''' on the sector, especially if there is no height variation. This prevents unnecessary side effects.

An example is available for download: [https://www.dropbox.com/s/xi1xhv92h27ptep/polyceilport.wad?dl=0 PolyCeilPort.wad].