Right now, portal floors with overlays for things like liquids will not do terrain hits. This leads to modders having to do some messed up hack involving boom deep water in order to use a portal for deep water but also get the terrain hits. This solution, letting users of ExtraData or UDMF set a flag that will make the portal use the floor's terrain hit, is backwards-compatible and simple.
Right now, portal floors with overlays for things like liquids will not do terrain hits. This leads to modders having to do some messed up hack involving boom deep water in order to use a portal for deep water but also get the terrain hits. This solution, letting users of ExtraData or UDMF set a flag that will make the portal use the floor's terrain hit, is backwards-compatible and simple.