LOS check fails when above swimmable 3D floor water

Post by **Player701** » Tue Nov 06, 2018 2:45 pm

There seems to be a problem with line of sight checking if the enemy is underwater and the player is above the surface. It appears that LOS checks will fail as long as the player is in the same sector that has the swimmable 3D floor applied to it.

Attached to this post is a test map to demonstrate the bug. The testing procedure is as follows:

Go to MAP01 and immediately enable god or noclip so that you won't be kicked back by enemy attacks.
Notice that the Chaingun Guy sees you. Type "warp -440 -75 0" in the console to trigger the buggy behavior.
At this point, the Chaingun Guy doesn't seem to have a clue where you are, despite there being a direct line of sight between you and the enemy. As long as you stay close enough to the water but don't go into it, you will not be seen. This is also evident if you enable the fly cheat and float above the surface. You can only make the enemy see you by either submerging yourself into the water, or by going back to the starting point and hoping the enemy gets a clear line of sight.

Interestingly enough, this doesn't seem to happen with non-solid 3D floors, only swimmable 3D floors are affected. Haven't tested Transfer_Heights water yet.

Tested in GZDoom 3.6.0, g3.7pre-187-g705c87c6c

Post by **Graf Zahl** » Tue Nov 06, 2018 5:14 pm

Just a stupid typo caused by autocompletion...

Fixed.

Post by **Player701** » Wed Nov 07, 2018 4:40 am

Confirmed: LOS checks work fine with 3D floor water as of g3.7pre-210-g9661c3b53. However, Transfer_Heights-based water seems to block all LOS checks regardless of the sector the player is in. Is it supposed to be like that?

New test map attached.

Post by **Graf Zahl** » Wed Nov 07, 2018 4:52 am

Yes, that is intentional.

Post by **Player701** » Wed Nov 07, 2018 4:53 am

All right then. Thank you for fixing this.

ZDoom