I cant figure out how to extend the post process, its not working as unbound for underwater, and I cant find access to it. The underwater section of my map ends at the end point of what looks like the post process box attaches to the spline.
Hello! I just had this question myself and went through a lot of experimention to figure it out⌠you need to adjust the âCollision Extentsâ for the WaterBodyOcean actor. From what I understand, the post processing only works within the collision bounds, so if you change one, the other will be affected.
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Awesome thanks for the info!
Do you know if there is a similar tweak for the WaterBodyLake/WaterMeshActor?
If I increase the Channel_Depth to 2000 (in the default 4.26 WaterTestMap â WaterBodyLake example) then it causes a similar offset issue where the underwater post process doesnât engage until you are near the centre of the lake. Unfortunately, there is no âCollision Extentsâ equivalent to tweak.
Thereâs presumably an âextent/boundsâ setting somewhere, but I canât find it.
I was able to replicate your bug by creating a new landscape and just adding a lake: when I move the camera to the lake floor or just under the waves, I didnât see any underwater post processing effects in those areas. There is a âEnabledâ checkbox for the lakeâs âUnderwater Post Process Settingsâ , but itâs already checked⌠and unchecking it just removed the effect entirely. The only fix I found was adding an ocean to the landscape and set the splines so that itâs outside the landscape (so it doesnât deform any part of the terrain) - this automatically fixed the bug without having to change any collision extents.
However, this fix is limited to lake depths above [about] 30,000 (should be fine for most lakes!), as it doesnât seem to render the underwater effect below that. Even if I changed the Z Collision Extent for the ocean to 100,000, nothing changed⌠in fact, no matter what I changed the Z Collision Extent to, it didnât seem to make any difference. Only changing the X and Y made a difference (or at least a difference I could see, as the post processing box for the ocean changed when I changed the X and Y, but not when I changed Z). From what I see, changing the Z collision extents is probably a bug in the plugin itself.
Tl;dr: add an ocean around your entire landscape (unless you already have one), and that should fix the error as long as your lake isnât just a really thin, deep ocean.
Thanks for the tip ixm.ibrahim (and the mini investigation), it works.
I didnât really want to add a whole body of (hidden) ocean in my scene just to make the lake underwater transition work, but Iâll happily use this trick for now, until there is a more permanent fix.
Well done for finding the hack.
Having the depth issue with the ocean body, the terrain max depth from 0 is about z: -25500 but the ocean post process effect (lower bounds) stops at z: -20000 leaving a gap. I cant figure out anyway to extend it in negative z aside from creating additional post process volumes.
I had this same issue with the lake and I found that adding more spline points fixed things.
Old post, but I followed this video and was successfully able to fix the post process depth issue without adding an ocean body to the scene. Specifically around the 5:30 mark. Let's Build the RPG! - 16 - Unreal Engine 5 Water System Beginner Tutorial - Lakes and Rivers - YouTube
Changing the Channel Depth seems to increase the post process depth.
Side note: Your landscape seems to need âEnable Edit Layersâ checked for this value to dynamically edit the landscape geometry.
Same issue with River body. Trying lake first then River worked too.
Thank you for your post it solved my problem. Using UE 5.3.2
One thing to note for others that may find their way here: I did not have âAffects Landscapeâ enabled and as such was unable to change the Channel Depth. So need to enable âAffect Landscapeâ first, then change the Channel Depth and then disable Affect Landscape. All good.
Cheers
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As unintuitive as that was, it worked. It does make sense to some degree as the âAffects landscapeâ option makes the value of Channel depth go deeper while also extending the post process volume. Thanks, this should be marked as the solution!