Lost Newbie Needs Help With: Underwater Post Process Masking


People have probably answered this question before but I’ve had a hard time grabbing information and knowledge to understand what I even can use from the threads that I’ve read since the questions and answers hasn’t really been aimed to my project specifically.
So I want to try to create some sort of underwater city looking like this:

So for me to achieve that kind of effect I need to mask out a big sphere in the underwater post process material that I got from
A kind person helped me out with a few problems I had and then he later explained to me somewhat what I should do to achieve the effect but unfortunately with my lack of knowledge I didn’t really catch up with a lot of things he said, or I did understand the concept, but not how to achieve it, and if I am to experiment with the underwater material I would probably mess everything up and probably cause end of the world etc.
This was his comment:
(To cut a sphere shape from the post process “material” it is always possible to mask it inside that material. The best way to do it is using distance fields where you would put an invisible sphere covering what you want and get the value from distance field from it and subtract in the material from the effect, leaving a completely clean area… So far, this subtraction would need to occur only when the camera is inside the sphere, otherwise you would be seeing a hole (of half a hole when you have a dome) where the city is and this is not desirable, since what you want is to get rid of the underwater effect while inside the dome.)

So I’m asking if someone could assist me further, perhaps add me on Skype or something for chat purposes.
I don’t know how much work it is to mask out a simple sphere form out of a post process material, perhaps it’s not that much to deal with. But I feel like I still need further help with this, because once/if I get this done, then I can continue with everything else on my own. But it is just the post processing and masking that is a new area for me and I’m not exactly a person with the best learning capacity when reading various forums etc.

I just want a clean empty area shaped like a sphere :c
Unless there’s any better solutions out there to achieve this surrounding aquatic effect?

ok, iv’e modified my material to an inverted sphere mask, this should do exactly what you need it to do.
the important parts are the top scene color that goes into the lerp, the bottom sphere mask in the alpha, and with the custom fog, plug the result from the material you have now into the b of the lerp.
create an instance of that material and put it in the post process then you can adjust the scalar parameters to what you need in the instance material.

Edit: ignore the bottom screen UV’s and boxmask nodes

Thank you so much for your effort for trying to help me, however, the material that was given from the community project looks like this and I’m not 100% sure how to edit it.
Your layout seems 100 times more easier to read and understand but I assume that the community project has way more functions as well which is why it looks the way it does :stuck_out_tongue:
So I was wondering if you can see already by now if you know how to edit the material that was given by the project, because all I really wanna do is to add the mask, the other things you mentioned apart from the mask is pretty much there already… if I get everything right. But instead of simple masks they got tons of “stencils” and “custom stencils”. I tried to remove the “stencil buffer mask” area but that completely removed the underwater effect overall lol. So are you able to tell how to simply add the sphere mask part onto the blueprint that was given from the project?

I will try to make a new project and see how your blueprint works out for me… and if I/you are unable to know how to add the sphere mask onto the community project without messing the blueprint up then I guess the only way would be to create a complete new blueprint from scratch… :confused: