Combining more than two Normal Maps in UE4

Pope Adam

Hey folks,

It's been AGES since I logged in to polycount - after getting into the industry my posting really dropped off, as I had access to so many professionals in the studio to help sort through all of my development woes.

Alas, I've now gone indie and my pool of resources shriveled - and I humbly come to my roots for support once again!


In Unreal, I'm making a palette of cliff rocks of different shapes, sizes, scales etc.  For this task I am creating a master material and instances of it for use across a multitude of different destinations types (desert, mountain, arctic etc.)

The process I'm attempting to use is failing me.  Particularly in regards to normal maps, and combining them.  Here is the workflow I'm attempting to use:

1x Tiling Normal map - finer detail normals, noise, cracks, chips etc.
1x Tiling Normal Map - larger scale tiling forms, like a Macro breakup
1x 1to1 Normal Map Bake - bakes from a high poly sculpt to low poly mesh

This is the template I'd like to follow and workflow I'd like to use if possible, but I'm running into some pretty nasty visual results when combining more than two normal maps - particularly when I use a WorldAlignedNormal (for my first two maps) and blend them with BlendAngleCorrectedNormals nodes in UE4.

The result is absolutely overblown values.  No amount of clamping, normalizing, or even adjusting the intensity of the base maps seems to create a pleasing result.


So I reach out to you, Dear Polycounters.  Is this simply inadvisable?  Is there any manual math-node setup I could use to successfully blend these three maps together for a decent output?

https://i.imgur.com/GHEGUJM.png

[img]https://i.imgur.com/GHEGUJM.png[/img]

as you can see, i'm struggling to get my image to post directly...

RyanKnudsen

I'd say you're on the right track. I recently went through Anthony Vacarro's World Building CGMA course and we went through adding detail normal maps etc. What nodes are you using to combine the Normal maps? Are you using a Lerp node? posting a good shot of your node graph would help in giving suggestions too.
Scratch that just took another look at your images!
I dont see anything that immediately jumps out at me, but this may help if you havent seen this post: http://www.jackcaron.com/techart/2014/11/14/ue4-normal-blending

edit: Only thing I can suggest right now is perhaps making a simpler material to test blending your normals without all the world aligned texture nodes and just try getting the normals where you'd like them. Eliminate as many other features as you can to narrow down/ find the problem/fix.

hazeh

Hey so I might be mistaken as I'm just an amateur with no industry experience, but from what I've gathered the manual way of adding red to red, green to green and multiplying blue on blue works best when blending triplanar maps with baked and detail normal maps. Not sure if the results are exactly correct, but they don't blow up as much.

Obscura

Have you tried disabling the " high quality normals" boolean on the world aligned normal material function?  It makes minimal to no visual difference for the cost of a lot of instructions anyways.