Normal Map Blending

[Hitpawz]

http://imgur.com/a/lktcn

How do I stop this from blending the way that it does? I have alpha cropped normal map textures added, but they are overlaying or doing a soft light when I paint them down on a paint layer.

When I hold the brush over the surface, it's overwriting as if it's normal and this is the effect I want. I don't want a bunch of skulls all blending into each other, I want to layer them down so that each new skull completely covers the one behind it. That way I can completely fill the surface with a collage of them. As it stands, if I do this, I just get a big blended mess that you can't distinguish at all.

I don't want to have to create a black/white alpha mask for something that has an alpha channel as it would add more images to my shelf that I don't need if this worked. Besides that, I would need a new layer for every skull I painted and we're talking about 1000.

Any advice or help?

[僕の名前 (仮)]

I'd recommend use heightmaps instead of normal maps for that kind of stuff. They are blending better and you also can't rotate normal brushes, otherwise they will look incorrectly.

(dont forget to use 16 or 32 bit, not 8 bit heightmaps)

[僕の名前 (仮)]

Or better yet, use sculpting software, it will have more smooth normal map than converting heightmap texture nto normal (converting heightmap into normal sometimes result in aliasing)

[Hitpawz]

I would sculpt it but I don't really want to have to slam my system as hard as it would require to subdivide it to a bunch of millions of polygons. I'd much rather be able to paint this out with a scatter brush so I can add this effect quickly to any kind of object. This is especially true for objects that don't subdivide well.

Baking out heightmaps is ok but I keep having to manually adjust the range and it's a bit of a pain in the long run.

The only solution I've found that's viable at this point is to paint my normals onto the base color channel and then export that out and bring it back in as a normal map. This is "OK" but it's not as intuitive and edits to the collage later require those same production steps.

I think the brush tool also needs a blending mode option like in Photoshop, not just for layers.

[Mr Chappy]

Do you have the skull model?

[Hitpawz]

Yea, I went with your suggestion and just spent the time rerendering the height maps and typing in the values.

[Hitpawz]

I still don't think that when painting normalmaps onto the same layer that the brush's blending mode should be overwritten against standard painting methods just because it's the normalmap channel you're painting. It makes creating a complex normal map from various textures very difficult. It really should be an option for the paint brush to choose the blending mode on application. Just my 2 cents on it.

[Mr Chappy]

Another option would have been to assemble multiple copies of the skull mesh on the hammer(?) object in your 3D package.
You could use decimate to reduce the tri count on the smaller ones that need less detail.

Once assembled you could join them all together as one object, re-top this, then bake in SP.

It would be more work but the end result would also be far better...
Much easier to adjust the layout of the skulls this way too :)

[123]

Paint each skull on a new layer, and switch each layers normal channel blending to "Normal"(normal like the one you have on base color channel).

[僕の名前 (仮)]

Gene Siwako, it will still have incorrect tangents from rotated brushes.

[Hitpawz]

The rotated tangents, in MY case, isn't an issue since I didn't need to rotate the brush too much for the effect to work. The big problem is that even though I'm painting an alpha cropped skull, it actually lays down a complete square the size of the brush. So I get the normal details of the skull, but then the 1,1,.5 flat normal color all around it. This makes setting the channel to normal blending is an issue. Also, 1000 layers is a problem.

Going with a height map was a good option, but there is another solution that was provided by Allegorithmic on their forums.

"Hey, here is a 2017.2 hack (maybe someone will come with a cleaner solution :) )

In the textureSet settings, create a user0 channel and set it to RGB16F.
create a new layers and paint your normal map info on the user 0 channel (deactivate the other ones).
create an anchor point from this layer.
Create a fill layer, and leave only the normal channel activated.
for the normal channel choose the anchor point you have created and set it to user0

it worked for me ;)"

- Vincent Gault

[僕の名前 (仮)]

That makes sense then, it was an interpolation error of blending 8-bit colors.