multiple UVs problem (again)

[portnicki]

Hi (Paul),

I just can't get this to work.
So I have a mesh, with 3 different UVs. The material on that mesh has bump, diffuse and displacement.

Both the Diffuse and Bump maps react correctly when I toggle between the different UVs in the "Octane Mesh UV Projection".
But displacement just doesn't do anything. It's stuck with first UV in the list. No matter what I do.
I tried renaming the UV's, reloading the scene, restarting modo. I've even updated from Octane 2.x to 3.x now, just to make sure it's not that.

help

scene in the attachment.

[face_off]

Both the Diffuse and Bump maps react correctly when I toggle between the different UVs in the "Octane Mesh UV Projection".
But displacement just doesn't do anything. It's stuck with first UV in the list. No matter what I do.
I tried renaming the UV's, reloading the scene, restarting modo. I've even updated from Octane 2.x to 3.x now, just to make sure it's not that.

I suspect that displacement mapping only works on the first UV map. That's a limitation with the current displacement implementation in Octane.

Paul

[portnicki]

ok .. that's a little odd.
So the workaround would be to make sure the UV map I want for the displacement is the first one on the UV's list, and the UVs for bump/diffuse should be switched to the 2nd/3rd, right?
I'll try it out tommorow then and report back.

[face_off]

Yes, UV Set 1 will always for used for Dsiplacement -> http://poserphysics.blogspot.com.au/201 ... pport.html

Paul

[portnicki]

ok Paul, one more thing though.

What I need is to have both the displacement nad bump on top of that. I remember that at one point of Octane/plug-in that did work. It required the trick of using a mix material node and hooking up the displacement to that mix material, instead of the material itself.
It does not work right now for me. Has anything changed in that regard?

[smicha]

Hi portnicki,

Bump is working on displacements but unfortunately normal maps don't combine neither with bumps nor displacements - this is what I've been asking for long time (not Paul, but rather Marcus for the standalone).

Attached it the simple scene with closeup on a sculpted acanthus leaf where I used displacement and bump at once - clearly it works. Make sure you have properly set scaling and projection settings for bump. Also my trick is to use 180deg. smoothing angle for surface normals (shader tree, material) for better displacement map performance. I also load cage for octane geometry to speed up modo viewport and use 1-2 sub. div. Catmull-Clark for octane. I am not sure if there is any way to get consistent (without cracks in geometry) displacements without further usage of subdivision level. Could you please post a screenshot of your geometry with displacement map without turning on sub.div. ?

[portnicki]

@smicha

thanks for the tips, but unfortunatelly nothing works.

I mean sometimes it works when BOTH the bump map and displacement map share the same UV. The moment I switch the bump map to use the UVset #2, there is no more bump at all.
Even when I switch back to UV map #1 ... it doesnt work again magic I think this is a bug of some kind. It's driving me mad...

I tried switching the Live Geometry update and Load Cage on and off. Doesn't change anything. I tried switching the mesh to regular polys, insted of sub-D's. Also nothing.
I even thought that rotating the texture might do the trick. But no luck there either.

here's the screenshot you requested (the bump is nowhere to be seen, just displacement):

[portnicki]

ok, since we're talking about this, here's another issue I stumbled upon with the same mesh and same material.

So actually both the bump and displacement work now.... only if the bump is set to UV set #1 (I did it your way smicha, just connecting both bump and displacement to the same material - not using this trick with mix material displacement).
Number 2 and 3 UV sets result in just displacement overriding the bump.

But here's another problem. I get this "checker" effect on my material when mixing bump and displacement maps (note that these maps are two, totally different images).

Any ideas?

I thought it might be a scale problem (the meshem I import from Rhino are usyally very, very big in modo), but after scaling down to 1% of the original geometry, it's exactly the same.

[face_off]

Whilst using bump and displacement maps together is possible - I think in some situations it will not render well - as you have found. Otoy recommend not mixing the two.

Paul

[portnicki]

ok, just for anyone interested. The checker artifact problem was resolved by subdividing the mesh one more time.
But I still can not choose different UV sets for displacement and bump. When I do, the bump disappears.

Hope otoy will fix this in the future releases. Displacement + bump comes in handy very often imo.

thanks for your help guys.