Displacement broken edges

[LudvikKoutny]

in this particular case the only thing you can do is bake the texture then fix the seams in your program of choice.
It looks like corona does some kind of blend on the seams, no idea but something like that.
In your sphere example file, which is a different case from your tree model, you could just use a triplanner which would blend the seams.

It would be nice if for examples like your tree it would not break. Best just to email vlado your tree file and ask what he can so in the future.

It's not blending, it's just displacing without breaking. I mean you can think of it in the same way as if the seam would not be on the edges of UV, but just in the texture itself. Like if you'd offset the texture in photoshop by 50%, displacement would not break, you would just see the seam in texture pattern being displaced. If you have black pixel next to a white pixel on your displacement map, and they are not on the edge of UV isle, then what you see is vertex close to the white being pushed up, and connected to the other vertex close to black pixel that's down. It just creates slope polygon. and I see no reason why that should not happen also on UV isle borders.

I just can not understand why V-Ray has to break them.

The thing is that I can not afford to fix the seams. I have numerous bought tree model, and my time budget to take them, update their materials to look better, and put them into the scene is like 3 hours. If I had to take every tree, put it inside some sculpting app, and paint over every seam, then 3 hours would turn into 3 days.

Another reason this is not an option is that to have sufficient detail, I need to take advantage of texture tiling, have texture tile numerous times over one UV grid square. If I had unique unwrapped UVs for the tree, with edges painted over, I would have to use huge maps, like 16x16k, to have similar level of detail for closeups. That is not an option either, as the scene is already complex as is, and doing such things, I would run out of memory.

My example scene was just so that someone can try if they figure something out with current mapping. I would obviously not be able to use triplanar on tree, because bark texture needs to flow with every branch.

[Companioncube]

my dirty fix. you just need to create a mask of the UV borders which i did in photoshop with an inner and outer glow. not great but at least it stops the break. the bark texture is instanced in my setup so you can scale using the tiling in the bitmap.

[Morbid Angel]

my dirty fix. you just need to create a mask of the UV borders which i did in photoshop with an inner and outer glow. not great but at least it stops the break. the bark texture is instanced in my setup so you can scale using the tiling in the bitmap.

No I get Recon's point though. You can't create masks for a hundred or a thousand of different objects. If it works in max displacement / corona, it should also be possible in vray. I guess its time for dev to chime in.

[jstrob]

Any solution to this?

What v-ray version are you usingRecon442?

i have the same problem right now with V-Ray lates stable (35003). I made several models from 3D scans cleaned in zbrush with previous vray version with a lot of uv seams and there was no problem with displacement at the uv border but now I am doing something looking like a three in zbrush (micro-anatomical structure) and I am getting bad seams all over the place and can't get rid of them...

[LudvikKoutny]

I am using 3.5 release

[jstrob]

Ok.

There seems to be something different in the way V-RayDisplacementMod handle uv border in V-Ray 3.5 versus 3.4. I just downgraded to see:

V-Ray 3.5:


V-Ray 3.4: still noticeable but a lot better and when I add bump map it's even better but in 3.5, it's still bad even with bump.

[LudvikKoutny]

Hmm, that's interesting!

[jstrob]

It was 3.40.03 (04-10-2016) and 3.50.03 (20-02-2017)

[LudvikKoutny]

Yep, so I guess some sort of regression.

[Nearl]

Turn Filter Blur to 0. Don't trust the filter texmap checkbox...unless they fixed it doesn't do anything whether it's on or off. Removing texture filtering fixed a number of my displacement seam issues. VRayHDRI has better filtering options.....but off seems best when artifacts show up.

[jstrob]

Yes Good idea. I always put it to zero normally but in this scene I just unchecked the check box.

But now it's strange cause I reinstalled 3.5 just to be sure and now I am getting this:

The uv border seems now like in 3.4 but no antialiasing...

[jstrob]

Just in case you are curious, I had to changed Vraylanczos to mitchell-n to get back my antialiasing. When reseting it back to vraylancsoz it is coming back. very strange,

[Nearl]

Hm....try cutting the blur in you bitmap loader to .01

[jstrob]

Hm....try cutting the blur in you bitmap loader to .01

in my case it was alreayd at 0.01 in te HDRI blur.

[jstrob]

I am sorry but I have to say that my previous render comparison between 3.4 and 3.5 was probably bad. I think i maybe didn't have the exact same settings in both. And finally it seems 3.5 is ok. I downgraded to 3.50.02 anyway cause I was getting many unhandled errors with 3.50.03 so I will se if I get others with .02.

Meanwhile I found a way to get slightly better results: I use 16 bit(tif) displacement instead of 32 bits (exr) from Zbrush.