Vray Displacement Mod + Distance Tex smoothing uv issue

[piotrus3333]

ok, since I find this quite interesting but away from pc today - an idea:
I think I heard long time ago that VRayDisplacementMod would work on top of 3dsmax displacement and VRay’s subdivision type displacement could be used to smooth geometry. is it possible?

less crazy idea - using VRayDirt instead of VRayDistanceTex?

[Kevinb]

I can try the double displacement option to test it.

I can also try the Vray Dirt to test it out.

The main thing im struggling to get my head round is even if i use VrayDirt or DistanceTex and then bake it, surely its read as just a map then and blurring it should help in some way?

My brain hurts here lol. I have noticed this problem before in projects but only now will it effect the quality.

This thread has the same issue, so im going to try photoshop blurring the map.
https://forums.chaosgroup.com/forum/...-surface/page2

[Kevinb]

Ok tested double displace, (3ds and vray versions stacked) and this didn't do anything unfortunatly.

But subdiv mode cleaned things up nicely BUT with the seams splitting even with "keep continuity" on. 3D mapping cleans that up nicely if used BUT causes the above issues.



If i toggle off 3dsMax Displace in the stack, nothing changes.

Am i missing something?

[fixeighted]

There's nothing wrong with anything apart from the jpeg you use for displacement. Make a better one - 32bit and the problem will go away
You easily test it by sticking any procedural in the slot instead.

[piotrus3333]

VRayDisplacementMod >> type subdivision, amount = zero to do just the smoothing.

[Kevinb]

Hi Fixeighted, I did bake a 32bit tga also and placed it in the displace with no effect there.

I will test it out again though just to be sure.

Piotrus3333 i will do that also.

Thanks for all the comments by the way its good to have many minds on it.

Will post up results this afternoon.

[Kevinb]

VRayDisplacementMod >> type subdivision, amount = zero to do just the smoothing.

piotrus3333

VrayDisplaceMod on its own in the stack, set to dubdiv get 0 displacement get to "amount 0". Maybe im not following your there but...

With
-Vraydisplace
-Displace

This doesnt work well.

This method with just 3Ds Displace mod and VrayDisplace to smooth, I could do with 3Dsdisplace, snapshot, then smooth the non shaped mesh. I think that's where that route ends.

[Kevinb]

Side note here. The bumpy feel is ok as i know that can be from colour noise in the map. Its the squares in the shading we are trying to fix here. Just to remind where we are at.

[fixeighted]

I did a very quick/dirty copy of your map in PS to show the difference it makes.
Naturally you should adjust your edge length to suit...I put it at 0.5. I also made sure the displacement map was unfiltered, so 0.01.
If you had a larger map then of course you could likely get away with a higher edge length, if it gives any speed difference for you.

[Kevinb]

Brilliant stuff fixeighted. Im about to try this method. 32bit image, any file type for this preferred?

[fixeighted]

Draw it out in a 32 bit Photoshop doc...I just traced over yours a bit
Saved as exr. Glad it's of use

I remember this displacement stuff messed with my head years ago, until I finally figured out that it's all down to it needing to be 32bit, therefore having sufficient greyscale values to describe the surface.
I remember making bigger and bigger...aaand bigger pngs, all to no effect, on a deadline LOL
We get there eventually

[Kevinb]

Awesome. Sure, im going to bake out a 32 bit exr from the DistanceText now. Then pop that in the VrayDisplacement. Will post the results

[fixeighted]

Hmm, I haven't actually tried to bake one out in this way. Should work fine though, according to this post https://forums.chaosgroup.com/forum/...ment-with-vray

[Kevinb]

Hi

Right interestingly both EXR and JPEG are now smooth...
So maybe it was removing the filtering on the image (0.01) and the edge length but somewhere along the line of the last amends, it made both maps work ok. (jpg and exr)


1st EXT
2nd JPG

[fixeighted]

In both of these I am still seeing a 'dimpling' which is effectively still the pixellation but much finer, so maybe the bake didn't work as expected.
Here is the map that I made for comparison of the pixel values. https://www.dropbox.com/s/bqjy92q4fnhxzcx/A.exr?dl=0
In that post I linked I noticed that in a dialogue you need to input the output values within a range for it to export
the right values.
Were you not needing a smooth surface overall? Then you can add bump/normal map independently.