@rspierenburg said:

Is there any chance the wall in the mirror has a reversed face? Could that cause the issue?

Good point! Indeed it was reversed, but fixing it didn't solve the problem. It still looks bad. For now, the solution I found for this, was to render the entire image, then reverse bump map and use render region to render only the mirror, and altough this does not fix the problem I can't even see why it happens to begin with, so it looks like I'm stuck with this solution.

Hello there,

I have a problem with bump maps in V-ray 4.0 for SU. As you can see in the image bellow, the reflected wall on the mirror, have the bump map inverted, compared to the wall directly in camera sight to the left, or bellow the mirror.

I have created this tiles material back in V-ray for sketchup version 3.4, in that version I have also observed this effect and almost died inside because I needed to deliver that render in 3 hours and it wasn't looking great there... Fortunately on V-ray 3.4 this effect was only present in the prepass part of the rendering process, or if I rendered with V-ray Interactive. Rendering with buckets would fix the bump map after the actual "rendering" pass. But no luck in V-ray Next, as it gets to the final rendered image still whith the inverted bump map. That only happens on reflections though.

Do anyone have any idea about what may be causing this, and how I can fix it?

Many thanks in advance.

I have this scene on the "garden" of a house, with a small pool and I went on to make a water material for the pool with some waves effect, for this I used a "noise legacy" on the displacement map, it was rendering fine at first on my render tests, but now after I'm finished with the scene it is simply acting weird, as some buckets simply won't render and they're all on the contact between the water plane and the pool wall, as can be seen on the image attached.
I tried elevating the water plane so it wouldn't contact with the pool border but it didn't work, tried deleting the plane and creating another one, applied the material and same result, tried making another water material and deleting the first one, still same thing;
I then went on to use one of the default water materials that came with Vray and it rendered at first without displacement but for some reason the result was a dark liquid even tough it rendered very clear on the preview image, went on to apply displacement on it, it didn't give me black buckets but still gave me the dark water and the displacement effect was almost not visible because for some reason it didn't create reflections on the waves.
I also tried importing my scene on a new sketchup file, reseting vray render settings, changing resolution and removing some render elements, when trying progressive rendering it looked like it wouldn't make black spots on the image but after like 23% was rendered it was taking forever to go up 1% on the render progress so I gave up on it, what bugs me most it that it only happens if I have displacement applied on the material but I have at least 3 other materials with displacement on the scene and none of those makes black buckets, I thought it was because the water was a plane and not a solid object and made a thin rectangle-like solid it still gave me black buckets and then if that was the problem my grass should also have those problems since it's also a plane not a solid. Anyways on this angle you can only see the water and the barbecue thing as materials with displacement.

Also I have tried different bucket sizes starting with 32, then 16, the attached image had a bucket size of 8.

Anyone know what might be causing the problem?