RT GPU: Bump from bitmap is hardly visible

[kosso_olli]

Hello,
I am currently testing RT GPU for my workflow, as it got considerably faster since the last releases. On two Titans it is great fun so far, apart from some problems.
What is bugging me most is the very limited bump mapping on GPU. I can only use bitmaps, but that has it's problems, too. It seems that I have to crank up the bump multiplier using a value of x5 to match the results from Vray Adv. Attached is a screenshot, and the bump effect with exactly the same value is hardly visible. If I make it around 5 times as stron on GPU, it's closer to the intended effect.

Regards

Oliver

[Donfarese]

Bump maps on GPU still don't work right, or reflection maps. Also I noticed that if you set the maps blur to something really low or say Zero, it really comes out messed up. Make sure there is not reduction in blure or other output settings on that map and try again. also make sure you use straight bitmap in bumpmap slot, I've noticed issues with vraycolor2bump.

[kosso_olli]

Thanks for the info. But it is exactly that: A plain bitmap in the bump slot, blur set to 1.0

[savage309]

Can you check if your bitmap textures are not resized and that you are using 32bit textures (RT settings tab). If you can share the scene it would help as well.
RT GPU is completely different code base / engine to Adv. Bump with bitmaps works, but it is true that it doesn't match V-Ray Adv results (RT CPU doesn't match them is some cases as well).

[kosso_olli]

Blagovest, I tried your tip. But it doesn't help, so I sent the scene.

Regards

Oliver

[kosso_olli]

Never got any feedback on this. What where the results after looking at my scene?

[savage309]

Hm, strange. I have replied you on your mail a few days after you have send the scene. Did you got my response ?

Best,
Blago.

[kosso_olli]

Indeed, you did. Sorry for the inconvenience. But has the bug been solved?

[savage309]

We have a bunch of improvement with bump maps in 3.40, but I don't think the result that you were expecting is quite there.
RT and Adv being two different render engines happens to have a differences from time to time.