vray gpu bump wrong direction

V-Ray V-Ray for Cinema 4D Issues
1

Hi all,

I recently noticed that we have to but negative values to the bump amount when using the GPU engine to get the correct results (black is down)
Please find below a screenshot.

Vray_bump1.jpg
Vray_bump1.jpg1334×375 65.9 KB

2

Hello @H_923874

Thank you very much for your time and information. It is classified as a bug (VC4D-1312) and escalated to the Development team for further inspection and resolution.

You can invert the bump map using the invert option in the V-Ray Bitmap, however, this has to be done for each texture separately.​
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3

Hello @H_923874 ,

As I already mentioned here and here, with the release of the latest update of V-Ray for Cinema4D the bug with the inverted bump map has been fixed. You can find more information about the update here. Thanks!​​

4

In 6.2 you still need to invert as you can see in this screen shot here.

image.jpg
image.jpg950×526 145 KB
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5

Hello @seth_richardson ,

Please note that with this update we made the bump map render the same on GPU and CPU. Before the update, the bump map, rendered with V-Ray GPU was inverted when compared to when rendered with CPU. Please check this video where I demonstrate that it is visible that the result is the same now. Keep in mind that depending on the texture that you use you might need to invert it to achieve the desired result, but that should also be needed when rendering with V-Ray CPU. Let me know if you have any further questions.

6

Thank you very much!

7

Hi,

one additional question about this topic. Is there a way or a script available to easily change all bump values to positive numbers (I changed them manually to negative values because of the bug)? I know it would work with abs(x) but I can’t find a way to get the bump amount fields of all materials selected.

Thanks and best regards

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