Cineversity

Hi

Does anyone know if the issues of rendering displacements in C4D using RGB (XYZTangent) vector displacement maps created in Mudbox and zBrush still occur in C4D R16? If it works, can someone please show me the settings that I should use in the Displacement dialogue box?

Thanks

Hi Dmaxman,

Do you have a small example? I’m happy to check the file here and explore what could work, No promises, though.

If that was a problem before, did you got in touch with the support?

All the best

Sassi

Thanks Sassi

I’ll put together a file in Mudbox and send screenshots of what it looks like in Mudbox, plus the rendered obj with displacements rendered in Maya and the Cinema 4D file.
I’m not that hopeful though…

Might take a while…

Thanks for the efforts, Dmaxman, please keep it small, so it is easy to test for me :o)

If I can’t get anything - the files certainly will help for any further step.

Have a good one

Sassi

OK Dr Sassi here you go.

Please download the file from here:
https://www.yousendit.com/download/ZUcwZUNvQTY5NVVYRHNUQw

Sorry, because of the 32 bit vector displacement maps the zip size is 90 MB

I have supplied the R16 file that I can’t get to work, the hi res OBJ mesh and the Low res OBJ mesh that I’ve applied the displacement to, plus two vector displacement maps - An absolute tangent that I’ve tried in Maya and C4D and an Object vector map as an alternative.

I’ve included a Maya render (Head_test3_Maya_displacement.tga) using the low res OBJ and the absolute tangent vector map from Mudbox - As you can see it’s almost perfect despite the displacement map being low res.

Sadly, all my attempts with C4D are unusable… but hopefully you’ll be able to work out a solution or at least tell me what the issue is. I suspect that vector displacement maps in C4D haven’t been implemented using the same standard as Mudbox and Maya.

Thanks

Thanks for the file, Dmaxman, I will check if I can find a solution, but again—no promises ;o)

First thing in the morning. For now -it’s past mid-night, time to slow down a little bit.

Cheers

Sassi

No worries.

I think it will take a while to get to the bottom of. I had to stop using C4D sculpting because of this issue (vector maps created in C4D had render issues even in C4D so it would be good to find a solution eventually.

Cheers
Chris

Hi Dmaxman,

Here are my observations, I just think that the object pass has the Z or Blue values inverted. Instead of negative one there is a positive one and vice versa. As C4D has no tools to invert 32bit-float/c image, perhaps you might try it in NUKE or similar useful apps. My recommendation is here to use OpenEXR all the way. Not only for smaller file-sizes ;o)

If there is any option to flip that value in the authoring app for that file, that would help. I have also played with some settings in SPD, but these are minor observations and I think not worth to discuss, as long as the file produces wrong results. Please note that most application invert an image by turning 0 into 1 and 1 into 0, which “inverts” the image around 0.5. Which would destroy the information for the use here. The proper way would be that 0 stays zero, but +1 become -1 and vice versa.

My settings BTW were between 1.5 to 0.5 cm for the displacement, 3.0cm seemed to distort the results too much and lead to too large displacements.

I checked the file in NUKE, and the tiff files have negative values. I’m not used to use these for 32bit/c anymore as they are super large.

I have attached one of my “tools” to explore the file, after split it up in R+G+B, with some other layers, you can then adjust each channel to a certain degree, and see what each one did.  All tools and options I tried have failed, perhaps an image with -1 multiplied would help to naturally flip the values. But C4D clips then. Other trials didn’t lead to better results.

My suggestion, the link of your file should be send to the support. The little Horn on the left side (his right side) indicates the z direction for me, as an example. Perhaps it could lead to three check-boxes in the interface to flip the channel information (Not the PSD invert stuff)

All the best

Sassi