ZBrushCentral

Possible to export grayscale bump map?

ZBrush Usage Questions
#1

Is it possible to export a high-detail grayscale height map from your ZBrush tool the same way you can export your normal maps? I have tried using the displacement maps, but they do not generate enough detail - I am working on a character’s face, and while the displacement map can help with certain muscles, it does not get small details like wrinkles and pores (even when I export out a 4096x displacement map.) I tried using the nVidia Normal Map tools to convert the normal map to a height map, but that didn’t work out either. Mostly I need this export so I can use the bump map in Lightwave, as you can use cavity shader-like effects using gradients (tuned to your bump channel.) Thanks for any help! :slight_smile:

Edit: Nevermind, I didn’t even think about adjusting the levels on my exported alpha. The detail was just, just not immediately visible. Hopefully this will help someone else however :slight_smile:

#2

you can also tell Zbrush to generate a bump map instead of a displacement map. just uncheck “Mode” in the displacement rollout of the tool menu. that will tell Zbrush to generate the map as a bump rather than a displacement.

#3

Actually, Andrew RaZ, that’s not true. Mode only comes into play when you’re rendering a model in ZBrush. If it’s active, then you’ll get rendered displacements. If it’s turned off, the displacement map will be rendered as bump instead. It has nothing at all to do with the calculation of maps, which is why it’s in a separate bank from the elements that do affect map calculation.

There really is no difference between a bump map and a displacement map except for how it’s handled by the rendering engine. If anything, ZBrush will by default give you better quality bump maps because 16 bits of data is always better than 8 bits. Provided, of course, that your rendering engine can handle a 16 bit image in the bump channel. :slight_smile:

There is actually a workflow shown in the Practical Guide where two separate displacement maps are created. One shows only medium resolution details and will be used as a displacement map. The other shows high resolution details and is used as a bump map. The actual settings for calculating both maps are exactly the same. Mode is not on for one and off for the other – it’s ignored completely.

#4

ahhhhhh that makes sense.

thanks for clearing that up before i go on misinforming other people.

#5

It’s been a while since I have used Zbrush and I cannot remember how to take my current model/tool and save it as a grayscale height map. Can someone please refresh my memory how to do this?

Thanks.

#6

maybe this one helps: How to do this? bake a gray bump map in ZB.

:slight_smile:
froyd