ZBrushCentral

displacement map and normal map

ZBrush Usage Questions
#1

Hi there,

My question is when should I export a displacement map and when should I export a normal map? I have modeled a tree using zspheres and I also added the fine textures. My model had 7 subdivisions. I tried exporting a displacement map b/t subdiv 1 and 7 but I didn’t see much detail so then I exported a dis map b/t subdiv 4 and 7 just to test and I saw much more detail. So I was just wondering could someone give me some tips on exporting a displacement map and normal map together. I remember someone told me once that I should export a displacement map bt subdiv 1 and 5 and then export a normal map bt 5 and 7, why is that, or is that even right?

Thank you,

#2

Remember that when you’re dealing with displacement maps, what you see with your eye is not necessarily what the computer can see. Displacement maps have vastly more shades of gray than can be distinguished by the naked eye. So even though you might not see all the detail that’s there, the computer can still make use of that data to create the correct displacements.

As for what type of map to use, it really depends on your rendering engine and your particular needs. However, you will usually get the best overall results by creating a normal map of the highest couple/few levels of detail, deleting those higher levels, then going to level 1 to restore your base mesh and create a displacement map. You then apply both maps in your renderer. The displacement map will have only the medium resolution details – the stuff that typically visibly alters the silhouette of the model. The normal map has the high resolution details – stuff that is too small to have a visible effect on the silhouette. The result of this will normally be a much faster render without sacrificing any visual quality.

#3

Thank you so much aurick.

This totally clear things up for me. If I have any more questions I’ll post it here or I’ll PM you if you don’t mind.

#4

I just recently found out about 32 bit displacement map, my questions is do I need to use geometry approximation for that in maya? Or do i just import the low poly mesh and apply the 32 bit displacement map? Also, if I use that I don’t need to export a normal map right or should I export a normal map of the higher rez and 32 bit displacement for the lower rez?

Thank you!