Zbrush Zmapper Bump Map integration:Technical
polycounter lvl 18
Does anyone know how zmapper integrates a bump map into the zmapper integration. I don't mean the actual process in the plugin.. but how? Does it use the high gen model and places the bump map untop and then creates a normal map. Or does it wait until after the normal map is created internally and then integrates the bumpmap into the normal map texture.
In otherwords, does it integrate them when its 3d or 2d?
To better explain this question. I cant get the detail I need with my current highest subd level. So I wanted to use a bumpmap to capture this extra detail. However, from what is displayed when I use the bump map shader untop of the normal map, its still trying to morph the underlining polyons (which I have mentioned isnt at a high enough sub d level to show smoothly). So, if zmapper creates the integration based on the sub d level versus the bump maps resolution, I will come out with a crappy normal map. if it howevers merges them based on pixel depth, then I should be able to capture the detail the bump map provides.
In otherwords, does it integrate them when its 3d or 2d?
To better explain this question. I cant get the detail I need with my current highest subd level. So I wanted to use a bumpmap to capture this extra detail. However, from what is displayed when I use the bump map shader untop of the normal map, its still trying to morph the underlining polyons (which I have mentioned isnt at a high enough sub d level to show smoothly). So, if zmapper creates the integration based on the sub d level versus the bump maps resolution, I will come out with a crappy normal map. if it howevers merges them based on pixel depth, then I should be able to capture the detail the bump map provides.
Replies
probably faster for the majority of fine detail too.
Just run the filter on a greyscale layer, set the layer mode to Overlay, and do Adjust -> Levels -> blue channel set max brightness to 127.
http://boards.polycount.net/showflat.php?Cat=0&Board=3&Number=20539
Why the blue channel only? Again, wont overlay pick up all height/depth differences? (as per strangefate points out). I mean we are talking about a very complex surface here, not a flat plane.
If you look at this exmaple of overlay, I think it helps to show what I mean. Since unless the value is exactly at 127 it willl being to darken or lighten the combined colors.
http://www.sitepoint.com/blogs/2004/08/30/overlay-blending-mode-in-photoshop/
Too much thought..
(curls into ball and sucks thumb)
The blue channel should be 127 so it doesn't affect the baked normals.
You need to darken and/or lighten the red and green channels to alter the direction of the normal on that vector.
It's true that using too many heavily-painted greyscale maps will subtly flatten out the normal map, but if all you want is ultra-fine detail like skin pores, cloth seams and fabric textures, then a greyscale nvidia filtered map done in the method i outlined in my earlier post, will do the job fine.
What other fine detail could you want that needs to be so high-res in zbrush? Wrinkles, pores and high-frequency textures are all fine with the NVidia filter, as long as you're careful about keeping them all constrained to their appropriate areas.
That's how i'd do it, it's much faster than trying to subdivide even more in zbrush, produce huge file sizes or try to bake down bumpmaps in zmapper. just bake your current highest-res mesh and then nvidia filter all the fine detail.
it'd probably be much more straightforward if you just try it yourself instead of trying to learn every single technicality beforehand ... practical experience is worth a lot more than theory.