Confusion with displacement maps

[simmsimaging]

I am struggling with figuring out a workflow to paint displacement and fine detail bump maps using 3DC. I imported my model for per-pixel painting, painted with relief active, and got a reasonable result in the viewport in 3DC (reasonable for this test anyway ). From there I'm getting a bit lost though: it is very confusing trying to figure out which of the many ways is the correct one for exporting the map.

I have tried exporting displacement maps, and also exporting Depth layers. Each gives a slightly different result - which should it be? Also: do I also need to export a normal map for the finer/finest details, or will 3DC put all the detail into the displacement map?

I'm trying to figure this out by testing in Max/Vray but for some reason the maps I export only seem to create negative (downward)displacement, even though the Vray settings should allow for both directions. Anyone have some direction for me?

Thanks in advance,

Brett

Screen Grab in 3DC:

http://www.screencast.com/users/simmsimaging/folders/Jing/media/536df5c4-8b70-459c-9220-9dc35a8b2c47

Screen grab from Max/Vray:

http://www.screencast.com/users/simmsimaging/folders/Jing/media/18208c5c-80dd-477e-9c28-bc2fa49b3868

[haikalle]

Hi!

I'm not quite sure if I understood the problem but I have blender + Vray and I had to play with Water Level parameter. I can see from your screenshot that your water level is 0.

If your displacement amount is 1 and shift is -0.5 then your water level should be -1.

Should you create only displacement map or both disp + normal it's up to you. There is a way that you can put all layers together and create one nice displacement map.

It's depends what is your worflow. Hope this helps...

[simmsimaging]

Hi!

I'm not quite sure if I understood the problem but I have blender + Vray and I had to play with Water Level parameter. I can see from your screenshot that your water level is 0.

If your displacement amount is 1 and shift is -0.5 then your water level should be -1. Hope this helps.

That seems a bit odd: the water level should be zero unless you want non-displaced areas clipped out. I've never had to adjust it from zero in any other case. I'll try it though - you never know.

b

[haikalle]

Believe me..it's sounding very odd. I asked about this the person who codes the vray export to blender and he said that is how it should work...

And I was like...okey.. But it can work diffrently in max, I don't know.

[simmsimaging]

Hi!

I'm not quite sure if I understood the problem but I have blender + Vray and I had to play with Water Level parameter. I can see from your screenshot that your water level is 0.

If your displacement amount is 1 and shift is -0.5 then your water level should be -1.

Should you create only displacement map or both disp + normal it's up to you. There is a way that you can put all layers together and create one nice displacement map.

It's depends what is your worflow. Hope this helps...

I gave the water level thing a try - it didn't work. Just made the problem a bit different. I think that adjusting the displacement amount up more helped, but the negative displacement went really deep before the positive showed up properely. Something is not right with the greyscale values I think, but I guess further experimentation with a simpler shape is in order.

You mention that there are options for making either disp and normal, or just one depending on workflow: what I'm trying to do is figure out what the workflow should be for best and simplest result. Can you, or someone, suggest a clear workflow that I can try? I don't really care which way I do it, I just want some way of getting the results back to Max/Vray

Thanks again.

b

[haikalle]

Hi!

That's bad it didn't work. how Does your displacement looks like? Is grey zero level and Can you see dark and light grey? There is a bug in 3.1.24 that you

can't merge object into scene. If you have ealier version use that for now, until Andrew is making a update. I can make some video tutorials (not spoken, english bad)

if you want. But it should be relative easy to make those maps. Just merge your object and then choose from menu Texture -> Export and choose the map you want. That's the

most easiest way.

[simmsimaging]

Hi!

That's bad it didn't work. how Does your displacement looks like? Is grey zero level and Can you see dark and light grey? There is a bug in 3.1.24 that you

can't merge object into scene. If you have ealier version use that for now, until Andrew is making a update. I can make some video tutorials (not spoken, english bad)

if you want. But it should be relative easy to make those maps. Just merge your object and then choose from menu Texture -> Export and choose the map you want. That's the

most easiest way.

The map does have black/white values - I think the issue might be related to gamma. Not sure which way to set the gamma on the map yet, might be 2.2, might be 1.0, have to figure that out.

In terms of exporting the maps, I can see that the process can be simple, but it's the choice of options that make it complex.

Let's say that I imported a medium res mesh and just did per-pixel-painting to sculpt some fine/super-fine details in the shape: these things are still confusing for me, hopefully you can shed some light on it :

1) export "Displacement Map Current Layers" (or visible if I want to leave some painted bits out) or "Export Depth Layers"? It looked to me like each of these options produced a different result.

2) When I do that how do I determine if I need a normal map as well? I assume like Zbrush that 3DC puts the finer details in a normal map, so how do I know whether or not I need one, or do you always have to generate both?

3) Assuming I need a normal map, which would be a good choice - low poly, mid-poly, or layer-0 based? Not even sure what layer-0 based means?

For now I think I will have to go back to Zbrush for this stuff, but I'd really like to consolidate the workflow to 3DC if possible.

Thanks again for the help.

b

[haikalle]

Hi!

1) I'm not quite sure...but I think that when your model ready, you should use "export displacement" options. Use "export depth"

when you want to transfer your maps from one model to other one.

2) If you use a renderer program. It takes much longer time to render displacement map that it does normal maps. You already might know this. It takes longer time for Displacement map because it actually moves point positions

on the surface. Normal maps dosen't it only moves normals on the surface. So if you have only very small details on the surface then normal map is enough. with big details use displacement map. You can use only displacement map if

you want. But in some cases your render time will be like 30-50min when using normal + disp would give only 10min. So just test which is the best way for you.

3) I don't know about these. It seems that they create the same map. Maybe someone can explain this.

I hope you can get your settings ok soon...

[simmsimaging]

Hi!

1) I'm not quite sure...but I think that when your model ready, you should use "export displacement" options. Use "export depth"

when you want to transfer your maps from one model to other one.

2) If you use a renderer program. It takes much longer time to render displacement map that it does normal maps. You already might know this. It takes longer time for Displacement map because it actually moves point positions

on the surface. Normal maps dosen't it only moves normals on the surface. So if you have only very small details on the surface then normal map is enough. with big details use displacement map. You can use only displacement map if

you want. But in some cases your render time will be like 30-50min when using normal + disp would give only 10min. So just test which is the best way for you.

3) I don't know about these. It seems that they create the same map. Maybe someone can explain this.

I hope you can get your settings ok soon...

Thanks - I'll hope that Andrew or a 3DC guru can answer as well

Regarding question 2: I do know the difference between a normal and displacement map, but what I don't know is how to tell which one the details get transferred to when 3DC converts the hi-res sculpt/painted details into the two maps. Does some go to displacement, some to normal, or only one or the other depending on how you export etc. I can't find the answers online yet, but maybe I just missed it?

b

[Tony Nemo]

Thanks - I'll hope that Andrew or a 3DC guru can answer as well

Regarding question 2: I do know the difference between a normal and displacement map, but what I don't know is how to tell which one the details get transferred to when 3DC converts the hi-res sculpt/painted details into the two maps. Does some go to displacement, some to normal, or only one or the other depending on how you export etc. I can't find the answers online yet, but maybe I just missed it?

b

The one consideration I would suggest for displacement mapping is whether or not you need to alter the silhouette, as displacement will do this and a normal map will not.

[simmsimaging]

The one consideration I would suggest for displacement mapping is whether or not you need to alter the silhouette, as displacement will do this and a normal map will not.

Sorry - I'm not making myself clear on this.

I am not looking to decide *myself* whether or not to use a displacement map or normal map - what I am trying to figure out is how 3DC decides to allocate detail to one or the other, based on relief map painting I have already done.

That painting does alter the outline of the object in the 3DC viewport, so I assume that it *must* create a displacement map to match that - but if I paint in really fine details does *all* of the detail get transferred to the displacement map, or do you also have to create a normal map to capture that? If so, how do you know or should you always create and use both?

Hope that is more on point. Still hoping for some official clarity on the other questions too pls

b