Zbrush vector diagnostic

Started by Ashley, December 08, 2014, 07:34:26 AM

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Ashley

Hi,

I'm after a step by step guide on how to setup the zbrush vector diagnostic to render in terragen?
Any advise greatly appreciated :-)

Cheers

j meyer

Here you can find something:
http://www.planetside.co.uk/forums/index.php/topic,16110.0.html

And btw the search engine is there for you too.

Ashley

Thanks j meyer,

I was unable to recreate your vector diagnostic results.

here are my steps;
- create obj reader and load diagnostic obj
- create a vector map shader and an image map shader connected to it function
- load diagnostic exr and set color to linear
- I also move the obj up in Y to avoid the planet terrain

When I render I don't get any displacement. The vector displacement shader I have connected under the shader context.
Not sure what I am missing?

Oshyan

Displacement only works on terrain, not objects (unless Raytrace Objects is turned off, but render quality is then reduced, and displacement results are often not great). Terragen can however handle very high poly objects fairly well, so you can try baking the detail into geometry and exporting as OBJ, then loading into TG.

- oshyan

Ashley

#4
Thanks Oshyan,
I'll give your method a go for my regular workflow.

However what I'm trying to do here is diagnose what 'flavor' of vector displacement terragen likes.
The vector diagnostic is exported from zbrush. Once I know that my goal is to be able to transfer zbrush sculpts to terragen via vector maps and extend, erode, enhance in TG.

I am using the latest build of TG3, but I remember getting vector results from TG2 free version. Has anything drastically changed?
So far through all the posts on this forum I've had time to read through everyone has a different approach to vector displacement, is there not a consistent method?

Dune

I didn't understand what you meant by vector diagnostic, but my experience with vdisp maps is that the rotation and attachment sometimes needs adjustment. So, from the image map, convert the colors to scalars and attach to a build vector (perhaps through a rotate Y vector), but check out which color goes where and what rotation is needed. Once you have it working it works for every map.

j meyer

#6
Ashley - read the thread and you'll find the info you need.
            In short you have to use no.3 in ZB.


Oshyan - ZB diagnostic is a way to determine which settings to use
             in ZB to make Vdisp work flawless in other software.
             Apparently they don't use the same approach in every app
             unfortunately.

Dune

Oshyan may know, but I didn't. Now we both do  ;) Thanks.

Ashley

Thanks j meyer, I've read that thread over and over and over, my results...

- Using 3 as suggested worked but I am not able to view the vector diagnostic as you did, my goal is to be able to debug with the diagnostic test.

- My vector disp setup that worked flawlessly is to use an image map going into the function of a vector displacement shader, thats it.
I didn't need to flip colors, rebuild vectors, rotate vectors etc.

I am genuinely curious to know what benefits there may be using other methods, If any are willing, it would be great to see a tgd setup of what has been described.

Thanks for all the replies, it is appreciated. As it stands I feel TG just doesn't support the workflow I have in mind.


TheBadger

QuoteAs it stands I feel TG just doesn't support the workflow I have in mind

Can you describe precisely what you want to do? Not the test you are trying to make, but the rest?
It has been eaten.

Oshyan

Yes, it would be good to know what the end goal is. Nothing major should have changed in regard to Vdisp support from TG2, as far as I recall.

- Oshyan

TheBadger

#11
Quote- My vector disp setup that worked flawlessly is to use an image map going into the function of a vector displacement shader, thats it.
I didn't need to flip colors, rebuild vectors, rotate vectors etc.

Yes, thats right. You can use a vector disp and a vector displacement shader alone easily. so long as the vector map is EXR. This is the best/fastest/easiest way in my opinion because there should be no need to manipulate the terrain with other functions, since the terrain would already be just the way you made it (wanted it to look like) in Z or mud. The big thread (16 pages I think it was) is not the only thread on this topic. Some of the info is scattered in the forum. But to summarize that, yes, just use 2 nodes. This is a good way. Though you seem to know it now already based on the quote.

I think the only problem here is that we don't understand the exact problem you are having is all. But if it is only testing Z the way J did. I can't help with that. I use Mudbox and it does not work the exact same way. But I have been through this workflow a lot. It works pretty well. Though there are a few limits, but those are in Z and Mud, not TG so much.

Quoteit would be great to see a tgd setup of what has been described.

Since you use Z-brush, your in luck. "chris_x422" posted files from his own work. He included the Z-brush maps, I believe. Not sure about the TGD. But he posted finished images. So with the files and the images he posted, you should be able to reconstruct what he did. Than look at the images he posted if they are the same, than you are doing it the way he does. He is a pro by the way ( I think that should matter) he worked on some big films. I mean, his workflow is proven.

chris_x422 also posted a tut based on his work on the film "Snow White and the Huntsman". In which is shows how he used TG and Z to make a scene for the film. Its here some place, I am sure one of us can find it for you if you like.

My point is this does work. ITs just hard to sort through and there are some tech limits.

http://www.planetside.co.uk/forums/index.php/topic,16110.120.html scroll down a bit.
This is the first post by chris in the big thread. Read forward from there and you will run into his files. Use those to test your own thinking.
It has been eaten.

j meyer

Ashley - I don't know of a way to debug with the diagnostic files.
            As The Badger said your 2 node setup should work.
            The other ways with functions and so on are not necessary,
            we were just testing things.
            Trying with Chris' stuff is a good suggestion,too.
            The rotate vector stuff at the end of the thread is for rotating
            the Vdisp in TG.Someone wanted to distribute various versions
            with different sizes and rotation,if remember correct.
           

Ashley

Cheers peeps,

So if there isn't a way to use the  diagnostic in TG then it can be a process of elimination, only 48 options  :'(
Good to hear that the simple VD setup is the best, although I still get varied results. But as was pointed out, this is likely my settings in the apps I use to generate the maps with.

I wanted to use the vd diagnostic to at least check that my TG setup was correct, and therefore narrow down the list of possible issues with the generation of VD from other apps.
But I think heightfeilds will be a better approach.

Basically I was trying to use VD to blend sculpted terrain, generated terrain etc inside TG.
After doing some more reading, it looks like heightfields are better suited to this task. As I found out have more erosion options in TG, are super easy to setup and tune, as well as being able to blend with DEMs.

However I'm going to look through chris_x422 tuts and files.

Seriously the TG forums are the best, thank you so much for the assistance.