Hard surface robot character detailing questions

Cortes

Sup fellas. My questions pertain more to general workflow as I'm still a beginner but I'm interested in your opinions.

I have a base robot character created in Max, as you can see here.



He's made up of many separate objects, so when I unwrapped him I could have the maximum focus on detail and uv space, unwrapping each part individually.

My question concerns how to go about detailing the mesh optimally.

Let's take a look at one piece of the model, the body, as you can see here:


Pretty extreme mesh, right? :poly124:

I want to take this mesh and add all sorts of "greebled" hard surface details. Grooves, bolts, plates, that sort of thing. I want to add this sort of detail to most of the other parts of the model like the helmet and the arms.

From what I've learned so far, there are a multitude of ways I could go about it.

1. I could bake a normal map from a high poly also made in Max (the base mesh already has a turbosmooth so it isn't really "low poly" anymore, but for our purposes it is)
2. I could take this mesh into Zbrush and make a high poly that way and then bake normals.

Since I want to learn Zbrush, I am considering the second option more. Trying to add all those chamfered and beveled lines in max onto such a small mesh may give me more trouble than its worth (although I could use floaters) however I keep hearing that hard surface modeling in Zbrush is also pretty hard for a beginner like me (but 3.5 r3 has all these new tasty brushes for that exact purpose though...).

This character isn't for a game, just for animation.

So basically, what would you do in this situation?

cryrid

You could just do the greebles in photoshop, and convert that to a normal map. Plenty of tools there (ndo, xnormal,etc), and it should be really quick to boot

Sean VanGorder

I would personally do the high poly work for something like this in Max. If you are worried about the little details being a little much for you, then just do a basic turbosmoothed high poly of what you have here, bake those normals to get smoothed edges, and then add in all the little details in photoshop using a filter such as nDo.

Cortes

Thanks for the responses!

@Sean_EG The most important detail of what I'm going for are grooves to create the illusion of separate armor plates. I do in fact have nDo and am pleased with what it's capable of, but I'm not sure how to get a "negative" shape in it. Ndo is great for sculpting raised areas, but I haven't figured out how to "cut" in grooves with it into normal. It's probably really easy, but for some reason it hasn't "clicked" yet for me.

@cryrid: Are there any tutorials that explain what you mean? (Racer445's metal painting tutorials are great, by the way) I get the general idea and have painted diffuse maps in photoshop, but again, I'm not sure how the grooves would be created into the normal. Would I just literally paint in dark lines with highlights and then use that to create a normal/bump?

Here's an example of what I mean. My diffuse map for the robot's body with a crappy mspaint paintover, but it gets the idea across:



I'm gettng the impression that this would be easiest with nDo, but again, not sure how to engrave these simple lines in.

Again, thanks!

cryrid

You basically create a height map. 50% gray is flat, black pushes in, white sticks out.
http://img521.imageshack.us/img521/9046/normalmapminitutrf7.jpg has a good example

Cortes

Ah, finally it starts making sense. Thanks for the mini tut!
I'll update this thread with my progress soon.

Sean VanGorder

Also, to get negative shapes in nDo, you should be able to just turn the depth slider to a negative value.

Cortes

Thanks for all the help so far!

What I'm looking to do is what you see on this model:



More specifically, on the blue armored parts underneath this robot's eyes, you can see these indented grooves. That's what I'm trying to get.

Well, I fiddled around in photoshop for awhile, testing different selections and shapes before I reached this result:

normal map:



Earlier, I made grooves with many different layers and "stroked" selections in Photoshop, but they only came out looking llike this:



Sure, the normals worked right, but now I want to get a darker result from the concave grooves, and only got a soft imprint, even with the bump turned up considerably.

After making another grooves layer in photoshop and coloring it in black in the diffuse, I get this test render:



Which is a little better, but I can't tell how much of it is just due to the diffuse which I painted.

Even then, it's still not exactly the result I'm looking for.

What I'm looking for is to make a normal/bump/height map with edges deep enough that they will show up black, shadowy and recessed in the render due to the grooves from the normal map. I made the height map more or less like this (the final had more highlights on the dark edges):



Which I converted to the normal you see above.



Overall, I'm still not satisfied. How will I get those darker recessed grooves without painting it in like I did in the diffuse? Do normal maps not interact with light in the ways I thought they do? I thought the grooves would reflect light and cast shadows from the illusion of extra geometry from the normal.

Lol, I'm still new to all of this, and I appreciate all the help so far.

cryrid

This is what I get when converting your heightmap to a normal map using nvidia's photoshop filter, strength around 15. It is only the normal map applied, no diffuse or anything:


It is possible you may need to invert the green channel of your normal map (I had to)

Cortes

Well, I was using Xnormal's photoshop filters to get the normal map before, which wasn't giving me the dark definition I wanted (I believe I inverted the green channel there as well, so I have no idea why it wasn't working). Now, I converted the height map with nVidia's filter instead, which got results similar to yours, cryrid. After many, many test renders, I've reached this result:



nvidia's normals get me that beveled look I wanted. I also painted in the grooves on the diffuse again to get that extra "pop"
Overall, it's much better, but it could still be improved. Any suggestions are welcome.