Hi guys,

Just did a low poly beetle and going to bring to Zbrush. I never used normal map before and want to give it a try.(tri count is 5164)

1. The beetle has lots of floating parts, how will that work with normal maps? Do I generate it at once or separately?
2.It's sort of hard surface thing, how do I make clean masks in Zbrush?
3. Is it better to extrude than put floating parts? I was worried that once smoothed, it is going to look mushy.

Thank your input and C&C.
Concept by Hideyoshi

1. Floating bits are fine, you render them the same as you would anything else.
2. There is absolutly no reason you would want to do these types of hard surface modeling in zbrush. You can do everything you want in whatever 3d app you're using with standard sub-d methods, trying to do this in zbrush will be an uneeded headache for you.
3. Somethings with complicated shapes it can be better to have a lot of floating stuff, not every thing needs to be a solid mesh, and you should try to stay away from making solid meshes as much as posible, for simplicity sake. You dont want to get to a point where your cage just has way more detail than it needs to because you had to cut in all these little shapes and everything, its a waste of time.

i second what EQ says...especially since it seems as though you have a good grasp on modeling anyways.

Nothing to add that wasn't said.

I think you did a good job of creating the concept. maybe could add those pointy parts at back of feet.

You might wanna try baking detail from a higher poly mesh or making a normal from a hipoly mesh.

Thank you guys. The concept is by Hideyoshi, not me.
I still have some parts that I extruded, so I will go back and fix that. Another question, how do you sculpt perfect shaped indention like circle or curves on high poly in Maya? I know in Zbrush you will have alpha masks.
Also, if you add detail mesh on the high poly, like nails, will it be baked too?

I did a little bit nurbs before I got into detail modeling on this one. But I am not very good with nurbs.

you can really do anything with normal maps- just note that this is the point in learning 3d where you are really going to learn there are many different ways of achieving many different result. Really the biggest thing is decide on an end result, and start experimenting with all the different approaches to achieving that result. I can tell you right now that normal maps are sorty jankity and they take some fineness. its by no means some revolutionary new process that will make your models better no matter what.

with that said, its my opinion that you want to use your modeling package for the highpoly mechanical/hard details, and z brush for anything soft/organic.

I simply find I can knock out highpoly mechanical detail faster and have it look more like actual machined parts, where as sculpting programs (zbrush/mudbox) are super fast and great for fleshing out the fleshy bits. thats not to say you can use zbursh for mechanical parts, but you might find that you`ll result with less of a headache if you take the direct route of making the exact surfaces, rather than muddeling about in a sculpting program.

with that said lets take a look at your lowpoly cage.
Its a very nice and clean mesh. Looks to be all quads which will benefit you nicely as its rez-ed up for highpoly scultping action. I dont know how other packages generate normal maps, but I imagine its only a slightly different process than 3dsmax so I image theres whats called a "Cage" for any other process.

This cage is generated from the lowpoly to encompass the highpoly and capture the highpoly data onto the lowpolies UV`s.
^^^I know this is a "DUH" but I`m tryin to be complete

With that said, anything penetrating the cage will confuse the ray cast information being generated. SO- Generally when your doing a bake, its nice to make things easy on yourself and bake things out, bit by bit, then compile all your pieces later.

Another huge thing is smoothing groups:

the smoothing groups you put onto lowpoly mesh will show up in your normal maps when you do a bake. This means you need to have as clean of smoothing on your lowpoly as possible. If you have a hard smoothing group seam, make shure your okay with incorporating that into your highpoly design.

One thing you can do to sort of bypass this is take your low poly with fully unwrapped UV`s, and smooth it so it minimizes your ugly smoothing and bake the highpoly to that mesh instead of your original lowpoly mesh. The UV borders will stay intact.

To awnser your extruded, vs. detached it really doesnt matter, you just have to figure out what appeals best to you as a final result. For example the section with the danger stripe rectangles on the side. Right now its going to look perfect with the silhouette BUT- your locked into surface information with the smoothing groups on there. you can make that whole surface one smoothing group, and it`ll allow you to do fancy things like make chamfered edged for the danger stripe boxes, maybe some angular bolts- etc. BUT! the smoothing groups from the lowpoly will override any cool normals with a nasty smoothing group. SO to fix this, instead of making those boxes come straight out you can inset them a bit, making the surface less extreme, thus softening the ugly smoothing groups- BUT! your model will now longer have the desired effect for its silhouette.

This is my take on normal maps and a glipse into my process a bit, but I know theres many other ways to get there. really Its probably best to make the highpoly first, then the lowpoly second, that way your allowed to be as creative as possible and with little restriction to the lowpoly. Modeling a highpoly mesh however without understanding of how the bake process works would be time wasted.

SO- to be honest, your mesh probably wont be able to take full advantage of what normal maps do, mainly because youved already nailed down the form, and surface properties quite a bit. I know I said it would be time wasted earlier to start with a highpoly mesh, when you have never baked normals before, but In this case I think you ed be okay especially if you stuck with the concept. Just note that you don`t want to make any highpoly details that are going to give you a headache when you try and model a lowpoly mesh keeping in mind smoothing groups and UV seams


So you see its very much about experimenting, and deciding on which road, best leads to rome.

Yeah, I heard UV seams are very obvious in normal maps. It's a great tutorial piece you wrote here, appreciated.Also checked out your amazing website, very impressed.

The reason I made the low poly first is that my teacher told me to. Do I UV it before I make hi-poly? Also do I smooth the edge normals before the hi-poly?

Sorry so many questions, school just doens't teach all you need.

Unwrapping generally takes place once the low, and the high mesh is completed and you want to start baking. For your case now I can think of two options.

1) unwrap the mesh you have now and save a copy of it. Then, start detailing the unwraped mesh. It doesn't matter if you destroy the uv`s because the uvs on the highpoly are never used- Once you finish detailing- drop the lowpoly version ontop of the high, and start seperating out the seperate pieces, and start baking it piece by piece- then assemble all your bakes in photoshop.

2)dont do any unwrapping (for now) at all and just keep detailing the mesh you have. Once thats done, build a lowpoly mesh over this highpoly (now you have the advantage of knowing what forms you`ll need to represent. this takes all the guess work out of modeling the lowpoly. Unwrap the lowpoly- seperate the pieces- bake.

Of course you can mix both of these steps, unwrap now- model the high, drop the low on the high, and adjust it, add loops where needed, remove loops where needed, (make sure to fix your uvs) then bake.

"Also do I smooth the edge normals before the hi-poly?"

I`m not quite sure what you mean, but if your asking at what stage the smoothing groups need to be finalized, they
need to be finished before you bake your normal map onto the low poly.

what I mean is the Normals/ soften edges.(or harden edges) which makes the mesh not so facet looking

your going to need to define your soft, and hard edges for both the highpoly mesh, and the low poly. just make sure you have your edges set to soft, or hard on both the high and low before you bake. you can either apply them as you go, or apply it all when you finish your model. just figure what works best for you, and the project.

Hey, cool design. Nice modeling. As for creating normal maps I use Z Mapper. I haven't had any problems with the uv seams at all. The only thing is that you have to generate each normal map for each separate layers now and not just one mesh anymore. I never put hard surfaces into Z Brush to sculpt before but I think there is a option to keep everything hard edge. Here is an example of a mechanical character hard surface. Good luck. [img]/images/graemlins/smile.gif[/img]
link: http://www.taehoonoh.com/

Great link, dan. Thanks.

My first normal mapped project! So I worked more on it and doing normal and specular now. Trying to convert normal to specular (based on a tutorial found on modwiki). I admit that didn;t do a perfect job unwrapping because the final crunch time now for me.

Couple questions:

I used 1024 for texture, normal looks a little pixelated, what's the best to clean it up? or is 2048 is the new standards for next gen now?

How can I convert textures on to normal map? for example, rusty metal texture. Do I just lay them on top of each other?

Again, C&C welcome.

"I used 1024 for texture, normal looks a little pixelated, what's the best to clean it up? or is 2048 is the new standards for next gen now?"

2048 is standard for certain objects. you wouldn't put a 2048 on a park bench for example. Its all about context. as far as the pixelation, post the maps so we can see whats going on. its possible your render settings aren't optimized. Also if your doing a vehicle for a fps a 2048 is adequate.



"How can I convert textures on to normal map? for example, rusty metal texture. Do I just lay them on top of each other?"

yes. you don't want to even think about modeling the bumpy noise that a rusty metal would create. Its standard practice to lay bump maps on top of your normal map.
bump map = light map generated off of 2d information
normal map = light map generated off of 3d information (more robust)

you can easily take the normal map and drop a bump map on top of it, BUT be sure and go into your levels window, select the blue channel, and set it to 128 grey before you make it overlay. this takes out any blue that would tweak the normal map in a way you dont want it to.

problem is less obvious when not zoom in or use blin.

yeah normal maps aren't magic and while you will be able to get a lot from your high poly stuff that really sticks out and will change the sillouette (sp) of your model needs to be in the low poly mesh as well.

I really dig the high poly for this though.

Another question:

How to render AO in highpoy? I only UV the low poly

same as your normal map. render to texture...

I baked them part by part for normals, should I do another AO on all the parts together and do an overlay?

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I baked them part by part for normals, should I do another AO on all the parts together and do an overlay?

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yeah that should work, your high polys looking great so do what you can to get the most out of it for the low! [img]/images/graemlins/laugh.gif[/img]

hi, guys,

After I bake normal map part by part, they look Ok. But when I start to put pieces to one map and assign them , normal map looks inverted. I tried to invert G or R channel, didnt work. What can I do?

Just fixed it. I didn't use tangent normal for the bump slot. Hoory!

ooh- what version of max are you running>?

Looks cool, would like more images though.

I'm using maya. I really need to get better with MAX [img]/images/graemlins/mad.gif[/img]

a qucik workaround is to autogenerate UVs for the high poly and bake AO to a texture. then apply AO to an unlit shader (like surface shader) and then make a diffuse bake from highpoly to lowpoly. (older maya version like <=7.0)

if you got maya 8.5 (maybe 8.0 :S) you can directly bake a highpoly AO to a lowpoly UV space through the new "transfer maps" option from the rendering menus.