A question about correct optimization.

Hayden Zammit

Heya. Was hoping someone could tell me if I'm approaching low poly models in a suitable way.

I'm working on a gun at the moment. I'm doing the low poly for the grip and am wondering about how to correctly optimize. Take a look at the pic and tell me what you think.

The one on the left is 50 or so tris less than the right one, but it clearly doesn't look as clean. Does that matter? Its all tris and quads. the silhouette is the same for both.

Thanks.

Bek

You can optimise more by deleting the middle edges/verts, assuming they don't change the silhouette. (In case that wasn't clear, by the middle edges I mean the single row of edges that runs down the middle of the model. Only the verts that don't change the silhouette. So 4 vertices can be deleted)

Have a read of this: http://tech-artists.org/wiki/Beveling

So you need to minimise the number of verts, and carefully choose where your UV breaks will be, and what faces will be apart of what smoothing groups.

respawnrt

Assuming your grip has some small curvature in the middle (with regard to HP), you can delete that middle loop and the shading from NM will make up for it.The right one looks like a mess !
You could also collapse a few more edges.

Hayden Zammit

Bek - I'm using maya, I think with smoothing groups its either all hard or all soft for Maya. I always just soften em. And if I delete the edge down the middle it'll create n-gons.

Hayden Zammit

Are you guys talking about this loop?

respawnrt

Yeah

MeintevdS

Hayden Zammit wrote: »

Bek - I'm using maya, I think with smoothing groups its either all hard or all soft for Maya. I always just soften em. And if I delete the edge down the middle it'll create n-gons.

Eh? Maybe I'm misunderstanding, but make an edge selection > hold shift down + right click > Soften/Harden Edge.
This way you can have a certain selection being soft edged and rest hard edged. Or the other way around, whatever you're looking for.

Hayden Zammit

MeintevdS - Ah yeah, sorry, I know how to do that. I've just never used hard edges. Soft edges usually gets me what I want.

perna - Not sure what I meant by it not looking clean. I guess I'm just used to high poly modeling, where I stick to quads and try to keep everything nice and even spaced. I'm aiming for somewhere between 3.5-4k tris. You can see the actual gun here: http://www.polycount.com/forum/showthread.php?t=105856

At the moment I'm aiming for it to be a first person gun.

Hayden Zammit

perna - Ah, I see. Alright. I'll aim for around 7k tris. So with that pic I posted, you would just go with the one on the right? I'll see how the bakes look on the more optimized one. If the bakes are okay then I suppose it would be best to go with that, as you said it doesn't matter how clean the mesh is as long as the bakes look right.

I didn't realize console specs were that high.

Hayden Zammit

Yeah, I have modeled the entire gun.

I'm glad I asked this question. Seems I knew nowhere near as much about optimization as I thought I did. I'll go through and try and do it better.

This is the whole low poly at the moment. it's only 2600 tris, so as you suggested I'll add much more.

Hayden Zammit

You have a lot of intersecting shapes now. See about merging it up into a seamless model for the sake of UVs and normal map generation.

Then move the camera so you get the action first person view and add in segments and bevels until the silhouette is all smooth

I didn't think you had to have seamless models. I had planned to just bake down each part separately. Is having a seamless mesh just for convenience purposes? Intersecting geo always seemed easier to model and to keep the tris down.

I'll give it a try though.

Hayden Zammit

You might be focusing too much on mesh-optimization. This isn't the 90s, there's no advantage to extreme optimization. Build to budget, make the mesh clean and easy to work with, easy to texture. Make sure it bakes well, shadows well, that there aren't any harsh transitions between intersecing meshes that may break specular highlights and reflections, etc. If your company gives you a 6k budget, they'll most likely just look at you funny if you deliver at 3k, instead of being impressed.

Ah okay. Yeah, it seems I am focusing on the optimization too much. I'll take another look at it all. Sorry if all these questions are starting to seem pretty basic. I really appreciate the help.

I'm going to try to start merging parts where I can. I doubt I could get the whole thing merged, but reading through a few other threads on the issue, I'm starting to see the benefits of at least trying to get as much merged as I can, even if it does cost a few more polies.

Ace-Angel

Not to mention, alot of them shiny new maps kids like to play with will require a mesh that robust and nice looking, as well simple to work with and be able to carry itself well, as opposed to it being super clean, down to the very small welding of a vertice could lead to issues in the long run.

Hell, even iPhone games try and put a majority of the costs on polies as opposed to textures.

So yep, listen to what Perna's says!

Hayden Zammit

perna - I've been reading up all about intersecting meshes. Would a part like this definately need to be one piece? Its at the back of the gun, in clear view if in first person. One mesh will get rid of the ugliness in the bake where the meshes, intersect right? For less visible parts is it less important to always have a seamless mesh.

I'm glad this has all came up. Shows me how much I have to learn about actual modeling.

Hayden Zammit

going by the above lowpoly, making it seamless would only add about 6 triangles. Kind of pointless to worry about 6 triangles when you're several thousand under budget

I'm going to go over the entire high poly and see what I can do about making as much of it seamless as possible. I have a feeling there's just some parts that will be beyond my skill level, but I'll post back when I've done what I can.

EarthQuake

Your highpoly?

You don't need to make your highpoly watertight. You can do it with your low though, how you construct your high shouldn't have much to do with how you construct your low.

Generally I merge all of the lowpoly bits together as much as I can, except for pieces that would animate or make bakes more complex(complex overlaps etc).

But the high, model it in as many chunks as you need to model efficiently.

Hayden Zammit

Okay, so I thought the high poly had to be seamless as well. I've attached a pic. I thought the point of making both the high and low poly seamless was to get the normal and specular to look better where they would have intersected, like in the second image.

EarthQuake

Hayden Zammit wrote: »

Okay, so I thought the high poly had to be seamless as well. I've attached a pic. I thought the point of making both the high and low poly seamless was to get the normal and specular to look better where they would have intersected, like in the second image.

Try the same with intersecting highpoly and merged lowpoly.

We can get into the aesthetics of merging highpoly meshes, or moreso limiting nasty intersections, but there isn't any technical reason why your high would need to be merged.

Hayden Zammit

With you and Perna having the same avatar pic, I was thinking you two were the same person for a bit there.

I tried what you said, and did a quick test. The result isn't as nice without the merged high poly, but its better than what I thought it would be.

EarthQuake

Hayden Zammit wrote: »

With you and Perna having the same avatar pic, I was thinking you two were the same person for a bit there.

Yeah it confuses me sometimes too, its all part of Per's diabolical plan to confuse as many people as possible.

The result isn't as nice without the merged high poly, but its better than what I thought it would be.

Pretty much.

In the future you can put more though into how parts are intersected. When you start to think about how objects are created in real life you realize its always one of a few things:

1. Two complex shapes will form a solid object. Here it is straight forward, you just want a soft intersection.
2. Two complex shapes, one is cut into the other. Here you can simply "imply" seam/shape lines on one of the objects(you don't have to really cut a big hole into it, a simple beveled inset is usually enough).
3. Two complex shapes, one is bolted to the other. Here the smaller shape will lay flush with the larger shape, and you'll have a bevel on that smaller shape where they butt together.

For original concepts you can vary this up quite a bit for effect.

If any area of a mesh is going to be seen up close, its worth it to think about how you handle the intersections. If its not going to really be seen in detail, you can skip and just do a simple intersection.

image to show what I mean:

Hayden Zammit

So the last example is actually two separate meshes, but you've made an indent on the cube to make it look like they're joined?

And the third example, that's just having the two meshes just touching?

I think I'm starting to get all this. I really do just need to be a bit more observant when I'm modeling.

EarthQuake

Hayden Zammit wrote: »

So the last example is actually two separate meshes, but you've made an indent on the cube to make it look like they're joined?

And the third example, that's just having the two meshes just touching?

Yep, and the first is just a basic intersection, 2nd is a soft intersection.

Hayden Zammit

Well, Perna, EarthQuake, consider me schooled. I'll start practicing this stuff and see how I go with it.