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Best practice for Modelling Landing gear

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What have others done regarding landing gear on aircraft with complex rigs?  I am finding that, at present, my landing gear consumes far to many polys.  For example, in a model I am working on, I have 19,000 triangles (10k verts) of which over a quarter of those are on the gear and wheels.

I have tried down rezing them a number of different ways, but it would seem there is just no joy in reducing the size without simply lopping large chunks off them.

Here are two pictures, any advice on how to approach shaving some poly's off them would be appreciated. Are the tyres too high? If so, how many polys/tri's should I aim for?

I viewed the BIS A10, but the gear on that aircraft is so simple compared to what I am working on.

wip_gear_080902_1.jpg

wip_gear_080902_2.jpg

Here's a version in ambient occlusion:

wip_gear_080902_3.jpg

I have managed to create a fantastic mesh for what is an incredibly complex aircraft to model, all within a very reasonable polygon budget.  Then, the gear have totally destroyed that.  I have modeled as basic as I could think (except for the tyres) figuring I could put the rest of the detail in the normal map, yet I still come out with a massive polygon ammount.

Thoughts and advice on this greatly appreciated!

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I would greatly simplify the wheels and add the details with normal maps, it looks like that's where all the polys went too. I mean, the wheels are probably going to be part of the model people see the least off, especially when in flight.

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Anytime you have a pole that's not defining any shape, you can get (I think) exactly 2 polies back by eliminating it. The small cylinders of the small suspension arm seem to have a lot more detail than they should, given the level of detail on the other geo, especially of the other cylinders. Detail that doesn't effect the silhouette can be largely faked with normal maps.

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I would greatly simplify the wheels and add the details with normal maps, it looks like that's where all the polys went too. I mean, the wheels are probably going to be part of the model people see the least off, especially when in flight.

It is of course the part you can't see very often. But when you see it, its in high detail (because you're probably standing right next to it).

icemotoboy, if you plan on integrating this model into arma, you will have to massively decrease your polycount. The great maximum should be 15k polys but that only for a single object you may use once in a mission. The polycount to aim for should be between 7k and 10k for plane. Unfortunately you already converted your quads into tris.

The whole tire could be modelled with 6 edge loops around and maybe 10 along the running surface (so that the whole tire looks round from the side), the rest is imo a case for normal maps.

But i'm only an amateur smile_o.gif

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Unfortunately you already converted your quads into tris.

The whole tire could be modelled with 6 edge loops around and maybe 10 along the running surface (so that the whole tire looks round from the side), the rest is imo a case for normal maps.

But i'm only an amateur smile_o.gif

Probably should have stated, I'm modelling in Max and my pipeline is such that everything gets converted to poly's before import into oxygen, then I manually triangulate anything that needs it in there.

Great tips guys, I've managed to get the gear down too 1554 polys. I realise that seems alot for the gear, but I can't see how I can get it down much more without loosing entire sections that are necessary for animating.

I noticed that the right-side rear gear on the A10 is 668 polygons, and mine is now 1554 despite having four wheels on each gear instead of just the one on the A10.

Because of the massive size of this aircraft, like my C130, I've allowed myself to go over the polygon target of 7-10k. I doubt any more than one of these will be required in a mission ever, so I'm thinking I can stretch things to 14k polys.

Here's the reduced version:

wip_gear_080902_4.jpg

Please feel free to let me know any more thoughts, I've managed to reduce the polycount to 1/4 - so thats great news! Extra sets of eyes are very helpful smile_o.gif

Edit: Probably worth noting too, that the BIS A10 has over 13k polys.

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Unnecessary polys are unnecessary wink_o.gif

I find that you could lose more polys and faces without losing too much detail.

wip_gear_080902_4_paintover.jpg

sorry for the sloppy paint over but i'm at work and i only have a touchpad. The red edge loop could be deleted and the yellow could also be deleted and replaced by a normal map. As you will never see this face from the side, it doesnt really matter.

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Really appreciate the feedback! I have made those changes, and they are barely noticable even without the normal map. I will bake full detail into a normal map later to cover it up. I've shaved another 300 polys off the total count doing that!

I find it hard to be totally objective about removing polys, well worth getting the extra set of eyes. I knew it needed to be culled but I didn't have the heart to do it biggrin_o.gif

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Quote[/b] ]Reduced
, but far from optimized  wink_o.gif .

My 50cent input of what i could see...if you continue fixing according to this principle (of low poly game modeling), the model will have way less poly (-15%?).

Same geo so no loss of visual quality...

Golden rule (at least what i do):

-Cilinders: 32-16-8-4 segments as it is a piece of cake to replace them (edge remove tool in modo for example). Very important for lod reducing.

-Keep an overall equal level of detail (wheels segements versus smaller detail..smoothness). Sometimes hard...

optimize.jpg

PS: with what program you work? It hurts my eyes to see all end-caps of the cilinders in that shape wink_o.gif .

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Quote[/b] ]but I didn't have the heart to do it

I have exactly the same problem with my apache. whistle.gif

I was told that separating parts of the mesh can cause Z issues at distance.

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Quote[/b] ]I was told that separating parts of the mesh can cause Z issues at distance.

Maybe, but in most cases that is covered by good res lods. Meaning, by the time you get into problems with seperated objects, the seperated object itself should already be replaced by a solid 'lower and less detailed' poly object.

It is always a heart breaking process, but since it is a game object and not an 3d render object, it needs to perform....so it needs to be as optimized (often = as low as possible be it poly or textures). The higher the ploycount of your object, the less room it gives to leave it unoptimized. Sad but true i think.

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My 50cent input of what i could see...if you continue fixing according to this principle (of low poly game modeling), the model will have way less poly (-15%?).

Same geo so no loss of visual quality...

PS: with what program you work? It hurts my eyes to see all end-caps of the cilinders in that shape  wink_o.gif .

Thanks DaSquade! I'll do some more work as suggested in your image.  I noticed that was how BIS endcaps were done but hadn't prioritized doing it myself.  I'm using 3ds Max 9, and Maya 8, for my modelling and baking of textures.

Will post some updated screens once done, thanks guys - now I will actually have enough polygons spare to model the rest.  When I show the whole model, you'll understand why polygons were a problem.  It's not a typical shape so has been very hard to reduce polys.  The C130 was a piece of cake compared to this!

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