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djwaterman
04-08-2014, 07:34 AM
I'm about to embark on a rather massive modelling task, realizing a design for a 700 meter long space craft. Think along the lines of a Pluto station level of detail but without the interiors. I usually model using sub-D modelling, but a subject this big is unlikely to have the kind of close up renders that might require sub-D's, and I'm considering if it might be more economical to use a straight polygon modelling technique.

I'm asking for opinions from modelers that have done big complicated spaceships with high levels of detail, should I go down the path of polygon modeling for this type of subject even though I'm less comfortable going that way? What method is mostly used when making this kind of asset (the 'Galactica' for example)?

bazsa73
04-08-2014, 07:57 AM
That's something I used to think about myself as well but I'm sure at one point I would hit the TAB anyways.

adrian
04-08-2014, 08:16 AM
Well I've modelled the Millennium Falcon which had a massive level of detail and I had a mixture of Sub-Ds (mainly for the cockpit area and the metal plates) and the rest "normal" polygons. So probably 30% Sub-Ds and 70% not. The model is fine unless I do zoom up to it.

CaptainMarlowe
04-09-2014, 12:43 AM
I would say it depends on a lot of things. First, do you plan to have really close views ? I almost never use sub-Ds, and when I create my spaceships I most often rely on polygons only. BUT, it is for my own animation projects and they are adapted for my computer. I mean, if it is aimed at a studio with powerful computers, a render farm and a need for close-ups, then sub-ds for most important details may be interesting.

djwaterman
04-09-2014, 03:19 AM
Ultimately down the line it will be for 8 K resolution and render farms are available, but I doubt we will get as close as you would when shooting a car, it's more like shooting a building I'd imagine. But every thing would need edges of some kind, anything curved needs to look perfectly curved, if I used polys the idea is I should not ever see that.

I look at Tobian's stuff and think Poly's, but then I look at other stuff and think it's gotta be sub-D's. I guess there is no correct answer but I think in productions for the hero ship they probably go sub-D.

geo_n
04-09-2014, 04:08 AM
Organic looking ships probably better to use subd with normal maps and displacement with 3dcoat.
Mechanical looking ships polys with rounder and quadpanels from James Willmont baking those details in is possible.

djwaterman
04-09-2014, 08:49 AM
This is the drop-ship from District 9 (http://giuseppebufalo.com/district-9-dropship#0), it's 100% sub-D as far as I can see tell, and yet it looks like the perfect design for a poly modelling approach. I think I'll go sub-D simply because it's what I know. Did Tobian ever do a modelling tutorial for 3D world? Maybe his methods could change my mind.

Surrealist.
04-09-2014, 09:07 AM
Yeah subds are the way to go for nice looking hard surface stuff.

They are also the tool of choice for displacement mapping.

I recently did a smaller ship all sibds and it was definitely the way to go.

You can also do level of detail with subds which is nice. On a shot by shot basis. If you are doing subds right they make perfect low polygon verions of them selves by turning down the level to 0 for the render in shots that don't need it. You can also subdivide dynamically however I have never been able to get that to work in a practical way in LW.

Greenlaw
04-09-2014, 09:28 AM
I recently built a spaceship for a movie. There were a lot of panels and doors that needed to pop open, roll out, and slide away to reveal all sorts of weaponry, and these panels had to be perfectly form-fitting so I didn't bother with sub-d's. That was partly out of laziness but mostly because I was on a very tight schedule, and trying to model this for sub-d would have taken too much time with little added benefit for animation and rendering.

I think your decision should be based on the forms you're trying to create, and how it will be rigged and animated, and how much time you can budget to create the object. Plus, as noted above, there's no reason to make the entire spaceship as sub-d objects--just use it where it makes sense. Sud-d's won't necessarily make a scene efficient and quickly renderable if you use the technique everywhere.

BTW, the 3rd Powers (http://www.3rdpowers.com/index_store.html) modeling tools reduced my modeling time significantly on this project. The interactive Boolean Tool was especially useful. Highly recommended.

G.

Axis3d
04-09-2014, 09:59 AM
Usuallly, I like the slightly rounded edge you get with sub-d models. It just catches the light a little and makes the render look that much more believeable. But, a while ago I started using the DPkit shader called "Edge", when used on polygonal models gives you the option to round or bevel without having to model it in. It does not work well on close-ups, though. But for distant stuff, works pretty well.

hrgiger
04-09-2014, 11:47 AM
Typically I default to subdivision surfaces as they give you more flexibility in the end as far as resolution at render time but it really depends. Its much easier to stencil and add detail where you need with polygonal surfaces and just requires a little more forethought if you want to use subdivision surfaces. I might even suggest a hybrid approach where you model everything from the beginning with sub-D's in mind and if you ever get to a place where it might be easier or make more sense to work with polygons you can also freeze them at a low subidision level (I would save it out as a copy before hand). Also, there's nothing wrong with mixing an object comprised of both Sub-D and polygon objects together. If you have simpler areas where you can get away with using a minimal number of polygons do that. I would recommend keeping them on separate layers to prevent from subpatching areas that aren't intended to be subpatched.

Lewis
04-09-2014, 01:47 PM
SubD sall the way, where is the fun if you do it easy (non subDs) way ;) ;) :D.

Once i did Arch-Viz building in SubDs just for fun :D.

hrgiger
04-09-2014, 03:29 PM
SubD sall the way, where is the fun if you do it easy (non subDs) way ;) ;) :D.

Once i did Arch-Viz building in SubDs just for fun :D.

Yep, I enjoy working in subdivision surfaces and would rather work with them any day. Here's a screenshot of my space station entry all sub-D's. 185K polygons

121342

hrgiger
04-09-2014, 04:37 PM
Another thing to be aware of DJ is that if you're modeling that ship to scale, you're going to have some precision loss and you won't be able to zoom in as close the farther you go away from the origin. So just keep that in mind if you experience that.

djwaterman
04-09-2014, 11:03 PM
I would perhaps treat it like a large scale miniature, like 20 feet long, that would give me pretty good lighting and texture accuracy while keeping it manageable. I'm gonna go with subdivision and possibly some poly-modelling on separate layers if it makes sense. Poly-modeling is a lost art for me so I'd actually find it challenging. I'm also gonna build the ship up section by section like a real thing, I think that helps to keep it real. I hope at some point I'm safe to show this thing on the forums.