I'm working on a locomotive model in Carrara and I'm running into some high poly counts. If I need lots of polys for better model fidelity then so be it. The magenta area, the left side of the locomotive frame, on the attached render represents about 6000 polys. Then its duplicated on the right side. I did some extensive rework to get the count down from 8100, picking up some good modeling habits along the way.

The number of tris and n-gons is minimal, I don't necessarily plan on exporting the model for use in another program, but I'd rather have that option, so I'm trying to use safe modeling methods. The drivers (spoked wheels) and counterweights and frame extensions bolted to the back of the frame probably add another 20,000 polys (at least, just guessing). And it's just going to get bigger.

Is this a high count for Carrara? The program seems to handle it so far with no problem. I imagine shading and lighting will affect render time to a greater degree than poly count. Is that a fair assumption? What would be considered the high end, or too many polys? I know a lot depends on the computer.

Thanks

 Hi BL,

When Carrara slows down really depends on your system's memory - but any time you start getting up to 100,000 "real" polygons, sytems tend to slow down a bit. 

I think that you may be setting yourself up for difficulties as the model progress. I'd suggest using a combination of different modeling tricks to keep things under control. For example, the piece you highlighted can easily be created in the Spline modeler yet render with full fidelity. The Spline modeler will create something that is about 1/1000 the memory and poly count yet will render as if it's made up of thousands of polygons.

Another thing I'd suggest is using low poly objects but using Carrara's Subdivision capabilities in the Vertex room. This will yield much smaller file sizes by high definition renders. The subdivision modeler is akin to working with NURBS in other modeling applications.

Ultimately, it's a hobby it sounds like so do what you like. But as long as you are learning to model, there are some other good modeling tricks to pick up. ;-) 

Thanks for the feedback Mark,

Worked thru most of your C6 tutorial at VTC, just starting on C7 tut. I'll try out your tips on the spline modeler for certain, I want the best detail for the least overhead. I don't mind doing something over if I can make it better. And this thing is only about 10% along so I need to be efficient as possible without losing detail.

Thanks again,
Mike

Looks very good so far.  Are you using booleans?

Shawn - No booleans, I don't trust them. Then again, it used to freak me out when I'd accidentally move the drawing plane, now I do it all the time on purpose. Maybe it's time I embrace booleans - where applicable.

Mark-
I actually imported the profile of the locomotive frame into the spline modeler (without all the bolt holes - added those later) then converted it to vertex. And, I'm just guessing here, I probably ended up using too many quads (did I say too many? meant to say WAY too many). At a glance, there's only one tri visible in the attached screen capture from the vertex room (just found another).

The model is supposed to be cast and machined steel, I want the bolt holes to be smoothly round so I've got 32 quads per hole right there (I can see a high fidelity spline model helping here). Then I transition the geometry from the hole to the flat plane of the frame side, and next thing you know I'm drowning in quads.

Am I too hung up on quads and tris? I may never send the model to another program, but I do want to use sound modeling techniques, just in case. While I want model efficiency, it is a complex machine, it will be a big model, a big file. I just can't let it get out of hand. I need to explore the spline modeler, I like the fact you can keep a model simple and jack up the fidelity for rendering.

Can you assign shading domains in the spline modeler?

By the way Mark, I go back to RayDream 2.5 (? or 3, can't remember) and went to Carrara when 1 came out (although I probably upgraded 2 or 3 times before I did more than open the program!). I probably learned more after an hour or two of following your VTC tuts as I did in 15 years on my own. Great tuts, thanks!

Anyway, back to work.
Mike

 Hi Mike,

Thanks for the kind words. Glad the tuts helped out. 

The spline modeler actually assigns shading domains automatically. You an rename them though. Essentially, it's front, back and then one for each side - in this case, the interior of each hole. For a shape like this, I'd do a full line version in Illustrator including the holes and set up my compound holes there and just import it to Carrara. 

A note on triangles vs. quads: The purest will say that you should only use quads. This is true for organic shapes that will be bending like people and animals etc. However, for hard edge shapes, it really doesn't matter. As long as you can crease edges, the flat spots can be either quads or triangles. The only difference is, that every quad adds geometry to your file because of hte extra edge and point. Quads can be  a little easier to work with in the UV editor, though. 

Mark

Well okay then, If tris aren't such a bad thing for a chunk of steel, that alone would make a big difference if I simply chose to go back and edit in the vertex room, I could easily cut the number of polys in half - or more. But I did run through the spline modeler tut last night and want to try a spline version. And I remember the automatic domain names, now that you mention it, because I deleted them and added new ones. Too much 3d, not enough time.

I work in Corel and export to Illustrator. My initial frame profile with just the large holes as a compound shape came into the spline modeler great, so I can go back and add the smaller bolt holes.

I guess you just have to consider each part and pick the most appropriate modeler.

Thanks again,
Mike

Mike;

Quote - I guess you just have to consider each part and pick the most appropriate modeler.

 This is exactly right, and is as true for the guys with multi-million dollar render farms and Maya/3DS/Lightwave as it is with those of us that do this as a hobby.  Sub-division, bump mapping and displacement maps are all tricks that were developed to keep the poly count below the crash and burn memory thresholds (and speed rendering time of course.). For hard edged objects you can't beat the spline modeler.
  Not trying to insult anyone's intelligence, only throwing out ideas..  If I were doing your  loco. I'd probably do most of it in the spline modeler, except for the cab and the backhead of the boiler.  I would probably add the rivets on the smokebox, boiler, and firebox with displacement maps and probably model the staybolts as the 3d equivalent  of NBW castings (nut-bolt washer) with surface replication, but that would be me,  I tend to build 3d models as if they were here in the real world with me, and there are a thousands ways to do it. My other hobby is model railroading so I tend to get a little carried away.
   My standard plug for Mark's classes, you can't beat them, and I've tried most of the classes available on DVD/online.. 
           R/S
Patrick "Sully" Sullivan
 

Sully,

I've only recently come back to model railroading after being away from the hobby for 35 years, and really the only modeling I'll probably do is in 3D. I'm actually more of a reborn railfan. By the way it's a D&RGW K-36.

I've been using this software at work since RayDream but haven't really pushed or immersed myself fully into the program - it's not that hard to model and texture an aerosol can, after all. I've been honing my skills in the vertex modeler, looks like I'll have to dive into the spline modeler just as deeply as long as I can get the same degree of accuracy.

I'll keep posting my progress.

Mike

Nice job so far!

I did a test piece in the spline modeler of a typical section of locomotive frame, importing a compound object saved as Illustrator 8. The front and back faces with bolt holes are perfect, fidelity jacked up to 500. However, I need bolt holes thru the top and bottom faces as well. I duplicated the shader  and threw a texture map into the alpha channel - map had 3 holes (black with white background) which should have showed up where the red arrows indicate - and applied shader to the top face domain. The middle hole came in great, perfectly round so I know the map is oriented and projected correctly, but the 2nd and 3rd holes on either side don't show (or are very, very faint). The top hole has no sides of course, as it doesn't physically exist, but it looks good and I could live with it, if only the other "holes" would show. And I can't see any way to change shading domains short of converting to vertex.

Mike

Used the spline modeler for the locomotive headlamp barrel and reflector, vertex for the side wings, reflector hood and hinge. Very easy and precise, just need more experience. I'm beginning to see the benefits of the spline modeler, and am starting to think about how to model each part in both spline and vertex, rather than just considering vertex. Would still be nice to have more flexibility with spline shader domains.

Mike

 I'm not sure why the other images aren't showing up on the texture map issue. You might also create a hole using the circular layer map tool. You can convert the blank layer shader to a multi-channel and then load in an color in the color channel and black in the alpha channel and you'll have an instantaneous hole. 

Looks great.  I love aging stuff, too.