View Full Version : Help Modeling Car with Subpatches

08-28-2013, 12:09 PM
I've been working with LW on and off as a hobby for something like 10 years. I'm finally trying to make a concerted effort to get better at it, starting with a photorealistic model of my jeep Cherokee. I found a mesh on the internet that's very close, and now I'm trying to tweak it to match my car.

I've been using subpatch to avoid having individual polygons show in the finished model, but I just don't know how to get it to work like I want. Below are some pictures of what I've done so far.

Today I'm pulling my hair out over the side window supports. On the real jeep, they have a nice crease around the windows, while at the same time slowly curving inwards. On my model, I can't seem to get both the crease and the slow curve. In order to get the crease I keep having to use the weight map, but then the polygons are painfully obvious and it's like there's no point to having the subpatches in the first place.

What can I do to fix this? Is there an easy(er) way? Do I need to erase what's there and start over? Any and all suggestions/ideas are welcome! Thank you!!!


08-28-2013, 12:20 PM
Triangle sub-patches? They should be avoided as hell...

You have extremely low-poly model. Any good reasons for this?

08-28-2013, 12:32 PM
The original mesh was imported from Google sketchup, the low-poly count is why I was trying to use subpatches. Is there an alternative to subpatches I should use or do you think it'd be better/faster to build my own model from scratch?

08-28-2013, 12:36 PM
You have geometry ready. Simply join triangles in places that should be joined (merge polys tool). Then split quads it in places that need more smoothness. And will be fine.

08-28-2013, 12:46 PM
I'm sorry. I realize I should probably know this, but how exactly do I split quads? I can't find that command.

08-28-2013, 12:48 PM
Change mode to edges, select 2 edges, press l.
Or you can use mine EasySplit (http://www2.trueart.pl/?URIType=Directory&URI=Products/Plug-Ins/EasySplit), it's all-in-one tool, so you don't have to remember all the tools ;)

08-28-2013, 01:02 PM
I must not be doing it right. Does it matter that I'm using version 9.6.1 ? I can't even seem to get the split polygon tool to work. If I select a polygon, the "Split Polygon" command goes gray and says I need to select points. If I select points, the command seems to just make a bunch of 2 point polys.

I tried using Subdivide, but that just tears holes in the subpatch. Any idea what I'm doing wrong?

08-28-2013, 11:55 PM
As Sensei has said, triangular sub patches will cause quite a few problems. You need to try to convert the triangles to quads by merging polys with shift-z and then adding edge detail where you need it. The being said, it can be a lot more tedious than trying to remodel the object using good poly flow.

I would use the model that you have as a template and model over the top of it, trying to use quads mostly, so that you can make efficient cuts and have a more predictable editing out comes. Simply taking a triangulated mesh from one package and slapping subdivision on it won't quite work the way you want it to, especially with hard surface models, and your weight map is a testament to this.

With quads, you can use supporting edges for hard angles, loop cuts will travel all the way through a loop, where with tris and n-gons they will not, and subdivision is more predictable. These are just a few of the advantages.

08-29-2013, 01:50 AM
What everyone else has said, but also have a look at some wire frames of good car models and you'll get an idea of how many divisions is normally required to get reasonable detail on a car mesh. the mesh you have is more like a low-poly game model, and if you do as has been suggested you won't need weight maps to get clean sharp edges. Definitely use the current mesh as a BG reference, that will help out tons.

Search our car maker friend's blog for wire frames.


08-29-2013, 03:50 AM
Well for polycount it is it looks very good so far BUT for a subPatch/(subDs) car it's too low polycount, you simply have to have more geometry in certain areas to get some details. Also as already mentioned you should fix several areas to remove triangles and have Quads only wherever possible (It's not mandatory to have Quads only on all areas but they perform better in subdivision and rendering/reflections). I also prefer to NOT use weights but solve all with geometry but you'll need more polys to make it good in this case.