Low poly - high poly - how many polys are enough?
XoechZ
Posts: 1,102
Hello!
When I create items like clothes, I always do it with box modeling. Starting from a very low poly object like a simple cube, refining and adding geometry until it is a smooth fitting pantie (or whatever).
The problem is that I am never sure when it is enough geometry. I guess 100.000 polygons for a small panty are way too much, but 200 polygons for a whole suit are not enough.
So, how long is an object called low poly, when does it enter the high poly stage? How do you decide that there are enough polygons in the mesh?
Comments
That depends on what techniques you want to use when sculpting wrinkles and texturing it. Do you prefer to add wrinkles using sculpting the mesh, or using a displacement map? These two methods are both found in the DAZ store depending on artist preference. A mesh that will be sculpted with displacement can be fairly low in polygon count (in which case a pair of trousers can be around 10k polys) whereas one with a sculpted mesh needs to be higher in poly count (in which case it may be nearer 50 or 60k).
Both of these are valid techniques with advantages and disadvantages. A lower poly mesh with displacement maps can appear higher detail even than a sculpted model; a higher poly mesh is much more accepting of shader-only texturing, which many customers like to do. Both can be morphed pretty efficiently. The higher-poly mesh may deform better over female chests, if it is a female item, where the lower-poly item may be much lighter on system resources.
Some artists prefer to just go for broke and have the pants be up in the 90k range. I call that pretty high poly, but if it's the only way to get the look you want and your system (and the prospective customer's system) can afford it, go for it.
I think a good rule of thumb is that your item should not be lower in polygon density than the figure to which it is conformed. Density is something you can only tell by looking at one mesh layered over the other to see how many polygons are in a given area and how large they appear. Genesis is not super dense in polygons at its base resolution; Victoria 4 is somewhat more so.
Wow, thanks for the detailed answer.
Concerning folds and wrinkles I usually do this:
Big folds that are visible at different angles and affect quite a part of the mesh (thinking of big folds on a skirt or the sleeves of a wide shirt) I do with the mesh. Smaller folds and wrinkles that are more for decoration I do with displacement. Think of a "schoolgirl type" of skirt. The big folds over the tighs are in the mesh, small wrinkles at the stomach area are displacement. Hope that makes sense :-)
Then I'd say you're fine with a "low to mid" poly count, i.e., one roughly as dense as your underlying figure rather than one two to four times as dense. Triangulating the chest area after everything else is finished is a technique I've been exploring lately for improving deformation in that area (I don't use it as a base modeling technique since it's impossible to efficiently select and manage flow of polys with triangles on).
Ok, thanks again. I will try that.
Yes I have also heard about triangulation. Some say it is important to "Triangulate non planar facets". Hexagon has a dedicated function for this (found under Tools - Utilities). The reason is that most renderers can´t handle non planar polygons. To be honest, I have never payed attention on that, and I never used that so far and I never had any problems due to non planar facets. I always try to have 4 sided polygons in the end. Do you know more about this?
For the most part DAZ and Poser have always done better with quad polygons. It's only recently that DS has started to handle triangulation and ngons (polys with five or more sides) better, and even then, one has to check carefully for "dark" faces on import into DS (render artifacts caused by too sharp an angle on the poly vs. those near it).
I use it, but very deliberately and in very specific areas; the thing some people do with Sculptris or other modelers where they end up with nothing but a mess of crazy triangles is not usually going to render well in Studio. If you're doing something simple enough to test out with a fully quad vs. a partly triangulated version, especially on a female chest item, try and see how you feel about it.
Great answer Sickle! Also I wanted to mention that its good practice to manually add additional polys in the area that need them like around the chest rather than just hit the subdividing button and create more across the whole mesh. I've recently been playing with zbrush and its remesher which is a fantastic tool so I've been thinking about poly use myself.
Oh for sure. This is very easy to do in Blender now since its subdivide function affects only selected polygons (this will cause edge n-gons or tris, but that's not really an issue any more).
Oh for sure. This is very easy to do in Blender now since its subdivide function affects only selected polygons (this will cause edge n-gons or tris, but that's not really an issue any more).i was actually referring to using tools in hexagon where you can add edges there are a number of them and it allows you to place the new edges exactly where they are needed lol...hex can't do that!
http://www.daz3d.com/new-releases/limelight-dress-for-genesis-2-female-s
If you look at the texture template of this new product, you can see that it is made of triangles only. So triangles seem to work as well :-)
Edit: A quick look at other products from this vendor showed me that all of them are made of triangles.