Mesh size best practices

[Dazz Anvil]

I've been experimenting with a few different models of various complexities. Are there guidelines established yet as to how many verticies are reasonable for a model? Obviously I can subdivide my stuff to increase smoothness and wind up with a ridiculous number of them, but how many are about right for the environment? 100, 1000, 10000? Have absolutely no feel for this.

[Drongle McMahon]

That depends entirely on what you are making and how big it is. The prim cost, charged against the parcel allowance, will depend on both and is likely to be the determining factor, unless its an attachment, in which case the considerations are different. It's all a matter of compromise between detail and resource use. If you can give more details, someone might be abl to give a better answer.

[Dazz Anvil]

Ok, just for giggles, let's say I want to make a "boomerang style" coffee table something like this: http://www.flickr.com/photos/39201495@N04/4712725970/ I can extrude a spline of the requisite shape and get something that's not terribly complicated. But let's say I want to radius the edge of the table so that its rounded instead of square. Depending on how accurate that radius is, I can get a whole lot more verticies once I do that, but what's a lot? How many is too many?

[Drongle McMahon]

Costs aren't settled yet, and it depends a lot on on compressibility, type of edges, UV map etc. The best guestimate so far is about 250 vertices in the high-LOD (level of detail) mesh per prim. Sharp edges cost more. That depends on supplying good low-LOD meshes and a real simple physics shape mesh.

I guess you could get that looking smooth enough with 48 edge segments. Then if you use four loops for a bevelled edge and keep all the edges smooth, that would be 192 vertices. Unfortunately, those legs are expensive, say 36 verts each. That's 300 vertices total. Hmm. Might just squeeze it into one prim, but probably 2, at normal quality. If you are prepared for it to cost four or prims, you could double the vertices and make it extra smooth.That all assumes a very simple physics shape. A curved outline like this

If you look around the mesh sims, you will probably see something similar with 6000 vertices and costing 50 prims!

[DanielRavenNest Noe]

One guideline is if it's less than a pixel off on a large monitor, you don't need that detail.  So assume the table is 1/3 the screen height at normal view distance.  On a 1920x1200 monitor that will be 400 pixels tall.  On a corner, you can do a square edge, a chamfer, or a circular arc.  The more sides in the circular arc, the closer it gets to a perfect circle.  If the deviation from perfect at the midpoint of a side is less than a pixel, people viewing it will not see the difference, especially if you use smoothing groups properly.

Same general rule applies to texture sizes.  If the texture pixels as displayed on the object are under 1 pixel on the monitor, the texture is detailed enough.  The only question is what you consider an appropriate viewing distance, which will vary somewhat by type of object.  At the closest, there is a camera clip distance of around 0.5m.  Anything closer isn't rendered, so that sets a minimum feature size you can see of around 0.5mm.

[Dazz Anvil]

That's great info. Thanks!