I'm trying to create a reflective concave surface and I'm getting artifacts and the polygon edges of the surface are visible.  Click on the image for a larger size to see the lines in the wall just above the disk as well as the odd artifacts.

I'm using BB's Glossy material for the reflective surface, and his Environment sphere to give it something to reflect.

I'll post the render settings, material settings, and model wireframe next.

Thanks in advance.

 -s

Render Settings

Material settings for the wall.

The disk is similar - the IOR is much lower and the diffuse color is a different.

Wireframe of the prop - created in Wings 1.4.1.

I've fixed the artifact problem by getting rid of the multiple thin polygons at the top and bottom of the wall.

I'm still seeing the horizontal edges in the wall however.

Oh yea - I forgot to mention, this is with Poser Pro 2010 (8.0.3.11916) running on Win 7 64 bit.

it ameliorates the ffrender issue of intersecting normal surfaces if the line of intersection is welded and/or slightly curved/bevelled, but they addressed this in later version(s) IIRC.

I have just had a similar problem on a dynamic cloth item,with the edges of the polygons showing in places when rendered.

I solved it by increasing shadow min bias on my light from .1 to .5

There is also a bias on the Reflect node in the shader that may be a factor. I often run into reflection trouble with concave polygons in Poser. This happens big time when doing ocean waves.

I think I've figured it out.  From my testing, it looks like it is the size of the polygons that is causing the problem.  My curved wall is 32 poser feet across and 10 feet tall.  The wall is broken up into 320 faces, each approx. 1.57 poser feet wide by 2 feet tall.  I first tried triangulating the faces to see if that would help, but it didn't (but it did look cool).  I then went back and smoothed the wall which subdivided each face into 4 faces, but I still had the problem. So I tried subdividing again, and it appears to have worked.

I'm attaching the triangulated original wall to this post and I'll attach the 2x smoothed one to the next post.

Here's the 2x smoothed version.  It does have an interesting "artifact" on the right side that I can't figure out.  I'm not sure if it's part of the floor that doesn't show up in the other version because of the face size or if it's an artifact once the face size drops.

Not face size, but curvature. As you make the faces smaller, they are approaching being more like flat polygons.

All polygons in a mesh may not be flat, but all edges are straight lines, you cannot make curved polygons.

Now we're likely to speak past each other as you and I make differing assumptions and use words we both know but inadvertently do not agree on the meaning.

There is no doubt that the set of points directly between two vertices is a straight line.

Where we disagree is in our understanding of what Poser creates for the interior points of a polygon.

Poser will not render the edges of a polygon as straight, but rather as a curve, if smoothing is on and the adjacent polygons are not coplanar. There is also no doubt that the surface normal of a polygon will differ from a truly flat one if the adjacent polygons are not coplanar and below the crease angle, regardless of whether smoothing is on or off. The notion of a concave polygon is quite literally real in Poser, even if you don't directly model it.

I can show you curved polygons quite easily.

I made a prop with 3 planar quads, welded. Behind this prop, I am floating a cylinder as a visual aid to understand the geometry.

Rendered with smoothing off on the 3-panel prop.

And now with smoothing on. Voila - edges that are not straight.

We are talking at cross purposes here. I was referring to the mesh, in this case entirely made from flat polygons, and you are talking about the rendered appearance, which makes the polygons appear curved.

What Happened?  Renderosity suddenly changed and the forum is now narrow instead of full screen width, with garish colours.

Quote - And now with smoothing on. Voila - edges that are not straight.

OK, I'm with you 100%.  Now would you change the material to be reflective?  Doesn't need to be fancy for this.  I'm curious if the reflective surface follows the smoothed surface or the "actual" surface.

Thanks.