Hello,

Windows 7-64bit, POV-Ray 3.7 64bit RC5

I have been having some issues with the new Subsurface Light Transport. 
If the mesh is made up of several sub-meshes the seams between them are 
darkened.

Using a test model of a head about 7x11x9 inches, made up of several 
sub-meshes (either union or merge), 25mm per unit, translucent color of 
0.8, and ior of 1 (there was not much change with other values). I get 
the following:

http://imgur.com/5mw16

The skin does not have any image maps, bump, specular, ambient or 
reflection. There is one spherical area light and no radiosity. The dark 
edge is alleviated somewhat as the translucent color is decreased but it 
is always visible.

If I merge the mesh outside of POV-Ray into a single mesh with a single 
material for the complete head skin then the dark seams disappear. But I 
cannot merge the mesh outside POV-Ray since that would destroy the 
separate UV mapping that each mesh uses. Does POV-Ray 3.7 work with a 
union or merged mesh2 group and SSLT? The test model is open at the 
bottom but I also tested this with a closed sphere with two materials 
and it gave me the same dark edge between the materials.

Also the edges of the polygons are slightly visible on the forehead. 
That was easily fixed by subdividing the mesh before rendering.

FlyerX

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