Hello,

POV-Ray 3.6.1c.icl8.win32 running in WinXP SP2.

This scene has 4 mesh2 objects (box, ball, cylinder and bowl) and two 
parallel lights. All meshes intersect but do not have coincident 
surfaces. Y is up, X is to the right and Z is towards the camera aligned 
with the box. The meshes are separate and all have their own material 
and are hollow. All are placed inside an union statement. The only open 
mesh is the one on the left.

The rendered image is shown below:

http://mysite.verizon.net/sfg0000/images/testscene_render.png

here is the PoseRay mesh and axis orientation preview before rendering:

http://mysite.verizon.net/sfg0000/images/testscene.jpg

Link to scene POV-Ray code:

http://mysite.verizon.net/sfg0000/files/testscene.zip

The problem: There is a significant shadow gap between the left mesh and 
the box. I asked this question a while back and I was told to use 
inside_vector in the mesh2 statements. That helped somewhat with other 
cases but not with this. If I understand the inside_vector statement 
correctly then vectors Z and X should work since a ray should intersect 
the bowl mesh twice in those directions.

If I place split_union off at the end of the union then the gap 
disappears but I lose control on the shadow flag for all objects in the 
union. In other words no_shadow does not disable the shadow for any 
object.

I could use a texture list on the mesh2 statement but that does not 
allow me to use an interior in any of the meshes.

I also disabled the union and listed the objects separately but that did 
not have an effect on the gap.

The gap shows with all other light types and can be somewhat covered 
using large area_lights.

This gap only shows only if the meshes intersect.

Any insight will be appreciated. I know that open meshes in POV-Ray may 
be problematic but I wanted to know if there was a way around this 
particular issue. If you see anything wrong with the way I setup the 
meshes please feel free to let me know.

regards,

FlyerX

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