I'm having an issue which I'm hoping someone can give me some insight into.

I created a mesh (original non 'mesh2' object) macro to create a spherical
segment based on parameters specified (ie theta angle, sigma angle, radius of
inner shell, radius of outer shell).

In a nutshell its created by first cunstruction of a tiny closed mesh object
(thereby enabling use of the 'inside_vector' modifier), comprised of 6 sides and
12 'triangle' objects, and  with UV parameters supplied by the calling macro.
The calling macro creates a union of the smaller mesh objects based on a set
number of divisions in the theta and sigma (angles), and radius directions.

My problem is that no matter how I apply the use of the 'uv_mapping' and the
'texture' statements, POV always applies the 'texture' first then applies the
'inside_vector'. The problem with this is when working with transparent
'image_map' objects (such as the icon image in the upper right quadrant of the
attached image) yields unintended results  such as those in the corners of the
mapped image (upper left quadrant).

I've tried changing the order such that the texture is applied both to the
'mesh' objects individually, and to the 'union' of the individual meshes, but
with the same result. I would think that since the 'inside_vector' is applied to
the individual mesh objects, if the texture is applied to the 'union' object
this would do the trick, but this does not appear to be the case

Since the documentation says it was designed for CSG, I've tried encasing the
mesh in other "normal" objects (such as a 'sphere' or 'box') hoping this would
resolve the issue. The 'inside_vector' does appear to be working correctly as
indicated by the two bottom pictures (left with the 'inside_vector' parameter
added to an intersected object, right without the 'inside_vector'  parameter
added).

It seems to be an issue in determining what is the surface that needs to have
the 'inside_vector'. Ideally, POV would calculate the surface first (thereby
making it solid), then apply the texture with the transparency. But as
indicated, it seems to be applying the texture incororating the transparency
first, thereby making parts of the mesh faces transparent, and then applying the
'inside_vector' (and making the result solid) secondly.

Anybody have any recommendations for a fix?

I know this is in unitended consequence (at least for me), but is this a bug in
general? Or just some limitation?

Is it something that can be corrected in future versions of POVray so as not to
require a fix? That is can POV be programmed so the user can change the order in
which the 'inside_vector' and transparent 'image_map' are applied?

-Jeff

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