Retsam,
    Christopher James Huff is on a TAG team and I'm sure it will get
noted and checked...

Emory

Retsam wrote:
> 
> >Christopher James Huff wrote:
> >>No, the second glass refraction is ignored. POV maintains a list with
> >>the objects it is currently "inside", which lets it figure out when
> >>refraction should be done.
> >>
> >I know that's probably what's intended, but I'm just looking at the code.
> 
> I ran a test to confirm my suspicion.  Rays were refracted twice at an ior
> of 1.57:1.33, once on entering the water, and once on leaving the glass
> (into the water).  I did the test with POV-Ray 3.5 for Windows (Version
> 3.5.icl.win32)
> 
> If it really is supposed to work the way you described, where it only
> refracts when leaving a surface if it's the last surface entered, then we
> should make the following code change:
> 
>       /* The ray is leaving the current object. */
>       Ray_Exit(&NRay, nr);
>             if (NRay.Index == -1)
>       {
>         /* The ray is leaving into the atmosphere. */
>            .......
>       }
>       else if (NRay.Index+1 == nr)   <------ this line was changed.
>       {
> 
> I could be off by one.  But as I read it, NRay.Index should equal nr if the
> ray is leaving the last object entered.  After the call to Ray_Exit,
> NRay.Index will be reduced by one: hence the "+1" in the if statement.
> 
> I apologize if this post appears twice.  I posted a similar response last
> night, and it hasn't shown up yet nearly a day later.
> 
> By the way, do the developer's read messages in here?  Who would I talk to
> about making this code change, if it is the way it should be handled (the
> documentation doesn't really describe the way it's supposed to work in
> tricky scenarios like this)?

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