Josh English wrote:
> 
> I had the same issue. Reverse the alpha channel and it will work just
> fine.
> 
> Steve Martin wrote:
> 
> > I'd like to do some compositing with images from POV-Ray using the
> > alpha channel in the TGA file. Unfortunately (and I can't believe
> > I'm the first to notice this, so I assume it's something I'm either
> > not understanding or doing wrong), it seems that the alpha channel
> > in the rendered image file is "reversed" from what it should be
> > (i.e. 0 instead of 255 and vice versa). I rendered a simple test
> > sphere, no specified background, one light, very simple. When I
> > call the image up, I find that there is a hole in the middle of the
> > image right where the sphere ought to be... but I can see the black
> > background with no problem.
> >
> > I thought perhaps it was something about TGAs, so I converted the
> > file to a GIF. Same thing... a black background with a hole in the
> > image where the sphere should be, exactly backwards from what I
> > expected.
> >
> > (BTW, I'm using ImageMagick and POV3.1g on a RH6 Linux system do
> > do all this.)
> >
> > Can someone tell me what I'm doing wrong?
> 
> --
> 
> Josh English
> eng### [at] spiritonecom
> ICQ: 1946299
> "Stress is when you wake up screaming and realize you haven't fallen
> asleep yet."

I've used the alpha channel with PNG output and it worked fine.
The PNG file format allows for the alpha channel to represent
either transparency or opacity.

Cheers, PoD.

Post a reply to this message