POV-Ray : Newsgroups : povray.binaries.images : using 'transmit all' with PNG alpha-channel image_maps-- a flaw? : Re: using 'transmit all' with PNG alpha-channel image_maps-- a flaw? Server Time
15 May 2024 07:09:02 EDT (-0400)
  Re: using 'transmit all' with PNG alpha-channel image_maps-- a flaw?  
From: clipka
Date: 11 Jan 2016 02:09:22
Message: <56935522$1@news.povray.org>
Am 11.01.2016 um 04:09 schrieb Kenneth:

> Yes indeed, that does eliminate the 'hard-edged matte' quirkiness of my
> fading-out TIFF image. Thanks for pointing this out. I'm embarrassed to admit
> that I *did* read about the new 'premultiplied' keyword-- then promptly forgot
> about it.  :-(  I just gave the docs there a good re-reading!  I actually wasn't
> sure *why* it was necessary, until now. What a big difference it makes!
> 
> So all that remains is to find a fix for the previously-mentioned 'transmit all'
> transparency problem, with its erroneous complementary colors etc.  ;-)

The newest `master` branch should fix the interaction between image
alpha channel and "transmit all" (and "filter all" likewise), AND also
implement auto-detection of TIFF alpha mode.

As I'm not really sure whether some existing scenes might be relying on
the old quirk, the new "transmit/filter all" behaviour requires
"#version 3.71".

I'll publish one of those famous(?) semi-official builds once I've
gotten me a fresh batch of round tuits (presumably next weekend).


Post a reply to this message

Copyright 2003-2023 Persistence of Vision Raytracer Pty. Ltd.