Grid lines appearing with Alpha on TGAs

Older bugs which are supposed to be fixed in 0.84. *** Please try to reproduce your bug and confirm the bug fix. ***

Moderators: XnTriq, helmut, xnview, Dreamer

insyami
Posts: 1
Joined: Fri Dec 04, 2015 5:16 pm

Grid lines appearing with Alpha on TGAs

Post by insyami »

I've used XnView for quite some time, and decided to try out XnViewMP because its UI is a little bit more polished and straightforward, however, I'm having what I believe is a bug when previewing TGAs with the alpha channel enabled. Here is the same file open on both XnView and XnViewMP with the Alpha channel disabled:

Image

Everything looks fine, but here's what happens when I enable the Alpha channel:

Image

Lots of grid lines appear over the image. They disappear if the zoom is on 100%, but appear again as soon as I zoom in or out, which makes me believe it's an issue with how the zoom function works.
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xnview
Author of XnView
Posts: 42479
Joined: Mon Oct 13, 2003 7:31 am
Location: France

Re: Grid lines appearing with Alpha on TGAs

Post by xnview »

yes a known issue
Pierre.
jumo
Posts: 1
Joined: Wed Jan 13, 2016 1:57 pm

Re: Grid lines appearing with Alpha on TGAs

Post by jumo »

It seems, I got the same issue on PNG.
It becomes very inacurate on few pixel wide images:
(eg: Image)

Is there any plan to fix it ?
Timmyfox
Posts: 1
Joined: Fri May 20, 2016 5:36 pm

Re: Grid lines appearing with Alpha on TGAs

Post by Timmyfox »

Still having this issue on 64-bit MP-version with PNG files, driving me nuts..
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helmut
Moderator
Posts: 8702
Joined: Sun Oct 12, 2003 6:47 pm
Location: Frankfurt, Germany

Re: Grid lines appearing with Alpha on TGAs

Post by helmut »

This problem is supposed to be fixed in XnView MP 0.84. Could you (insyami / jumo, / Timmyfox) please try and confirm the bug fix?

Related bug report:
- 0.68: Discontinuities when downscaling large images