1.91.6: Checkerboard background

[oops66]

* Option to use 'checkerboard' for transparency - http://newsgroup.xnview.com/viewtopic.php?t=13645

I'm using linux+wine so I'm not sure the following problems occur in native OS:
1. Enable checkerboard option
2. Highlight png with 32 bits & alpha channel (crash).
Sample png found here

I can't confirm, i have no crash. Someone have the same problem?

Yes, I confirm this crash the first time (with this png sample :here)
thumbnail : without alfa channel :
with alfa channel :
But after uncheked and checked Options\read_write\read\PNG :
compose image with transparency and
compose image with alpha (32bits)
I do not have this crash again ... strange...

But I can not see the checkerboard background (for gif or png ...)
with the option : use 'checkerboard' for transparency

[Clo]

Hello !

• Here, simply ticking the box >> OK for that option (“Use checkerboard for transparency”) causes that XnView crashes immediately, while a transparent image is displayed in “View” (main window).
- It's only an *.ico file, 24×24 (24 BPP, but it's processed as 32 BPP in XnView to solve the transparent display issue for *.ico).

KR
Claude
Clo

Note >> Pierre : for «checkerboard» I'ld suggest you ”fond pigaillé” in French…

[xnview]

Ok, the problem is when you are not in 32bits display!

[oops66]

Hello,

Ok, for “Use checkerboard for transparency” & 16bits display.

Yes, it's a good idea (if checkerboard for transparency works in all cases of transparency pictures (for gif ...5...8bits... and png 32, 24 ... )!
And for 32 and 16bits display - it is not very useful for 256 or 16colors screen display (usualy I only set the Windows 16bits colors display for efficiency).
About the checkerboard ”fond pigaillé” in French, is it possible to have a picture of it, Clo ?

[Clo]

—> oops66

Hello !

• Unfortunately, no because the soft in which I see it locks the PrintScreen key !

- It's not different from the chequered pattern, except that the white¦light-grey cells are shown shifted by ½ pixel (supposing you display a pic with the regular grid).
- That produces a different visual effect. Something like below :



Where the real layout of the pixels is shown as a pastel blue coloured grid.
A part at the right¦top corner is drawn without that grid (it's better to blow up the picture…).

• Another kind of visible transparency (as white diagonal micro-dots) :



KR
Claude
Clo

[oops66]

Hello Clo,
Thank you for yours samples.
But, for me (only for me), I prefert by default the classic chequered pattern even if the others options are interesting too...
Have a nice evening.
Regards,
Oops66.

[ouistiti]

Clo

My prefered : Your other kind of visible transparency (as white diagonal micro-dots)

Friendly

Paul

[Clo]

—> Pierre

Hello !

Ok, the problem is when you are not in 32bits display!

• I can't set 32 BPP usually because I've an on-board video (Intel m-b) with a shared memory… and I'm not the only !
In such cases, I think that the OTHER SOLUTION as optional could do the trick much better.
- The "medium" colour exists already, this is only a small classic box¦option section easy to add, IMHO…

- I wonder that you didn't answer there…

KR
Claude
Clo

[oops66]

I notice than if in the configuration menu :
Options\ read/write \read\PNG \ compose image with alpha(32bits) checked
Then I can not see the checkerboard for transparency.(even if options\view\use checkerboard pattern as background is checked)


And if "compose image with alpha(32bits)" is unchecked
then I can see the checkerboard for transparency.


(same thing for both Windows 16bits colors display or 32bits screen display ).
Why if use checkerboard pattern as background is checked you do not uncheck automaticaly "compose image with alpha(32bits)" Pierre ?

Anyway, your 1/4 of pixel checkerboard in full zoom is very useful ( for transparency).... congratulations....

[Clo]

Hello !

• I tested the current chequered pattern with small images (icons 24²), and I noticed that it's not satisfactory,
since the cells (marked for the “Grey” with purple dots) remain with the same size,
no matter which scale you display the image (please, blow up it) :



• It's getting usable¦useful when such an image is blown up by 500…600% at least :



- It's an issue similar to the mesh of the grid when set for a high zoom-in ratio (no auto-adjustment of the mesh).

• Hence, I say still that a complementary feature to the chequered pattern like quoted above
(choose among 3 BG-colours at will on the spot) is needed too…

KR
Claude
Clo

[oops66]

It will be nice also to have a checkerboard background (for gif and png 8bits of colors ...)
Regards,
Oops66

[ouistiti]

Hello !

Like Clo said above, the current chequered pattern is not useful with small images.

- I guess that an option to set the cells size could help, something like the mesh for the grid.

- At the very outside, only an INI entry could do the trick temporarily…

What do you think ?

Friendly

Paul

[Clo]

—> ouistiti

Hello Paul !

• Indeed that workaround should be better than the current situation, so I support it !

Friendly,
Claude
Clo

[Clo]

oops66

{ Just over six months later… }

Hello !

• During that loooong time, the basic pattern was not improved, hence the above-mentioned lacunaæ remain…

• Meanwhile, we (*) discovered the GFIE freeware programme, in which that feature is more elaborate :



• It's similar to the pattern I couldn't copy in another icon editor formerly, but with an advantage :
The colours of the mini-cells can be chosen at will by the user, according to the kind of hues s¦he's in the habit
to work with (rather light or dark ones) …

- Let's notice that the pixels having a partial opacity are shown alright with that pattern on the image above
(a small part of a 32-BPP PNG, scale 20:1).

- As a first step, even only a colour choice could help I guess, and to save the Pierre's time, as extra INI entries like i.e. :

TranspPattern_1= Colour value
TranspPattern_ 2= Colour value

- Then, a change of the current pattern layout¦cell-size is indeed desirable (a lot !).
• To compare, the scale 1:1 full image used here, in GFIE (left) and in XnView (right) :



“Quod erat demonstrandum”

(*) We = XnTriq prior (thanks again), then Paul and I who started to help at this soft, a good choice, really…

KR
Claude
Clo

[oops66]

Hello Clo and all,
I have discovered GFIE (Greenfish Icon Editor Pro v1.51 http://greenfish.extra.hu/downloads.php ) and this is really a very nice tool too - thanks Clo.
+1, I agree with you, it would be better to have the possibility to change the colours of the mini-cells of the checkerboard background.
And it would be also better to have a transparency pattern for the 8 bits deep colors files (png_8bits , gif,....).
Have a nice day,
Oops66.