A new visual bug in 2.41 version about pictures with alpha

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jeeg
Posts: 62
Joined: Wed Mar 18, 2009 8:11 pm

A new visual bug in 2.41 version about pictures with alpha

Post by jeeg »

Versione 2.41 solved an old issue I had with TGAs with alpha!
I'm very happy but I found a new bug.
This is again a bug related to pictures with alpha but it happens with all formats with alpha. Not only TGA.
This bug happen only when the picture is bigger then the screen. Xnview show the picture scaled so that it fits the screen and this cause the bug!
If I zoom in or zoom out the picture, I see it perfectly.

I want to add another thing. This bug is visible only when Xnview's window is big as the screen (maximized)! If the Xnview's window is a floating window the bug disappears.

I show you the bug:

This is what I see when I double click a picture that has alpha and is scaled to fit the xnview canvas. Do you see all those white dots?
Image

If now I zoom in or zoom out the the dots disappear. This image is at 100% here
Image

If I open a picture smaller then the previous there is no bugs. In this picture I opened a scaled version of the previous image. See? No dots because it opens at 100% zoom
Image

I add that the dots appear also if I click "M" to see the alpha of the picture. In this image the alpha is white. Do you see the black dots?
Image

I attach a copy of the picture used in these example.
You can download it here:
https://www.mediafire.com/file/pw2gov3u ... g_dots.rar
Last edited by jeeg on Sun Oct 15, 2017 3:58 pm, edited 1 time in total.
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Re: A new visual bug in 2.41 version about pictures with alpha

Post by xnview »

right :bugconfirmed:
Pierre.
jeeg
Posts: 62
Joined: Wed Mar 18, 2009 8:11 pm

Re: A new visual bug in 2.41 version about pictures with alpha

Post by jeeg »

Mr Pierre!
Another bug!!!!
I hope you read this or I will have to open a new thread.

This new bug is related to the one I wrote in the first message!

Open the same picture of the first message. In my monitor the picture is initially shown at zoom 88%

Now press M to see the mask.
Nothing happen! You don't see the mask!
If now you zoom out you still don't see the mask!
Now zoom in till you reach 100%! Tadaaaah! Now you see the mask!
If you zoom out again the mask disappear again and you'll see the picture as normal.

In other words:
The "show mask" feature only works when the picture is at 100% or more. If less you cannot see the alpha channel/mask

This bug is very annoying...not as the bug in the first post (the little white dots) that is not important.
Bye!
jeeg
Posts: 62
Joined: Wed Mar 18, 2009 8:11 pm

Re: A new visual bug in 2.41 version about pictures with alpha

Post by jeeg »

I found another crazy behaviour!
This time is really weird!

Download this png file:
https://www.mediafire.com/file/4owj5h0w ... Main_l.png

Look what happens inside Xnview.

When I open the png is shown at 88% to fit the window and it's a chaos of colours!
If I zoom in to 100% or more it became white and grey (it's real colour)
If I zoom out to less then 88% it became totally red (What???).

Really...Xnview it's a chaos right now!

Image
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XnTriq
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Re: A new visual bug in 2.41 version about pictures with alpha

Post by XnTriq »

jeeg wrote:I found another crazy behaviour!
This time is really weird!
Hi jeeg, there's a workaround for this bug: Open logo.png and activate ViewUse alpha channel.
jeeg
Posts: 62
Joined: Wed Mar 18, 2009 8:11 pm

Re: A new visual bug in 2.41 version about pictures with alpha

Post by jeeg »

I can't! "Use alpha channel" is greyed out! Because the image has not alpha at all.

Edit:
I read that thread now! I changed "use alpha" to 1 in the ini file. Now that bug is fixed. Thank you.
Please don't forget about the other two bugs in this thread. Bye
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XnTriq
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Re: A new visual bug in 2.41 version about pictures with alpha

Post by XnTriq »

jeeg wrote:I can't! "Use alpha channel" is greyed out! Because the image has not alpha at all.
That's why I asked you to open logo.png ;-)

In order to turn ViewUse alpha channel on and off, Ignore alpha channel (ToolsOptions...GeneralOperations) has to be disabled, and you have to open a 32-bit image in view mode. If you're dealing with a PNG file, you also have to deactivate → Compose image with alpha (32bits) in ToolsOptions...Read/WriteReadPNG.
jeeg
Posts: 62
Joined: Wed Mar 18, 2009 8:11 pm

Re: A new visual bug in 2.41 version about pictures with alpha

Post by jeeg »

Thank you for solving these bugs in the new version! :D
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