Re: png app icons not working?

[Fred Kiefer]

I finally found and fixed the issue. It was a completely nonsensical bit
operation in a helper function.

The code should now work correctly for 16 bit image data, but for more
bits it is still completely wrong and will result in corrupt data. We
need some backstop code here. Any taker?

Fred

On 20.10.2013 21:55, Fred Kiefer wrote:
> I am currently investigating this issue and things look bad :-(
> 
> The display problem is caused by the _premultiply on NSBitmapImage.
> (This can be easily confirmed by commenting out the _premultiply call in
> the draw method)
> 
> This method in itself seems to be correct, most likely the error is in
> the setPixel: or getPixel method (or rather the functions used there)
> that isn't able to handle the 16 bit format of the PNG image. I am still
> trying to figure out, which of these it is and how to fix it. Hope to
> report back soon with better results.
> 
> Fred
> 
> On 18.10.2013 09:58, Sebastian Reitenbach wrote:
>> Hi,
>>
>> I'm on OpenBSD amd64, latest gnustep core releases installed, compiled with 
>> clang, non-fragile-abi.
>>
>> I have the following png installed: 
>> png-1.6.6
>>
>> configure stage of -gui is checking and finding png:
>> checking for libpng-config... yes
>> checking png.h usability... yes
>> checking png.h presence... yes
>> checking for png.h... yes
>> checking for png_sig_cmp in -lpng... yes
>> ...
>>
>> and its also linked against it.
>>
>> I tried Camera from the gsimageapps:
>> http://home.gna.org/gsimageapps/
>>
>> and I found that the app icon is a png. When the application starts, then
>> in the app icon, and in the Info panel, I only see a white square, instead
>> of the camera icon. I used gimp to resave the Camera.png as Camera.tif
>> and tweaked the GNUMakefile to use the tif instead. With the tif I see the
>> expected Camera icon.
>>
>> Now I'm wondering what the actual problem is, something in my setup,
>> something more general problem in -gui? Since this Camera is a relatively
>> old app, I guess it must have worked at some point in time with the png
>> image too?