[Mono-dev] Problem with PNG transparancy on current Debian Unstable

Tue Jun 9 13:59:32 UTC 2015

Good job, now you should file the bug in http://bugzilla.xamarin.com/ 
and find a way to fix the bug in a way in which it doesn't make bug 
426305 or 324503 reappear.

On 09/06/15 13:09, Benjamin Schieder wrote:
> I have found the bad commit (and learned how to use git bisect in the
> process):
>
> [01:04:04][blindcoder at flora:~/Downloads/libgdiplus]$ git bisect bad
> 59ca17e56adb8555e9b4e0960b771f2849f6366f is the first bad commit
> commit 59ca17e56adb8555e9b4e0960b771f2849f6366f
> Author: Dick Porter <dick at acm.org>
> Date:   Thu Mar 31 16:02:19 2011 +0100
>
>      Don't premultiply PNG images on loading, no other format does this.
>
>      When drawing images, except when drawing onto a memory bitmap,
> premultiply
>      if needed.
>
>      Fixes bug 426305, without breaking bug 324503.
>
> :040000 040000 bc4a7075f87afdb5dc6e67c859cd82b06876d29e
> cf1cea632be730ad978409f224766097ba1382ea M    src
> [git:(59ca17e...)|BISECTING][A:0][D:0][M:1][?:5]
>
> If I check out 059ca56800ccca8249260fac5e9e8b45291b8237, the
> transparency is fine.
> When I update to 59ca17e56adb8555e9b4e0960b771f2849f6366f, the
> transparency is incorrect.
>
> Kind regards,
> Benjamin
>
> Am 2015-06-09 12:45, schrieb Alexander Köplinger:
>
>> There aren't that many commits for pngcodec.c in the last 4 years
>> (which is when 2.10 was tagged), so it's probably one of those:
>> https://github.com/mono/libgdiplus/commits/master/src/pngcodec.c .
>> Shouldn't be too hard to figure out which one broke your scenario.
>>
>> -- Alex
>>
>> > To: knocte at gmail.com
>> > Date: Tue, 9 Jun 2015 12:31:43 +0200
>> > From: benjamin at anderdonau.de
>> > CC: mono-devel-list at lists.ximian.com
>> > Subject: Re: [Mono-dev] Problem with PNG transparancy on current
>> Debian Unstable
>> >
>> > Alright, I compiled libgdiplus 2.10 and put it into /opt/libgdiplus2.10/
>> > I then did the following:
>> > LD_LIBRARY_PATH=/opt/libgdiplus2.10/lib/
>> > export LD_LIBRARY_PATH
>> > ./transparancy.exe
>> >
>> > And it works fine. So I guess there is a regression somewhere in
>> > libgdiplus between 2.10 and today.
>> >
>> >
>> > Am 2015-06-09 12:17, schrieb Benjamin Schieder:
>> > > I have this version on squeeze:
>> > > ii libgdiplus 2.10-3+b1
>> > > armel interface library for System.Drawing of Mono
>> > >
>> > > And this version on unstable:
>> > > ii libgdiplus
>> > > 3.12-0xamarin1+jpeg62.1 amd64 interface library
>> > > for System.Drawing of Mono
>> > >
>> > > I'll try to compile a 2.10 version of libgdiplus, but that's a lot of
>> > > difference and probably way above my head to bisect correctly.
>> > >
>> > > Am 2015-06-09 11:50, schrieb Andres G. Aragoneses:
>> > >> You could check what version of
>> > >> libgdiplus(https://github.com/mono/libgdiplus) did Debian Squeeze
>> > >> include, and try to run a custom new mono built from sources, with an
>> > >> older libgdiplus, to confirm that it is a libgdiplus regression.
>> If it
>> > >> is, then after that you could try to bisect the commit that
>> caused it.
>> > >>
>> > >> On 09/06/15 11:40, Benjamin Schieder wrote:
>> > >>> Hello Alex.
>> > >>>
>> > >>> I have followed those instructions and done a dist-upgrade, but
>> after
>> > >>> re-compiling with mcs the problem persists unchanged. I have the
>> > >>> following versions now:
>> > >>>
>> > >>> [11:38:29][blindcoder at flora:~/Downloads/PZ/MapMap]$ mcs --version
>> > >>> Mono C# compiler version 4.0.1.0
>> > >>> [11:38:34][blindcoder at flora:~/Downloads/PZ/MapMap]$ mono --version
>> > >>> Mono JIT compiler version 4.0.1 (tarball Thu May 28 09:08:28 UTC
>> > >>> 2015)
>> > >>> Copyright (C) 2002-2014 Novell, Inc, Xamarin Inc and Contributors.
>> > >>> www.mono-project.com
>> > >>> TLS: __thread
>> > >>> SIGSEGV: altstack
>> > >>> Notifications: epoll
>> > >>> Architecture: amd64
>> > >>> Disabled: none
>> > >>> Misc: softdebug
>> > >>> LLVM: supported, not enabled.
>> > >>> GC: sgen
>> > >>> [11:38:37][blindcoder at flora:~/Downloads/PZ/MapMap]$ cli --version
>> > >>> Mono JIT compiler version 4.0.1 (tarball Thu May 28 09:08:28 UTC
>> > >>> 2015)
>> > >>> Copyright (C) 2002-2014 Novell, Inc, Xamarin Inc and Contributors.
>> > >>> www.mono-project.com
>> > >>> TLS: __thread
>> > >>> SIGSEGV: altstack
>> > >>> Notifications: epoll
>> > >>> Architecture: amd64
>> > >>> Disabled: none
>> > >>> Misc: softdebug
>> > >>> LLVM: supported, not enabled.
>> > >>> GC: sgen
>> > >>>
>> > >>> Kind regards,
>> > >>> Benjamin
>> > >>>
>> > >>> Am 2015-06-09 11:07, schrieb Alexander Köplinger:
>> > >>>
>> > >>>> It works fine here with latest Mono 4.0.1.44 on Ubuntu. Can you try
>> > >>>> upgrading to latest Mono from Xamarin by following
>> > >>>>
>> http://www.mono-project.com/docs/getting-started/install/linux/#debian-ubuntu-and-derivatives
>>
>> > >>>> ?
>> > >>>>
>> > >>>> I suspect this has something to do with libgdiplus (the native
>> > >>>> library
>> > >>>> most of the System.Drawing code calls into).
>> > >>>>
>> > >>>> -- Alex
>> > >>>>
>> > >>>> > To: mono-devel-list at lists.ximian.com
>> > >>>> > Date: Tue, 9 Jun 2015 10:15:02 +0200
>> > >>>> > From: benjamin at anderdonau.de
>> > >>>> > Subject: [Mono-dev] Problem with PNG transparancy on current
>> Debian
>> > >>>> Unstable
>> > >>>> >
>> > >>>> > Hello.
>> > >>>> >
>> > >>>> > I have a problem with PNG transparancy in mono on current Debian
>> > >>>> > Unstable.
>> > >>>> > I created a small example (4 kB download) with minimal code
>> and two
>> > >>>> > example images:
>> > >>>> > https://oc.anderdonau.de/index.php/s/VwTAlcjETG6j3XP
>> > >>>> >
>> > >>>> > Running this example on a current Debian Unstable results in
>> this - bad
>> > >>>> > - image:
>> > >>>> > https://oc.anderdonau.de/index.php/s/AtVtba0tpSk4bn8
>> > >>>> >
>> > >>>> > Running the same code on an old Debian Squeeze (on armel)
>> results in
>> > >>>> > this - correct - image:
>> > >>>> > https://oc.anderdonau.de/index.php/s/eqhmXh9qpBbg0WW
>> > >>>> >
>> > >>>> > Can someone help me with this issue?
>> > >>>> >
>> > >>>> >
>> > >>>> > Kind regards,
>> > >>>> > Benjamin
>> > >>>> > --
>> > >>>> > Jabber: blindcoder at jabber.ccc.de
>> > >>>> > Twitter: https://twitter.com/blind_coder
>> > >>>> > Web: http://www.benjamin-schieder.de/
>> > >>>> > _______________________________________________
>> > >>>> > Mono-devel-list mailing list
>> > >>>> > Mono-devel-list at lists.ximian.com
>> > >>>> > http://lists.ximian.com/mailman/listinfo/mono-devel-list
>> > >>>
>> > >>> Jabber: blindcoder at jabber.ccc.de <mailto:blindcoder at jabber.ccc.de>
>> > >>> Twitter: https://twitter.com/blind_coder
>> > >>> Web: http://www.benjamin-schieder.de/
>> > >>>
>> > >>>
>> > >>> _______________________________________________
>> > >>> Mono-devel-list mailing list
>> > >>> Mono-devel-list at lists.ximian.com
>> > >>> http://lists.ximian.com/mailman/listinfo/mono-devel-list
>> > >>>
>> > >>
>> > >>
>> > >> _______________________________________________
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>> > >> Mono-devel-list at lists.ximian.com
>> > >> http://lists.ximian.com/mailman/listinfo/mono-devel-list
>> >
>> > --
>> > Jabber: blindcoder at jabber.ccc.de
>> > Twitter: https://twitter.com/blind_coder
>> > Web: http://www.benjamin-schieder.de/
>> > _______________________________________________
>> > Mono-devel-list mailing list
>> > Mono-devel-list at lists.ximian.com
>> > http://lists.ximian.com/mailman/listinfo/mono-devel-list
>
> Jabber: blindcoder at jabber.ccc.de <mailto:blindcoder at jabber.ccc.de>
> Twitter: https://twitter.com/blind_coder
> Web: http://www.benjamin-schieder.de/
>
>
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