devil: png support

[pashkoff]

Now, it uses pkg-config to find system png library.

[adamv]

What is the source of this patch? Can it be sent upstream?

[pashkoff]

I am the author of this patch. I have used m4 code from the same file (search for exr library) and have changed it for png.
Problem is that the project seems to be dead - last commit to the repo was in 2010, last closed bug was in 2010. So, I'm not sure that patch can be sent to the devil project upstream.

[jacknagel]

To use autoreconf this needs deps on autotools for Xcode 4.3+, e.g.

if MacOS.xcode_version.to_f >= 4.3
  depends_on "automake" => :build
  depends_on "libtool" => :build
end

[pashkoff]

@jacknagel, you are right. I checked it on clean mac os installation.
Also, I have found that library fails to compile using clang++.

[pashkoff]

Do I need something more to do with this request so it will be approved? Or there is some approval procedure which I don't know?

[jacknagel]

Nope, someone just has to find time to review it.

[pashkoff]

Okay, as I thought. Sorry for impatient bumping, thanks anyway.

[mistydemeo]

It looks like this is unnecessary if ENV.x11 is added to the formula - I'll fix this when I push a separate clang-related fix.

[PIlin]

@mistydemeo I did not known about ENV.x11. Unfortunately, I cannot test it now, but, if it will help to link against system libpng - it will be great. Much better than my heavy patching solution.

[pashkoff]

Argh, I did it again - made a comment from different account. @PIlin is me, sorry for confusion.

[mistydemeo]

Fixed in 87afdd0 - please let me know if this doesn't work for you!

[pashkoff]

@mistydemeo It worked, thanks.