#34 Please include license for src/images/castlefpwritepng.pas

[Paul Gevers]

The new file src/images/castlefpwritepng.pas in 5.2.0 seems to be taken from fpc. The mention COPYING.FPC file is missing however. Please include the full license statement either in the header of the file, or as a seperate COPYING.FPC file somewhere in your source tree.

[Michalis Kamburelis]

The license of FPC RTL is "LGPL with static linking exception", exactly the same as CGE. The file COPYING.FPC merely contains the text of that exception, available also in our own COPYING.txt, since CGE uses the exact same wording. So I simply changed the header of the file, to say

    This file is adapted from the FPC RTL source code, as such
    the license and copyright information of FPC RTL applies here.
    That said, the license of FPC RTL happens to be *exactly*
    the same as used by the "Castle Game Engine": LGPL (version 2.1)
    with "static linking exception" (with exactly the same wording
    of the "static linking exception").
    See the file COPYING.txt, included in this distribution, for details about
    the copyright of "Castle Game Engine".
    See http://www.freepascal.org/faq.var#general-license about the copyright
    of FPC RTL.

Also, the problem was actually present in a couple of other files too. I fixed them all, see commit https://sourceforge.net/p/castle-engine/code/14585/ .

[Paul Gevers]

Thanks a lot for clarifying. (And yes, I know the fpc license, I just believe cge must also have correct license statements).

By the way, do you already have an idea of how to keep the file in sync with fpc? (Did you forward you changes, or doesn't that make sense)?

[Michalis Kamburelis]

By the way, do you already have an idea of how to keep the file in sync with fpc? (Did you forward you changes, or doesn't that make sense)?

These files do not really need to be actively kept in synch with FPC, they are (mostly) just interfaces to libraries. Of course it would be nice, but in practice it's not necessary, for the most part --- these files are internal to the engine.

As for submitting the changes: some of them are submitted, some of them could be (but are not, due to simple lack of time on my part):

• src/fonts/castlefreetype.pas : could be submitted to FPC, but in fact the need for some of mine modifications will disappear with new string handling in next FPC 3.x release.

• src/fonts/castleftfont.pas : depends on src/fonts/castlefreetype.pas.

• src/base/castlexmlcfginternal.pas : like above (string handling in FPC 3.x will fix this globally), and some parts are specific to CGE (use URLs and custom download/upload routines underneath). In theory, FPC XMLCfg could be changed to allow extending it in a way I want --- but this requires a little work to prepare a suitable patch to XmlCfg.

• src/images/castlefpwritepng.pas : when http://bugs.freepascal.org/view.php?id=28082 (my ticket with patch for FPC) will be fixed in stable FPC, we can drop it from CGE,

• src/fonts/castlefreetypeh.pas , src/base/android/castleandroidcwstring.pas : should be submitted, since our modifications are necessary for Android (delay loading of xxx.so files).

• castlegziointernal.pas : should be submitted, contains a fix.

• src/base/castlezstream.pas : depends on above.