[Bf-committers] scons issues with new ffmpeg package

[Ken Hughes]

I've hacked together scons support which for now will let me compile the 
ffmpeg libraries in linux, without having to run a separate scons or 
make session to build the libraries.  (Wish Nathan was around to tell me 
how to do this better). However, there are some issues which I think 
have been swept under the rug, so to speak, up until now that should be 
addressed.

(1) When the ffmpeg package runs ./configure (which is run from make 
only at this point), it generates a config.h file based upon the options 
specified and the platform.  I don't know if it will optionally include 
or exclude certain codecs based upon what other packages are installed 
but I suspect it does.  The end result, though, would be a different set 
of options potentially compiled for anyone using the "built in" ffmpeg, 
which could cause issues later should a bug come up.  I propose we 
decide on a "standard set" of options, and hence a standard config.h 
file, which will be the default unless the ./configure script is run.  
This means that if a user doesn't have some packages installed they will 
get an error when compiling, but this isn't any different from other 
requirements (some libraries are just "required" for a standard build).
(2) The include files for ffmpeg are kept in many separate directories, 
and when compiling the libraries this is fine.  When trying to compile 
any files outside of the extern/ffmpeg tree, they are all assumed to be 
in a single ffmpeg/ directory (hence the errors with "#include 
<ffmpeg.swscale.h>".  Since we're putting this code in our tree anyway, 
I think we should go ahead and install the necessary includes in a 
single directory.  If for no other reason than I can't figure our how to 
get scons to install them into a single directory in the middle of the 
installation process.

Thoughts?  Comments?  Better ideas?

Ken