______   ___    ___
    /\  _  \ /\_ \  /\_ \
    \ \ \L\ \\//\ \ \//\ \      __     __   _ __   ___ 
     \ \  __ \ \ \ \  \ \ \   /'__`\ /'_ `\/\`'__\/ __`\
      \ \ \/\ \ \_\ \_ \_\ \_/\  __//\ \L\ \ \ \//\ \L\ \
       \ \_\ \_\/\____\/\____\ \____\ \____ \ \_\\ \____/
        \/_/\/_/\/____/\/____/\/____/\/___L\ \/_/ \/___/
                                       /\____/
                                       \_/__/


   Notes on building the MinGW/Cygwin version of Allegro.

   Written by Henrik Stokseth.

   Robert J Ohannessian added some updates to the installation instructions
   and an example on how to use Dev-C++ with Allegro.

   Elias Pschernig and Hein Zelle revamped the cross-compilation section.

   Andrei Ellman updated the Cygwin section.

   Michal Molhanec simplified the Dev-C++ instructions.

   See readme.txt for a more general overview.

MinGW notes

This is a complete MinGW port of Allegro. This build doesn't rely on the DLL files produced by MSVC any longer but can make them itself. I'm proud to say Allegro can now make Win32 programs entirely using free professional tools. On that note I'd like to thank Peter Puck for making this a reality and for finishing off what I started. Enjoy!

The screensaver example is built, but you must copy scrsave.scr to your windows/system directory (or winnt/system32 directory under Windows NT/2k/XP) if you want to test it.

If you have both GNU bash and GNU fileutils installed on your system, then set the environment variable UNIX_TOOLS (set UNIX_TOOLS=1). This is needed because GNU make will automatically use sh.exe instead of command.com if it finds it somewhere in the PATH. This step is not necessary when using MSYS or Cygwin as the makefile automatically sets UNIX_TOOLS for you.

"make depend" and "fixdll.bat" require that you have GNU sed installed. "fixdll.bat" requires that you have GNU sort (not DOS sort!) installed. You can download some extra utilities for MinGW from: 'http://sourceforge.net/projects/gnuwin32/'

Obtaining and installing the compiler & tools

You have four choices when it comes to installing MinGW and Allegro on your computer:

• The section 'Setting up MinGW to build Allegro' describes how to set up the MinGW command line tools which is the preferred choice for those who like to work on the command line.
• The section 'Setting up Dev-C++ to build Allegro' describes how to set up the Dev-C++ environment to work with Allegro. This is the preferred choice for those who like to work in a graphical development environment.
• The section 'Setting up Cygwin to build Allegro' describes how to set up your Cygwin compiler to build Allegro. Cygwin offers a mature Unix-like environment for you to work in.
• The last section 'Cross compilation' describes how to set up the MinGW command line tools to compile Win32 programs from your Linux box.

Setting up MinGW to build Allegro

The procedure is as follows:

1. Make sure you have a working MinGW installation. You can download the complete distribution or individual packages from 'http://www.mingw.org' or 'http://sourceforge.net/projects/mingw/'. You can also use the Minimal SYStem (MSYS) environment with Allegro.

2. Get the minimal DirectX 7 SDK for MinGW (dx70_mgw.zip). You download it from 'http://alleg.sourceforge.net/wip.html'. Note that this is *not* the same package as 'dx70_min.zip'. Unzip it to the compiler directory, overwriting any existing files.

3. Set the environment variable MINGDIR to the compiler directory. If you use Windows 9x, you can add the line

         set MINGDIR=c:\MinGW

to your 'c:\autoexec.bat' file, assuming 'c:\MinGW' is the compiler directory, and reboot. If you use Windows ME, you can run 'msconfig', select the 'Environment' tab and then add MINGDIR. If you use Windows NT/2k/XP, you can open the Control Panel, click the 'System' applet, the 'Advanced' tab and finally the 'Environment' button, and then add MINGDIR. If you use MSYS, add instead the line

         export MINGDIR=/mingw

to your 'c:\msys\etc\profile' file.

Test the installation by typing the following on the command line: 'gcc -v'. The answer should be similar to:

      Reading specs from ../lib/gcc-lib/mingw32/3.2/specs
      Configured with: ../gcc/configure --with-gcc --with-gnu-ld
      --with-gnu-as --host=mingw32 --target=mingw32 --prefix=/mingw
      --enable-threads --disable-nls --enable-languages=f77,c++,objc,ada
      --disable-win32-registry --disable-shared
      Thread model: win32
      gcc version 3.2 (mingw special 20020817-1)

Setting up Dev-C++ to build Allegro

Note: we assume that the complete version of the Dev-C++ environment (i.e with the bundled MinGW compiler) is used. If you use instead Dev-C++ as a mere IDE on top of an already installed MinGW compiler, follow the instructions given in the previous section.

The procedure is as follows:

1. Make sure you have a working Dev-C++ installation. You can download the complete version from 'http://bloodshed.net/dev/devcpp.html'.

2. Get the DirectX SDK: go to Tools\Check for Updates/Packages... and install the DirectX package. Close Dev-C++.

3. Add 'c:\DevCpp\bin' to the beginning of your PATH environment variable and set the environment variable MINGDIR to 'c:\DevCpp'. If you use Windows 9x, you can add the lines

         PATH=c:\DevCpp\bin;%PATH%
         set MINGDIR=c:\DevCpp

to your 'c:\autoexec.bat' file and reboot. If you use Windows ME, you can run 'msconfig', select the 'Environment' tab, then modify PATH and add MINGDIR. If you use Windows NT/2k/XP, you can open the Control Panel, click the 'System' applet, the 'Advanced' tab and finally the 'Environment' button, then modify PATH and add MINGDIR.

Test the installation by typing the following on the command line: 'gcc -v'. The answer should be similar to:

      Reading specs from ../lib/gcc-lib/mingw32/3.2/specs
      Configured with: ../gcc/configure --with-gcc --with-gnu-ld
      --with-gnu-as --host=mingw32 --target=mingw32 --prefix=/mingw
      --enable-threads --disable-nls --enable-languages=f77,c++,objc,ada
      --disable-win32-registry --disable-shared
      Thread model: win32
      gcc version 3.2 (mingw special 20020817-1)

Setting up Cygwin to build Allegro

The procedure is as follows:

1. Make sure you have a working Cygwin installation. You can download the setup.exe program from 'http://sources.redhat.com/cygwin/'. You will need the following packages: bash, binutils, cygwin, cygutils, fileutils, gcc, gdb, login, make, man, mingw-runtime, sed, sh-utils, texinfo, textutils and w32api.

2. Get the minimal DirectX 7 SDK for MinGW. (dx70_mgw.zip) Download it from 'http://alleg.sourceforge.net/wip.html' and unzip it to a temporary directory, for instance 'C:\Temp'. Then move the contents of 'C:\Temp\lib' to 'C:\cygwin\lib\w32api', and the contents of 'C:\Temp\include' to 'c:\cygwin\usr\include\w32api'. If you are asked if you want to overwrite any existing files, choose to overwrite them.

3. Put the following text in '/etc/profile' (c:\cygwin\etc\profile)

         export ALLEGRO_USE_CYGWIN=1
         export MINGDIR=/usr/local
         export CPATH=/usr/local/include
         export LIBRARY_PATH=/usr/local/lib

Note: if the CPATH or LIBRARY_PATH variables are already set, you will have to append the new path to the existing one by using a colon (":") as the separator.

Test the installation by typing the following in the Bash shell: 'gcc -v'. The answer should be similar to:

      Reading specs from /usr/lib/gcc-lib/i686-pc-cygwin/3.2/specs
      gcc version 3.2 20020927 (prerelease)

Cross compilation

The procedure is as follows:

1. Download and install the MinGW cross-compiler. You can get the software:

• directly from the MingW site: http://sourceforge.net/projects/mingw/. You need the following packages (as of February 2003):
  • gcc (gcc-3.2.2-20030208-1-src.tar.gz)
  • binutils (binutils-2.13.90-20030111-1-src.tar.gz)
  • mingw runtime (mingw-runtime-2.4.tar.gz)
  • w32api (w32api-2.2.tar.gz)
  Optionally, you can get from the SDL site, http://www.libsdl.org/extras/win32/common: opengl-devel (opengl-devel.tar.gz)
• using a more convenient script with instructions for downloading: http://www.libsdl.org/extras/win32/cross/README.txt. Follow the instructions, and make sure to edit the build-crosh.sh script so it downloads the most recent version of gcc and binutils.
• as a premade Debian package called 'mingw32', which you can install with 'apt-get install mingw32'.

2. Get the minimal DirectX 7 SDK for MinGW (dx70_mgw.zip). Download it from 'http://alleg.sourceforge.net/wip.html' and unzip it in the cross-compiler base directory. Make sure you convert all text files to unix style (unzip -a) or the preprocessor will croak. The DirectX package downloaded and installed by the SDL script is not up to date: replace it with the package from the Allegro site.

3. Edit the file 'xmake.sh' in the root of your Allegro directory, replacing XC_PATH, XPREFIX and INSTALL_BASE with the right names. For example, if your compiler's base dir (the one with bin, lib and include sub-folders) is /usr/i586-mingw32msvc, and you have prefix-less binaries in /usr/i586-mingw32msvc/bin, you would use:

         XC_PATH=/usr/i586-mingw32msvc/bin
         XPREFIX=
         INSTALL_BASE=/usr/i586-mingw32msvc

Note that the build-cross.sh script from SDL installs binaries both with and without prefix, but some binaries (windres specifically) are installed only with prefix. If you installed the crosscompiler in /opt/cross-tools using this script, you would use:

         XC_PATH=/opt/cross-tools/i386-mingw32msvc/bin:/opt/cross-tools/bin
         XPREFIX=i386-mingw32msvc-
         INSTALL_BASE=/opt/cross-tools/i386-mingw32msvc

4. Run './fix.sh mingw --dtou' (--dtou is only needed if your Allegro directory has text files in DOS format, otherwise you can use --quick). If you are using a SVN version of Allegro, run 'make depend' to generate the build dependencies, then run 'misc/fixdll.sh' to generate the allegro.def file. You are now finished with all the preparations.

5. You can now run './xmake.sh' to build the Allegro library and then run './xmake.sh install' as root to install it. Afterwards, you can use 'xmake.sh' as you would use 'make' to compile your Allegro programs, or you can use the 'cross-make.sh' and 'cross-configure.sh' scripts from the SDL site. You must use 'xmake.sh' to compile Allegro itself though.

6. To build the documentation, use the native build process. This limitation will eventually be removed.

Installing Allegro

This assumes you have unzipped allegro to c:\allegro or, if you are using MSYS, you have unzipped it to c:\msys\allegro (which is equivalent to /allegro from within the MSYS environment) or, if you are using Cygwin, you have unzipped it to c:\cygwin\allegro (which is equivalent to /allegro from within the Cygwin environment).

First configure Allegro for MinGW. Unless you are using MSYS or Cygwin, enter the following on the commandline (click on 'Start -> Run' then type "command" or "cmd" to get a command prompt):

      cd c:\allegro
      fix.bat mingw

      cd /allegro
      ./fix.sh mingw --dtou   (--dtou can be replaced by --quick for MSYS).

      make (or mingw32-make if you are using a recent version of MinGW)

      make STATICLINK=1

      make DEBUGMODE=1 (dynamically linked)
      make DEBUGMODE=1 STATICLINK=1 (statically linked)
      make PROFILEMODE=1 (dynamically linked)
      make PROFILEMODE=1 STATICLINK=1 (statically linked)

CROSSCOMPILE

Set this if you are crosscompiling; it implies UNIX_TOOLS.

WARNMODE

Set this if you want Allegro to display and stop on nearly all warnings issued by the compiler. Allegro should compile fine with this set.

TARGET_ARCH_COMPAT or TARGET_ARCH_EXCL

These affect the level of processor dependant optimisation that Allegro uses. You can set either of these to the processor type you want to optimize for. The difference between these two is that TARGET_ARCH_COMPAT optimise for the given processor so that the code will still run on older processors, while TARGET_ARCH_EXCL will generate code that will run exclusively on the given processor and of course newer ones. Example: set TARGET_ARCH_COMPAT=i686

TARGET_OPTS

Affects the general optimisations that Allegro uses.

UNIX_TOOLS

If your system does not have the usual DOS tools available (`md', `rd', `copy', etc., and commands which understand the \ character), then set this to 1 to use the Unix equivalents. This is set implicitly when you set CROSSCOMPILE, and is also set automatically when you are running under bash.

To activate any of these, type (for example) "make WARNMODE=1".

If your copy of Allegro does not include the linker .def file (unlikely, unless you have run "make veryclean" at some point, or are using the SVN version of Allegro), you can regenerate it by running "misc\fixdll.bat". You will need to have GNU sed and sort installed for this operation to work. The version of sed that is linked from the MinGW site does not work properly; it has issues with end-of-line characters. You should get sed and sort from the link at the top of this document.

Once the build is finished you can recover some disk space by running "make compress", which uses the UPX program to compress the executable files and the optimized dll. Before running "make compress", you must set the environment variable UPX_BIN to point to upx.exe. You will have to do run "make compress" before "make install" if you want the compressed dll to be copied to the windows directory. To recover even more disk space, you can run "make clean" to get rid of all the temporary files and HTML format documentation.

And then the last thing, installing the library. Run:

      make install

You have now installed Allegro! See the rest of the documentation and examples to learn more about it.

Using Allegro

All the Allegro functions, variables, and data structures are defined in allegro.h. You should include this in your programs, and link with either the optimised library liballeg.a, the debugging library liballd.a, or the profiling library liballp.a. You should include the Allegro DLLs in any software you release to the public.

When using a statically linked library, you must define the preprocessor symbol ALLEGRO_STATICLINK before including any of the Allegro headers and link your program against Allegro and the main Win32/DirectX libraries in that order (see the variable LIBRARIES in makefile.mgw). The names of the statically linked Allegro libraries are post-fixed with '_s' so that you will link with either liballeg_s.a, liballd_s.a or liballp_s.a.

Don't forget that you need to use the END_OF_MAIN() macro right after your main() function.

Compiling manually with MinGW

A simple example of a command line to compile an Allegro program with MinGW looks like:

      gcc foo.c -Wl,--subsystem,windows -O2 -Wall -o foo.exe -lalleg

      gcc foo.c -Wl,--subsystem,windows -mno-cygwin -O2 -Wall -o foo.exe -lalleg

Creating a program with Dev-C++

A simple example on how to create a little program with Dev-C++:

Launch Dev-C++ and create a new project (File/New Project). Select "Windows Application", then click on the "Ok" button. Name your project and give associate it to a new file. You should now see a sample code in a window. Close that window since you won't be needing it (Allegro is much simpler to use than this). Create a new file (File/New Source File), then write a small Allegro program. You can inspire yourself by the Allegro examples if you wish. Here's a small program you can type to see if everything worked until now:

      #include <allegro.h>

      int main() {
         allegro_init();
         allegro_message("Hello World!");
         return 0;
      }
      END_OF_MAIN()

Compile your project! Simply click on the green check mark on your Dev-C++ toolbar. Correct any syntax errors in your code, then click on "Execute" to run the program. If all worked you will see a message box pop up with "Hello World" inside of it.

Happy coding!