Sophie: allegro-devel-4.4.1.1-2ark x86

allegro-devel-4.4.1.1-2ark.x86_64.rpm

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd">
<html><head><title>
Allegro Manual: Reducing your executable size
</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="stylesheet" title="Default" type="text/css" href="allegro.css"></head><body bgcolor=white text=black link="#0000ee" alink="#ff0000" vlink="#551a8b">
<h1><a name="Reducing your executable size">Reducing your executable size</a></h1>

<p>
Some people complain that Allegro produces very large executables. This is 
certainly true: with the DJGPP version, a simple "hello world" program will 
be about 200k, although the per-executable overhead is much less for 
platforms that support dynamic linking. But don't worry, Allegro takes up a 
relatively fixed amount of space, and won't increase as your program gets 
larger. As George Foot so succinctly put it, anyone who is concerned about 
the ratio between library and program code should just get to work and write 
more program code to catch up :-)

<p>
Having said that, there are several things you can do to make your programs 
smaller:
<ul><li>
For all platforms, you can use an executable compressor called UPX, which
is available at <a href="http://upx.sourceforge.net/">http://upx.sourceforge.net/</a>. This usually manages a
compression ratio of about 40%.
<li>
When using DJGPP: for starters, read the DJGPP FAQ section 8.14, and take
note of the -s switch. And don't forget to compile your program with
optimisation enabled!
<li>
If a DOS program is only going to run in a limited number of graphics modes, 
you can specify which graphics drivers you would like to include with the 
code:
<blockquote class="code"><pre>
   BEGIN_GFX_DRIVER_LIST
      driver1
      driver2
      etc...
   END_GFX_DRIVER_LIST
</pre></blockquote>
where the driver names are any of the defines:
<blockquote class="text"><pre>
   GFX_DRIVER_VBEAF
   GFX_DRIVER_VGA
   GFX_DRIVER_MODEX
   GFX_DRIVER_VESA3
   GFX_DRIVER_VESA2L
   GFX_DRIVER_VESA2B
   GFX_DRIVER_XTENDED
   GFX_DRIVER_VESA1
</pre></blockquote>
This construct must be included in only one of your C source files. The 
ordering of the names is important, because the autodetection routine works 
down from the top of the list until it finds the first driver that is able 
to support the requested mode. I suggest you stick to the default ordering 
given above, and simply delete whatever entries you aren't going to use.
<li>
If your DOS program doesn't need to use all the possible color depths, you 
can specify which pixel formats you want to support with the code:
<blockquote class="code"><pre>
   BEGIN_COLOR_DEPTH_LIST
      depth1
      depth2
      etc...
   END_COLOR_DEPTH_LIST
</pre></blockquote>
where the color depth names are any of the defines:
<blockquote class="text"><pre>
   COLOR_DEPTH_8
   COLOR_DEPTH_15
   COLOR_DEPTH_16
   COLOR_DEPTH_24
   COLOR_DEPTH_32
</pre></blockquote>
Removing any of the color depths will save quite a bit of space, with the 
exception of the 15 and 16-bit modes: these share a great deal of code, so 
if you are including one of them, there is no reason not to use both. Be 
warned that if you try to use a color depth which isn't in this list, your 
program will crash horribly!
<li>
In the same way as the above, you can specify which DOS sound drivers you 
want to support with the code:
<blockquote class="code"><pre>
   BEGIN_DIGI_DRIVER_LIST
      driver1
      driver2
      etc...
   END_DIGI_DRIVER_LIST
</pre></blockquote>
using the digital sound driver defines:
<blockquote class="text"><pre>
   DIGI_DRIVER_SOUNDSCAPE
   DIGI_DRIVER_AUDIODRIVE
   DIGI_DRIVER_WINSOUNDSYS
   DIGI_DRIVER_SB
</pre></blockquote>
and for the MIDI music:
<blockquote class="code"><pre>
   BEGIN_MIDI_DRIVER_LIST
      driver1
      driver2
      etc...
   END_MIDI_DRIVER_LIST
</pre></blockquote>
using the MIDI driver defines:
<blockquote class="text"><pre>
   MIDI_DRIVER_AWE32
   MIDI_DRIVER_DIGMID
   MIDI_DRIVER_ADLIB
   MIDI_DRIVER_MPU
   MIDI_DRIVER_SB_OUT
</pre></blockquote>
If you are going to use either of these sound driver constructs, you must 
include both.
<li>
Likewise for the DOS joystick drivers, you can declare an inclusion list:
<blockquote class="code"><pre>
   BEGIN_JOYSTICK_DRIVER_LIST
      driver1
      driver2
      etc...
   END_JOYSTICK_DRIVER_LIST
</pre></blockquote>
using the joystick driver defines:
<blockquote class="text"><pre>
   JOYSTICK_DRIVER_WINGWARRIOR
   JOYSTICK_DRIVER_SIDEWINDER
   JOYSTICK_DRIVER_GAMEPAD_PRO
   JOYSTICK_DRIVER_GRIP
   JOYSTICK_DRIVER_STANDARD
   JOYSTICK_DRIVER_SNESPAD
   JOYSTICK_DRIVER_PSXPAD
   JOYSTICK_DRIVER_N64PAD
   JOYSTICK_DRIVER_DB9
   JOYSTICK_DRIVER_TURBOGRAFX
   JOYSTICK_DRIVER_IFSEGA_ISA
   JOYSTICK_DRIVER_IFSEGA_PCI
   JOYSTICK_DRIVER_IFSEGA_PCI_FAST
</pre></blockquote>
The standard driver includes support for the dual joysticks, increased 
numbers of buttons, Flightstick Pro, and Wingman Extreme, because these are 
all quite minor variations on the basic code.
<li>
If you are _really_ serious about this size, thing, have a look at the top 
of include/allegro/alconfig.h and you will see the lines:
<blockquote class="code"><pre>
   #define ALLEGRO_COLOR8
   #define ALLEGRO_COLOR16
   #define ALLEGRO_COLOR24
   #define ALLEGRO_COLOR32
</pre></blockquote>
If you comment out any of these definitions and then rebuild the library, 
you will get a version without any support for the absent color depths, 
which will be even smaller than using the DECLARE_COLOR_DEPTH_LIST() macro. 
Removing the ALLEGRO_COLOR16 define will get rid of the support for both 15 
and 16-bit hicolor modes, since these share a lot of the same code.
</ul>
Note: the aforementioned methods for removing unused hardware drivers only 
apply to statically linked versions of the library, eg. DOS. On Windows and 
Unix platforms, you can build Allegro as a DLL or shared library, which 
prevents these methods from working, but saves so much space that you 
probably won't care about that. Removing unused color depths from alconfig.h 
will work on any platform, though.

<p>
If you are distributing a copy of the setup program along with your game, 
you may be able to get a dramatic size reduction by merging the setup code 
into your main program, so that only one copy of the Allegro routines will 
need to be linked. See setup.txt for details. In the DJGPP version, after 
compressing the executable, this will probably save you about 200k compared 
to having two separate programs for the setup and the game itself.



<p><br>
<hr><div class="al-back-to-contents"><a href="allegro.html">Back to contents</a></div>

</body>
</html>