Difference between revisions of "Didj and Explorer libSDL"

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To build SDL, first download and unpack it:
 
To build SDL, first download and unpack it:
  
 +
<code>
 
   wget http://www.libsdl.org/release/SDL-1.2.13.tar.gz
 
   wget http://www.libsdl.org/release/SDL-1.2.13.tar.gz
 
   tar -xf SDL-1.2.13.tar.gz
 
   tar -xf SDL-1.2.13.tar.gz
 
   cd SDL-1.2.13
 
   cd SDL-1.2.13
 +
</code>
  
 
You'll need a toolchain, for example [[Didj_Build_Environment|this one]]
 
You'll need a toolchain, for example [[Didj_Build_Environment|this one]]
  
Now try the following, but replace the "/path/to" lines with paths on your system.  You'll want to tell the build system where to install libSDL and where to look for kernel headers:
+
Now try the following, but replace the "/path/to" lines with paths on your system.  You'll want to tell the build system where to install libSDL and where to look for kernel headers  
  
  CFLAGS="-I/path/to/kernel/linux-2.6/include/" CC=arm-linux-uclibcgnueabi-gcc CXX=arm-linux-uclibcgnueabi-g++ ./configure --prefix=/path/to/rootfs//usr/ --build=`uname -m` --host=arm-linux --disable-video-opengl --disable-video-x11 --disable-esd --disable-video-directfb --enable-video-fbcon
+
<code>
 +
CFLAGS="-I/path/to/kernel/linux-2.6/include/"  
 +
CC=arm-linux-uclibcgnueabi-gcc
 +
CXX=arm-linux-uclibcgnueabi-g++  
 +
./configure --prefix=/path/to/rootfs//usr/ --build=`uname -m` --host=arm-linux --disable-video-opengl --disable-video-x11  
 +
--disable-esd --disable-video-directfb --enable-video-fbcon --enable-pulseaudio=no
 +
 
 +
</code>
  
 
If that succeeds, try building and installing:
 
If that succeeds, try building and installing:
  
 +
<code>
 
   make
 
   make
 
   make install
 
   make install
 +
</code>
  
 
You should see libSDL.so in usr/lib in your rootfs directory as well as its header files in "usr/include".  When building applications against libSDL, tell the compiler to look for headers and the linker to look for libraries there (ie: CFLAGS="-I/path/to/rootfs/usr/include" and LDFLAGS="-L/path/to/rootfs/usr/lib").
 
You should see libSDL.so in usr/lib in your rootfs directory as well as its header files in "usr/include".  When building applications against libSDL, tell the compiler to look for headers and the linker to look for libraries there (ie: CFLAGS="-I/path/to/rootfs/usr/include" and LDFLAGS="-L/path/to/rootfs/usr/lib").

Revision as of 19:36, 22 July 2010

libSDL is a popular library for games and other applications. It provides APIs for events (buttons, etc), graphics, sound, and more.

Build the library

To build SDL, first download and unpack it:

 wget http://www.libsdl.org/release/SDL-1.2.13.tar.gz
 tar -xf SDL-1.2.13.tar.gz
 cd SDL-1.2.13

You'll need a toolchain, for example this one

Now try the following, but replace the "/path/to" lines with paths on your system. You'll want to tell the build system where to install libSDL and where to look for kernel headers

CFLAGS="-I/path/to/kernel/linux-2.6/include/" 
CC=arm-linux-uclibcgnueabi-gcc
CXX=arm-linux-uclibcgnueabi-g++ 
./configure --prefix=/path/to/rootfs//usr/ --build=`uname -m` --host=arm-linux --disable-video-opengl --disable-video-x11 
--disable-esd --disable-video-directfb --enable-video-fbcon --enable-pulseaudio=no

If that succeeds, try building and installing:

 make
 make install

You should see libSDL.so in usr/lib in your rootfs directory as well as its header files in "usr/include". When building applications against libSDL, tell the compiler to look for headers and the linker to look for libraries there (ie: CFLAGS="-I/path/to/rootfs/usr/include" and LDFLAGS="-L/path/to/rootfs/usr/lib").

Set up the device

Copy the .so files and symlinks to your device. Also edit "/etc/profile" on your device and add some environment variables for SDL:

For Didj:

 export SDL_NOMOUSE=1
 export SDL_FBDEV="/dev/fb0"
 export SDL_VIDEODRIVER="fbcon"
 export SDL_AUDIODRIVER="dsp"
 export SDL_PATH_DSP="/dev/dsp"
 export SDL_DEBUG="1"
 export SDL_FBACCEL="0"

For Explorer, the touchscreen works sort of like a mouse (TODO: add tslib support?), so you could try:

 export SDL_MOUSEDEV="/dev/input/event3"
 export SDL_FBDEV="/dev/fb0"
 export SDL_VIDEODRIVER="fbcon"
 export SDL_AUDIODRIVER="dsp"
 export SDL_PATH_DSP="/dev/dsp"
 export SDL_DEBUG="1"
 export SDL_FBACCEL="0"

You'll need to source that on your device:

 . /etc/profile

or just reboot. You should now be able to run SDL programs or demos as long as your device is set up with a standard Linux framebuffer and console in place of the LeapFrog-supplied graphics drivers.

TODO

* better audio support?
* tslib to make touchscreen usable on Explorer?