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 Simple DirectMedia Layer for Nintendo DS

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 -Requirements-

 * The devkitpro SDK available at http://devkitpro.org.

   Read the information at http://devkitpro.org/wiki/Getting_Started/devkitARM

   The necessary packages are devkitARM, libnds, libfat and default arm7.

 * Optionally, use a DS emulator, such as desmume (http://desmume.org/)

   to program and debug.

 -Building SDL-

 After setting the devkitpro environment, cd into your SDL directory and type:

   make -f Makefile.ds

 This will compile and install the library and headers into the

 devkitpro's portlibs directory (../portlibs/arm/lib/ and

 ../portlibs/arm/include/). Additionally it will compile several tests

 that you can run either on the DS or with desmume. For instance:

   desmume --cflash-path=test/ test/nds-test-progs/testsprite2/testsprite2.nds

   desmume --cflash-path=test/ test/nds-test-progs/testspriteminimal/testspriteminimal.nds

   desmume --cflash-path=test/ test/nds-test-progs/testscale/testscale.nds 

   desmume test/nds-test-progs/general/general.nds

 -Notes-

 * The renderer code is based on the gl like engine. It's not using the sprite engine.

 * The hardware renderer is using the parts of the libgl2d abstraction library that can be found at:

     http://rel.phatcode.net/junk.php?id=117

   Used with the author's permission.

 * The port is very basic and incomplete:

   - SDL currently has to be compiled for either framebuffer mode or renderer mode.

      See USE_HW_RENDERER in Makefile.ds.

   - some optional renderer functions are not implemented.

   - no sound

 -Limitations-

 * in hardware renderer mode, don't load too many textures. The internal format is

   2 bytes per pixel. And there is only 256KB reserved for the textures. For instance,

   testscale won't display sample.bmp, unless it's resized to a smaller picture.

 * the screen size is 256 x 384. Anything else won't work.

 * there is no 8 bits/pixel mode because SDL 2.0 doesn't support palettes.

 -Joystick mapping-

 The Joystick presented to SDL has 2 axes and 8 buttons

  KEY      | Code

   A       |   0

   B       |   1

   X       |   2

   Y       |   3

   L       |   4

   R       |   5

   select  |   6

   start   |   7

  Left-right is axe 0.

  Up-down is axe 1.

 -Mouse mapping-

 todo

 -Examples-

 Due to memory limitations, to be able to successfully run the testscale example, sample.bmp must be resized to 256x105.