/*
 * some notes for optimizing m68k-code in C:
 *
 ******
 *
 *  short int c;
 *  for (c = n - 1; c >= 0; c--);
 *
 *  produces dbra
 *
 ******
 *
 *  int c;
 *  for (c = n - 1; c >= 0; c--);
 *
 *  produces swap/dbra/swap/dbra
 *  or dbra/dbra
 *
 ******
 *
 * some notes on the cpu:
 *
 *  asm: -(a0) is faster than (a0)+
 *  C  : *--a  is faster than *a++
 *
 *  asm: add/sub doesn't matter
 *  C  : a++/++a/a--/--a doesn't matter
 *
 ******
 *
 * fast linear-time integer log2
 *
 *  __inline extern int
 * ilog2(int in)
 * {
 *   register int lg __asm__ ("d0");
 *   register const int tt = 32;
 * 
 *   __asm ("bfffo	%1{#0,%2},%0
 * 	sub%.l	%2,%0
 * 	not%.l	%0"
 * 	: "=d" (lg)
 * 	: "m<>d" (in)
 * 	, "d" (tt)
 * 	: "cc");
 *   return lg;
 * }
 */

/*
 * Note that you'll usually have to flip Y coordinates since Mesa's
 * window coordinates start at the bottom and increase upward.  Most
 * window system's Y-axis increases downward
 *
 * See dd.h for more device driver info.
 * See the other device driver implementations for ideas.
 *
 */

/*
 * The Drawing area is defined by:
 * 
 * CC.Viewport.X = x;
 * CC.Viewport.Width = width;
 * CC.Viewport.Y = y;
 * CC.Viewport.Height = height;
 */

/*
 * Implementions of new drawing rutines:
 * 
 * you implement a own init for your rutines/hardware
 * and make some test and calls it from AmigaMesaCreateContext()
 * (look in the file src/amigamesa.c I'll thing you get it)
 * Be sure to fill this three ponters out:
 * void (*InitDD)( void );                                 // keep track of witch drawing rutines should be used
 * void (*Dispose) (amigaMesaContext *c);  // Use this when AmigaMesaDestroyContext is called 
 * void (*SwapBuffer) (void);                              // Use this when AmigaMesaSwapBuffers is called 
 * where InitDD sets the DD structure in orginal mesa with pointers to drawing rutines
 * Dispose is called when someone quits/closes down your made inits
 * SwapBuffer is called when one is changing buffer in dubble buffering mode
 * 
 * Write nice drawing rutines like those in src/amigamesa.c on make sure
 * that it's those you set in your InitDD rutine.
 * 
 * Add enum for your drawingmode for the taglist and if you need more tags also implement them
 * If posible some autodetection code in AmigaMesaCreateContext
 * Add enums and error codes if you neads 
 * 
 * PUT ALL YOUR NEADED DATA IN amigamesa_context->(void *)data in for your gfx driver
 * private structure.
 * 
 * Send the code to me and I will include it in the main code.
 */