Louis - you have the right idea. Take a look at nanoX's server/drivers/scr_dos.c for
the int10 driver. The pixel drawing can be considerably optimized if we know that
the int10 framebuffer is at segment 0xa000 and we're running in 4 or 8 bpp mode...
FP_OFF(ScreenBuffer) = y*linesize + x;
*ScreenBuffer = c;
Greg
On Tuesday, May 11, 1999 6:01 PM, Louis P. Santillan [SMTP:[EMAIL PROTECTED]]
wrote:
> Using INT 0x10 gives a way for the driver to be implemented in very
> "portable" code though it would run much slower. Using the Mode 0x13
> frame buffer over INT 0x10 usually yields 2x speed improvement
> (minimal). However, the portable code look a little like this:
>
> /*
> This is not a real method in NanoX but has the same functionality
> as one that is in NanoX.
> Would set a pixel "portably"
> */
> void NG_PutPix( GRAPHICS g, unsigned short x, unsigned short y,
> COLOR c )
> {
> if( g == VIEWABLE_SCREEN )
> {
> union regs r;
>
> r.x.ax = DRAW_PIXEL_FUNCTION;
>
> r.x.bh = VIDEO_PAGE_0;
>
> r.x.bl = c->toInt();
>
> r.x.dx = ( ( x < SCREEN_WIDTH ) ? x : SCREEN_WIDTH );
>
> r.x.cx = ( ( y < SCREEN_HEIGHT ) ? y : SCREEN_HEIGHT );
>
> int86( VIDEO_INTERRUPT, &r, &r );
> }
> else
> {
> g->buffer[ y ][ x ] = c->toInt();
> }
> }
>
> /*
> I cant tell you if this code actually works...but similar would
> probly be best
> */
>
>
> Louis
>
> On Tue, 11 May 1999, Luke (boo) Farrar wrote:
>
> >
> >
> >
> > On Tue, 11 May 1999, Eric J. Korpela wrote:
> >
> > >
> > > > o MSDOS driver support. I wrote a 640x480x16 color driver in about 45 minutes.
> > > >NanoX now runs on DOS! (OK, I did this only to see how portable nanoX
> > > >is, and the
> > > >mouse driver still isn't written) This still uses MSC graphics library.
> > > >I'll have the bios
> > > >int10 version driver done shortly, which will allow nanoX to run on
> > > >ELKS! We should
> > > >have an ELKS version shortly... BTW, the nanoX kernel is around 20k on DOS...
> > >
> > > Does anyone else agree with me that direct int 10 access is a mistake?
> > > Wouldn't access through a device driver be a bit more unixy? It would
> > > be able to prevent multiple processes from trying to access int 10 services.
> > >
> > > Eric
> > >
> > >
> > >
> > What are the major bonuses of Int10 over the device driver? (If any).
> > Luke(Boo) Farrar.
> >
> >
> >
> >
>
