Re: [AD] GGI patch for 3.9.21

[Michael Bukin <M.A.Bukin@xxxxxxxxxx>]

Shawn Hargreaves <shawn@xxxxxxxxxx> writes:

> Michael Bukin <M.A.Bukin@xxxxxxxxxx> writes:
> > There is an idea for GFX_SAFE mode which is explained with pseudo-code:
> 
> That's an interesting proposal, but not very portable because at least on 
> DOS, when I tried to do an automatic screen update with conversion using a 
> timer handler, it was very unstable and kept locking the machine. I don't 
> think that is quite safe enough to fit the name of the driver :-)

I like your other ideas about GFX_SAFE, but just for completeness, I
did not mean to make autoconversion in the timer.  It can be done with
wrappers for graphics primitives and bank switching.

void
_rectfill_wrapperXX (BITMAP *dst, int x1, int y1, int x2, int y2, int color)
{
  /* Clip x1, y1, x2, y2. */
  ...

  /* Turn off update magic for bank switching. */
  magic = FALSE;

  /* Call real rectfill (for writing to double-buffer). */
  _linear_rectfillXX (dst, x1, y1, x2, y2, color);

  /* Update region of screen. */
  _update_screen (real_screen, screen, x1, y1, x2 - x1 + 1, y2 - y1 + 1);

  magic = TRUE;
}

unsigned long
gfx_safe_write_line (BITMAP *bmp, int line)
{
  if (magic && (current_line != line)) {
    _update_screen (real_screen, screen, current_line, 0, SCREEN_W, 1);
  }
  current_line = line;
  return bmp->line[line];
}

-- 
Michael Bukin