/* vscroll.c (emx+gcc) -- Copyright (c) 1987-1993 by Eberhard Mattes */

#include <stdlib.h>
#include <dos.h>
#define INCL_VIO
#include <os2emx.h>
#include <sys/video.h>
#include "video2.h"

void v_scroll (int tl_x, int tl_y, int br_x, int br_y, int count, int flag)
{
  if (count > 0)
    {
      if (_osmode == OS2_MODE)
        {
          BYTE cell[2];

          cell[0] = ' ';
          cell[1] = (BYTE)_v_attr;
          switch (flag)
            {
            case V_SCROLL_UP:
              VioScrollUp (tl_y, tl_x, br_y, br_x, count, cell, 0);
              break;
            case V_SCROLL_DOWN:
              VioScrollDn (tl_y, tl_x, br_y, br_x, count, cell, 0);
              break;
            case V_SCROLL_LEFT:
              VioScrollLf (tl_y, tl_x, br_y, br_x, count, cell, 0);
              break;
            case V_SCROLL_RIGHT:
              VioScrollRt (tl_y, tl_x, br_y, br_x, count, cell, 0);
              break;
            case V_SCROLL_CLEAR:
              VioScrollUp (tl_y, tl_x, br_y, br_x, 0xffff, cell, 0);
              break;
            }
        }
      else
        {
          union REGS r;

          r.h.al = count;
          switch (flag)
            {
            case V_SCROLL_UP:
              r.h.ah = 0x06;
              break;
            case V_SCROLL_DOWN:
              r.h.ah = 0x07;
              break;
            case V_SCROLL_LEFT:
            case V_SCROLL_RIGHT:
              return;
            case V_SCROLL_CLEAR:
              r.h.ah = 0x06;
              r.h.al = 0;
              break;
            }
          r.h.cl = (unsigned char)tl_x;
          r.h.ch = (unsigned char)tl_y;
          r.h.dl = (unsigned char)br_x;
          r.h.dh = (unsigned char)br_y;
          r.h.bh = (unsigned char)_v_attr;
          _int86 (0x10, &r, &r);
        }
    }
}