{**********************************************************************}
{ Scroll smoothly in 100 column text screen using cursor keys		}
{ Quit on Escape key.							}
{**********************************************************************}

procedure smooth_text_scroll;
const
KEY_ESC = 	$1B;
KEY_UP	=	72;
KEY_DOWN =	80;
KEY_LEFT =	75;
KEY_RIGHT =	77;
KEY_ENTER =	$0D;
const
msg : string[53] = 'This is a text line in the new 100 column text buffer'; 
var
x,y,i,key : integer;
begin
	x := 0;
	y := 0;
	set_more_columns(100);	{ Select 100 text column mode		}
	set_cursor_position(0,0);
	for i := 0 to 99 do { Fill newly organized text buffer	}
	     write_string(i, 0, seg(msg), ofs(msg));
	repeat
		key := integer(readkey);
		case key of

		KEY_RIGHT:			{ Scroll right }
			if x < 799 then inc(x);
		KEY_LEFT:			{ Scroll left	}
			if x > 0 then dec(x);
		KEY_UP:			{ Scroll up	}
			if y > 0 then dec(y);
		KEY_DOWN:			{ Scroll down	}
			if y < 1399 then inc(y);
		end;
		smooth_scroll(x,y);
	until key = KEY_ENTER;
	smooth_scroll(0,0);

	{--- Set default text mode	}
	i := get_display_type;
	if i = MONO then set_mode(7)
	else	set_mode(3);
end;