Possible movement improvement

[Brian Dunn <bd1 at sysmatrix dot net>]

Both mplayer.c and iplayer.c have the following:

	    /* Try moving sideways. */
	    if (probability(80)) {
		dx = task->args[0] - unit->x;  dy = task->args[1] - unit->y;
		fact = (flip_coin() ? 50 : -50);
		x1 = unit->x - ((fact * dy) / 100);
		y1 = unit->y + ((fact * dx) / 100);
		if (inside_area(x1, y1)) {
			DMprintf("%s blocked, moving sideways to (%d, %d).", unit_desig(unit), x1, y1);
			net_push_move_to_task(unit, x1, y1, 1);
	    	}
	    }

This is called when a unit is blocked and could not perform a move_to task.

If I read the code correctly, it seems to only allow two of the possible four directions to be tried.  I have seen units get stuck behind 'C' shaped obstacles, and this may partly explain why.  A proposed change would be:

	fact = (flip_coin() ? 50 : -50);
		x1 = unit->x - ((fact * dy) / 100);
fact = (flip_coin() ? 50 : -50);  /* this line is new */
			y1 = unit->y + ((fact * dx) / 100);
	
This may allow the unit to try any of four directions randomly.

If this change makes sense, it will need to be in both mplayer.c and iplayer.c.


Brian