[crossfire] move_allow attribute

[Mark Wedel]

Miguel Ghobangieno wrote:
> move_allow * would just add some more control over
> movement permissions so that one can more easily set
> what cannot and what can pass over the tile; more
> granularity.
> 
> Theoretically, after this is added, spells can be
> created (such as build bridge, which could set
> move_allow walk on the affected water tiles and then
> spawn brige arches forward (if spells were allowed on
> said tiles ofcourse) that can use modify permissions.
> I would suggest, however, that (specifically) a
> passwall spell not be given to players (could be used
> in fire-walls for some things though etc).

  Yes - that is basically correct.

  For things like water, this could be more easily done in existing code - water 
would allow swimming and/or boat movement.  So if the spell in question had the 
move_type of swimming, it could move over the water and create the bridge.

  But right now, walls block everything.  So by default, as the code is now, the 
spell can't move onto the wall to create the hole.  So if someone was to write 
it, they would have to change pieces of code to currently ignore the current 
move block logic.

  This could change if we add a movement type of ETHEREAL or the like (giving it 
to ghosts would be interesting) - the spell could be given the ethereal movement 
type to let is go through the walls to create the tunnels.

  That said, any such change would have to be carefully considered, as it could 
ruin many maps (or the default behavior be that walls continue to block 
everything by default)