[Freeciv-Dev] Re: (PR#4781) phantom units?

["Gregory Berkolaiko" <Gregory.Berkolaiko@xxxxxxxxxxxx>]

On Thu, 7 Aug 2003, Jason Short wrote:

> Christian Knoke wrote:
> > On Thu, Aug 07, 2003 at 12:31:22PM -0700, Guest wrote:
> > 
> >>Sometimes enemy units are visible, but aren't really there. That is, my
> >>units can move through them even though I don't have an alliance or
> >>whatisit with that player. When my unit is 'on top' of it, it does
> >>appear in the sidebar like one of my own units would, I can't activate
> >>it however. When I capture the city that supports it, the unit is listed
> >>there, again unable to be activated. They are 'real' insofar that the
> >>Goto function will not plan a route through them (annoying if they are
> >>on a landbridge) and if the unit I request a Goto for is on top of such
> >>a phantom unit, it fails for every destination.
> >>I'm using CVS of 7-8-3 now, but this bug has been around for at least a
> > 
> > That is 7 AUG 2003 or 8 JUL 2003 ? Should have been gone with newest CVS,
> > but maybe occurs only less often?
> 
> Why would it be gone with the newest CVS?  I don't think we've done 
> anything to fix it...although it's hard to tell.
> 
> I've seen this problem for months, but have had no luck tracking it 
> down.  We need a savegame that can reliably reproduce it.

Yes, a savegame is almost a must.

This the why the bug is there: at some point when enemy units moves away 
either
(1) the client forgets to remove it from it's map
or
(2) the server forgets to inform the client

Why GOTO reacts as it does: the client think the unit is there and the 
goto uses the client information to plan the route.

G.