[Freeciv-Dev] Re: Waypoints for path-finding

[Gregory Berkolaiko <Gregory.Berkolaiko@xxxxxxxxxxxx>]

On Mon, 31 Mar 2003, Raimar Falke wrote:

> On Mon, Mar 31, 2003 at 06:26:16PM +0100, Gregory Berkolaiko wrote:
> > On Mon, 31 Mar 2003, Raimar Falke wrote:
> > 
> > > I want to convert the client goto (remove client/goto.c). It was
> > > decided that I should preserve the waypoints-feature. So we have to
> > > add waypoint support to the path finding. Suggested interface:
> > > 
> > > struct pf_path *pft_get_path(const struct pf_parameter *const parameter,
> > >                        int end_x, int end_y,
> > >                              int num_waypoints,
> > >                              struct map_position *waypoints);
> > > 
> > > Reasons: a naive implementation creates a new map for every part
> > > (start-1st waypoint, 1st-2nd,...) and assembles the paths together at
> > > the end. I think this may be done without internal knowledge and so
> > > can be placed in pft.
> > 
> > Mmm, now that a little bird told me that I am expected to write this 
> > function, I started looking for excuses and found them!
> > 
> > This function will be no use in client because of how the waypoints work 
> > now (and it's certainly nice and should stay this way):  you add waypoints 
> > "dynamically", the map is recalculated each time you hit "g" and then the 
> > little white path is displayed from the position of your last waypoint to 
> > where your mouse is.
> > 
> > Try it, you'll see.
> 
> I know and I want to preserve the current behavior. I don't see the
> connections.

This is how the current behaviour functions:
1. user hits "g"
2. goto map from the unit position is generated
3. user moves mouse, the goto line from the unit position to the mouse 
   location is drawn
4. user hits "g" (to add a waypoint)
5. goto map from the waypoint position is generated
6. user moves mouse, the goto line from the waypoint position to the mouse 
   location is drawn
7. loop to 4

For details see insert_waypoint and around.

How do you plan to change it and at which stage you would call the 
function
 struct pf_path *pft_get_path(const struct pf_parameter *const parameter,
                              int end_x, int end_y,
                              int num_waypoints,
                              struct map_position *waypoints);
?

G.