# `QuakeServer.Extensions.Routes`
[🔗](https://github.com/jaman/quake_server/blob/v0.1.0/lib/quake_server/extensions/routes.ex#L1)

FTE's `route_calculate` (`sv_move.c`): a path over the level's waypoints from where an
entity stands to a destination, handed to the program's callback at the start of the
next frame (`run/1`) as a list of nodes in allocated memory.

The waypoints are read once a level, the first time a route is asked for, from the
first of `data/<map>.way`, `bots/navigation/<map>.nav` and `maps/<map>.bsp.way` that
exists, in FTE's text form: a count, then for each waypoint `x y z radius links`
followed by `links` lines of `target cost flags`. With none, the level has no
waypoints.

The start and end waypoints are those nearest the entity and the destination, a
waypoint whose radius holds the point first, and otherwise only one the point can see
through the world model. The path is FTE's A* search over the links, leaving out links
with any of the deny flags.

The callback is `callback(entity, destination, count, nodes)`, `count` an integer;
`nodes` points at `count` records of five words: the place `x y z`, the flags of the
link that reaches it (an integer) and its radius. Record 0 is the destination (flags
`LF_DESTINATION`, radius 32), then the waypoints from the end back to the start, then
the entity's place (flags 0, radius 32): the last record is the first place to go.
Without a path the records are the destination and the entity's place, radius 0.

# `call`

```elixir
@spec call(map(), String.t(), non_neg_integer()) :: map()
```

Run `route_calculate`.

# `run`

```elixir
@spec run(QuakeServer.Server.t()) :: QuakeServer.Server.t()
```

Hand every route asked for since the last call to its callback, oldest first.

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*Consult [api-reference.md](api-reference.md) for complete listing*