update docs for incoming params

docs/developers/android_service.md

@@ -8,3 +8,39 @@ BRouter exposes an [Android
 Service](https://developer.android.com/guide/components/services) which can be
 used by other applications to calculate routes. See `IBRouterService.aidl` for
 the interface definition.
+
+
+## Some words on the input rules (app and server)
+
+We have some parts of input:
+
+### lonlats
+
+The lonlats parameter is a list of positions where the routing should go along. It is recommended to use this instead of the two parameter lons and lats.
+
+When there are more than two points the 'via' points may be off the perfect route - in lower zoom level it is not always clear if a point meets the best way.
+
+The profile parameter 'correctMisplacedViaPoints' tries to avoid this situation.
+
+On the other hand, it would be fatal if this point is not reached when you want to go there.
+There are to choices to manage that:
+- add a poi to the 'pois' list
+- name the point in lonlats list
+
+Another feature of BRouter is routing via beelines.
+Define a straight starting point in the 'lonlats' list with a 'd' (direct). The second point needs no declaration.
+
+This contradicts the naming rules in 'lonlats'. If the point is to be given a name, the router parameter 'straight' can be used instead and filled with the index of the point.
+
+'nogos', 'polylines' and 'polygons' are also lists of positions.
+Please note: when they have a parameter 'weight' the result is not an absolute nogo it is weighted to the other ways.
+
+### routing parameter
+
+This parameters are needed to tell BRouter what to do.
+
+### profile parameter
+
+Profile parameters affect the result of a profile.
+For the app it is a list of params concated by '&'. E.g. extraParams=avoidferry=1&avoidsteps=0
+The server calls profile params by a prefix 'profile:'. E.g. ...&profile:avoidferry=1&profile:avoidsteps=0

docs/developers/http_server.md

@@ -14,3 +14,5 @@ BRouter HTTP server for various platforms.
 
 The API endpoints exposed by this HTTP server are documented in the
 `ServerHandler.java`
+
+Please see also [IBRouterService.aidl](./android_service.md) for calling parameter.