[GraphHopper] Fwd: Re: instruction too early

[Peter]

ok. So what you would need some method like this:

currentInstruction = find(lat, lon, maxDistance, previousInstruction)

which can be called several times (and is cheap&fast) and only searches
e.g. forward for the closest instruction? Would this solve your issue?
Or would 'backward' search also be necessary as a user could go far off
the route?

Peter


On 17.02.2015 16:32, Laura Barroso wrote:
> well,yes, I can probably do that, but I was thinking that if my current
> location is near to one of the points that holds the instruction then I
> will miss it, am I right?...however will do your suggestion.Thanks.
> My usecase is guide the user depending on the gps current location and the
> route.
>
>> if you find once the next instruction why would you need to iterate over
>> all points, why not just take the first of this instruction (getFirstLat
>> etc) and check the distance? what is your usecase?
>>
>> Peter
>>
>>
>> On 17.02.2015 16:15, Laura Barroso wrote:
>>> you mean something like this?
>>> DistanceCalc distCalc = Helper.DIST_EARTH;
>>> 			distCalc.calcDist(instruction.getPoints().getLat(0),
>>> instruction.getPoints().getLon(0),					 currentLocation.getLatitude(),
>>> currentLocation.getLongitude())
>>>
>>> but still will have iterate over all the points inside the
>>> instruction...
>>> is there any better way????
>>>
>>>
>>>> Laura,
>>>>
>>>> why not find the next instruction and only display it if the current
>>>> location is close to it? No need to do unnecessary find() calls.
>>>>
>>>>> until the max distance between
>>>>> one of the edges and the current position is right, even is that mean
>>>>> that
>>>>> the user don't get any instruction at all
>>>> Why not specify the allowed maximum distance to the route in the find
>>>> method appropriately?
>>>>
>>>> Regards,
>>>> Peter
>>>>
>>>>
>>>> On 17.02.2015 14:43, Laura Barroso wrote:
>>>>> oh boy, so that's what's happening...this is not good for me, I'm not
>>>>> interested in knowing the next instruction until the max distance
>>>>> between
>>>>> one of the edges and the current position is right, even is that mean
>>>>> that
>>>>> the user don't get any instruction at all because he don't get close
>>>>> enough to them. ok, Thanks a lot for the clarification, now everything
>>>>> gets more sense.
>>>>> Thinking a good approach maybe override instructionList class in order
>>>>> to
>>>>> modify this behavior to suit my needs. Second approach: compute
>>>>> everything
>>>>> twice, one the instructionlist(in the find method) and the second on
>>>>> my
>>>>> method...
>>>>>
>>>>>> Hi Laura,
>>>>>>
>>>>>> I took a look at InstructionList.find() and actually found some
>>>>>> inconsistent behaviour:
>>>>>> https://github.com/graphhopper/graphhopper/issues/331
>>>>>>
>>>>>> Nevertheless I don't think this is the reason for the problems you
>>>>>> described.
>>>>>>
>>>>>> Maybe to avoid misunderstandings, the find(lat, lon, dist) method is
>>>>>> supposed to work as following:
>>>>>> Given lat,lon find the closest point on the route. If lat,lon is not
>>>>>> more than than dist away from the route, then it yields the upcoming
>>>>>> instruction (even if this instruction is a lot further away than
>>>>>> dist).
>>>>>>
>>>>>>> Easy: any point in Havana I have test routes in Miramar, Vedado and
>>>>>>> Guanabacoa, note those are like areas that are not close to each
>>>>>>> other(at
>>>>>>> list Guanabacoa from the rest), the last point that I test was:
>>>>>>> START:  latitud: 23.12529533541739 longitude: -82.41401873360883
>>>>>>> END: latitud: 23.124871881707463 longitude: -82.4237889156866
>>>>>>> The route that I create was on foot, for android purpose. Thanks!
>>>>>>>
>>>>>>>
>>>>>> To find the reason for your exact problem, it would help a lot if you
>>>>>> can also give me lat, lon coordinates for which you don't get any
>>>>>> instruction or the instruction within wrong distance.
>>>>>>
>>>>>> Cheers,
>>>>>> Jan
>>>>>>
>>>>>>>> Hi Laura,
>>>>>>>>
>>>>>>>> thanks for the clarification. i will take a look into this, but it
>>>>>>>> would
>>>>>>>> be helpfull if you can provide me start and end point of the route,
>>>>>>>> as
>>>>>>>> well as one or two points where there is a wrong instruction or one
>>>>>>>> missing.
>>>>>>>>
>>>>>>>> Jan
>>>>>>>>
>>>>>>>>> Hello, thanks for your reply, I was not referring to that issue
>>>>>>>>> but
>>>>>>>>> it
>>>>>>>>> is
>>>>>>>>> quite similar to was happen to me... however I know that
>>>>>>>>> graphhopper
>>>>>>>>> generate all the instructions for the route, I check it out every
>>>>>>>>> time.
>>>>>>>>> The problem is that it gives me the wrong instruction at the wrong
>>>>>>>>> time.
>>>>>>>>> The sniped code you see is part of the class that overrides
>>>>>>>>> MyLocationOverlay, on the onLocationChanged method.
>>>>>>>>> I tell graphhopper to give me the next instruction in this piece
>>>>>>>>> of
>>>>>>>>> code:
>>>>>>>>> Instruction instruction = il.find(location.getLatitude(),
>>>>>>>>> location.getLongitude(), 2);
>>>>>>>>> il is the InstructionList that is created as part of the route, I
>>>>>>>>> pass
>>>>>>>>> it
>>>>>>>>> to the class and every time that location changes I check if there
>>>>>>>>> is
>>>>>>>>> anything to say to the user.
>>>>>>>>> Hi Laura,
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>> Hello everyone: I notices that graphhopper is giving me the
>>>>>>>>>> instructions too early and sometimes it wont even give me
>>>>>>>>>> anything,
>>>>>>>>>> I think I read about an issue pointing that but now is close...
>>>>>>>>> maybe you refer to this issue
>>>>>>>>> https://github.com/graphhopper/graphhopper/issues/94 regarding
>>>>>>>>> missing
>>>>>>>>> instructions?
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>> I override MyLocationOverlay class, and this is my code:
>>>>>>>>>> @Override public void onLocationChanged(Location location) {
>>>>>>>>>> super.onLocationChanged(location);
>>>>>>>>>> if (lastLocation == null || location != lastLocation) {
>>>>>>>>>> lastLocation = location; if (il != null) { Instruction
>>>>>>>>>> instruction
>>>>>>>>>> = il.find(location.getLatitude(), location.getLongitude(), 2); if
>>>>>>>>>> (instruction != null && instruction !=
>>>>>>>>> lastInstruction) {
>>>>>>>>>> lastInstruction = instruction; String text =
>>>>>>>>> lastInstruction.getTurnDescription(esTR);
>>>>>>>>>> Toast.makeText(context, text,
>>>>>>>>> Toast.LENGTH_LONG).show();
>>>>>>>>>> if (tts != null) { tts.speak(text, TextToSpeech.QUEUE_FLUSH,
>>>>>>>>>> null); } } } } }
>>>>>>>>> I would take a look into this, but I don't understand yet where
>>>>>>>>> exactly
>>>>>>>>> your code hooks into the GraphHopper Code. I do not see any
>>>>>>>>> LocationOverlay class, but maybe you can point me there with a
>>>>>>>>> github
>>>>>>>>> link.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>> Note that it suppose to give me the instruction with at list 2
>>>>>>>>>> meters of distance, last time I check it gave me the instruction
>>>>>>>>>> with at list 5 meters of distance in the first edge...the next
>>>>>>>>>> turn
>>>>>>>>>> wont dispatch anything at all...what could be happening? My start
>>>>>>>>>> point now is branch "issue 314" since I haven't being able to
>>>>>>>>>> download the complete repository(problems with my connection).
>>>>>>>>>> any
>>>>>>>>>> help will be appreciated.
>>>>>>>>> Cheers,
>>>>>>>>> Jan
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>