[Loadstone] Routes and trips.

Shawn Kirkpatrick shawn at odyssey.cm.nu
Wed Oct 10 02:34:09 BST 2007

It sounds like you have an unusual dataset. Is this street data actually 
line segments? If so, then more useful things can be done with it. The 
percentage system for naming street points just doesn't scale propperly. It 
might work on a street 180m (metres? miles?) long with only 9 entries but 
try scaling that up to something like the transcanada highway that runs a 
couple thousand kilometres with who knows how many points and you run in to 
real problems. Your example table shows another problem, calculation 
slippage. The percentage increments aren't consistant.
This seems to be something different from trip or track mode. This would be 
something like a street mode, a way of representing streets. This would be 
nice but it'll be a rather hard feature to implement I think. Mainly because 
of the size of the datasets involved. The phone just doesn't have the power 
to process actual street data and do something useful with it. What we're 
doing for now is entering all the line data we have into a database on the 
pc and then having the computer calculate where those lines cross. This 
gives us intercection points and that's proved very useful.
If the data you have is or can be turned in to line segments then the same 
process could be applied to it.

On Tue, 9 Oct 2007, Cearbhall O Meadhra wrote:

> Sean,
> I am afraid I may have caused some confusion in my last message. The streets
> are given their percentage identity in the creation of the Loadstone file.
> For example, my source of the map data gives me a three column spread sheet
> in excel that contains one street name occurring nine times. (The street is
> 180m long). As each of the point names is thus identical, this is not a very
> useful way to present the point names. That is why we devised our own system
> of taking the point names in the order in which the source sends them to us
> and then applying the percentage value to the nine entries that were
> supplied in this example. This means that the Loadstone dataset already has
> the streets marked in a series of points identified by increasing percentage
> values.
> The point I was making was that if the street is not straight but actually
> looping around in a curve, this sequence of points might not be the same as
> that in which the points are encountered on the street. It would be very
> simple for the user to edit the percentage value on each point name using
> the "point update" feature in loadstone to get the right sequence manually
> as they move along the street. To make this easier, I would suggest that the
> point name be held in Loadstone as two cells so that the percentage value is
> contained in a scroll box. We store the total number of increments for each
> street as part of the process of creating the percentage values and this
> could easily be passed over to Loadstone as part of the input dataset. Thus
> the user could scroll through the percentage values until the right one was
> found. Once out of update mode the percentage would stay fixed.
> Here is a sample of the finished table ready for Loadstone:
> ------------------
> table,point
> Name,latitude,longitude,accuracy,satellites,priority,userid,id
> "MARTELLO TERRACE, 0%",532072000,-61017300,1,9,0,39208,1129506301
> "MARTELLO TERRACE, 13%",532072000,-61014400,1,9,0,39208,1129506302
> "MARTELLO TERRACE, 25%",532072000,-61011400,1,9,0,39208,1129506303
> "MARTELLO TERRACE, 38%",532070000,-61009000,1,9,0,39208,1129506304
> "MARTELLO TERRACE, 50%",532069000,-61007100,1,9,0,39208,1129506305
> "MARTELLO TERRACE, 63%",532072000,-61017300,1,9,0,39208,1129506306
> "MARTELLO TERRACE, 75%",532073000,-61014700,1,9,0,39208,1129506307
> "MARTELLO TERRACE, 88%",532073000,-61011900,1,9,0,39208,1129506308
> "MARTELLO TERRACE, 100%",532074000,-61007900,1,9,0,39208,1129506309
> "MAYFIELD TERRACE, 0%",531945000,-61069200,1,9,0,39208,1129505600
> "MAYFIELD TERRACE, 33%",531943000,-61069000,1,9,0,39208,1129505601
> "MAYFIELD TERRACE, 67%",531943000,-61069000,1,9,0,39208,1129505610
> "MAYFIELD TERRACE, 100%",531941000,-61068500,1,9,0,39208,1129505611
> "MEATH PLACE, 0%",532022000,-61015600,1,9,0,39208,1129506410
> "MEATH PLACE, 17%",532020000,-61013800,1,9,0,39208,1129506411
> "MEATH PLACE, 33%",532019000,-61013600,1,9,0,39208,1129506416
> "MEATH PLACE, 50%",532019000,-61013500,1,9,0,39208,1129506417
> "MEATH PLACE, 67%",532019000,-61013300,1,9,0,39208,1129506437
> "MEATH PLACE, 83%",532017000,-61012300,1,9,0,39208,1129506438
> "MEATH PLACE, 100%",532015000,-61010500,1,9,0,39208,1129506439
> ------------
> Does this still seem too complicated?
> All the best,
> Cearbhall
> "Good design enables - Bad design disables"
> Tel: 01-2864623 Mob: 087 9922227 Em: cearbhall.omeadhra at projectidd.ie
> -----Original Message-----
> From: loadstone-bounces at loadstone-gps.com
> [mailto:loadstone-bounces at loadstone-gps.com] On Behalf Of Shawn Kirkpatrick
> Sent: 09 October 2007 13:48
> To: loadstone at loadstone-gps.com
> Subject: Re: [Loadstone] Routes and trips.
> At first this system sounds like a good idea but unfortunately would be
> impossible to implement. This is because loadstone has no concept of
> streets, only points. We can actually get street line data for north america
> but the dataset is too big for the phone to process effectively. Getting
> this data for other countries is proving difficult to impossible. This means
> that even if you could figure out what street you're on, maybe from
> intercection crossings, there'd be no way of knowing how far along the
> street you are. Also, in an automatic track there's no way to know in
> advance how many points there'll be. If you go over 100 the percentage
> method breaks down. In automatic point naming there'd have to be a method of
> naming points so the user knows they're all related to the same route no
> matter where that route goes. I imagine the point names will be pretty
> generic, probably a number that gets incremented with each point. Nothing
> too complicated since they're just track markers and most of them would
> probably get discarded anyway.
> I think the more important system to get working is the ordered checkpoints.
> Once that's in then adding the automatic tracking probably wouldn't be too
> hard since it would pretty much use the same logic.
> On Tue, 9 Oct 2007, Cearbhall O Meadhra wrote:
>> Dear Sean et al,
>> I have been following this discussion with keen interest. I think some
>> very good ideas are appearing.
>> Ronan and I have put together a method of handling POI names when they
>> occur on the same street. We simply add a percentage value to each
>> point name as it progresses logically by longitude or latitude. A typical
> result would be:
>> "main Street 0%", "main Street 10%", "main Street 20%", etc  up to
>> "main Street 100%",.
>> It is possible that this street is laid out in a circle and so this
>> logical sequence might not be the sequence one would meet while
>> walking from one end of the street to the other. In that case, I would
> recommend that the "%"
>> value be separated from the rest of the point name as a numeric field
>> that could be edited automatically as recommended in the suggestions
>> below, to be rearranged according to the sequence in which they occur to
> the pedestrian.
>> Of course this would mean that the system must know the increments of
>> the percentage values so that the correct ones are maintained but I
>> think that would be easy enough to manage.
>> The value of using the percentage as an incremental identifier is that
>> it allows a universal method that gives a sense of the location of the
>> walker in relation to the beginning and end of the street while giving
>> a unique ID to the point of interest.
>> Any comments?
>> All the best,
>> Cearbhall
>> "Good design enables - Bad design disables"
>> Tel: 01-2864623 Mob: 087 9922227 Em: cearbhall.omeadhra at projectidd.ie
>> -----Original Message-----
>> From: loadstone-bounces at loadstone-gps.com
>> [mailto:loadstone-bounces at loadstone-gps.com] On Behalf Of Dave Mielke
>> Sent: 09 October 2007 03:19
>> To: loadstone at loadstone-gps.com
>> Subject: Re: [Loadstone] Routes and trips.
>> [quoted lines by Shawn Kirkpatrick on 2007/10/08 at 17:01 -0700]
>>> They're a list stored in memory. This avoids having to do any lookups
>>> using the database engine.
>> i believe this is a good thing for features such as these. Here are
>> some
>> suggestions:
>> I see a tracked or recorded trip and a user-defined route as being the
>> same thing except for how the data is entered. In both cases one wants
>> to end up with an ordered list of checkpoints. That's what loadstone
>> already has. To make these features work, therefore, I think there are
>> four features which need to be added.
>> First: Regardless of how the data is entered, both features need the
>> currently loaded checkpoint list to be editable. This means that there
>> needs to be a way to bring up the list of checkpoints, and for each
>> item to have options like rename, move (up or down within the list),
>> delete, "go to" (see second feature) to select the next point, and
>> "explore" (see fourth feature) to find out what's near by. The
>> "explore" function would probably be more useful if it only considered
> unchecked points, i.e. points not on the route.
>> Second: Regardless of how the data is entered, there needs to be a way
>> to activate the currently loaded checkpoint list as a rrute. By
>> default, the next checkpoint to go to would be the first one in the
>> list, although the user could use the "go to" function (see first
>> feature) to tell loadstone where he actually is on the route.
>> Loadstone would only monitor the next checkpoint (the selected item)
>> until the user gets there, at which time it'd to an implicit "go to"
>> to the next item in the list. It could even warn the user if he's moving
> away from the point.
>> Third: Defining a route is probably as simple as adding a point to the
>> end of the currently loaded checkpoint list whenever it's checked.
>> That's probably already the way it's done. A useful enhancement,
>> though, would be the ability to check a point while it's being
>> defined. Adding this to the save point submenu would be convenient.
>> Fourth: For recording a trip it needs to be possible to both
>> automatically and manually add points. Automatic points clearly need
>> to be added each time the user changes direction, but should probably
>> also be added at a regular time interval even if the user doesn't
>> change direction. The name for an automatically added point should
>> begin with the word "auto", and include the time it was added as well
>> as the direction in which the user was moving (the new direction if a
>> change). This information, in conjuction with the "explore"
>> option (see first feature) will help the user later when he goes
>> through the points to give them more meaningful names. A manually
>> added point should have a similar default name except that it should
>> begin with "user" rather than "auto", but should also allow the user
>> to immediately assign a more meaningful name.
>> That's my initial proposal in order to get some discussion going.
>> --
>> Dave Mielke           | 2213 Fox Crescent | I believe that the Bible is
> the
>> Phone: 1-613-726-0014 | Ottawa, Ontario   | Word of God. Please contact me
>> EMail: dave at mielke.cc | Canada  K2A 1H7   | if you're concerned about
> Hell.
>> http://FamilyRadio.com/                   | http://Mielke.cc/bible/
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