Since I am doing this all server side with no need to draw a map, I'm using perl and some modules obtained from CPAN. Specifically, I'm using Google::Directions. It turns out that the module had an error in the Polyline.pm module. For some reason it was decoding the polyline as a series of offsets from the last point instead of just decoding the values as the lat and lons. I modified the module so it now decodes the lat/lon pairs correctly and all is well. Thanks.
Cameron On Wed, May 23, 2012 at 9:06 AM, geocode...@gmail.com <geocode...@gmail.com>wrote: > On May 23, 6:40 am, Cameron Crum <cameron.c...@gmail.com> wrote: > > Steps. > > Does your map get different results from mine? > > > > > On Wed, May 23, 2012 at 8:20 AM, geocode...@gmail.com > > <geocode...@gmail.com>wrote: > > > > > > > > > > > > > > > > > On May 22, 10:49 pm, ccrum <cameron.c...@gmail.com> wrote: > > > > I recently noticed that the polyline returned in each step in a route > > > > does not always start and end with the coordinates the step says it > > > > does. For Instance, I ran a directions query from Fort Worth, TX to > > > > Austin, TX. The start and end points returned were: > > > > > > 32.72468 -97.32085 and 32.04823 -97.09488 > > > > and it's html was "Take the ramp on the <b>left</b> onto <b>I-35W S</ > > > > b>" > > > > > A link to a map would be better. > > > > > I get this: > > > > >http://www.geocodezip.com/v3_GoogleEx_directions-draggable2Xml.html?a. > .. > > > > > The first point of the polyline returned for me is: > > > <point lat='32.725410' lng='-97.320840' /> > > > > > > The start point of the polyline was indeed 32.72468 -97.32085 but the > > > > last point of the polyline was 32.48797,-97.54039. > > > > > The last point of the polyline I get is: > > > <point lat='30.267100' lng='-97.743080' /> > > > > > > The polyline also > > > > contained 603 points. This is a dramatic difference in location > > > > between what the path reports and the polyline shows. Furthermore, > > > > Step 3 started with the declared end point of Step 2 (32.04823 > > > > -97.09488) and continued on. There were breaks like this in other > > > > steps as well. Step 3 had the following start and end coordinates > > > > listed in the step: > > > > > > 32.04823 -97.09488 and 31.04757 -97.46572 > > > > > > and once again the Step 3 polyline started with the same coordinates > > > > (32.04823 -97.09488), but ended dramatically different with > > > > 31.21956,-97.61789 as the last point of the polyline. Step 4 was also > > > > off, but steps 5,6,7, and 8 had matching step coordinates and > polyline > > > > start and end coordinates. The latter steps were also much shorter > > > > containing only a few sets of coordinates whil3 2,3 and 4 had several > > > > hundred coordinates each. > > > > > > So, does anyone have any idea why this is happening? If I try to > plot > > > > the lines on a map abased on the polyline coordinates, I get several > > > > disjointed lines and they are definitely not the route from Fort > Worth > > > > to Austin unless Google is assuming we can teleport along the path. I > > > > need the actual polylines as I am trying to determine total miles > > > > traveled per state and can do an intersect query in SQL spatial > > > > against a set of state polygons to determine which step subsections > > > > are in which states. If the polylines "wander" like this, I won't be > > > > able to use them. > > > > > What polyline are you looking at? The simplified summary polyline > > > (overview_path) or the polylines in the steps (path)? > > > > > -- Larry > > > > > > Regards, > > > > > > Cameron > > > > > -- > > > You received this message because you are subscribed to the Google > Groups > > > "Google Maps JavaScript API v3" group. > > > To post to this group, send email to > > > google-maps-js-api-v3@googlegroups.com. > > > To unsubscribe from this group, send email to > > > google-maps-js-api-v3+unsubscr...@googlegroups.com. > > > For more options, visit this group at > > >http://groups.google.com/group/google-maps-js-api-v3?hl=en. > > -- > You received this message because you are subscribed to the Google Groups > "Google Maps JavaScript API v3" group. > To post to this group, send email to > google-maps-js-api-v3@googlegroups.com. > To unsubscribe from this group, send email to > google-maps-js-api-v3+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/google-maps-js-api-v3?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Google Maps JavaScript API v3" group. To post to this group, send email to google-maps-js-api-v3@googlegroups.com. To unsubscribe from this group, send email to google-maps-js-api-v3+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-maps-js-api-v3?hl=en.
