[Accessibility] Finding the Nearest POI

[Alex Jurgensen]

Hi,

Thank you for the useful information. My trouble is that I don't know how to search for the nearest POIs in all the dirrections. This is where the root of my problem stems from. I understand how to calculate the projection, or at least some of the theory behind it, but I am stubling on how to do this search of POIs.

Any help is appreciated.

Regards,
Alex,


Alex Jurgensen,
AWEBSIGHT Administrator,
ICE Customer Care,
VoiceOver Trainer,
ASquared21 at visionmail.uni.cc			

Visit us on the web at: http://www.visionmail.uni.cc/

On 2009-11-16, at 1:56 AM, Lulu-Ann at gmx.de wrote:

> Hi Alex,
> 
>> Let me try to explain it. I am standing near the intersection that Trekker
>> calls 57 Avenueand 180 Street. I want my application, at the clickof a
>> utton, to tell me this intersection is the nearest. My problem comes from the
>> fact that I can't figure out howto identify the nearest POI from within my
>> application.
> 
> 
> You get the coordinates from your GPS.
> You know the coordinates of some nearby POIs or intersections.
> 
> For a first guess
> I would search for the 4 points that are nearest in each direction (That is an easy linear comparison with the two coordinates.
> Then calculate the correct distance (you will need to find the formula for the projection)
> Wikipedia might help you to start: http://en.wikipedia.org/wiki/Geographic_coordinate_system
> and
> http://en.wikipedia.org/wiki/World_Geodetic_System
> 
> And last, pick the one of the four that is nearest...
> 
> Hope this helps you.
> 
> Regards
> Lulu-Ann
> -- 
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