AR app using GPS data

Hello all!

I’m trying to create an AR app which use GPS and some external data. It’s similar to existent ones like Nokia City Lens or Wikitude World Browser. So it’s without any markers (as I understand).

I tried search any tips here but unsuccessfully.

Nokia City Lens example: Nokia City Lens in New York City | Pocketnow - YouTube

Wikitude World Browser example: WSA-m 2010: Wikitude World Browser - YouTube

What I need to know how to draw some specific marker(like a small pic+description) on the screen according to it’s and mine GPS coordinates.

The target’s GPS coordinates are provided by some external source via WiFi (also how to do that?).

All help is welcome (especially the code examples)!

Since you use GPS data, I’m assuming it’s a mobile app. As you can predict user location values through multiple ways (Using actual GPS data and using network data like mobile or WiFi but with different accuracy), You can use the lat-long coordinates to find the azimuth of target location and use that to find where is it, with respect to your user location.

Now I’m looking how to draw a marker of the target on my compass bar (done with gui.label).

I have 2 GPS coordinates (first of my target and the second of my own).

Also I’ve found the following topic :

and I have a couple of questions:

var azimuth : float =
Mathf.Atan2(direction.x,

• why this line has this

?

1. As I understand I need to calculate these latitude-longitute coordinates like this (to calculate the bearing):

Bearing from point A to B, can be calculated as,

β = atan2(X,Y),

where, X and Y are two quantities and can be calculated as:

X = cos θb * sin ∆L

Y = cos θa * sin θb – sin θa * cos θb * cos ∆L
‘L’ be the longitude,
‘θ’ be latitude,

How to choose which point will be “a” and “b” for the formula above?

I’ve took this formula from Formula to Find Bearing or Heading angle between two points: Latitude Longitude -

There is an example there which could clarify what I mean in 2nd question