Formula for getting longitude
I'm implementing a simulation in Java using a GIS (WGS84). I want to place my agents shifted to each other. The latitude is easy 1 m is 1/111000 degrees. But I want to shift an agent on the longitude side I have to consider earth curvature (I guess!). 
I found this formula on Wiki: a= (2*pi*r*cos(phi))/360
r: radius
phi: latitude
a: should be the distance

I tried now multiply my distances to 1/a, but the positions are not logical!

I would appreciate any suggestion! Thanks in advance!

Yussef  

Formula for getting longitude
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I'm implementing a simulation in Java using a GIS (WGS84). I want to place my agents shifted to each other. The latitude is easy 1 m is 1/111000 degrees. But I want to shift an agent on the longitude side I have to consider earth curvature (I guess!). 
I found this formula on Wiki: a= (2*pi*r*cos(phi))/360
r: radius
phi: latitude
a: should be the distance

I tried now multiply my distances to 1/a, but the positions are not logical!

I would appreciate any suggestion! Thanks in advance!

Yussef  
