Point on the surface of a sphere

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DJWoodgate

Hi Siread, I tried that formula and it only works for locations on or near the prime meridian.

I think it should be something like this if your globe is oriented normally with North pointing up the Y axis.

latitude# = -53.10		;Wembley
longitude# = 0.07

theta#=90+latitude : phi#=180+longitude

z# = Sin(theta) * Cos(-phi)
x# = Sin(theta) * Sin(-phi)
y# = Cos(theta)

This is based on the formula given here http://local.wasp.uwa.edu.au/~pbourke/texture_colour/spheremap/
adjusted slightly for the way the axis are oriented in blitz.