Hey,

I have some issues with mapping converted coordinates to a sphere. I'm using libnoiseforjava and the jMonkeyEngine.

First my conversion methode:

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| public Vector2f cartesianToGeo(Vector3f position, float sphereRadius) { sphereRadius = FastMath.sqrt((position.x*position.x)+(position.y*position.y)+(position.z*position.z)); float lat = (float)Math.asin(position.z / sphereRadius) * FastMath.RAD_TO_DEG; float lon = (float)Math.atan2(position.y, position.x) * FastMath.RAD_TO_DEG;
return new Vector2f(lat, lon); } |

This is the mapping method from libnoiseforjava:

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| public double getValue (double lat, double lon) { assert (module != null);
double x, y, z; double r = Math.cos(Math.toRadians(lat)); x = r * Math.cos (Math.toRadians(lon)); y = Math.sin (Math.toRadians(lat)); z = r * Math.sin (Math.toRadians(lon)); return module.getValue (x, y, z); } |

And here is what I get (using sphere approximation from octahedron):

It looks like two spheres into one another and on the right is the transition between them with a high count of points. My assumption is, that the getValue method expects latitude and longitude in an area from -90 to 90 degrees. My conversion method only returns values from -180 to 180 degrees. That's probably the reason why I get two spheres. First: does anybody agree? Or is there another mistake? Second: Is there an easy way to also convert the new geo coordinates to an area from -90 to 90 degrees. Or a better method that gives values in this area from the beginning? My math skills kinda suck

Greetings

JCollie