Conversions
Spherical to cartesian coordinates
The formula that you want to use depends on the target coordinate system and the orientation you choose for the sphere. To get an earth-like orientation with poles along the Y-axis in Houdini's right-handed coordinate system:
vector sphericalToCartesian(float lon, lat, rad) { return rad * set( -cos(lat) * cos(lon), sin(lat), cos(lat) * sin(lon) ); }
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