Jim Wilson wrote: > Is there a simgear or plib function that I can use to get the angle > between two locations?
I doubt there's explicit API support anywhere, but it's pretty easy to do by hand. Just exploit the fact that the dot product of two unit vectors is the cosine of the angle between them: // Needless to say, from memory and untested! sgNormalizeVec3(v1); sgNormalizeVec3(v2); float angle = arccos(sgScalarProductVec3(v1, v2)); The eager optimizer (Norman :) might note that you could shave a few cycles here by doing the dot product first, and then doing the scaling together to eliminate a division an a sqrt. Andy -- Andrew J. Ross NextBus Information Systems Senior Software Engineer Emeryville, CA [EMAIL PROTECTED] http://www.nextbus.com "Men go crazy in conflagrations. They only get better one by one." - Sting (misquoted) _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
