Greg, Michael, René, thanks infinite for your hints, i'm not yet able to give you feedback in the form of code :-/ the code is a bit complex "for me" so i'm studing your wonderfull suggestion! right now i'm here http://code.google.com/p/pyeuclid/ i installed the library and i'm doing a "depth" lecture of the site : it's a wonder-complex word, my background don't give me the ability to code it for now. Reading your hints i can see that i can follow different procedure to ontain the same results, i need to strat to study the problem, in theory i've idea on what a quaternion is and its math properties but is a bit hard to undstand how to code to perform a rotation. to learn more maybe i need numerical examples, so now i'm creating 2 first function to : transform lon-lat-heading to quaternion representation and viceversa from quaternion to euler angles. something like : euler2quat(lon,lat,heading) quat2euler(q) # where q = array((x,y,z,w),float) btw, i'll continue to reading and study tring to find a solution to a numerical example, like start: point_0 = 0,0,0 - go ahead for ( 0 degres_X ; 45 degres_Y ) (north direction) stop1 : position = point1 point_1 = 0,45,0 - rotate = 22.5° (NorthNorth East) and go ahead for ( 5 degres_X' ; 5 degres_Y' ) where X' and Y' are new axis " |_ " point_2 = x,y,heading <- unknow * greg : can you point me on example using that ethod ? R should be a rotation matrix and a is an angle in radiants i can create R following notes from : ? Forward-back: R' = Rx(a) * R Left-right: R' = Ry(a) * R Change heading: R' = Rz(a) * R and then after compute the new R' i need to convert to euler using : ? (but this method shoul'd be valid for point =! pole) make sense what i wrote ? thanks a billion to help me!!! Ciao, Massimo. |