i just did some quick research and quaternions come up everywhere. maybe someone can shed some light on it. i’ll solve this myself but maybe there is a module already ?
there is a simpler version of it in the ( vvvv user map ) girlpower patch. go into the Interaction.v4p, there its the part with the vector/euler/framedelay/rotate nodes. its just x/y rotation in world space, which i find sufficient in almost all cases.
i haven’t seen the exact arc ball you mentioned around…
cheers boys, i’ve seen the vvvv user map and for me its not good enough. i want the more natural interaction when point on sphere always matches the touch/mouse point. and to make it more tricky, this should also work when the sphere is not centered.