That's what I thought, but giving it a keyframe at frame zero gave me unwanted roll along the path. I probably could fix it by keyframing the roll. I just am trying to understand it better. ᐧ
On Thu, Jan 2, 2014 at 3:51 PM, Eric Thivierge <[email protected]>wrote: > Objects evaluate keyframes, then constraints so the keyframe should reset > the orientation then the constraint will kick in and reevaluate the > orientation for you. > > > On Thursday, January 02, 2014 3:49:29 PM, Alan Fregtman wrote: > >> Because you didn't keyframe it? >> >> Kinematics evaluate per frame and if you jump around too violently in >> your timeline you're gonna get inaccuracies unless you lock things >> down a bit by using keys or strict upvectoring. Keys give it a >> starting point from onto which to evaluate the constraints on. >> >> >> >> On Thu, Jan 2, 2014 at 3:33 PM, Paul Griswold >> <[email protected] >> <mailto:[email protected]>> wrote: >> >> Yes and no. I guess more than anything I don't understand why, if >> an object has a 0,0,0 rotation on frame 0, but path constrained. >> Why when you jump from a frame back to frame 0 does it inherit >> whatever rotation it had rather than return to 0,0,0? >> ᐧ >> >> >> On Thu, Jan 2, 2014 at 2:28 PM, Ponthieux, Joseph G. >> (LARC-E1A)[LITES] <[email protected] >> <mailto:[email protected]>> wrote: >> >> Create a path(curve).____ >> >> __ __ >> >> Create a null.____ >> >> __ __ >> >> >> Path animate the null to the path, set it to tangent and set >> the up vector.____ >> >> __ __ >> >> >> Duplicate the null making it null1. Turn tangent off, reset >> the orientation to zero.____ >> >> __ __ >> >> >> Create a third null, position constrain it to follow the first >> null. Second is identical in position so ignore it.____ >> >> __ __ >> >> Constrain the third nulls orientation to the first null.____ >> >> __ __ >> >> >> Constrain the third nulls orientation to the second null. Open >> the top orientation constraint of the third null and adjust >> the blend weight. You may need to use a rotation >> offset(probably 180 in Y) to get the appropriate blend.____ >> >> __ __ >> >> >> Use the blend weight to blend from the first null to the >> second null orientation, keying it to adhere to the tangent >> null as needed.____ >> >> __ __ >> >> Constrain the object you want animated to the third null. ____ >> >> __ __ >> >> Is that what you want?____ >> >> __ __ >> >> --____ >> >> Joey Ponthieux____ >> >> LaRC Information Technology Enhanced Services (LITES)____ >> >> Mymic Technical Services____ >> >> NASA Langley Research Center____ >> >> ______________________________________________________ >> >> >> Opinions stated here-in are strictly those of the author and >> do not ____ >> >> represent the opinions of NASA or any other party.____ >> >> __ __ >> >> *From:*[email protected] >> <mailto:[email protected]> >> [mailto:[email protected] >> <mailto:[email protected]>] *On Behalf >> Of *Paul Griswold >> *Sent:* Thursday, January 02, 2014 2:02 PM >> *To:* [email protected] >> <mailto:[email protected]> >> *Subject:* path constrain Q (duh moment)____ >> >> __ __ >> >> >> When you path constrain an object & have it point along the >> path as well as maintain tangency, how do you get it to reset >> it's rotations back to 0,0,0 when you scrub back to frame 1?____ >> >> __ __ >> >> >> Setting a key causes unwanted rotations & setting a neutral >> pose doesn't seem to work.____ >> >> __ __ >> >> I know this is a face-palm moment....____ >> >> __ __ >> >> -Paul____ >> >> __ __ >> >> ᐧ____ >> >> >> >> >
