topic Re: animation / path constraint / object direction change in 3ds Max Animation and Rigging Forum

animation / path constraint / object direction change

Anonymous — Tue, 14 Sep 2021 10:29:19 GMT

Hi there!

I've a question related to path constraints.

I have an object moving along a path and at one point it needs to keep its previous rotated direction, but continue to move in -X direction (if I'm explaining this right).

Kind of like a car thats driving along a street and then curving on the street 90° to back off backwards into a car lot.

To simplify my issue I've just used a simple cone.

So theres one point where the path is just turning straight the other direction by 360° where I need to tell max that it should keep the objects prior direction and just move -X. Kind of saying it to not 'follow' the path direction anymore - but I need it to follow the path generall, just by -360°?

Thanks for help!

Re: animation / path constraint / object direction change

domo.spaji — Tue, 14 Sep 2021 15:21:21 GMT

You could add rotation key +/- 180 (not 360), on "turning" frame, setting its tangents to "stepped", to manage that ...

But you wouldn't get realistic motion just by doing that... Vehicle should slow down, stop for a moment before start moving reverse...

Re: animation / path constraint / object direction change

Anonymous — Tue, 14 Sep 2021 20:25:23 GMT

Thanks for your answer, I actually did that and kinda worked, but it was
not 100%satisfying / clean to my mind.

I also ran into the issue that I had to deal with another similar situation
later on the same spline but when it was moving down in - z direction.
When my object moved down at that later stage it rotated in twice
direction... X and z although the spline was going straight down.

So the second turn was 90 degree but downwards. Just straight.

So what I'm animating there is a tie fighter parking in a car parking lot..

I feel there must be a cleaner way and an easier to manage way then to set
key frames before and after the turn and then rotate the turning frames by
x degree?

What I also tried was to just animate the tie till the turn through the
spline and from there continue the animation without the spline constraint,
but.. With the constraint attached I can only move it along the path.

Re: animation / path constraint / object direction change

leeminardi — Tue, 14 Sep 2021 20:37:31 GMT

Consider linking the tie fighter to a dummy that has the path constraint. This should give you the freedom to rotate the fighter to any orientation yet still maintain the path constraint. The "follow" options, if checked, sets the roll angle which may not be what you want. Linking the fighter to a dummy will give you full control of roll, pitch, and yaw independent of the spline's transverse vectors.

Re: animation / path constraint / object direction change

Anonymous — Tue, 14 Sep 2021 20:51:22 GMT

Another idea..

Is there a way to key frame the end position and rotation of the path constraint animation?

So that I can continue with a clean secondary animation from the same point?

Re: animation / path constraint / object direction change

Anonymous — Tue, 14 Sep 2021 20:56:54 GMT

Your saying to animate a dummy object instead and then link it to the tie once the dummy is properly animated?

And not use the follow function at all. I liked that for the bigger flying part actually alot, along with banking but it also has it flaws for sure...

So you think it's just better to literally control every single motion yourself? No follow, no banking.

Re: animation / path constraint / object direction change

domo.spaji — Tue, 14 Sep 2021 23:40:53 GMT

And to @Anonymous...

You don't have to do any linking for that.

You already have freedom to rotate to any orientation (and maintain the path constraint).

Path constraint is a position controller, although have rotation elements.

But if you won't to get back pos. controller (Pos.XYZ or any) you don't have to do any linking for neither...

You could simply add it to the "list"

If you assign Path Constraint thru the Animation menu (as you did), it is already layered in the "Position List"

Everything is easier and faster when working with layers.

Only thing is one should get little bit more knowledge in animation