Jump to content
Sign in to follow this  
ahschmidt

AE question: Rotation vs Orientation

Recommended Posts

When you are using 3d in AE, what is the difference between orientation and rotation? Is there a standard about which to use?

 

from After Effects Help:

"You can turn a 3D layer by changing its Orientation or Rotation values. In both cases, the layer turns around its anchor point. The Orientation and Rotation properties differ in how the layer moves when you animate them.

 

When you animate the Orientation property of a 3D layer, the layer turns as directly as possible to reach the specified orientation. When you animate any of the X, Y, or Z Rotation properties, the layer rotates along each individual axis according to the individual property values. In other words, Orientation values specify an angular destination, whereas Rotation values specify an angular route. Animate Rotation properties to make a layer turn multiple times.

 

Animating the Orientation property is often better for natural, smooth motion, whereas animating the Rotation properties provides more precise control."

 

There's even a movie linked to from that page that shows the difference.

Share this post


Link to post
Share on other sites

I have to say that I hate the fact that AE decided to solves the Euler/Quaternion problem in this manner... simultaneously.

If they didn't I would already have an awesome plugin from Rick Barrett that pulls AE data into C4D automatically, with a single click.

(Shit, did I just say that out loud? ;) )

 

I do undertand the math problems involved, but I've been animating for years purely with Euler coordinates (and a few hacks).

Do Quaternions really matter for shit with anybody in the AE world? I'm dying to know.

 

Please... even if you're just a lurker, speak out loud about your usage as an artist regarding AE's Rotation vs. Orientation and when you use which.

There are many people here who could benefit from this knowledge.

 

Thanks a bunch. :)

 

-m

Edited by the_Monkey

Share this post


Link to post
Share on other sites

Please... even if you're just a lurker, speak out loud about your usage as an artist regarding AE's Rotation vs. Orientation and when you use which.

There are many people here who could benefit from this knowledge.

 

Thanks a bunch. :)

 

-m

 

I wasn't even aware that there was a technical difference. I have no idea why there are two ways to rotate objects in AE. I try to make sure I use one or the other exclusively so I don't get any nasty surprises, but that's about it. Oh, and while I'm on the subject, I still don't understand the point in Point of Interest on the AE cam. :P

 

That is all.

 

Dan

Share this post


Link to post
Share on other sites

Euler: Pronounced "oiler" Euler is a common method for calculating 3d rotations. Is popular because it uses 3 values X, Y Z angles. Euler requires a "rotation order" and can experience gimbal problems, the worst resulting in Gimbal Lock when 2 axes align. this is why it's sometimes refered to as Gimbal, instead of Euler.

 

Quaternion: Method of rotation that uses four values, xyz and t. XYZ are position values used to calculate a vector direction, and t is a roll value.

 

Gimbal: Gimbal is the effect caused when Euler rotation axes break the usual 90 degree angle difference on a rotation manipulator. The extreme of this is gimbal lock when two axes align completely

 

(from http://www.guerrillacg.org/home/3d-rigging/the-rotation-problem)

 

 

Share this post


Link to post
Share on other sites

I dunno, I always thought the purpose of orientation was to set the initial angle from which to rotate from. That way, you are much less likely to have gimbal problems. If you want a layer to swing on the Y-axis, but you want the Y-axis to be tilted, you tilt it in orientation, so things don't get all screwy gimbal-wise.

 

The biggest problem I have with orientation and rotation is when it comes to parenting. If you rotate a layer in 3D space and then parent another layer to it, the child layer's rotation often goes all screwy. I hate that. Especially because in C4D I often position objects around a globe by parenting the object to a null and rotating the null. If you try to do anything like that in After effects, the objects' rotations often flip out.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

×
×
  • Create New...