Animation glitch - order of animations in tree affecting result??

Started by DriesV, July 02, 2013, 01:35:50 AM

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DriesV

I just encountered a glitch in KeyShot Animation.

See attached bip files as reference.
I have applied 2 rotation animations to the top part. The idea is to rotate it to the right (using the bottom part as pivot reference) and to keep it upright.
It seems that the final result is determined by the order of animations in the scene tree...

animation-glitch.bip has the correct solution.
animation-glitch2.bip has the wrong solution.

You can see that if the 'ROTATE ball - to right' rotation animation is put on top of the other, the result is not correct.

1st image: initial situation
2nd image: correct result (animation-glitch.bip)
3rd image: wrong result (animation-glitch2.bip)

I can still get it right by carefully checking the order of animations, but this makes for a very cumbersome and confusing process. :-\ Also it is not clear to me why different ordering should lead to different results...
Glitch or not? That's the question. :)

Dries


DriesV

Quote from: Thomas Teger on July 02, 2013, 07:10:21 AM
We will look into it.

Thanks, Thomas!

Any chance for a quick fix? ;)
I'll have to use a lot of these animations for my Toon Challenge entry. :D

Dries

guest84672


DriesV

Ah, Thanks for the feedback! ;)

At least now I can change my model and animation plan beforehand. I would have gone mad if I found myself cornered in an impossible situation close to the deadline.

Dries

DriesV

Quote from: Thomas Teger on July 03, 2013, 06:33:06 AM
Bug is confirmed, but no quick fix ... :-(

Thomas, can this bug be pinned down to this situation?

  • A rotation animation with a helper object (other than 'self') as pivot point
+
  • A second rotation animation applied to the same part/group with 'self' as pivot point
Dries

DriesV

I think if I animate the avatar according to attached example, I should be safe.

Dries

KeyShot

Hi Dries,

The issue in the scene is that the self rotation rotates around the object itself. The pivot point in this case will always be the original location. That means if you move the object using the rotate to right animation then you will be moving the object away from its original pivot point thereby causing the keep up rotation to behave differently. The solution to this is dynamic pivot points that move with the object and this is something we are going to add soon. I hope this is not too confusing.

-- Henrik

DriesV

Quote from: KeyShot on July 10, 2013, 02:29:41 AM
Hi Dries,

The issue in the scene is that the self rotation rotates around the object itself. The pivot point in this case will always be the original location. That means if you move the object using the rotate to right animation then you will be moving the object away from its original pivot point thereby causing the keep up rotation to behave differently. The solution to this is dynamic pivot points that move with the object and this is something we are going to add soon. I hope this is not too confusing.

-- Henrik

I think I get it. ;)

Dynamic pivot points sound like a big improvement. It will eliminate a lot of unpleasant surprises on more complex animation sequences.
Also, I was unaware that the pivot point for 'self' rotations always remained at the original location. I simply assumed it would move along with the object itself...

Dries