Page 1 of 1

Problems with Animation

PostPosted: Sat Jul 12, 2008 6:05 am
by GPNMilano
Okay, I'm stumped so I'm passing this one off to others for help.

I have an object, that I want to rotate 360 degrees on its Z axis, with a duration of 9 seconds. This animation starts upon link in, and loops indefinitely. Seems simple enough. The new plug-in automatically defaults to those settings so no Alcscripting is involved. So, I start with the first frame, and set it to "I" then choose the "rot" option in blender. Go to the 270th frame. Rotate the object 360 degrees, repeat. And my animation is complete.

I link in, the object is stationary. I check my blend file, the object doesn't rotate at all during the animation, the curve is flat. I fiddle around with it. I decide to rotate it 180 degrees from the 1st to the 135 frame. And then the rest of the rotation for the 136-270th. This doesn't work either. Instead it just rotates one way for half the rotation, then reverses itself and goes the back to the starting position, rather than rotate completely 360 degrees.

So now, my question is what the heck am I doing wrong. I tried rotating it -180 degrees, that didn't work. the curve just resets itself to the original position and the animation looks like it makes a half turn, then comes back around.

Re: Problems with Animation

PostPosted: Sat Jul 12, 2008 6:26 am
by Jojon
Looks like Blender always picks the shortest route... :7

Opening an IPO editor window and setting the point manually to 36 (yes 36, not 360 or 2PI or something like that, go figure) seems to do it (the transform properties window helps).

Re: Problems with Animation

PostPosted: Sat Jul 12, 2008 10:59 am
by agrif
Moving the point manually is the cleanest option, but you could also rotate it in 90 degree steps. The shortest route in this case would be the correct route. It just depends on which is easiest to do at the time.

Re: Problems with Animation

PostPosted: Sat Jul 12, 2008 11:09 am
by GPNMilano
I tried the 90 step Agrif, it didn't work unfortunately. The last step just reversed completely in the opposite direction that the first 3 were moving in.

EDIT: Nevermind. Agrif was right about the 90 step thing. I missed a step somewhere in the 90 increments, and it went back to its original position for some reason. Now it works. Phew.

Re: Problems with Animation

PostPosted: Sun Jul 13, 2008 10:49 pm
by Nadnerb
You can do this in two keyframes, it's just that you're running into one of blender's "helpful assumptions" :P in it's editing interface. When you select an object and "r" rotate it 360 degrees, it says "oh, 360 degrees, you're starting right where you're ending, so I won't change the rotation at all." :P The multiple step method gets around this because you're not starting from 0 degrees so the starting rotation isn't the same as the ending rotation.

You can get around this in a more elegant way by pressing "n" to bring up the transform properties and manually entering 360 in the z rotation box. That way it will stick. (I really suggest you do it this way, it's better ;))