Edit: Thread title should read: “… is Changed or File is Saved”
Note: I can’t upload the test blend as I originally planned because the problem outlined below also occurs if the file is saved (even without translating the second monkey).
Two monkeys falling onto a plane.
The first is a simple rigid body (active).
The second is also active, but has its “animated” property keyframed ON for the first two frames, then keyframed OFF in the third frame. In frame 1, a rotation keyframe is assigned. In frame 2, the monkey is rotated slightly around the z axis and another rotation keyframe is assigned.
This is the procedure used at the very start of blendercookie’s tutorial where a number of buttons fall down spinning to form an image of their mascot (http://youtu.be/iYL9w6xsZ6g)
If I could attach a working blend file, and if you loaded it and immediately pressed Alt-A to run the animation, you would see the first monkey fall down with no rotation, and the second monkey fall while rotating during the entire fall. So far so good.
BUT, just grab the second monkey and translate it up on the z axis a small amount. Hit Alt-A, and this time the second monkey rotates only between frame 1 and 2 and then falls down with no further rotation. I’ve checked the keyframing, and they all seems OK.
The problem also happens if the file is saved without translating the second monkey upward.
Any ideas why the simple translation or file save seems to mess this up? Thanks!
Note: This file demonstrates the result of the problem. I can’t upload a working one since saving the file creates the problem.
Impart Initial Rotation to Falling Object 01.blend (569 KB)