View Full Version : Motion Baker

08-20-2007, 08:30 AM
I am involved with creating dice that tumble in a realistic way, sort of like a craps game. You throw the die and they tumble against a wall and bounce back. For realism I used HardFX dynamic and set up collision walls. All was well. The client then wanted the dice to end up with one spot, on one face, filling the frame. Two more animations required the dice to fall away from this one spot, rotate and bounce and come back to a spot on another face of the dice. This was extremely difficult to arrange using HardFX alone. I thought that if I could use motion baker I could then "take over" the simulation and key-frame the animation from there on. Motion Baker, though, does not seem to work with dynamics. I did the job by studying the HardFX simulation and then creating an animation that did the trick. I am sure some of you would have a much better solution than this! I would be very greatful for any comments regarding this.

08-20-2007, 10:09 AM
Why not just use the Editfx tools built into HardFX? It allows you to do just that (physically change the simulation and keyframe the postiions and rotations of the dice yourself).

08-21-2007, 05:52 AM
Thanks for the tip Larry. I will try that and get back to you.

08-21-2007, 06:33 AM
I just consulted the manual for the edit FX tab. I was trying to edit a curve by specifying fix frames (15 to 46) and i wanted to pull up the top of the curve from frame 30, the result was that it did not reshape the motion curve in the way I expected but pulled up in the Y axis the whole of the curve. If I choose "current frame" then i can pull up just that frame, creating a spike in the curve. I can create a curve though as a kind of null it seems. It would take me ages using this tool but I guess I have still a lot to learn. Any ideas for books I should be reading?

08-21-2007, 08:17 AM
Select edit start on say frame 30 and edit end on frame 60. If you go to frame 50 and move it using the editfx tool youll get a nice interpolated curve on that piece from frame 30 to frame 60. Editframe should be set to all.
When I do a test it does give me a nice smooth curve.

08-24-2007, 02:01 AM
Hi Larry
Yep! that did it. Thanks for the info. I also changed the camera to perspective and added realistic motion blur. Then I noticed that the render slowed right down when my laptop went to sleep. When I looked at the frame times, there was a considerable gap at that point. That was easily remedied though - no sleeping on the job. I turned off all memory saving stuff and all was well.