For some one that wants or needs to have a character walking follow along a path in MotionBuilder as my friend Kiel Figgins shows in Maya http://www.3dfiggins.com/tuts/MoPath/.
There are a few times where this could be very helpful for background characters or when trying to deal with uneven ground and should give you an idea on how to approach controlling the character with a story clip and cycle. Make sure to read over Kiels tutorial to understand the details.
*note the video has no audio, showing proof of concept and the relation constraint settings at the end.
LINK:Video.swf of the Path Animation examle
In the video is an example of hooking up an FK skeleton on to a path and having it follow along a curved path.
Download : Sample File for MotionBuilder
If the Path and Story are giving you trouble or you find you don't need a complex solution, here are a few other ideas and tricks on how to control motion direction over and around surfaces.
1. Chop the cycled clip in to chunks and rotate each chunk and blend between them so the character walks around the corners, each clip controlling over all direction and Blend.
- For a cleaner edit Animate a Turn/lean move, make one clip, mirror the motion, make another clip and use that to blend between the walk cycle clips much like a game would.
2. Bring it out of story in to the take. First cycle the clip and then bake it to the fk skeleton in the current take. Then you could constrain just the forward direction of the hips to the path
- You could also plot/bake it to a control rig, cycle the character in place (button on the character controls) and plot/bake, now you have a FK skeleton walking in place that you can map to a path node .You can also use the time warp in Fcurve to help adjust speed of the walk along the path based on stride length.
- Leaving it on the control rig (if you want to use IK you will have to make a custom hiearchy with the control rig (shown in the DVD) and adjust reach settings to allow for the rig to follow the path. Doing this you might be able to use the foot L and R floor objects and animate them along a path or just key them so that the ankles and feet match the angle of ground the character is walking up.
3. Like example 2, plot to the scene, on the control rig or fk skeleton , with out the path and use the “move keys” tool and regular manipulation of the character to rotate the animation in the direction you want, select the key frames from the turn forward and hit. “move keys” you can do this for each turn. If you do this on the control rig you can adjust the feet ctrls easier to help with the turn transitions.
All that said creating or capturing the correct move list you need is the best solution, while not always possible.
Shortcuts always look like shortcuts, to many of the same walk cycle, to much walk down spline, turning with out taking the “turn” in to account in the motion, auto walks, etc.. all just end up when left as is, producing “computer movement’, so be aware of it and you will be fine:)