[Bf-funboard] Re: playing ball with constraints

Anthony Zierhut bf-funboard@blender.org
Wed, 9 Jul 2003 11:52:32 -0700 (PDT)

Yes! Thanks Chris.  This is how I used to do it and it
works.  I called it the "Texas switch" - a term used
in special effects for fooling the camera with slight
of hand.  It only gets messy when animation needs to
be changed and the ball can appear to "pop" around if
the hidden-layer ball isn't carefully repositioned
after the change.  But the current COPY LOCATION
constraint works beautifully.  I used it yesterday to
show a character breaking an object in two and
throwing the pieces at the camera.  *The only hitch
was finding the rather (in my humble opinion) esoteric
Blender command for putting a keyframe in the
constraint IPO: click on the word "Inf" in the upper
right, turning it white, then ctrl + LMB on the IPO
graph where the frame number and influence level
converge.  (It took a bit of hunting to find this
out.)  But the object animated as completely solid
until the moment it snapped in two when the influence
IPO was pulled to 0 in one frame and the two pieces
came apart.  Beautiful.


> Call me *really* old fashioned, but I would have 3
> copies
> of the ball (one parented to each guys' hand, and a
> third
> one that is 'free'). As the ball is released from a
> character's
> hand the ball in his hand jumps to an invisible
> layer, and
> the free ball jumps from an invisible layer to a
> visible
> layer. The free ball travels to character #2, and as
> it
> reaches his hand it jumps to an invisible layer, and
> the
> ball that is paranted to character #2's hand jumps
> from an
> invisible layer to a visible one. The cycle
> continues ...
> It's not pretty, but it's easy to set up with layer
> keys
> instead of constraints.
> Chris