[Algorithms] Splines as keyframes

[Jason D. <jas...@bl...>]

Given a number of 3D coordinates, I want to generate a catmull-rom spline
connecting them - This is easy.

Using those same points as regularly spaced position keys on a timeline, you
can use the sampled positions on the curve as the resulting tweens.  How do
you handle proper acceleration and deceleration if the keys are not at
regular intervals?

For example, I have a key on frame 1, frame 30, and frame 40.  All three are
30 units apart in X.  The interpolation will generate 30 tweens from frame 1
to 30, 1 unit apart, and 10 tweens between 30 and 40, 3 units apart.  I
assume you have to interpolate the frame times as a spline as well, but
can't wrap my head around it.

Suggestions?


Jason Dorie
Black Box Games
(604) 818-5330 (direct)
Jason.Dorie@BlackBoxGames.com