[Bf-committers] Animation project

[Stephane SOPPERA]

> Second, SHIFT-S -> Horizontal put ALL keys horizontal. Have a look at:
> http://perso.wanadoo.fr/stephane.soppera/blender/capture5_.png
> http://perso.wanadoo.fr/stephane.soppera/blender/capture6_.png
> you'll notice that the fourth key is not horizontal.

Have also a look at the script to understand the computation.
What the script does is:
- keep the IPO continuous (handles from each side of a point on the same 
line)
- prevent any overrun of values. The values of the interpolation between 
two point are limited by the value of these two points and never go over 
or beyond them.
That has for consequence that if two keys have the same values, their 
handles will be horizontal.
That has also for consequence that is a keys is a local minimum or 
maximum, its handles will be horizontal.
But if a key has a previous key with a greater value and a next key with 
a lower value (or the contrary), an acceptable slope will be computed to 
fulfill the two conditions (continuity and don't overrun).

-- 
Stephane SOPPERA
http://perso.wanadoo.fr/stephane.soppera