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[edit] 2.40 Release

[edit] change extrapolation type of ipo curves of actions

 added changing the extending / extrapolation type of the IPO curves of
 selected actions in the action editor

  Pose-constraint Ipos now are integrated in NLA

[edit] Autohandles clamping in IPO Window

 Autohandles in Ipo Window still could overshoot. Added a new clamping to
 ensure the handles never result in a curve that goes beyond the neighbour
 control points.
 
 http://www.blender.org/cms/Animation_Curve_Handle.717.0.html

 Ipocurves with "Auto" handles now have option to remain horizontal on the
 extrema (tops & valleys). Use ALT+H to set this per selected curve.
 Note this is a per-curve feature, not per-handle.

 - when there are edges in mesh, it now only copies selection in edges
   when you have selectmode edge

 Slightly altered rule for the new IpoCurve option "Keep horizontal on
 extrema". It now also keeps auto-handles horizontal when the Y coordinate
 is exactly identical.
 
 This option is default on inserting new curve/keys.

[edit] IPO constraints

 - Button "Show" will make the IpoWindow show the Constraint Ipo
  (it didn't before, when IpoWindow was not set to correct mode)
 
 - Button "Key" will insert a key point on current frame (and show it in
   IpoWindow)
 
 Note that both options will create an Action too, if it didn't already exist.
 So, without opening an IpoWindow you can already animate Constraints.
 (Todo: use the auto key option to always insert on changing slider)
 
 Selecting a Bone will update the Constraint IpoWindow too. Note
 however, that when there are multiple Constraint Ipos on a Bone, it only
 shows the first... will solve that later.

[edit] IPO action and nla cleanup

 Stage two of the giant animation recode project; Ipo/Action/NLA cleanup
 
 Impatient people can check the goodies in CMS:
 http://www.blender3d.org/cms/Action_and_NLA_editor.706.0.html

 Now the goodies;
 - made Actions to allow any Ipo type
 - made NLA to define active actions, for Action window too
 - corrected timing for active action, so it shows the 'real time', as
   defined in NLA editor.

 New option; "Lock Time to Other Windows" for Ipo, Action, NLA and Time
 windows. If set (in View pulldown), it synchronizes the horizontal scale of
 the current window with the other Windows with this option set. That way
 you always have these windows showing an identical part of the time you
 work on.

[edit] 2.43 Release

[edit] IPO Editor Improvements

[edit] Mirror IPO Curve Points

This feature mirrors the selected keyframes in the active ipo curves over a user-nominated mirror-line. One time where this is handy is when creating ipos for driven shape keys, where you often have a left and right shape for something, where one of the curves is the opposite of the other. Rather than manually moving the keys or scaling them by a negative scale factor, you can now simply mirror those points.

Options are: - Mirror over current frame - Mirror over vertical axis (x = 0) - Mirror over horizontal axis (y = 0)

Functionality can be accessed from: - Hotkey Shift M in IPO editor - Submenu in header of IPO editor

[edit] Grab - Axis Locking

Transforms in the IPO editor lacked support for axis locking when performing transforms. This created confusion and annoyance due to lack of consistency between different parts of Blender.

It is now possible to only tranform selected keyframes/curves along a certain axis by pressing the key with that axis' name (i.e. X for only along x-axis, Y for only along y-axis).

[edit] Smooth Ipo Curves

This tool 'smoothes' the selected keyframes in the selected ipo-curves.

It takes the mean (average) value of the keyframes, and repositions each keyframe half-way between this average value and the keyframe's original value.

Hotkey for Smooth IPO is Shift O

[edit] Only needed keyframing

• 'Only Needed' Keyframing Option: This patch adds a new keyframing option for objects and bones. It only adds keyframes where they are needed, judging

from the surrounding points on that curve.

Notes about this keyframing option:

• Works like the existing 'Avail' option, except it checks if the keyframe is needed.
• Currently uses hardcoded threshold for determining if same value.

Cases where keyframes should not be added:

• 1. Keyframe to be added bewteen two keyframes with similar values
• 2. Keyframe to be added between two keyframes with similar times
• 3. Keyframe lies at point that intersects the linear line between two keyframes

[edit] needed keyframes

Auto-Keyframing Option: 'Needed': Now, when auto-keyframing, there is the option to have 'cleaner' ipo curves. This is a user-pref option, and is based on the same code responsible for the 'Only Needed' keyframing mode.