Three new features:

1) Stride Bone

For walkcycles, you could already set an NLA strip to cycle over a path
based on a preset distance value. This cycling happens based on a linear
interpolation, with constant speed.
Not all cycles have a constant speed however, like hopping or jumping.
To ensure a perfect slipping-less foot contact, you now can set a Bone
in an Armature to define the stride. This "Stride Bone" then becomes a
sort-of ruler, a conveyor belt, on which the character walks. When using
the NLA "Use Path" option, it then tries to keep the Stride Bone entirely
motionless on the path, by cancelling out its motion (for the entire
Armature). This means that the animation keys for a Stride Bone have to be
exactly negative of the desired path. Only, at choice, the X,Y or Z Ipo
curve is used for this stride.

Examples:

http://www.blender.org/bf/0001_0040.avi
The top armature shows the actual Action, the bottom armature has been
parented to a Path, using the Stride Bone feature.

http://www.blender.org/bf/0001_0080.avi
Here the Stride Bone has a number of children, creating a ruler to be
used as reference while animating.

Test .blend:
http://www.blender.org/bf/motionblender1.blend

Notes:
- Note that action keys for Bones work local, based on the Bone's
  orientation as set in EditMode. Therefore, an Y translation always
  goes in the Bone's direction.
- To be able to get a "solvable" stride, the animation curve has
  to be inverse evaluated, using a Newton Raphson root solver. That
  means you can only create stride curves that keep moving forward, and
  cannot return halfway.
- Set the Stride Bone in the Editing Buttons, Bone Panel. You can set
  change the name or set the axis in the NLA Window, Strip Properties Panel.
- Files in this commit will move to the blender.org release section.

2) Armature Ghosting

In EditButtons, Armature Panel, you can set an armature to draw ghosts.
The number value denotes the amount of frames that have to be drawn extra
(for the active action!) around the current frame.
Ghosts only evaluate its own Pose, executing it's Actions, Constraints and
IK. No external dependencies are re-evaluated for it.

3) NLA/Action time control

If you click in the NLA window on the action (linked to Object), it makes
sure the Timing as drawn in the Action editor is not corrected for NLA.
If you also set the Object to "Action", this timing will be executed on the
Object as well (not NLA time).
(It's a bit confusing... will make a good doc & maybe review UI!)

3 files changed, 10 insertions, 5 deletions

diff --git a/source/blender/makesdna/DNA_action_types.h b/source/blender/makesdna/DNA_action_types.h
index fce02e2e394..2f60045e9ea 100644
--- a/source/blender/makesdna/DNA_action_types.h
+++ b/source/blender/makesdna/DNA_action_types.h
@@ -138,7 +138,8 @@ enum	{
 	POSE_HAS_IK		=	0x0100,
 	POSE_CHAIN		=	0x0200,
 	POSE_DONE		=   0x0400,
-	POSE_KEY		=	0x1000
+	POSE_KEY		=	0x1000,
+	POSE_STRIDE		=	0x2000
 };
 
 /* PoseChannel constflag (constraint detection) */
@@ -147,6 +148,8 @@ enum	{
 	/* only used for drawing Posemode, not stored in channel */
 #define PCHAN_HAS_ACTION	4
 #define PCHAN_HAS_TARGET	8
+	/* only for drawing Posemode too */
+#define PCHAN_HAS_STRIDE	16
 
 /* PoseChannel->ikflag */
 #define		BONE_IK_NO_XDOF 1
diff --git a/source/blender/makesdna/DNA_armature_types.h b/source/blender/makesdna/DNA_armature_types.h
index 47ecccc1f1e..b31a803718e 100644
--- a/source/blender/makesdna/DNA_armature_types.h
+++ b/source/blender/makesdna/DNA_armature_types.h
@@ -77,7 +77,7 @@ typedef struct bArmature {
 	int			flag;
 	int			drawtype;			
 	int			deformflag;
-	int			res3;			
+	short		ghostep, pad;
 }bArmature;
 
 /* armature->flag */
diff --git a/source/blender/makesdna/DNA_nla_types.h b/source/blender/makesdna/DNA_nla_types.h
index 4d5483f71d7..bf3d7820dae 100644
--- a/source/blender/makesdna/DNA_nla_types.h
+++ b/source/blender/makesdna/DNA_nla_types.h
@@ -38,9 +38,8 @@ struct Ipo;
 
 typedef struct bActionStrip {
 	struct bActionStrip *next, *prev;
-	short	flag;
-	short	mode;
-	int		reserved1;
+	short	flag, mode;
+	short	stride_axis, pad;	/* axis 0=x, 1=y, 2=z */
 
 	struct	Ipo *ipo;			/* Blending ipo */
 	struct	bAction *act;		/* The action referenced by this strip */
@@ -51,6 +50,8 @@ typedef struct bActionStrip {
 	float	repeat;				/* The number of times to repeat the action range */
 
 	float	blendin, blendout;
+	
+	char	stridechannel[32];	/* Instead of stridelen, it uses an action channel */
 } bActionStrip;
 
 #define ACTSTRIPMODE_BLEND		0
@@ -64,5 +65,6 @@ typedef struct bActionStrip {
 #define ACTSTRIP_ACTIVE			0x10
 #define ACTSTRIP_LOCK_ACTION	0x20
 
+
 #endif