== Limit Distance Constraint ==

Added a new constraint, "Limit Distance". This constraint defines a 'virtual sphere' around the target which the owner can be made to stay inside, outside, or on the surface of it. 

This constraint is best used when applied using the Ctrl-Alt-C hotkey, as the radius is set correctly that way. 
One usage, is to prevent the target of an IK-chain from straying away from the chain. Care should be taken to not use a member of the IK-chain as the target though.

Description of Variables:
* 'Dist' - Radius of virtual sphere
* 'R' - Click on this to recalculate the 'Dist' value (note: like the 'R' button in the StretchTo constraint, this is currently buggy)
' Mode' - This menu gives different options for how the limiting sphere should act. The mode names are self explanatory.
* 'Soft' and 'SoftDistance' - currently not functional (so settings are hidden). These are used to define a smaller radius around the sphere of influence where a non-linear relationship between input and resulting locations occurs to prevent the owner 'crashing' into the sphere.

1 files changed, 24 insertions, 1 deletions

diff --git a/source/blender/makesdna/DNA_constraint_types.h b/source/blender/makesdna/DNA_constraint_types.h
index 4ae8d6b39e6..2bcf2412588 100644
--- a/source/blender/makesdna/DNA_constraint_types.h
+++ b/source/blender/makesdna/DNA_constraint_types.h
@@ -307,6 +307,19 @@ typedef struct bSizeLimitConstraint {
 	short		flag2;
 } bSizeLimitConstraint;
 
+/* Limit Distance Constraint */
+typedef struct bDistLimitConstraint {
+	Object 		*tar;
+	char 		subtarget[32];
+	
+	float 		dist;			/* distance (radius of clamping sphere) from target */
+	float		soft;			/* distance from clamping-sphere to start applying 'fade' */
+	
+	short		flag;			/* settings */
+	short 		mode;			/* how to limit in relation to clamping sphere */
+	int 		pad;
+} bDistLimitConstraint;
+
 /* ------------------------------------------ */
 
 /* bConstraint->type 
@@ -328,13 +341,14 @@ typedef enum B_CONSTAINT_TYPES {
 	CONSTRAINT_TYPE_PYTHON,				/* Unimplemented no longer :) - Aligorith. Scripts */
 	CONSTRAINT_TYPE_ACTION,
 	CONSTRAINT_TYPE_LOCKTRACK,			/* New Tracking constraint that locks an axis in place - theeth */
-	CONSTRAINT_TYPE_DISTANCELIMIT,		/* was never properly coded - removed! */
+	CONSTRAINT_TYPE_DISTLIMIT,			/* limit distance */
 	CONSTRAINT_TYPE_STRETCHTO, 			/* claiming this to be mine :) is in tuhopuu bjornmose */ 
 	CONSTRAINT_TYPE_MINMAX,  			/* floor constraint */
 	CONSTRAINT_TYPE_RIGIDBODYJOINT,		/* rigidbody constraint */
 	CONSTRAINT_TYPE_CLAMPTO, 			/* clampto constraint */	
 	CONSTRAINT_TYPE_TRANSFORM,			/* transformation (loc/rot/size -> loc/rot/size) constraint */	
 	
+	
 	/* NOTE: everytime a new constraint is added, update this */
 	NUM_CONSTRAINT_TYPES= CONSTRAINT_TYPE_TRANSFORM
 } B_CONSTRAINT_TYPES; 
@@ -478,6 +492,15 @@ typedef enum B_CONSTRAINTCHANNEL_FLAG {
 #define LIMIT_NOPARENT 0x01
 	/* for all Limit constraints - allow to be used during transform? */
 #define LIMIT_TRANSFORM 0x02
+
+/* distance limit constraint */
+	/* bDistLimitConstraint->flag */
+#define LIMITDIST_USESOFT		(1<<0)
+
+	/* bDistLimitConstraint->mode */
+#define LIMITDIST_INSIDE		0
+#define LIMITDIST_OUTSIDE		1
+#define LIMITDIST_ONSURFACE		2
 	
 /* python constraint -> flag */
 #define PYCON_USETARGETS	0x01