Added an option in the IK constraint to disable stretching, useful

in rigs with layered IK constraints. Also removed the tolerance
setting, this value wasn't used in the solver anymore.

7 files changed, 37 insertions, 26 deletions

diff --git a/source/blender/blenkernel/BKE_armature.h b/source/blender/blenkernel/BKE_armature.h
index 1ce5f7d0f03..684e69e7694 100644
--- a/source/blender/blenkernel/BKE_armature.h
+++ b/source/blender/blenkernel/BKE_armature.h
@@ -63,8 +63,8 @@ typedef struct PoseTree
 	int		*parent;				/* and their parents */
 	int		totchannel;				/* number of pose channels */
 	float	(*basis_change)[3][3]; 	/* basis change result from solver */
-	float	tolerance;				/* tolerance from the constraint */
 	int		iterations;				/* iterations from the constraint */
+	int     stretch;				/* disable stretching */
 } PoseTree;
 
 /*	Core armature functionality */
diff --git a/source/blender/blenkernel/intern/armature.c b/source/blender/blenkernel/intern/armature.c
index 570a9d3d589..4ea02565b9b 100644
--- a/source/blender/blenkernel/intern/armature.c
+++ b/source/blender/blenkernel/intern/armature.c
@@ -1118,9 +1118,9 @@ static void initialize_posetree(struct Object *ob, bPoseChannel *pchan_tip)
 		/* make new tree */
 		tree= MEM_callocN(sizeof(PoseTree), "posetree");
 
-		tree->tolerance= data->tolerance;
 		tree->iterations= data->iterations;
 		tree->totchannel= segcount;
+		tree->stretch = (data->flag & CONSTRAINT_IK_STRETCH);
 		
 		tree->pchan= MEM_callocN(segcount*sizeof(void*), "ik tree pchan");
 		tree->parent= MEM_callocN(segcount*sizeof(int), "ik tree parent");
@@ -1134,8 +1134,8 @@ static void initialize_posetree(struct Object *ob, bPoseChannel *pchan_tip)
 		BLI_addtail(&pchan_root->iktree, tree);
 	}
 	else {
-		tree->tolerance= MIN2(tree->tolerance, data->tolerance);
 		tree->iterations= MAX2(data->iterations, tree->iterations);
+		tree->stretch= tree->stretch && !(data->flag & CONSTRAINT_IK_STRETCH);
 
 		/* skip common pose channels and add remaining*/
 		size= MIN2(segcount, tree->totchannel);
@@ -1216,7 +1216,7 @@ static void execute_posetree(Object *ob, PoseTree *tree)
 		if((pchan->ikflag & BONE_IK_NO_ZDOF) == 0)
 			flag |= IK_ZDOF;
 
-		if(pchan->ikstretch > 0.0) {
+		if(tree->stretch && (pchan->ikstretch > 0.0)) {
 			flag |= IK_TRANS_YDOF;
 			hasstretch = 1;
 		}
@@ -1281,7 +1281,7 @@ static void execute_posetree(Object *ob, PoseTree *tree)
 		IK_SetStiffness(seg, IK_Y, pchan->stiffness[1]);
 		IK_SetStiffness(seg, IK_Z, pchan->stiffness[2]);
 
-		if(pchan->ikstretch > 0.0) {
+		if(tree->stretch && (pchan->ikstretch > 0.0)) {
 			float ikstretch = pchan->ikstretch*pchan->ikstretch;
 			IK_SetStiffness(seg, IK_TRANS_Y, MIN2(1.0-ikstretch, 0.99));
 			IK_SetLimit(seg, IK_TRANS_Y, 0.001, 1e10);
@@ -1352,7 +1352,7 @@ static void execute_posetree(Object *ob, PoseTree *tree)
 	}
 
 	/* solve */
-	IK_Solve(solver, tree->tolerance, tree->iterations);
+	IK_Solve(solver, 0.0f, tree->iterations);
 	IK_FreeSolver(solver);
 
 	/* gather basis changes */
@@ -1370,7 +1370,7 @@ static void execute_posetree(Object *ob, PoseTree *tree)
 			pchan= tree->pchan[a];
 			parentstretch= (tree->parent[a] >= 0)? ikstretch[tree->parent[a]]: 1.0;
 
-			if(pchan->ikstretch > 0.0) {
+			if(tree->stretch && (pchan->ikstretch > 0.0)) {
 				float trans[3], length;
 
 				IK_GetTranslationChange(iktree[a], trans);
diff --git a/source/blender/blenkernel/intern/constraint.c b/source/blender/blenkernel/intern/constraint.c
index d78dd31fb60..351f4e84a6b 100644
--- a/source/blender/blenkernel/intern/constraint.c
+++ b/source/blender/blenkernel/intern/constraint.c
@@ -563,10 +563,10 @@ void *new_constraint_data (short type)
 			bKinematicConstraint *data;
 			data = MEM_callocN(sizeof(bKinematicConstraint), "kinematicConstraint");
 
-			data->tolerance = (float)0.001;
 			data->weight= (float)1.0;
+			data->orientweight= (float)1.0;
 			data->iterations = 500;
-			data->flag= CONSTRAINT_IK_TIP;
+			data->flag= CONSTRAINT_IK_TIP|CONSTRAINT_IK_STRETCH|CONSTRAINT_IK_POS;
 			
 			result = data;
 		}
diff --git a/source/blender/blenloader/intern/readfile.c b/source/blender/blenloader/intern/readfile.c
index 39ba28912fd..1ce1f2c7237 100644
--- a/source/blender/blenloader/intern/readfile.c
+++ b/source/blender/blenloader/intern/readfile.c
@@ -5764,6 +5764,13 @@ static void do_versions(FileData *fd, Library *lib, Main *main)
 									data->flag&=~MINMAX_STICKY;
 								}
 							}
+							else if (curcon->type == CONSTRAINT_TYPE_KINEMATIC){
+								bKinematicConstraint *data = curcon->data;
+								if (!(data->flag & CONSTRAINT_IK_POS)) {
+									data->flag |= CONSTRAINT_IK_POS;
+									data->flag |= CONSTRAINT_IK_STRETCH;
+								}
+							}
 						}
 					}
 				}
diff --git a/source/blender/makesdna/DNA_constraint_types.h b/source/blender/makesdna/DNA_constraint_types.h
index 8b8f8ae0f72..aa9625bd31b 100644
--- a/source/blender/makesdna/DNA_constraint_types.h
+++ b/source/blender/makesdna/DNA_constraint_types.h
@@ -62,16 +62,15 @@ typedef struct bConstraint{
 /* Single-target subobject constraints */
 typedef struct bKinematicConstraint{
 	Object		*tar;
-	float		tolerance;		/* Acceptable distance from target */
 	short		iterations;		/* Maximum number of iterations to try */
 	short		flag;			/* Like CONSTRAINT_IK_TIP */
-	int			rootbone, pad;	/* index to rootbone, if zero go all the way to mother bone */
+	int			rootbone;	/* index to rootbone, if zero go all the way to mother bone */
 	char		subtarget[32];	/* String to specify sub-object target */
 
 	float		weight;			/* Weight of goal in IK tree */
 	float		orientweight;	/* Amount of rotation a target applies on chain */
 	float		grabtarget[3];	/* for target-less IK */
-	float		pad2;
+	int			pad;
 } bKinematicConstraint;
 
 typedef struct bTrackToConstraint{
@@ -277,6 +276,8 @@ typedef struct bSizeLimitConstraint{
 #define CONSTRAINT_IK_ROT		2
 #define CONSTRAINT_IK_AUTO		4
 #define CONSTRAINT_IK_TEMP		8
+#define CONSTRAINT_IK_STRETCH	16
+#define CONSTRAINT_IK_POS		32
 
 /* MinMax (floor) flags */
 #define MINMAX_STICKY	0x01
diff --git a/source/blender/python/api2_2x/Constraint.c b/source/blender/python/api2_2x/Constraint.c
index 2657ed51a72..e8a0566c89e 100644
--- a/source/blender/python/api2_2x/Constraint.c
+++ b/source/blender/python/api2_2x/Constraint.c
@@ -67,7 +67,7 @@ enum constraint_constants {
 	EXPP_CONSTR_MINZ = TRACK_nZ,
 
 	EXPP_CONSTR_TARGET = 100,
-	EXPP_CONSTR_TOLERANCE,
+	EXPP_CONSTR_STRETCH,
 	EXPP_CONSTR_ITERATIONS,
 	EXPP_CONSTR_BONE,
 	EXPP_CONSTR_CHAINLEN,
@@ -390,8 +390,8 @@ static PyObject *kinematic_getter( BPy_Constraint * self, int type )
 		return Object_CreatePyObject( con->tar );
 	case EXPP_CONSTR_BONE:
 		return PyString_FromString( con->subtarget );
-	case EXPP_CONSTR_TOLERANCE:
-		return PyFloat_FromDouble( (double)con->tolerance );
+	case EXPP_CONSTR_STRETCH:
+		return PyBool_FromLong( (long)( con->flag & CONSTRAINT_IK_STRETCH ) ) ;
 	case EXPP_CONSTR_ITERATIONS:
 		return PyInt_FromLong( (long)con->iterations );
 	case EXPP_CONSTR_CHAINLEN:
@@ -432,8 +432,8 @@ static int kinematic_setter( BPy_Constraint *self, int type, PyObject *value )
 
 		return 0;
 		}
-	case EXPP_CONSTR_TOLERANCE:
-		return EXPP_setFloatClamped( value, &con->tolerance, 0.0001, 1.0 );
+	case EXPP_CONSTR_STRETCH:
+		return EXPP_setBitfield( value, &con->flag, CONSTRAINT_IK_STRETCH, 'h' );
 	case EXPP_CONSTR_ITERATIONS:
 		return EXPP_setIValueClamped( value, &con->iterations, 1, 10000, 'h' );
 	case EXPP_CONSTR_CHAINLEN:
@@ -1829,8 +1829,8 @@ static PyObject *M_Constraint_SettingsDict( void )
 
 		PyConstant_Insert( d, "TARGET",
 				PyInt_FromLong( EXPP_CONSTR_TARGET ) );
-		PyConstant_Insert( d, "TOLERANCE", 
-				PyInt_FromLong( EXPP_CONSTR_TOLERANCE ) );
+		PyConstant_Insert( d, "STRETCH", 
+				PyInt_FromLong( EXPP_CONSTR_STRETCH ) );
 		PyConstant_Insert( d, "ITERATIONS", 
 				PyInt_FromLong( EXPP_CONSTR_ITERATIONS ) );
 		PyConstant_Insert( d, "BONE", 
diff --git a/source/blender/src/buttons_object.c b/source/blender/src/buttons_object.c
index 8f05e20af0c..1dbd0a653cb 100644
--- a/source/blender/src/buttons_object.c
+++ b/source/blender/src/buttons_object.c
@@ -757,7 +757,7 @@ static void draw_constraint (uiBlock *block, ListBase *list, bConstraint *con, s
 			{
 				bKinematicConstraint *data = con->data;
 				
-				height = 108;
+				height = 111;
 				uiDefBut(block, ROUNDBOX, B_DIFF, "", *xco-10, *yco-height, width+40,height-1, NULL, 5.0, 0.0, 12, rb_col, ""); 
 				
 				uiDefBut(block, LABEL, B_CONSTRAINT_TEST, "Target:", *xco+65, *yco-24, 50, 18, NULL, 0.0, 0.0, 0.0, 0.0, ""); 
@@ -776,14 +776,17 @@ static void draw_constraint (uiBlock *block, ListBase *list, bConstraint *con, s
 					strcpy (data->subtarget, "");
 	
 				uiBlockBeginAlign(block);
-				uiDefButBitS(block, TOG, CONSTRAINT_IK_TIP, B_CONSTRAINT_TEST, "Use Tip", *xco, *yco-64, 142, 19, &data->flag, 0, 0, 0, 0, "Include Bone's tip als last element in Chain");
-				uiDefButI(block, NUM, B_CONSTRAINT_TEST, "ChainLen:", *xco+142, *yco-64,143,19, &data->rootbone, 0, 255, 0, 0, "If not zero, the amount of bones in this chain");
+				uiDefButBitS(block, TOG, CONSTRAINT_IK_TIP, B_CONSTRAINT_TEST, "Use Tip", *xco, *yco-64, 137, 19, &data->flag, 0, 0, 0, 0, "Include Bone's tip als last element in Chain");
+				uiDefButI(block, NUM, B_CONSTRAINT_TEST, "ChainLen:", *xco, *yco-84,137,19, &data->rootbone, 0, 255, 0, 0, "If not zero, the amount of bones in this chain");
 				
 				uiBlockBeginAlign(block);
-				uiDefButF(block, NUMSLI, B_CONSTRAINT_TEST, "PosW ", *xco, *yco-86, 142, 19, &data->weight, 0.01, 1.0, 2, 2, "For Tree-IK: weight of position control for this target");
-				uiDefButF(block, NUMSLI, B_CONSTRAINT_TEST, "RotW ", *xco+142, *yco-86, 143, 19, &data->orientweight, 0.01, 1.0, 2, 2, "For Tree-IK: Weight of orientation control for this target");
-				uiDefButF(block, NUM, B_CONSTRAINT_TEST, "Tolerance:", *xco, *yco-106, 142, 19, &data->tolerance, 0.0001f, 1.0, 0, 0, "Maximum distance to target after solving"); 
-				uiDefButS(block, NUM, B_CONSTRAINT_TEST, "Iterations:", *xco+142, *yco-106, 143, 19, &data->iterations, 1, 10000, 0, 0, "Maximum number of solving iterations"); 
+				uiDefButF(block, NUMSLI, B_CONSTRAINT_TEST, "PosW ", *xco+147, *yco-64, 137, 19, &data->weight, 0.01, 1.0, 2, 2, "For Tree-IK: weight of position control for this target");
+				uiDefButF(block, NUMSLI, B_CONSTRAINT_TEST, "RotW ", *xco+147, *yco-84, 137, 19, &data->orientweight, 0.01, 1.0, 2, 2, "For Tree-IK: Weight of orientation control for this target");
+
+				uiBlockBeginAlign(block);
+				uiDefButS(block, NUM, B_CONSTRAINT_TEST, "Iterations:", *xco, *yco-109, 137, 19, &data->iterations, 1, 10000, 0, 0, "Maximum number of solving iterations"); 
+				uiBlockBeginAlign(block);
+				uiDefButBitS(block, TOG, CONSTRAINT_IK_STRETCH, B_CONSTRAINT_TEST, "Stretch", *xco+147, *yco-109,137,19, &data->flag, 0, 0, 0, 0, "Enable IK stretching");
 				
 			}
 			break;