diff --git a/release/scripts/startup/bl_ui/properties_constraint.py b/release/scripts/startup/bl_ui/properties_constraint.py
index 4baf31a591b..e6b62cae6ef 100644
--- a/release/scripts/startup/bl_ui/properties_constraint.py
+++ b/release/scripts/startup/bl_ui/properties_constraint.py
@@ -502,6 +502,20 @@ class ConstraintButtonsPanel():
         row.operator("constraint.stretchto_reset", text="Reset")
 
         layout.prop(con, "bulge", text="Volume Variation")
+        split = layout.split()
+        col = split.column(align=True)
+        col.prop(con, "use_bulge_min", text="Volume Min")
+        sub = col.column()
+        sub.active = con.use_bulge_min
+        sub.prop(con, "bulge_min", text="")
+        col = split.column(align=True)
+        col.prop(con, "use_bulge_max", text="Volume Max")
+        sub = col.column()
+        sub.active = con.use_bulge_max
+        sub.prop(con, "bulge_max", text="")
+        col = layout.column()
+        col.active = con.use_bulge_min or con.use_bulge_max
+        col.prop(con, "bulge_smooth", text="Smooth")
 
         row = layout.row()
         row.label(text="Volume:")
diff --git a/source/blender/blenkernel/intern/constraint.c b/source/blender/blenkernel/intern/constraint.c
index ee7bad773fa..e4b60c12d64 100644
--- a/source/blender/blenkernel/intern/constraint.c
+++ b/source/blender/blenkernel/intern/constraint.c
@@ -2658,7 +2658,7 @@ static void stretchto_evaluate(bConstraint *con, bConstraintOb *cob, ListBase *t
 	if (VALID_CONS_TARGET(ct)) {
 		float size[3], scale[3], vec[3], xx[3], zz[3], orth[3];
 		float totmat[3][3];
-		float dist;
+		float dist, bulge;
 		
 		/* store scaling before destroying obmat */
 		mat4_to_size(size, cob->matrix);
@@ -2676,7 +2676,7 @@ static void stretchto_evaluate(bConstraint *con, bConstraintOb *cob, ListBase *t
 /*		vec[2] /= size[2];*/
 		
 /*		dist = normalize_v3(vec);*/
-		
+
 		dist = len_v3v3(cob->matrix[3], ct->matrix[3]);
 		/* Only Y constrained object axis scale should be used, to keep same length when scaling it. */
 		dist /= size[1];
@@ -2684,23 +2684,60 @@ static void stretchto_evaluate(bConstraint *con, bConstraintOb *cob, ListBase *t
 		/* data->orglength==0 occurs on first run, and after 'R' button is clicked */
 		if (data->orglength == 0)
 			data->orglength = dist;
-		if (data->bulge == 0)
-			data->bulge = 1.0;
-		
+
 		scale[1] = dist / data->orglength;
+		
+		bulge = powf(data->orglength / dist, data->bulge);
+		
+		if (data->flag & STRETCHTOCON_USE_BULGE_MAX) {
+			const float bulge_median = ((data->flag & STRETCHTOCON_USE_BULGE_MIN) ?
+			                            0.5f * (data->bulge_min + data->bulge_max) : 0.0f);
+			const float bulge_range = data->bulge_max - bulge_median;
+			float x, bulge_smoothed;
+
+			x = bulge_range != 0.0f ? (bulge - bulge_median) / bulge_range : 0.0f;
+			CLAMP(x, -1.0f, 1.0f);
+			bulge_smoothed = bulge_median + bulge_range * sinf(0.5f*M_PI * x);
+
+			if (data->flag & STRETCHTOCON_USE_BULGE_MIN) {
+				CLAMP_MIN(bulge, data->bulge_min);
+			}
+			CLAMP_MAX(bulge, data->bulge_max);
+
+			bulge = interpf(bulge_smoothed, bulge, data->bulge_smooth);
+		}
+		else if (data->flag & STRETCHTOCON_USE_BULGE_MIN) {
+			/* The quadratic formula below creates a smooth asymptote
+			 * of the clamped bulge value. By scaling x with the inverse smooth factor
+			 * the smoothed area becomes smaller ("less smoothing").
+			 * For very small smoothing factor below epsilon it is replaced
+			 * by the clamped version to avoid floating point precision issues.
+			 */
+			const float epsilon = 0.000001f;
+			if (data->bulge_smooth < epsilon) {
+				CLAMP_MIN(bulge, data->bulge_min);
+			}
+			else {
+				float scale = data->bulge_smooth;
+				float inv_scale = 1.0f / scale;
+				float x = (bulge - data->bulge_min) * 0.5f * inv_scale;
+				bulge = scale * (x + sqrtf((x * x) + 1.0f)) + data->bulge_min;
+			}
+		}
+		
 		switch (data->volmode) {
 			/* volume preserving scaling */
 			case VOLUME_XZ:
-				scale[0] = 1.0f - sqrtf(data->bulge) + sqrtf(data->bulge * (data->orglength / dist));
+				scale[0] = sqrtf(bulge);
 				scale[2] = scale[0];
 				break;
 			case VOLUME_X:
-				scale[0] = 1.0f + data->bulge * (data->orglength / dist - 1);
+				scale[0] = bulge;
 				scale[2] = 1.0;
 				break;
 			case VOLUME_Z:
 				scale[0] = 1.0;
-				scale[2] = 1.0f + data->bulge * (data->orglength / dist - 1);
+				scale[2] = bulge;
 				break;
 			/* don't care for volume */
 			case NO_VOLUME:
diff --git a/source/blender/makesdna/DNA_constraint_types.h b/source/blender/makesdna/DNA_constraint_types.h
index 0277956cac5..fb33879e2c1 100644
--- a/source/blender/makesdna/DNA_constraint_types.h
+++ b/source/blender/makesdna/DNA_constraint_types.h
@@ -284,10 +284,14 @@ typedef struct bFollowPathConstraint {
 /* Stretch to constraint */
 typedef struct bStretchToConstraint {
 	struct Object		*tar;
+	int			flag;
 	int			volmode; 
-	int         plane;
+	int			plane;
 	float		orglength;
 	float		bulge;
+	float		bulge_min;
+	float		bulge_max;
+	float		bulge_smooth;
 	char		subtarget[64];	/* MAX_ID_NAME-2 */
 } bStretchToConstraint;
 
@@ -820,6 +824,12 @@ typedef enum eObjectSolver_Flags {
 #define CONSTRAINT_DRAW_PIVOT 0x40
 #define 	CONSTRAINT_DISABLE_LINKED_COLLISION 0x80
 
+/* ObjectSolver Constraint -> flag */
+typedef enum eStretchTo_Flags {
+	STRETCHTOCON_USE_BULGE_MIN = (1 << 0),
+	STRETCHTOCON_USE_BULGE_MAX = (1 << 1),
+} eStretchTo_Flags;
+
 /* important: these defines need to match up with PHY_DynamicTypes headerfile */
 #define 	CONSTRAINT_RB_BALL		1
 #define 	CONSTRAINT_RB_HINGE		2
diff --git a/source/blender/makesrna/intern/rna_constraint.c b/source/blender/makesrna/intern/rna_constraint.c
index 5519b192ca4..aab2d35c0e4 100644
--- a/source/blender/makesrna/intern/rna_constraint.c
+++ b/source/blender/makesrna/intern/rna_constraint.c
@@ -1365,6 +1365,31 @@ static void rna_def_constraint_stretch_to(BlenderRNA *brna)
 	RNA_def_property_range(prop, 0.0, 100.f);
 	RNA_def_property_ui_text(prop, "Volume Variation", "Factor between volume variation and stretching");
 	RNA_def_property_update(prop, NC_OBJECT | ND_CONSTRAINT, "rna_Constraint_update");
+
+	prop = RNA_def_property(srna, "use_bulge_min", PROP_BOOLEAN, PROP_NONE);
+	RNA_def_property_boolean_sdna(prop, NULL, "flag", STRETCHTOCON_USE_BULGE_MIN);
+	RNA_def_property_ui_text(prop, "Use Volume Variation Minimum", "Use lower limit for volume variation");
+	RNA_def_property_update(prop, NC_OBJECT | ND_CONSTRAINT, "rna_Constraint_update");
+
+	prop = RNA_def_property(srna, "use_bulge_max", PROP_BOOLEAN, PROP_NONE);
+	RNA_def_property_boolean_sdna(prop, NULL, "flag", STRETCHTOCON_USE_BULGE_MAX);
+	RNA_def_property_ui_text(prop, "Use Volume Variation Maximum", "Use upper limit for volume variation");
+	RNA_def_property_update(prop, NC_OBJECT | ND_CONSTRAINT, "rna_Constraint_update");
+
+	prop = RNA_def_property(srna, "bulge_min", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_range(prop, 0.0, 100.f);
+	RNA_def_property_ui_text(prop, "Volume Variation Minimum", "Minimum volume stretching factor");
+	RNA_def_property_update(prop, NC_OBJECT | ND_CONSTRAINT, "rna_Constraint_update");
+
+	prop = RNA_def_property(srna, "bulge_max", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_range(prop, 0.0, 100.f);
+	RNA_def_property_ui_text(prop, "Volume Variation Maximum", "Maximum volume stretching factor");
+	RNA_def_property_update(prop, NC_OBJECT | ND_CONSTRAINT, "rna_Constraint_update");
+
+	prop = RNA_def_property(srna, "bulge_smooth", PROP_FLOAT, PROP_FACTOR);
+	RNA_def_property_range(prop, 0.0, 1.0f);
+	RNA_def_property_ui_text(prop, "Volume Variation Smoothness", "");
+	RNA_def_property_update(prop, NC_OBJECT | ND_CONSTRAINT, "rna_Constraint_update");
 }
 
 static void rna_def_constraint_rigid_body_joint(BlenderRNA *brna)