Support for auto-skinning when parenting a mesh to an armature.

Applies to bones that do not have a boneclass of unskinnable
(set per bone in editmode in the button window).

source/blender/blenkernel/BKE_armature.h

@@ -77,6 +77,7 @@ struct Bone *get_named_bone (struct bArmature *arm, const char *name);
 struct Bone *get_indexed_bone (struct bArmature *arm, int index);
 void make_displists_by_armature (struct Object *ob);
 void calc_bone_deform (struct Bone *bone, float weight, float *vec, float *co, float *contrib);
+float dist_to_bone (float vec[3], float b1[3], float b2[3]);
 
 void where_is_armature_time (struct Object *ob, float ctime);
 void where_is_armature (struct Object *ob);

source/blender/blenkernel/BKE_subsurf.h

@@ -39,6 +39,7 @@ void subsurf_to_mesh(struct Object *oldob, struct Mesh *newme);
 void subsurf_make_mesh(struct Object *ob, short subdiv);
 void subsurf_make_editmesh(struct Object *ob);
 struct DispList* subsurf_mesh_to_displist(struct Mesh *me, struct DispList *dl, short subdiv);
+void subsurf_calculate_limit_positions(Mesh *me, float (*positions_r)[3]);
 
 #endif
 

source/blender/blenkernel/intern/armature.c

@@ -73,7 +73,6 @@
 /*	Function prototypes */
 
 static void apply_pose_bonechildren (Bone* bone, bPose* pose, int doit);
-static float dist_to_bone (float vec[3], float b1[3], float b2[3]);
 static Bone *get_named_bone_bonechildren (Bone *bone, const char *name);
 static Bone *get_indexed_bone_bonechildren (Bone *bone, int *index);
 /*void make_bone_parent_matrix (Bone* bone);*/
@@ -568,7 +567,7 @@ static int verify_boneptr_children (Bone *cBone, Bone *tBone)
 }
 
 
-static float dist_to_bone (float vec[3], float b1[3], float b2[3])
+float dist_to_bone (float vec[3], float b1[3], float b2[3])
 {
 /*  	float dist=0; */
 	float bdelta[3];

source/blender/blenkernel/intern/subsurf.c

@@ -901,3 +901,44 @@ DispList* subsurf_mesh_to_displist(Mesh *me, DispList *dl, short subdiv)
 
 	return subsurf_subdivide_to_displist(hme, subdiv);
 }
+
+void subsurf_calculate_limit_positions(Mesh *me, float (*positions_r)[3]) 
+{
+	/* Finds the subsurf limit positions for the verts in a mesh 
+	 * and puts them in an array of floats. Please note that the 
+	 * calculated vert positions is incorrect for the verts 
+	 * on the boundary of the mesh.
+	 */
+	HyperMesh *hme= hypermesh_from_mesh(me, NULL);
+	HyperMesh *nme= hypermesh_new();
+	float edge_sum[3], face_sum[3];
+	HyperVert *hv;
+	LinkNode *l;
+	int i;
+
+	hypermesh_subdivide(hme, nme);
+
+	for (i= me->totvert-1,hv=hme->verts; i>=0; i--,hv=hv->next) {
+		int N= 0;
+                
+		edge_sum[0]= edge_sum[1]= edge_sum[2]= 0.0;
+		face_sum[0]= face_sum[1]= face_sum[2]= 0.0;
+
+		for (N=0,l=hv->edges; l; N++,l= l->next) {
+			Vec3Add(edge_sum, ((HyperEdge*) l->link)->ep->co);
+		}
+		for (l=hv->faces; l; l= l->next) {
+			Vec3Add(face_sum, ((HyperFace*) l->link)->mid->co);
+		}
+
+		positions_r[i][0] = 
+			(hv->nmv->co[0]*N*N + edge_sum[0]*4 + face_sum[0])/(N*(N+5));
+		positions_r[i][1] = 
+			(hv->nmv->co[1]*N*N + edge_sum[1]*4 + face_sum[1])/(N*(N+5));
+		positions_r[i][2] = 
+			(hv->nmv->co[2]*N*N + edge_sum[2]*4 + face_sum[2])/(N*(N+5));
+	}
+
+	hypermesh_free(nme);
+	hypermesh_free(hme);
+}

source/blender/include/BIF_editarmature.h

@@ -73,6 +73,7 @@ typedef struct EditBone
 	float rot[3], drot[3];
 	float quat[4], dquat[4];
 	float obmat[4][4];
+	short boneclass;
 
 
 } EditBone;
@@ -106,6 +107,7 @@ void	selectconnected_posearmature(void);
 void	select_bone_by_name (struct bArmature *arm, char *name, int select);
 struct	Bone *get_first_selected_bone (void);
 void auto_align_armature(void);
+void create_vgroups_from_armature(Object *ob, Object *par);
 
 #define	BONESEL_TIP		0x08000000
 #define	BONESEL_ROOT	0x04000000

source/blender/include/BIF_editdeform.h

@@ -33,12 +33,18 @@
 #ifndef BIF_DEFORM_H
 #define BIF_DEFORM_H
 
+#define WEIGHT_REPLACE  1
+#define WEIGHT_ADD      2
+#define WEIGHT_SUBTRACT 3
+
 struct Object;
 struct MDeformVert;
 struct MDeformWeight;
 struct bDeformGroup;
 
+struct bDeformGroup *get_named_vertexgroup (Object *ob, char *name);
 void unique_vertexgroup_name (struct bDeformGroup *dg, struct Object *ob);
+struct bDeformGroup *add_defgroup_name (struct Object *ob, char *name);
 void add_defgroup (struct Object *ob);
 void del_defgroup (struct Object *ob);
 void assign_verts_defgroup (void);
@@ -46,6 +52,12 @@ void remove_verts_defgroup (int allverts);
 void sel_verts_defgroup (int select);
 struct MDeformWeight *verify_defweight (struct MDeformVert *dv, int defgroup);
 void verify_defgroups (struct Object *ob);
+int  get_defgroup_num (struct Object *ob, struct bDeformGroup   *dg);
+void add_vert_to_defgroup (struct Object *ob, struct bDeformGroup *dg, 
+						   int vertnum, float weight, 
+						   int assignmode);
+void remove_vert_defgroup (struct Object *ob, struct bDeformGroup  *dg, 
+						   int vertnum);
 
 #endif
 

source/blender/makesdna/DNA_armature_types.h

@@ -61,6 +61,10 @@ typedef struct Bone {
 	float defmat[4][4];
 	float irestmat[4][4];	/*	Cached inverse of rest matrix (objectspace)*/
 	float posemat[4][4];	/*	Cached pose matrix (objectspace)*/
+	short boneclass;
+	short filler1;
+	short filler2;
+	short filler3;
 }Bone;
 
 typedef struct bArmature {
@@ -119,5 +123,22 @@ enum {
 		BONE_ISMUSCLEBIT
 };
 
-#endif
+enum {
+		BONE_SKINNABLE  =       0,
+		BONE_UNSKINNABLE,
+		BONE_HEAD,
+		BONE_NECK,
+		BONE_BACK,
+		BONE_SHOULDER,
+		BONE_ARM,
+		BONE_HAND,
+		BONE_FINGER,
+		BONE_THUMB,
+		BONE_PELVIS,
+		BONE_LEG,
+		BONE_FOOT,
+		BONE_TOE,
+		BONE_TENTACLE
+};
 
+#endif

source/blender/src/editarmature.c

@@ -58,6 +58,7 @@
 #include "DNA_screen_types.h"
 #include "DNA_space_types.h"
 #include "DNA_view3d_types.h"
+#include "DNA_mesh_types.h"
 
 #include "BKE_utildefines.h"
 #include "BKE_action.h"
@@ -65,6 +66,7 @@
 #include "BKE_constraint.h"
 #include "BKE_global.h"
 #include "BKE_object.h"
+#include "BKE_subsurf.h"
 
 #include "BIF_gl.h"
 #include "BIF_graphics.h"
@@ -76,6 +78,7 @@
 #include "BIF_editarmature.h"
 #include "BIF_poseobject.h"
 #include "BIF_mywindow.h"
+#include "BIF_editdeform.h"
 
 #include "BDR_editobject.h"
 #include "BDR_drawobject.h"
@@ -810,6 +813,8 @@ static void editbones_to_armature (ListBase *list, Object *ob)
 
 		newBone->weight = eBone->weight;
 		newBone->dist = eBone->dist;
+		newBone->boneclass = eBone->boneclass;
+
 		memcpy (newBone->loc, eBone->loc, sizeof(eBone->loc));
 		memcpy (newBone->dloc, eBone->dloc, sizeof(eBone->dloc));
 /*		memcpy (newBone->orig, eBone->orig, sizeof(eBone->orig));*/
@@ -906,6 +911,8 @@ void load_editArmature(void)
 
 		newBone->weight = eBone->weight;
 		newBone->dist = eBone->dist;
+		newBone->boneclass = eBone->boneclass;
+
 		memcpy (newBone->loc, eBone->loc, sizeof(eBone->loc));
 		memcpy (newBone->dloc, eBone->dloc, sizeof(eBone->dloc));
 /*		memcpy (newBone->orig, eBone->orig, sizeof(eBone->orig));*/
@@ -1081,6 +1088,7 @@ static void make_boneList(ListBase* list, ListBase *bones, EditBone *parent)
 #endif		
 		eBone->dist= curBone->dist;
 		eBone->weight= curBone->weight;
+		eBone->boneclass = curBone->boneclass;
 		memcpy (eBone->loc, curBone->loc, sizeof(curBone->loc));
 		memcpy (eBone->dloc, curBone->dloc, sizeof(curBone->dloc));
 		/*		memcpy (eBone->orig, curBone->orig, sizeof(curBone->orig));*/
@@ -1587,6 +1595,7 @@ static void add_bone_input (Object *ob)
 		
 		bone->weight= 1.0F;
 		bone->dist= 1.0F;
+		bone->boneclass = BONE_SKINNABLE;
 
 		/*	Project cursor center to screenspace. */
 		getmouseco_areawin(mval);
@@ -1781,8 +1790,35 @@ void armaturebuts(void)
 
 				/* Dist and weight buttons */
 				uiBlockSetCol(block, BUTGREY);
-				uiDefButF(block, NUM,REDRAWVIEW3D, "Dist:", bx+320, by, 110, 18, &curBone->dist, 0.0, 1000.0, 10.0, 0.0, "Bone deformation distance");
+				but=uiDefButI(block, MENU, REDRAWVIEW3D,
-				uiDefButF(block, NUM,REDRAWVIEW3D, "Weight:", bx+438, by, 110, 18, &curBone->weight, 0.0F, 1000.0F, 10.0F, 0.0F, "Bone deformation weight");
+							  "Skinnable %x0|"
+							  "Unskinnable %x1|"
+							  "Head %x2|"
+							  "Neck %x3|"
+							  "Back %x4|"
+							  "Shoulder %x5|"
+							  "Arm %x6|"
+							  "Hand %x7|"
+							  "Finger %x8|"
+							  "Thumb %x9|"
+							  "Pelvis %x10|"
+							  "Leg %x11|"
+							  "Foot %x12|"
+							  "Toe %x13|"
+							  "Tentacle %x14",
+							  bx+320,by,97,18,
+							  &curBone->boneclass,
+							  0.0, 0.0, 0.0, 0.0, 
+							  "Classification of armature element");
+				
+				/* Dist and weight buttons */
+				uiBlockSetCol(block, BUTGREY);
+				uiDefButF(block, NUM,REDRAWVIEW3D, "Dist:", bx+425, by, 
+						  110, 18, &curBone->dist, 0.0, 1000.0, 10.0, 0.0, 
+						  "Bone deformation distance");
+				uiDefButF(block, NUM,REDRAWVIEW3D, "Weight:", bx+543, by, 
+						  110, 18, &curBone->weight, 0.0F, 1000.0F, 
+						  10.0F, 0.0F, "Bone deformation weight");
 				
 				by-=19;	
 			}
@@ -2108,6 +2144,8 @@ void extrude_armature(void)
 			newbone->flag |= BONE_QUATROT;
 			newbone->weight= curbone->weight;
 			newbone->dist= curbone->dist;
+			newbone->boneclass= curbone->boneclass;
+
 			Mat4One(newbone->obmat);
 			
 			/* See if there are any ik children of the parent */
@@ -2586,3 +2624,324 @@ void auto_align_armature(void)
 	}
 } 
 
+int bone_looper(Object *ob, Bone *bone, void *data,
+                        int (*bone_func)(Object *, Bone *, void *)) {
+
+    /* We want to apply the function bone_func to every bone 
+     * in an armature -- feed bone_looper the first bone and 
+     * a pointer to the bone_func and watch it go!. The int count 
+     * can be useful for counting bones with a certain property
+     * (e.g. skinnable)
+     */
+    int count = 0;
+
+    if (bone) {
+
+        /* only do bone_func if the bone is non null
+         */
+        count += bone_func(ob, bone, data);
+
+        /* try to execute bone_func for the first child
+         */
+        count += bone_looper(ob, bone->childbase.first, data,
+                                    bone_func);
+
+        /* try to execute bone_func for the next bone at this
+         * depth of the recursion.
+         */
+        count += bone_looper(ob, bone->next, data, bone_func);
+    }
+
+    return count;
+}
+
+int add_defgroup_unique_bone(Object *ob, Bone *bone, void *data) {
+    /* This group creates a vertex group to ob that has the
+     * same name as bone. Is such a vertex group aleady exist
+     * the routine exits.
+     */
+    if (!get_named_vertexgroup(ob,bone->name)) {
+        add_defgroup_name(ob, bone->name);
+        return 1;
+    }
+    return 0;
+}
+
+int bone_skinnable(Object *ob, Bone *bone, void *data)
+{
+    /* Bones that are not of boneclass BONE_UNSKINNABLE
+     * are regarded to be "skinnable" and are eligible for
+     * auto-skinning.
+     *
+     * This function performs 2 functions:
+     *
+     *   a) It returns 1 if the bone is skinnable.
+     *      If we loop over all bones with this 
+     *      function, we can count the number of
+     *      skinnable bones.
+     *   b) If the pointer data is non null,
+     *      it is treated like a handle to a
+     *      bone pointer -- the bone pointer
+     *      is set to point at this bone, and
+     *      the pointer the handle points to
+     *      is incremented to point to the
+     *      next member of an array of pointers
+     *      to bones. This way we can loop using
+     *      this function to construct an array of
+     *      pointers to bones that point to all
+     *      skinnable bones.
+     */
+    Bone ***hbone;
+
+    if ( bone->boneclass != BONE_UNSKINNABLE ) {
+		if (data != NULL) {
+			hbone = (Bone ***) data;
+            **hbone = bone;
+            ++*hbone;
+        }
+        return 1;
+    }
+    return 0;
+}
+
+int dgroup_skinnable(Object *ob, Bone *bone, void *data) {
+    /* Bones that are not of boneclass BONE_UNSKINNABLE
+     * are regarded to be "skinnable" and are eligible for
+     * auto-skinning.
+     *
+     * This function performs 2 functions:
+     *
+     *   a) If the bone is skinnable, it creates 
+     *      a vertex group for ob that has
+     *      the name of the skinnable bone
+     *      (if one doesn't exist already).
+     *   b) If the pointer data is non null,
+     *      it is treated like a handle to a
+     *      bDeformGroup pointer -- the 
+     *      bDeformGroup pointer is set to point
+     *      to the deform group with the bone's
+     *      name, and the pointer the handle 
+     *      points to is incremented to point to the
+     *      next member of an array of pointers
+     *      to bDeformGroups. This way we can loop using
+     *      this function to construct an array of
+     *      pointers to bDeformGroups, all with names
+     *      of skinnable bones.
+     */
+    bDeformGroup ***hgroup, *defgroup;
+
+    if ( bone->boneclass != BONE_UNSKINNABLE ) {
+        if ( !(defgroup = get_named_vertexgroup(ob, bone->name)) ) {
+            defgroup = add_defgroup_name(ob, bone->name);
+        }
+
+        if (data != NULL) {
+            hgroup = (bDeformGroup ***) data;
+            **hgroup = defgroup;
+            ++*hgroup;
+        }
+        return 1;
+    }
+    return 0;
+}
+
+void add_verts_to_closest_dgroup(Object *ob, Object *par)
+{
+    /* This function implements a crude form of 
+     * auto-skinning: vertices are assigned to the
+     * deformation groups associated with bones based
+     * on thier proximity to a bone. Every vert is
+     * given a weight of 1.0 to the weight group
+     * cooresponding to the bone that it is
+     * closest to. The vertex may also be assigned to
+     * a deformation group associated to a bone
+     * that is within 10% of the mninimum distance
+     * between the bone and the nearest vert -- the
+     * cooresponding weight will fall-off to zero
+     * as the distance approaches the 10% tolerance mark.
+	 * If the mesh has subsurf enabled then the verts
+	 * on the subsurf limit surface is used to generate 
+	 * the weights rather than the verts on the cage
+	 * mesh.
+     */
+
+    bArmature *arm;
+    Bone **bonelist, **bonehandle, *bone;
+    bDeformGroup **dgrouplist, **dgrouphandle, *defgroup;
+    float *distance, mindist = 0.0, weight = 0.0;
+    float   root[3];
+    float   tip[3];
+    float real_co[3];
+	float *subverts = NULL;
+    float *subvert;
+    Mesh  *mesh;
+    MVert *vert;
+
+    int numbones, i, j;
+
+    /* If the parent object is not an armature exit */
+    arm = get_armature(par);
+    if (!arm)
+        return;
+
+    /* count the number of skinnable bones */
+    numbones = bone_looper(ob, arm->bonebase.first, NULL,
+                                  bone_skinnable);
+
+    /* create an array of pointer to bones that are skinnable
+     * and fill it with all of the skinnable bones
+     */
+    bonelist = MEM_mallocN(numbones*sizeof(Bone *), "bonelist");
+    bonehandle = bonelist;
+    bone_looper(ob, arm->bonebase.first, &bonehandle,
+                       bone_skinnable);
+
+    /* create an array of pointers to the deform groups that
+     * coorespond to the skinnable bones (creating them
+     * as necessary.
+     */
+    dgrouplist = MEM_mallocN(numbones*sizeof(bDeformGroup *), "dgrouplist");
+    dgrouphandle = dgrouplist;
+    bone_looper(ob, arm->bonebase.first, &dgrouphandle,
+                       dgroup_skinnable);
+
+    /* create an array of floats that will be used for each vert
+     * to hold the distance to each bone.
+     */
+    distance = MEM_mallocN(numbones*sizeof(float), "distance");
+
+    mesh = (Mesh*)ob->data;
+
+	/* Is subsurf on? Lets use the verts on the limit surface then */
+	if ( (mesh->flag&ME_SUBSURF) && (mesh->subdiv > 0) ) {
+		subverts = MEM_mallocN(3*mesh->totvert*sizeof(float), "subverts");
+		subsurf_calculate_limit_positions(mesh, subverts);
+	}
+
+    /* for each vertex in the mesh ...
+     */
+    for ( i=0 ; i < mesh->totvert ; ++i ) {
+        /* get the vert in global coords
+         */
+		
+		if (subverts) {
+			subvert = subverts + i*3;
+			VECCOPY (real_co, subvert);
+		}
+		else {
+			vert = mesh->mvert + i;
+			VECCOPY (real_co, vert->co);
+		}
+        Mat4MulVecfl(ob->obmat, real_co);
+
+
+        /* for each skinnable bone ...
+         */
+        for (j=0; j < numbones; ++j) {
+            bone = bonelist[j];
+
+            /* get the root of the bone in global coords
+             */
+            get_bone_root_pos (bone, root, 0);
+            Mat4MulVecfl(par->obmat, root);
+
+            /* get the tip of the bone in global coords
+             */
+            get_bone_tip_pos (bone, tip, 0);
+            Mat4MulVecfl(par->obmat, tip);
+
+            /* store the distance from the bone to
+             * the vert
+             */
+            distance[j] = dist_to_bone(real_co, root, tip);
+
+            /* if this is the first bone, or if this
+             * bone is less than mindist, then set this
+             * distance to mindist
+             */
+            if (j == 0) {
+                mindist = distance[j];
+            }
+            else if (distance[j] < mindist) {
+                mindist = distance[j];
+            }
+        }
+
+        /* for each deform group ...
+         */
+        for (j=0; j < numbones; ++j) {
+            defgroup = dgrouplist[j];
+
+            /* if the cooresponding bone is the closest one
+             * add the vert to the deform group with weight 1
+             */
+            if (distance[j] <= mindist) {
+                add_vert_to_defgroup (ob, defgroup, i, 1.0, WEIGHT_REPLACE);
+            }
+
+            /* if the cooresponding bone is within 10% of the
+             * nearest distance, add the vert to the
+             * deform group with a weight that declines with
+             * distance
+             */
+            else if (distance[j] <= mindist*1.10) {
+                if (mindist > 0)
+                    weight = 1.0 - (distance[j] - mindist) / (mindist * 0.10);
+                add_vert_to_defgroup (ob, defgroup, i, weight, WEIGHT_REPLACE);
+            }
+            
+            /* if the cooresponding bone is outside of the 10% tolerance
+             * then remove the vert from the weight group (if it is
+             * in that group)
+             */
+            else {
+                remove_vert_defgroup (ob, defgroup, i);
+            }
+        }
+    }
+
+    /* free the memory allocated
+     */
+    MEM_freeN(bonelist);
+    MEM_freeN(dgrouplist);
+    MEM_freeN(distance);
+	if (subverts) MEM_freeN(subverts);
+}
+
+void create_vgroups_from_armature(Object *ob, Object *par)
+{
+	/* Lets try to create some vertex groups 
+	 * based on the bones of the parent armature.
+	 */
+
+	bArmature *arm;
+	short mode;
+
+	/* If the parent object is not an armature exit */
+	arm = get_armature(par);
+	if (!arm)
+		return;
+
+	/* Prompt the user on whether/how they want the vertex groups
+	 * added to the child mesh */
+	mode= pupmenu("Vertex Groups from Bones? %t|No Thanks %x1|Empty %x2|"
+				  "Closest Bone %x3");
+	switch (mode){
+	case 2:
+		/* Traverse the bone list, trying to create empty vertex 
+		 * groups cooresponding to the bone.
+		 */
+		bone_looper(ob, arm->bonebase.first, NULL,
+					add_defgroup_unique_bone);
+		break;
+
+	case 3:
+		/* Traverse the bone list, trying to create vertex groups 
+		 * that are populated with the vertices for which the
+		 * bone is closest.
+		 */
+		add_verts_to_closest_dgroup(ob, par);
+		break;
+
+	}
+} 

source/blender/src/editdeform.c

@@ -114,20 +114,32 @@ the specified defweight group */
 	return dv->dw+(dv->totweight-1);
 }
 
-void add_defgroup (Object *ob)
+void add_defgroup (Object *ob) {
+	add_defgroup_name (ob, "Group");
+}
+
+bDeformGroup *add_defgroup_name (Object *ob, char *name)
 {
 	bDeformGroup	*defgroup;
-
+	
 	if (!ob)
-		return;
+		return NULL;
-
+	
 	defgroup = MEM_callocN (sizeof(bDeformGroup), "deformGroup");
-	strcpy (defgroup->name, "Group");
+
+	/* I think there should be some length
+	 * checking here -- don't know why NaN
+	 * never checks name lengths (see
+	 * unique_vertexgroup_name, for example).
+	 */
+	strcpy (defgroup->name, name);
 
 	BLI_addtail(&ob->defbase, defgroup);
 	unique_vertexgroup_name(defgroup, ob);
 
 	ob->actdef = BLI_countlist(&ob->defbase);
+
+	return defgroup;
 }
 
 void del_defgroup (Object *ob)
@@ -166,6 +178,233 @@ void del_defgroup (Object *ob)
 	BLI_freelinkN (&ob->defbase, defgroup);
 }
 
+void create_dverts(Mesh *me)
+{
+	/* create deform verts for the mesh
+	 */
+	int i;
+
+	me->dvert= MEM_mallocN(sizeof(MDeformVert)*me->totvert, "deformVert");
+	for (i=0; i < me->totvert; ++i) {
+		me->dvert[i].totweight = 0;
+		me->dvert[i].dw        = NULL;
+	}
+}
+
+int  get_defgroup_num (Object *ob, bDeformGroup	*dg)
+{
+	/* Fetch the location of this deform group
+	 * within the linked list of deform groups.
+	 * (this number is stored in the deform
+	 * weights of the deform verts to link them
+	 * to this deform group) deform deform
+	 * deform blah blah deform
+	 */
+
+	bDeformGroup	*eg;
+	int def_nr;
+
+	eg = ob->defbase.first;
+	def_nr = 0;
+
+	/* loop through all deform groups
+	 */
+	while (eg != NULL){
+
+		/* if the current deform group is
+		 * the one we are after, return
+		 * def_nr
+		 */
+		if (eg == dg){
+			break;
+		}
+		++def_nr;
+		eg = eg->next;
+	}
+
+	/* if there was no deform group found then
+	 * return -1 (should set up a nice symbolic
+	 * constant for this)
+	 */
+	if (eg == NULL) return -1;
+	
+	return def_nr;
+    
+}
+
+
+void remove_vert_def_nr (Object *ob, int def_nr, int vertnum)
+{
+	/* This routine removes the vertex from the deform
+	 * group with number def_nr.
+	 *
+	 * This routine is meant to be fast, so it is the
+	 * responsibility of the calling routine to:
+	 *   a) test whether ob is non-NULL
+	 *   b) test whether ob is a mesh
+	 *   c) calculate def_nr
+	 */
+
+	MDeformWeight *newdw;
+	MDeformVert *dvert;
+	int i;
+
+	/* if this mesh has no deform mesh abort
+	 */
+	if (!((Mesh*)ob->data)->dvert) return;
+
+	/* get the deform mesh cooresponding to the
+	 * vertnum
+	 */
+	dvert = ((Mesh*)ob->data)->dvert + vertnum;
+
+	/* for all of the deform weights in the
+	 * deform vert
+	 */
+	for (i=dvert->totweight - 1 ; i>=0 ; i--){
+
+		/* if the def_nr is the same as the one
+		 * for our weight group then remove it
+		 * from this deform vert.
+		 */
+		if (dvert->dw[i].def_nr == def_nr) {
+			dvert->totweight--;
+        
+			/* if there are still other deform weights
+			 * attached to this vert then remove this
+			 * deform weight, and reshuffle the others
+			 */
+			if (dvert->totweight) {
+				newdw = MEM_mallocN (sizeof(MDeformWeight)*(dvert->totweight), 
+									 "deformWeight");
+				if (dvert->dw){
+					memcpy (newdw, dvert->dw, sizeof(MDeformWeight)*i);
+					memcpy (newdw+i, dvert->dw+i+1, 
+							sizeof(MDeformWeight)*(dvert->totweight-i));
+					MEM_freeN (dvert->dw);
+				}
+				dvert->dw=newdw;
+			}
+			/* if there are no other deform weights
+			 * left then just remove the deform weight
+			 */
+			else {
+				MEM_freeN (dvert->dw);
+				dvert->dw = NULL;
+			}
+		}
+	}
+
+}
+
+void add_vert_defnr (Object *ob, int def_nr, int vertnum, 
+                           float weight, int assignmode)
+{
+	/* add the vert to the deform group with the
+	 * specified number
+	 */
+
+	MDeformVert *dv;
+	MDeformWeight *newdw;
+	int	i;
+
+	/* get the vert
+	 */
+	dv = ((Mesh*)ob->data)->dvert + vertnum;
+
+	/* Lets first check to see if this vert is
+	 * already in the weight group -- if so
+	 * lets update it
+	 */
+	for (i=0; i<dv->totweight; i++){
+		
+		/* if this weight cooresponds to the
+		 * deform group, then add it using
+		 * the assign mode provided
+		 */
+		if (dv->dw[i].def_nr == def_nr){
+			
+			switch (assignmode) {
+			case WEIGHT_REPLACE:
+				dv->dw[i].weight=weight;
+				break;
+			case WEIGHT_ADD:
+				dv->dw[i].weight+=weight;
+				if (dv->dw[i].weight >= 1.0)
+					dv->dw[i].weight = 1.0;
+				break;
+			case WEIGHT_SUBTRACT:
+				dv->dw[i].weight-=weight;
+				/* if the weight is zero or less then
+				 * remove the vert from the deform group
+				 */
+				if (dv->dw[i].weight <= 0.0)
+					remove_vert_def_nr(ob, def_nr, vertnum);
+				break;
+			}
+			return;
+		}
+	}
+
+	/* if the vert wasn't in the deform group then
+	 * we must take a different form of action ...
+	 */
+
+	switch (assignmode) {
+	case WEIGHT_SUBTRACT:
+		/* if we are subtracting then we don't
+		 * need to do anything
+		 */
+		return;
+
+	case WEIGHT_REPLACE:
+	case WEIGHT_ADD:
+		/* if we are doing an additive assignment, then
+		 * we need to create the deform weight
+		 */
+		newdw = MEM_callocN (sizeof(MDeformWeight)*(dv->totweight+1), 
+							 "deformWeight");
+		if (dv->dw){
+			memcpy (newdw, dv->dw, sizeof(MDeformWeight)*dv->totweight);
+			MEM_freeN (dv->dw);
+		}
+		dv->dw=newdw;
+    
+		dv->dw[dv->totweight].weight=weight;
+		dv->dw[dv->totweight].def_nr=def_nr;
+    
+		dv->totweight++;
+		break;
+	}
+}
+
+void add_vert_to_defgroup (Object *ob, bDeformGroup *dg, int vertnum, 
+                           float weight, int assignmode)
+{
+	/* add the vert to the deform group with the
+	 * specified assign mode
+	 */
+	int	def_nr;
+
+	/* get the deform group number, exit if
+	 * it can't be found
+	 */
+	def_nr = get_defgroup_num(ob, dg);
+	if (def_nr < 0) return;
+
+	/* if this mesh has no deform verts then
+	 * create some
+	 */
+	if (!((Mesh*)ob->data)->dvert) {
+		create_dverts((Mesh*)ob->data);
+	}
+
+	/* call another function to do the work
+	 */
+	add_vert_defnr (ob, def_nr, vertnum, weight, assignmode);
+}
+
+
 void assign_verts_defgroup (void)
 /* Only available in editmode */
 {
@@ -230,6 +469,35 @@ void assign_verts_defgroup (void)
 
 }
 
+void remove_vert_defgroup (Object *ob, bDeformGroup	*dg, int vertnum)
+{
+	/* This routine removes the vertex from the specified
+	 * deform group.
+	 */
+
+	int def_nr;
+
+	/* if the object is NULL abort
+	 */
+	if (!ob)
+		return;
+
+	/* if this isn't a mesh abort
+	 */
+	if (ob->type != OB_MESH) return;
+
+	/* get the deform number that cooresponds
+	 * to this deform group, and abort if it
+	 * can not be found.
+	 */
+	def_nr = get_defgroup_num(ob, dg);
+	if (def_nr < 0) return;
+
+	/* call another routine to do the work
+	 */
+	remove_vert_def_nr (ob, def_nr, vertnum);
+}
+
 void remove_verts_defgroup (int allverts)
 /* Only available in editmode */
 {
@@ -286,12 +554,18 @@ void remove_verts_defgroup (int allverts)
 
 void verify_defgroups (Object *ob)
 {
-		/* Ensure the defbase & the dverts match */
+	/* Ensure the defbase & the dverts match */
 	switch (ob->type){
 	case OB_MESH:
+
+		/* I'm pretty sure this means "If there are no
+		 * deform groups defined, yet there are deform
+		 * vertices, then delete the deform vertices
+		 */
 		if (!ob->defbase.first){
 			if (((Mesh*)ob->data)->dvert){
-				free_dverts(((Mesh*)ob->data)->dvert, ((Mesh*)ob->data)->totvert);
+				free_dverts(((Mesh*)ob->data)->dvert, 
+							((Mesh*)ob->data)->totvert);
 				((Mesh*)ob->data)->dvert=NULL;
 			}
 		}
@@ -301,6 +575,22 @@ void verify_defgroups (Object *ob)
 	}
 }
 
+bDeformGroup *get_named_vertexgroup(Object *ob, char *name)
+{
+	/* return a pointer to the deform group with this name
+	 * or return NULL otherwise.
+	 */
+	bDeformGroup *curdef;
+
+	for (curdef = ob->defbase.first; curdef; curdef=curdef->next){
+		if (!strcmp(curdef->name, name)){
+			return curdef;
+		}
+	}
+	return NULL;
+}
+
+
 void unique_vertexgroup_name (bDeformGroup *dg, Object *ob)
 {
 	char		tempname[64];

source/blender/src/editobject.c

@@ -850,7 +850,14 @@ void make_parent(void)
 							memset(base->object->loc, 0, 3*sizeof(float));
 						}
 						else {
-						if(mode==PARSKEL && par->type == OB_ARMATURE) {
+							if(mode==PARSKEL && par->type == OB_ARMATURE) {
+								/* Prompt the user as to whether he wants to
+								 * add some vertex groups based on the bones
+								 * in the parent armature.
+								 */
+								create_vgroups_from_armature(base->object, 
+															 par);
+
 								base->object->partype= PAROBJECT;
 								what_does_parent(base->object);
 								Mat4One (base->object->parentinv);