object_constraint.c

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/*
 * $Id: object_constraint.c 36473 2011-05-04 05:52:14Z campbellbarton $
 *
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): Joshua Leung, Blender Foundation
 *
 * ***** END GPL LICENSE BLOCK *****
 */

#include <stdio.h>
#include <string.h>

#include "MEM_guardedalloc.h"

#include "BLI_blenlib.h"
#include "BLI_math.h"
#include "BLI_dynstr.h"
#include "BLI_utildefines.h"

#include "DNA_constraint_types.h"
#include "DNA_curve_types.h"
#include "DNA_scene_types.h"
#include "DNA_text_types.h"
#include "DNA_object_types.h"

#include "BKE_action.h"
#include "BKE_armature.h"
#include "BKE_constraint.h"
#include "BKE_context.h"
#include "BKE_depsgraph.h"
#include "BKE_global.h"
#include "BKE_main.h"
#include "BKE_object.h"
#include "BKE_report.h"
#include "BIK_api.h"

#ifdef WITH_PYTHON
#include "BPY_extern.h"
#endif

#include "WM_api.h"
#include "WM_types.h"

#include "RNA_access.h"
#include "RNA_define.h"
#include "RNA_enum_types.h"

#include "ED_object.h"
#include "ED_armature.h"
#include "ED_screen.h"

#include "UI_interface.h"
#include "UI_resources.h"

#include "object_intern.h"

/* -------------- Get Active Constraint Data ---------------------- */

/* if object in posemode, active bone constraints, else object constraints */
ListBase *get_active_constraints (Object *ob)
{
        if (ob == NULL)
                return NULL;
        
        if (ob->mode & OB_MODE_POSE) {
                bPoseChannel *pchan;
                
                pchan = get_active_posechannel(ob);
                if (pchan)
                        return &pchan->constraints;
        }
        else 
                return &ob->constraints;
        
        return NULL;
}

/* Find the list that a given constraint belongs to, and/or also get the posechannel this is from (if applicable) */
ListBase *get_constraint_lb (Object *ob, bConstraint *con, bPoseChannel **pchan_r)
{
        if (pchan_r)
                *pchan_r= NULL;
        
        if (ELEM(NULL, ob, con))
                return NULL;
        
        /* try object constraints first */
        if ((BLI_findindex(&ob->constraints, con) != -1)) {
                return &ob->constraints;
        }
        
        /* if armature, try pose bones too */
        if (ob->pose) {
                bPoseChannel *pchan;
                
                /* try each bone in order 
                 * NOTE: it's not possible to directly look up the active bone yet, so this will have to do
                 */
                for (pchan= ob->pose->chanbase.first; pchan; pchan= pchan->next) {
                        if ((BLI_findindex(&pchan->constraints, con) != -1)) {
                                
                                if (pchan_r)
                                        *pchan_r= pchan;
                                
                                return &pchan->constraints;
                        }
                }
        }
        
        /* done */
        return NULL;
}

/* single constraint */
bConstraint *get_active_constraint (Object *ob)
{
        return constraints_get_active(get_active_constraints(ob));
}

/* -------------- Constraint Management (Add New, Remove, Rename) -------------------- */
/* ------------- PyConstraints ------------------ */

/* this callback sets the text-file to be used for selected menu item */
static void validate_pyconstraint_cb (void *arg1, void *arg2)
{
        bPythonConstraint *data = arg1;
        Text *text= NULL;
        int index = *((int *)arg2);
        int i;
        
        /* exception for no script */
        if (index) {
                /* innovative use of a for...loop to search */
                for (text=G.main->text.first, i=1; text && index!=i; i++, text=text->id.next);
        }
        data->text = text;
}

#ifdef WITH_PYTHON
/* this returns a string for the list of usable pyconstraint script names */
static char *buildmenu_pyconstraints (Text *con_text, int *pyconindex)
{
        DynStr *pupds= BLI_dynstr_new();
        Text *text;
        char *str;
        char buf[64];
        int i;
        
        /* add title first */
        sprintf(buf, "Scripts: %%t|[None]%%x0|");
        BLI_dynstr_append(pupds, buf);
        
        /* init active-index first */
        if (con_text == NULL)
                *pyconindex= 0;
        
        /* loop through markers, adding them */
        for (text=G.main->text.first, i=1; text; i++, text=text->id.next) {
                /* this is important to ensure that right script is shown as active */
                if (text == con_text) *pyconindex = i;
                
                /* only include valid pyconstraint scripts */
                if (BPY_is_pyconstraint(text)) {
                        BLI_dynstr_append(pupds, text->id.name+2);
                        
                        sprintf(buf, "%%x%d", i);
                        BLI_dynstr_append(pupds, buf);
                        
                        if (text->id.next)
                                BLI_dynstr_append(pupds, "|");
                }
        }
        
        /* convert to normal MEM_malloc'd string */
        str= BLI_dynstr_get_cstring(pupds);
        BLI_dynstr_free(pupds);
        
        return str;
}
#endif /* WITH_PYTHON */

#if 0 // UNUSED, until pyconstraints are added back.
/* this callback gets called when the 'refresh' button of a pyconstraint gets pressed */
static void update_pyconstraint_cb (void *arg1, void *arg2)
{
#ifndef WITH_PYTHON
        (void)arg1; /* unused */
        (void)arg2; /* unused */
#else
        Object *owner= (Object *)arg1;
        bConstraint *con= (bConstraint *)arg2;
        if (owner && con)
                BPY_pyconstraint_update(owner, con);
#endif
}
#endif // UNUSED

/* helper function for add_constriant - sets the last target for the active constraint */
static void set_constraint_nth_target (bConstraint *con, Object *target, const char subtarget[], int index)
{
        bConstraintTypeInfo *cti= constraint_get_typeinfo(con);
        ListBase targets = {NULL, NULL};
        bConstraintTarget *ct;
        int num_targets, i;
        
        if (cti && cti->get_constraint_targets) {
                cti->get_constraint_targets(con, &targets);
                num_targets= BLI_countlist(&targets);
                
                if (index < 0) {
                        if (abs(index) < num_targets)
                                index= num_targets - abs(index);
                        else
                                index= num_targets - 1;
                }
                else if (index >= num_targets) {
                        index= num_targets - 1;
                }
                
                for (ct=targets.first, i=0; ct; ct= ct->next, i++) {
                        if (i == index) {
                                ct->tar= target;
                                strcpy(ct->subtarget, subtarget);
                                break;
                        }
                }
                
                if (cti->flush_constraint_targets)
                        cti->flush_constraint_targets(con, &targets, 0);
        }
}

/* ------------- Constraint Sanity Testing ------------------- */

/* checks validity of object pointers, and NULLs,
 * if Bone doesnt exist it sets the CONSTRAINT_DISABLE flag.
 */
static void test_constraints (Object *owner, bPoseChannel *pchan)
{
        bConstraint *curcon;
        ListBase *conlist= NULL;
        int type;
        
        if (owner==NULL) return;
        
        /* Check parents */
        if (pchan) {
                switch (owner->type) {
                        case OB_ARMATURE:
                                type = CONSTRAINT_OBTYPE_BONE;
                                break;
                        default:
                                type = CONSTRAINT_OBTYPE_OBJECT;
                                break;
                }
        }
        else
                type = CONSTRAINT_OBTYPE_OBJECT;
        
        /* Get the constraint list for this object */
        switch (type) {
                case CONSTRAINT_OBTYPE_OBJECT:
                        conlist = &owner->constraints;
                        break;
                case CONSTRAINT_OBTYPE_BONE:
                        conlist = &pchan->constraints;
                        break;
        }
        
        /* Check all constraints - is constraint valid? */
        if (conlist) {
                for (curcon = conlist->first; curcon; curcon=curcon->next) {
                        bConstraintTypeInfo *cti= constraint_get_typeinfo(curcon);
                        ListBase targets = {NULL, NULL};
                        bConstraintTarget *ct;
                        
                        /* clear disabled-flag first */
                        curcon->flag &= ~CONSTRAINT_DISABLE;
                        
                        if (curcon->type == CONSTRAINT_TYPE_KINEMATIC) {
                                bKinematicConstraint *data = curcon->data;
                                
                                /* bad: we need a separate set of checks here as poletarget is 
                                 *              optional... otherwise poletarget must exist too or else
                                 *              the constraint is deemed invalid
                                 */
                                /* default IK check ... */
                                if (exist_object(data->tar) == 0) {
                                        data->tar = NULL;
                                        curcon->flag |= CONSTRAINT_DISABLE;
                                }
                                else if (data->tar == owner) {
                                        if (!get_named_bone(get_armature(owner), data->subtarget)) {
                                                curcon->flag |= CONSTRAINT_DISABLE;
                                        }
                                }
                                
                                if (data->poletar) {
                                        if (exist_object(data->poletar) == 0) {
                                                data->poletar = NULL;
                                                curcon->flag |= CONSTRAINT_DISABLE;
                                        }
                                        else if (data->poletar == owner) {
                                                if (!get_named_bone(get_armature(owner), data->polesubtarget)) {
                                                        curcon->flag |= CONSTRAINT_DISABLE;
                                                }
                                        }
                                }
                                /* ... can be overwritten here */
                                BIK_test_constraint(owner, curcon);
                                /* targets have already been checked for this */
                                continue;
                        }
                        else if (curcon->type == CONSTRAINT_TYPE_PIVOT) {
                                bPivotConstraint *data = curcon->data;
                                
                                /* target doesn't have to exist, but if it is non-null, it must exist! */
                                if (data->tar && exist_object(data->tar)==0) {
                                        data->tar = NULL;
                                        curcon->flag |= CONSTRAINT_DISABLE;
                                }
                                else if (data->tar == owner) {
                                        if (!get_named_bone(get_armature(owner), data->subtarget)) {
                                                curcon->flag |= CONSTRAINT_DISABLE;
                                        }
                                }
                                
                                /* targets have already been checked for this */
                                continue;
                        }
                        else if (curcon->type == CONSTRAINT_TYPE_ACTION) {
                                bActionConstraint *data = curcon->data;
                                
                                /* validate action */
                                if (data->act == NULL) 
                                        curcon->flag |= CONSTRAINT_DISABLE;
                        }
                        else if (curcon->type == CONSTRAINT_TYPE_FOLLOWPATH) {
                                bFollowPathConstraint *data = curcon->data;
                                
                                /* don't allow track/up axes to be the same */
                                if (data->upflag==data->trackflag)
                                        curcon->flag |= CONSTRAINT_DISABLE;
                                if (data->upflag+3==data->trackflag)
                                        curcon->flag |= CONSTRAINT_DISABLE;
                        }
                        else if (curcon->type == CONSTRAINT_TYPE_TRACKTO) {
                                bTrackToConstraint *data = curcon->data;
                                
                                /* don't allow track/up axes to be the same */
                                if (data->reserved2==data->reserved1)
                                        curcon->flag |= CONSTRAINT_DISABLE;
                                if (data->reserved2+3==data->reserved1)
                                        curcon->flag |= CONSTRAINT_DISABLE;
                        }
                        else if (curcon->type == CONSTRAINT_TYPE_LOCKTRACK) {
                                bLockTrackConstraint *data = curcon->data;
                                
                                if (data->lockflag==data->trackflag)
                                        curcon->flag |= CONSTRAINT_DISABLE;
                                if (data->lockflag+3==data->trackflag)
                                        curcon->flag |= CONSTRAINT_DISABLE;
                        }
                        else if (curcon->type == CONSTRAINT_TYPE_SPLINEIK) {
                                bSplineIKConstraint *data = curcon->data;
                                
                                /* if the number of points does not match the amount required by the chain length,
                                 * free the points array and request a rebind...
                                 */
                                if ((data->points == NULL) || (data->numpoints != data->chainlen+1))
                                {
                                        /* free the points array */
                                        if (data->points) {
                                                MEM_freeN(data->points);
                                                data->points = NULL;
                                        }
                                        
                                        /* clear the bound flag, forcing a rebind next time this is evaluated */
                                        data->flag &= ~CONSTRAINT_SPLINEIK_BOUND;
                                }
                        }
                        
                        /* Check targets for constraints */
                        if (cti && cti->get_constraint_targets) {
                                cti->get_constraint_targets(curcon, &targets);
                                
                                /* disable and clear constraints targets that are incorrect */
                                for (ct= targets.first; ct; ct= ct->next) {
                                        /* general validity checks (for those constraints that need this) */
                                        if (exist_object(ct->tar) == 0) {
                                                /* object doesn't exist, but constraint requires target */
                                                ct->tar = NULL;
                                                curcon->flag |= CONSTRAINT_DISABLE;
                                        }
                                        else if (ct->tar == owner) {
                                                if (type == CONSTRAINT_OBTYPE_BONE) {
                                                        if (!get_named_bone(get_armature(owner), ct->subtarget)) {
                                                                /* bone must exist in armature... */
                                                                // TODO: clear subtarget?
                                                                curcon->flag |= CONSTRAINT_DISABLE;
                                                        }
                                                        else if (strcmp(pchan->name, ct->subtarget) == 0) {
                                                                /* cannot target self */
                                                                ct->subtarget[0] = '\0';
                                                                curcon->flag |= CONSTRAINT_DISABLE;
                                                        }
                                                }
                                                else {
                                                        /* cannot use self as target */
                                                        ct->tar = NULL;
                                                        curcon->flag |= CONSTRAINT_DISABLE;
                                                }
                                        }
                                        
                                        /* target checks for specific constraints */
                                        if (ELEM3(curcon->type, CONSTRAINT_TYPE_FOLLOWPATH, CONSTRAINT_TYPE_CLAMPTO, CONSTRAINT_TYPE_SPLINEIK)) {
                                                if (ct->tar) {
                                                        if (ct->tar->type != OB_CURVE) {
                                                                ct->tar= NULL;
                                                                curcon->flag |= CONSTRAINT_DISABLE;
                                                        }
                                                        else {
                                                                Curve *cu= ct->tar->data;
                                                                
                                                                /* auto-set 'Path' setting on curve so this works  */
                                                                cu->flag |= CU_PATH;
                                                        }
                                                }                                               
                                        }
                                }       
                                
                                /* free any temporary targets */
                                if (cti->flush_constraint_targets)
                                        cti->flush_constraint_targets(curcon, &targets, 0);
                        }
                }
        }
}

void object_test_constraints (Object *owner)
{
        if (owner->constraints.first)
                test_constraints(owner, NULL);
        
        if (owner->type==OB_ARMATURE && owner->pose) {
                bPoseChannel *pchan;
                
                for (pchan= owner->pose->chanbase.first; pchan; pchan= pchan->next) {
                        if (pchan->constraints.first)
                                test_constraints(owner, pchan);
                }
        }
}


/************************ generic functions for operators using constraint names and data context *********************/

#define EDIT_CONSTRAINT_OWNER_OBJECT    0
#define EDIT_CONSTRAINT_OWNER_BONE              1

static EnumPropertyItem constraint_owner_items[] = {
        {EDIT_CONSTRAINT_OWNER_OBJECT, "OBJECT", 0, "Object", "Edit a constraint on the active object"},
        {EDIT_CONSTRAINT_OWNER_BONE, "BONE", 0, "Bone", "Edit a constraint on the active bone"},
        {0, NULL, 0, NULL, NULL}};


static int edit_constraint_poll_generic(bContext *C, StructRNA *rna_type)
{
        PointerRNA ptr= CTX_data_pointer_get_type(C, "constraint", rna_type);
        Object *ob= (ptr.id.data) ? ptr.id.data : ED_object_active_context(C);

        if (!ob || ob->id.lib) return 0;
        if (ptr.id.data && ((ID*)ptr.id.data)->lib) return 0;

        return 1;
}

static int edit_constraint_poll(bContext *C)
{
        return edit_constraint_poll_generic(C, &RNA_Constraint);
}

static void edit_constraint_properties(wmOperatorType *ot)
{
        RNA_def_string(ot->srna, "constraint", "", 32, "Constraint", "Name of the constraint to edit");
        RNA_def_enum(ot->srna, "owner", constraint_owner_items, 0, "Owner", "The owner of this constraint");
}

static int edit_constraint_invoke_properties(bContext *C, wmOperator *op)
{
        PointerRNA ptr= CTX_data_pointer_get_type(C, "constraint", &RNA_Constraint);
        Object *ob= (ptr.id.data)?ptr.id.data:ED_object_active_context(C);
        bConstraint *con;
        ListBase *list;
        
        if (RNA_property_is_set(op->ptr, "constraint") && RNA_property_is_set(op->ptr, "owner"))
                return 1;
        
        if (ptr.data) {
                con = ptr.data;
                RNA_string_set(op->ptr, "constraint", con->name);
                
                list = get_constraint_lb(ob, con, NULL);
                
                if (&ob->constraints == list)
                        RNA_enum_set(op->ptr, "owner", EDIT_CONSTRAINT_OWNER_OBJECT);
                else
                        RNA_enum_set(op->ptr, "owner", EDIT_CONSTRAINT_OWNER_BONE);
                
                return 1;
        }
        
        return 0;
}

static bConstraint *edit_constraint_property_get(wmOperator *op, Object *ob, int type)
{
        char constraint_name[32];
        int owner = RNA_enum_get(op->ptr, "owner");
        bConstraint *con;
        ListBase *list=NULL;
        
        RNA_string_get(op->ptr, "constraint", constraint_name);
        
        if (owner == EDIT_CONSTRAINT_OWNER_OBJECT) {
                list = &ob->constraints;
        } 
        else if (owner == EDIT_CONSTRAINT_OWNER_BONE) {
                bPoseChannel *pchan= get_active_posechannel(ob);
                if (pchan)
                        list = &pchan->constraints;
                else {
                        //if (G.f & G_DEBUG)
                        //printf("edit_constraint_property_get: No active bone for object '%s'\n", (ob)? ob->id.name+2 : "<None>");
                        return NULL;
                }
        }
        else {
                //if (G.f & G_DEBUG)
                //printf("edit_constraint_property_get: defaulting to getting list in the standard way\n");
                list = get_active_constraints(ob);
        }
        
        con = constraints_findByName(list, constraint_name);
        printf("constraint found = %p, %s\n", (void *)con, (con)?con->name:"<Not found>");

        if (con && (type != 0) && (con->type != type))
                con = NULL;
        
        return con;
}

/* ********************** CONSTRAINT-SPECIFIC STUFF ********************* */

/* ---------- Distance-Dependent Constraints ---------- */
/* StretchTo, Limit Distance */

static int stretchto_reset_exec (bContext *C, wmOperator *op)
{
        Object *ob = ED_object_active_context(C);
        bConstraint *con = edit_constraint_property_get(op, ob, CONSTRAINT_TYPE_STRETCHTO);
        bStretchToConstraint *data= (con) ? (bStretchToConstraint *)con->data : NULL;
        
        /* despite 3 layers of checks, we may still not be able to find a constraint */
        if (data == NULL)
                return OPERATOR_CANCELLED;
        
        /* just set original length to 0.0, which will cause a reset on next recalc */
        data->orglength = 0.0f;
        ED_object_constraint_update(ob);
        
        WM_event_add_notifier(C, NC_OBJECT|ND_CONSTRAINT, NULL);
        return OPERATOR_FINISHED;
}

static int stretchto_reset_invoke(bContext *C, wmOperator *op, wmEvent *UNUSED(event))
{
        if (edit_constraint_invoke_properties(C, op))
                return stretchto_reset_exec(C, op);
        else
                return OPERATOR_CANCELLED;
}

void CONSTRAINT_OT_stretchto_reset (wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Reset Original Length";
        ot->idname= "CONSTRAINT_OT_stretchto_reset";
        ot->description= "Reset original length of bone for Stretch To Constraint";
        
        ot->exec= stretchto_reset_exec;
        ot->invoke= stretchto_reset_invoke;
        ot->poll= edit_constraint_poll;
        
        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
        edit_constraint_properties(ot);
}


static int limitdistance_reset_exec (bContext *C, wmOperator *op)
{
        Object *ob = ED_object_active_context(C);
        bConstraint *con = edit_constraint_property_get(op, ob, CONSTRAINT_TYPE_DISTLIMIT);
        bDistLimitConstraint *data= (con) ? (bDistLimitConstraint *)con->data : NULL;
        
        /* despite 3 layers of checks, we may still not be able to find a constraint */
        if (data == NULL)
                return OPERATOR_CANCELLED;
        
        /* just set original length to 0.0, which will cause a reset on next recalc */
        data->dist = 0.0f;
        ED_object_constraint_update(ob);
        
        WM_event_add_notifier(C, NC_OBJECT|ND_CONSTRAINT, NULL);
        return OPERATOR_FINISHED;
}

static int limitdistance_reset_invoke(bContext *C, wmOperator *op, wmEvent *UNUSED(event))
{
        if (edit_constraint_invoke_properties(C, op))
                return limitdistance_reset_exec(C, op);
        else
                return OPERATOR_CANCELLED;
}

void CONSTRAINT_OT_limitdistance_reset (wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Reset Distance";
        ot->idname= "CONSTRAINT_OT_limitdistance_reset";
        ot->description= "Reset limiting distance for Limit Distance Constraint";
        
        ot->exec= limitdistance_reset_exec;
        ot->invoke= limitdistance_reset_invoke;
        ot->poll= edit_constraint_poll;
        
        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
        edit_constraint_properties(ot);
}

/* ------------- Child-Of Constraint ------------------ */

/* ChildOf Constraint - set inverse callback */
static int childof_set_inverse_exec (bContext *C, wmOperator *op)
{
        Scene *scene= CTX_data_scene(C);
        Object *ob = ED_object_active_context(C);
        bConstraint *con = edit_constraint_property_get(op, ob, CONSTRAINT_TYPE_CHILDOF);
        bChildOfConstraint *data= (con) ? (bChildOfConstraint *)con->data : NULL;
        bPoseChannel *pchan= NULL;
        
        /* despite 3 layers of checks, we may still not be able to find a constraint */
        if (data == NULL) {
                printf("DEBUG: Child-Of Set Inverse - object = '%s'\n", (ob)? ob->id.name+2 : "<None>");
                BKE_report(op->reports, RPT_ERROR, "Couldn't find constraint data for Child-Of Set Inverse");
                return OPERATOR_CANCELLED;
        }
        
        /* try to find a pose channel */
        // TODO: get from context instead?
        if (ob && ob->pose)
                pchan= get_active_posechannel(ob);
        
        /* calculate/set inverse matrix */
        if (pchan) {
                float pmat[4][4], cinf;
                float imat[4][4], tmat[4][4];
                
                /* make copy of pchan's original pose-mat (for use later) */
                copy_m4_m4(pmat, pchan->pose_mat);
                
                /* disable constraint for pose to be solved without it */
                cinf= con->enforce;
                con->enforce= 0.0f;
                
                /* solve pose without constraint */
                where_is_pose(scene, ob);
                
                /* determine effect of constraint by removing the newly calculated 
                 * pchan->pose_mat from the original pchan->pose_mat, thus determining 
                 * the effect of the constraint
                 */
                invert_m4_m4(imat, pchan->pose_mat);
                mul_m4_m4m4(tmat, imat, pmat);
                invert_m4_m4(data->invmat, tmat);
                
                /* recalculate pose with new inv-mat */
                con->enforce= cinf;
                where_is_pose(scene, ob);
        }
        else if (ob) {
                Object workob;
                /* use what_does_parent to find inverse - just like for normal parenting.
                 * NOTE: what_does_parent uses a static workob defined in object.c 
                 */
                what_does_parent(scene, ob, &workob);
                invert_m4_m4(data->invmat, workob.obmat);
        }
        else
                unit_m4(data->invmat);
                
        WM_event_add_notifier(C, NC_OBJECT|ND_CONSTRAINT, ob);
                
        return OPERATOR_FINISHED;
}

static int childof_set_inverse_invoke(bContext *C, wmOperator *op, wmEvent *UNUSED(event))
{
        if (edit_constraint_invoke_properties(C, op))
                return childof_set_inverse_exec(C, op);
        else
                return OPERATOR_CANCELLED;
}

void CONSTRAINT_OT_childof_set_inverse (wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Set Inverse";
        ot->idname= "CONSTRAINT_OT_childof_set_inverse";
        ot->description= "Set inverse correction for ChildOf constraint";
        
        ot->exec= childof_set_inverse_exec;
        ot->invoke= childof_set_inverse_invoke;
        ot->poll= edit_constraint_poll;
        
        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
        edit_constraint_properties(ot);
}

/* ChildOf Constraint - clear inverse callback */
static int childof_clear_inverse_exec (bContext *C, wmOperator *op)
{
        Object *ob = ED_object_active_context(C);
        bConstraint *con = edit_constraint_property_get(op, ob, CONSTRAINT_TYPE_CHILDOF);
        bChildOfConstraint *data= (con) ? (bChildOfConstraint *)con->data : NULL;
        
        if(data==NULL) {
                BKE_report(op->reports, RPT_ERROR, "Childof constraint not found.");
                return OPERATOR_CANCELLED;
        }
        
        /* simply clear the matrix */
        unit_m4(data->invmat);
        
        WM_event_add_notifier(C, NC_OBJECT|ND_CONSTRAINT, ob);
        
        return OPERATOR_FINISHED;
}

static int childof_clear_inverse_invoke(bContext *C, wmOperator *op, wmEvent *UNUSED(event))
{
        if (edit_constraint_invoke_properties(C, op))
                return childof_clear_inverse_exec(C, op);
        else
                return OPERATOR_CANCELLED;
}

void CONSTRAINT_OT_childof_clear_inverse (wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Clear Inverse";
        ot->idname= "CONSTRAINT_OT_childof_clear_inverse";
        ot->description= "Clear inverse correction for ChildOf constraint";
        
        ot->exec= childof_clear_inverse_exec;
        ot->invoke= childof_clear_inverse_invoke;
        ot->poll= edit_constraint_poll;
        
        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
        edit_constraint_properties(ot);
}

/***************************** BUTTONS ****************************/

void ED_object_constraint_set_active(Object *ob, bConstraint *con)
{       
        ListBase *lb = get_constraint_lb(ob, con, NULL);
        
        /* lets be nice and escape if its active already */
        // NOTE: this assumes that the stack doesn't have other active ones set...
        if ((lb && con) && (con->flag & CONSTRAINT_ACTIVE))
                return;
        
        constraints_set_active(lb, con);
}

void ED_object_constraint_update(Object *ob)
{

        if(ob->pose) update_pose_constraint_flags(ob->pose);

        object_test_constraints(ob);

        if(ob->type==OB_ARMATURE) DAG_id_tag_update(&ob->id, OB_RECALC_DATA|OB_RECALC_OB);
        else DAG_id_tag_update(&ob->id, OB_RECALC_OB);
}

void ED_object_constraint_dependency_update(Main *bmain, Scene *scene, Object *ob)
{
        ED_object_constraint_update(ob);

        if(ob->pose) ob->pose->flag |= POSE_RECALC;     // checks & sorts pose channels
        DAG_scene_sort(bmain, scene);
}

static int constraint_poll(bContext *C)
{
        PointerRNA ptr= CTX_data_pointer_get_type(C, "constraint", &RNA_Constraint);
        return (ptr.id.data && ptr.data);
}

static int constraint_delete_exec (bContext *C, wmOperator *UNUSED(op))
{
        PointerRNA ptr= CTX_data_pointer_get_type(C, "constraint", &RNA_Constraint);
        Object *ob= ptr.id.data;
        bConstraint *con= ptr.data;
        ListBase *lb = get_constraint_lb(ob, con, NULL);
        const short is_ik= ELEM(con->type, CONSTRAINT_TYPE_KINEMATIC, CONSTRAINT_TYPE_SPLINEIK);

        /* free the constraint */
        if (remove_constraint(lb, con)) {
                /* there's no active constraint now, so make sure this is the case */
                constraints_set_active(lb, NULL);
                
                ED_object_constraint_update(ob); /* needed to set the flags on posebones correctly */

                /* ITASC needs to be rebuilt once a constraint is removed [#26920] */
                if(is_ik) {
                        BIK_clear_data(ob->pose);
                }

                /* notifiers */
                WM_event_add_notifier(C, NC_OBJECT|ND_CONSTRAINT|NA_REMOVED, ob);
                
                return OPERATOR_FINISHED;
        }
        else {
                /* couldn't remove due to some invalid data */
                return OPERATOR_CANCELLED;
        }
}

void CONSTRAINT_OT_delete (wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Delete Constraint";
        ot->idname= "CONSTRAINT_OT_delete";
        ot->description= "Remove constraint from constraint stack";
        
        /* callbacks */
        ot->exec= constraint_delete_exec;
        ot->poll= constraint_poll;
        
        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO; 
}

static int constraint_move_down_exec (bContext *C, wmOperator *op)
{
        Object *ob = ED_object_active_context(C);
        bConstraint *con = edit_constraint_property_get(op, ob, 0);
        
        if (con && con->next) {
                ListBase *conlist= get_constraint_lb(ob, con, NULL);
                bConstraint *nextCon= con->next;
                
                /* insert the nominated constraint after the one that used to be after it */
                BLI_remlink(conlist, con);
                BLI_insertlinkafter(conlist, nextCon, con);
                
                WM_event_add_notifier(C, NC_OBJECT|ND_CONSTRAINT, ob);
                
                return OPERATOR_FINISHED;
        }
        
        return OPERATOR_CANCELLED;
}

static int constraint_move_down_invoke(bContext *C, wmOperator *op, wmEvent *UNUSED(event))
{
        if (edit_constraint_invoke_properties(C, op))
                return constraint_move_down_exec(C, op);
        else
                return OPERATOR_CANCELLED;
}


void CONSTRAINT_OT_move_down (wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Move Constraint Down";
        ot->idname= "CONSTRAINT_OT_move_down";
        ot->description= "Move constraint down in constraint stack";
        
        /* callbacks */
        ot->exec= constraint_move_down_exec;
        ot->invoke= constraint_move_down_invoke;
        ot->poll= edit_constraint_poll;
        
        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO; 
        edit_constraint_properties(ot);
}


static int constraint_move_up_exec (bContext *C, wmOperator *op)
{
        Object *ob = ED_object_active_context(C);
        bConstraint *con = edit_constraint_property_get(op, ob, 0);
        
        if (con && con->prev) {
                ListBase *conlist= get_constraint_lb(ob, con, NULL);
                bConstraint *prevCon= con->prev;
                
                /* insert the nominated constraint before the one that used to be before it */
                BLI_remlink(conlist, con);
                BLI_insertlinkbefore(conlist, prevCon, con);
                
                WM_event_add_notifier(C, NC_OBJECT|ND_CONSTRAINT, ob);
                
                return OPERATOR_FINISHED;
        }
        
        return OPERATOR_CANCELLED;
}

static int constraint_move_up_invoke(bContext *C, wmOperator *op, wmEvent *UNUSED(event))
{
        if (edit_constraint_invoke_properties(C, op))
                return constraint_move_up_exec(C, op);
        else
                return OPERATOR_CANCELLED;
}

void CONSTRAINT_OT_move_up (wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Move Constraint Up";
        ot->idname= "CONSTRAINT_OT_move_up";
        ot->description= "Move constraint up in constraint stack";
        
        /* callbacks */
        ot->exec= constraint_move_up_exec;
        ot->invoke= constraint_move_up_invoke;
        ot->poll= edit_constraint_poll;
        
        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO; 
        edit_constraint_properties(ot);
}

/***************************** OPERATORS ****************************/

/************************ remove constraint operators *********************/

static int pose_constraints_clear_exec(bContext *C, wmOperator *UNUSED(op))
{
        Main *bmain= CTX_data_main(C);
        Scene *scene= CTX_data_scene(C);
        Object *ob= ED_object_pose_armature(CTX_data_active_object(C));
        
        /* free constraints for all selected bones */
        CTX_DATA_BEGIN(C, bPoseChannel*, pchan, selected_pose_bones)
        {
                free_constraints(&pchan->constraints);
                pchan->constflag &= ~(PCHAN_HAS_IK|PCHAN_HAS_SPLINEIK|PCHAN_HAS_CONST);
        }
        CTX_DATA_END;
        
        /* force depsgraph to get recalculated since relationships removed */
        DAG_scene_sort(bmain, scene);           /* sort order of objects */     
        
        /* note, calling BIK_clear_data() isnt needed here */

        /* do updates */
        DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
        WM_event_add_notifier(C, NC_OBJECT|ND_CONSTRAINT, ob);
        
        return OPERATOR_FINISHED;
}

void POSE_OT_constraints_clear(wmOperatorType *ot)
{
        /* identifiers */
        ot->name = "Clear Pose Constraints";
        ot->idname= "POSE_OT_constraints_clear";
        ot->description= "Clear all the constraints for the selected bones";
        
        /* callbacks */
        ot->exec= pose_constraints_clear_exec;
        ot->poll= ED_operator_posemode; // XXX - do we want to ensure there are selected bones too?
}


static int object_constraints_clear_exec(bContext *C, wmOperator *UNUSED(op))
{
        Main *bmain= CTX_data_main(C);
        Scene *scene= CTX_data_scene(C);
        
        /* do freeing */
        CTX_DATA_BEGIN(C, Object*, ob, selected_editable_objects) 
        {
                free_constraints(&ob->constraints);
                DAG_id_tag_update(&ob->id, OB_RECALC_OB);
        }
        CTX_DATA_END;
        
        /* force depsgraph to get recalculated since relationships removed */
        DAG_scene_sort(bmain, scene);           /* sort order of objects */     
        
        /* do updates */
        WM_event_add_notifier(C, NC_OBJECT|ND_CONSTRAINT, NULL);
        
        return OPERATOR_FINISHED;
}

void OBJECT_OT_constraints_clear(wmOperatorType *ot)
{
        /* identifiers */
        ot->name = "Clear Object Constraints";
        ot->idname= "OBJECT_OT_constraints_clear";
        ot->description= "Clear all the constraints for the active Object only";
        
        /* callbacks */
        ot->exec= object_constraints_clear_exec;
        ot->poll= ED_operator_object_active_editable;
}

/************************ copy all constraints operators *********************/

static int pose_constraint_copy_exec(bContext *C, wmOperator *op)
{
        Main *bmain= CTX_data_main(C);
        Scene *scene = CTX_data_scene(C);
        bPoseChannel *pchan = CTX_data_active_pose_bone(C);
        
        /* don't do anything if bone doesn't exist or doesn't have any constraints */
        if (ELEM(NULL, pchan, pchan->constraints.first)) {
                BKE_report(op->reports, RPT_ERROR, "No active bone with constraints for copying");
                return OPERATOR_CANCELLED;
        }
        
        /* copy all constraints from active posebone to all selected posebones */
        CTX_DATA_BEGIN(C, bPoseChannel*, chan, selected_pose_bones) 
        {
                /* if we're not handling the object we're copying from, copy all constraints over */
                if (pchan != chan) {
                        copy_constraints(&chan->constraints, &pchan->constraints, TRUE);
                        /* update flags (need to add here, not just copy) */
                        chan->constflag |= pchan->constflag;
                }
        }
        CTX_DATA_END;
        
        /* force depsgraph to get recalculated since new relationships added */
        DAG_scene_sort(bmain, scene);           /* sort order of objects/bones */

        WM_event_add_notifier(C, NC_OBJECT|ND_CONSTRAINT, NULL);
        
        return OPERATOR_FINISHED;
}

void POSE_OT_constraints_copy(wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Copy Constraints to Selected";
        ot->idname= "POSE_OT_constraints_copy";
        ot->description = "Copy constraints to other selected bones.";
        
        /* api callbacks */
        ot->exec= pose_constraint_copy_exec;
        ot->poll= ED_operator_posemode;

        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
}

static int object_constraint_copy_exec(bContext *C, wmOperator *UNUSED(op))
{
        Main *bmain= CTX_data_main(C);
        Scene *scene = CTX_data_scene(C);
        Object *obact = ED_object_active_context(C);
        
        /* copy all constraints from active object to all selected objects */
        CTX_DATA_BEGIN(C, Object*, ob, selected_editable_objects) 
        {
                /* if we're not handling the object we're copying from, copy all constraints over */
                if (obact != ob)
                        copy_constraints(&ob->constraints, &obact->constraints, TRUE);
        }
        CTX_DATA_END;
        
        /* force depsgraph to get recalculated since new relationships added */
        DAG_scene_sort(bmain, scene);           /* sort order of objects */

        return OPERATOR_FINISHED;
}

void OBJECT_OT_constraints_copy(wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Copy Constraints to Selected";
        ot->idname= "OBJECT_OT_constraints_copy";
        ot->description = "Copy constraints to other selected objects.";
        
        /* api callbacks */
        ot->exec= object_constraint_copy_exec;
        ot->poll= ED_operator_object_active_editable;

        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
}

/************************ add constraint operators *********************/

/* get the Object and/or PoseChannel to use as target */
static short get_new_constraint_target(bContext *C, int con_type, Object **tar_ob, bPoseChannel **tar_pchan, short add)
{
        Object *obact= ED_object_active_context(C);
        bPoseChannel *pchanact= get_active_posechannel(obact);
        short only_curve= 0, only_mesh= 0, only_ob= 0;
        short found= 0;
        
        /* clear tar_ob and tar_pchan fields before use 
         *      - assume for now that both always exist...
         */
        *tar_ob= NULL;
        *tar_pchan= NULL;
        
        /* check if constraint type doesn't requires a target
         *      - if so, no need to get any targets 
         */
        switch (con_type) {
                /* no-target constraints --------------------------- */
                        /* null constraint - shouldn't even be added! */
                case CONSTRAINT_TYPE_NULL:
                        /* limit constraints - no targets needed */
                case CONSTRAINT_TYPE_LOCLIMIT:
                case CONSTRAINT_TYPE_ROTLIMIT:
                case CONSTRAINT_TYPE_SIZELIMIT:
                case CONSTRAINT_TYPE_SAMEVOL:
                        return 0;
                        
                /* restricted target-type constraints -------------- */
                /* NOTE: for these, we cannot try to add a target object if no valid ones are found, since that doesn't work */
                        /* curve-based constraints - set the only_curve and only_ob flags */
                case CONSTRAINT_TYPE_CLAMPTO:
                case CONSTRAINT_TYPE_FOLLOWPATH:
                case CONSTRAINT_TYPE_SPLINEIK:
                        only_curve= 1;
                        only_ob= 1;
                        add= 0;
                        break;
                        
                        /* mesh only? */
                case CONSTRAINT_TYPE_SHRINKWRAP:
                        only_mesh= 1;
                        only_ob= 1;
                        add= 0;
                        break;
                        
                        /* object only - add here is ok? */
                case CONSTRAINT_TYPE_RIGIDBODYJOINT:
                        only_ob= 1;
                        break;
        }
        
        /* if the active Object is Armature, and we can search for bones, do so... */
        if ((obact->type == OB_ARMATURE) && (only_ob == 0)) {
                /* search in list of selected Pose-Channels for target */
                CTX_DATA_BEGIN(C, bPoseChannel*, pchan, selected_pose_bones) 
                {
                        /* just use the first one that we encounter, as long as it is not the active one */
                        if (pchan != pchanact) {
                                *tar_ob= obact;
                                *tar_pchan= pchan;
                                found= 1;
                                
                                break;
                        }
                }
                CTX_DATA_END;
        }
        
        /* if not yet found, try selected Objects... */
        if (found == 0) {
                /* search in selected objects context */
                CTX_DATA_BEGIN(C, Object*, ob, selected_objects) 
                {
                        /* just use the first object we encounter (that isn't the active object) 
                         * and which fulfills the criteria for the object-target that we've got 
                         */
                        if ( (ob != obact) &&
                                 ((!only_curve) || (ob->type == OB_CURVE)) && 
                                 ((!only_mesh) || (ob->type == OB_MESH)) )
                        {
                                /* set target */
                                *tar_ob= ob;
                                found= 1;
                                
                                /* perform some special operations on the target */
                                if (only_curve) {
                                        /* Curve-Path option must be enabled for follow-path constraints to be able to work */
                                        Curve *cu= (Curve *)ob->data;
                                        cu->flag |= CU_PATH;
                                }
                                
                                break;
                        }
                }
                CTX_DATA_END;
        }
        
        /* if still not found, add a new empty to act as a target (if allowed) */
        if ((found == 0) && (add)) {
                Scene *scene= CTX_data_scene(C);
                Base *base= BASACT, *newbase=NULL;
                Object *obt;
                
                /* add new target object */
                obt= add_object(scene, OB_EMPTY);
                
                /* set layers OK */
                newbase= BASACT;
                newbase->lay= base->lay;
                obt->lay= newbase->lay;
                
                /* transform cent to global coords for loc */
                if (pchanact) {
                        /* since by default, IK targets the tip of the last bone, use the tip of the active PoseChannel 
                         * if adding a target for an IK Constraint
                         */
                        if (con_type == CONSTRAINT_TYPE_KINEMATIC)
                                mul_v3_m4v3(obt->loc, obact->obmat, pchanact->pose_tail);
                        else
                                mul_v3_m4v3(obt->loc, obact->obmat, pchanact->pose_head);
                }
                else
                        VECCOPY(obt->loc, obact->obmat[3]);
                
                /* restore, add_object sets active */
                BASACT= base;
                base->flag |= SELECT;
                
                /* make our new target the new object */
                *tar_ob= obt;
                found= 1;
        }
        
        /* return whether there's any target */
        return found;
}

/* used by add constraint operators to add the constraint required */
static int constraint_add_exec(bContext *C, wmOperator *op, Object *ob, ListBase *list, int type, short setTarget)
{
        Main *bmain= CTX_data_main(C);
        Scene *scene= CTX_data_scene(C);
        bPoseChannel *pchan;
        bConstraint *con;
        
        if (list == &ob->constraints) {
                pchan= NULL;
        }
        else {
                pchan= get_active_posechannel(ob);
                
                /* ensure not to confuse object/pose adding */
                if (pchan == NULL) {
                        BKE_report(op->reports, RPT_ERROR, "No active pose bone to add a constraint to.");
                        return OPERATOR_CANCELLED;
                }
        }
        /* check if constraint to be added is valid for the given constraints stack */
        if (type == CONSTRAINT_TYPE_NULL) {
                return OPERATOR_CANCELLED;
        }
        if ( (type == CONSTRAINT_TYPE_RIGIDBODYJOINT) && (list != &ob->constraints) ) {
                BKE_report(op->reports, RPT_ERROR, "Rigid Body Joint Constraint can only be added to Objects.");
                return OPERATOR_CANCELLED;
        }
        if ( (type == CONSTRAINT_TYPE_KINEMATIC) && ((!pchan) || (list != &pchan->constraints)) ) {
                BKE_report(op->reports, RPT_ERROR, "IK Constraint can only be added to Bones.");
                return OPERATOR_CANCELLED;
        }
        if ( (type == CONSTRAINT_TYPE_SPLINEIK) && ((!pchan) || (list != &pchan->constraints)) ) {
                BKE_report(op->reports, RPT_ERROR, "Spline IK Constraint can only be added to Bones.");
                return OPERATOR_CANCELLED;
        }
        
        /* create a new constraint of the type requried, and add it to the active/given constraints list */
        if (pchan)
                con = add_pose_constraint(ob, pchan, NULL, type);
        else
                con = add_ob_constraint(ob, NULL, type);
        
        /* get the first selected object/bone, and make that the target
         *      - apart from the buttons-window add buttons, we shouldn't add in this way
         */
        if (setTarget) {
                Object *tar_ob= NULL;
                bPoseChannel *tar_pchan= NULL;
                
                /* get the target objects, adding them as need be */
                if (get_new_constraint_target(C, type, &tar_ob, &tar_pchan, 1)) {
                        /* method of setting target depends on the type of target we've got 
                         *      - by default, just set the first target (distinction here is only for multiple-targetted constraints)
                         */
                        if (tar_pchan)
                                set_constraint_nth_target(con, tar_ob, tar_pchan->name, 0);
                        else
                                set_constraint_nth_target(con, tar_ob, "", 0);
                }
        }
        
        /* do type-specific tweaking to the constraint settings  */
        switch (type) {
                case CONSTRAINT_TYPE_PYTHON: // FIXME: this code is not really valid anymore
                {
#ifdef WITH_PYTHON
                        char *menustr;
                        int scriptint= 0;
                        /* popup a list of usable scripts */
                        menustr = buildmenu_pyconstraints(NULL, &scriptint);
                        // XXX scriptint = pupmenu(menustr);
                        MEM_freeN(menustr);
                        
                        /* only add constraint if a script was chosen */
                        if (scriptint) {
                                /* add constraint */
                                validate_pyconstraint_cb(con->data, &scriptint);
                                
                                /* make sure target allowance is set correctly */
                                BPY_pyconstraint_update(ob, con);
                        }
#endif
                }
                default:
                        break;
        }
        
        /* make sure all settings are valid - similar to above checks, but sometimes can be wrong */
        object_test_constraints(ob);

        if (pchan)
                update_pose_constraint_flags(ob->pose);


        /* force depsgraph to get recalculated since new relationships added */
        DAG_scene_sort(bmain, scene);           /* sort order of objects */
        
        if ((ob->type==OB_ARMATURE) && (pchan)) {
                ob->pose->flag |= POSE_RECALC;  /* sort pose channels */
                DAG_id_tag_update(&ob->id, OB_RECALC_DATA|OB_RECALC_OB);
        }
        else
                DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
        
        /* notifiers for updates */
        WM_event_add_notifier(C, NC_OBJECT|ND_CONSTRAINT|NA_ADDED, ob);
        
        return OPERATOR_FINISHED;
}

/* ------------------ */

/* dummy operator callback */
static int object_constraint_add_exec(bContext *C, wmOperator *op)
{
        Object *ob=ED_object_active_context(C);
        int type= RNA_enum_get(op->ptr, "type");
        short with_targets= 0;
        
        if (!ob) {
                BKE_report(op->reports, RPT_ERROR, "No active object to add constraint to.");
                return OPERATOR_CANCELLED;
        }
                
        /* hack: set constraint targets from selected objects in context is allowed when
         *              operator name included 'with_targets', since the menu doesn't allow multiple properties
         */
        if (strstr(op->idname, "with_targets"))
                with_targets= 1;

        return constraint_add_exec(C, op, ob, &ob->constraints, type, with_targets);
}

/* dummy operator callback */
static int pose_constraint_add_exec(bContext *C, wmOperator *op)
{
        Object *ob= ED_object_pose_armature(ED_object_active_context(C));
        int type= RNA_enum_get(op->ptr, "type");
        short with_targets= 0;
        
        if (!ob) {
                BKE_report(op->reports, RPT_ERROR, "No active object to add constraint to.");
                return OPERATOR_CANCELLED;
        }
                
        /* hack: set constraint targets from selected objects in context is allowed when
         *              operator name included 'with_targets', since the menu doesn't allow multiple properties
         */
        if (strstr(op->idname, "with_targets"))
                with_targets= 1;
        
        return constraint_add_exec(C, op, ob, get_active_constraints(ob), type, with_targets);
}

/* ------------------ */

void OBJECT_OT_constraint_add(wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Add Constraint";
        ot->description = "Add a constraint to the active object";
        ot->idname= "OBJECT_OT_constraint_add";
        
        /* api callbacks */
        ot->invoke= WM_menu_invoke;
        ot->exec= object_constraint_add_exec;
        ot->poll= ED_operator_object_active_editable;
        
        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
        
        /* properties */
        ot->prop= RNA_def_enum(ot->srna, "type", constraint_type_items, 0, "Type", "");
}

void OBJECT_OT_constraint_add_with_targets(wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Add Constraint (with Targets)";
        ot->description = "Add a constraint to the active object, with target (where applicable) set to the selected Objects/Bones";
        ot->idname= "OBJECT_OT_constraint_add_with_targets";
        
        /* api callbacks */
        ot->invoke= WM_menu_invoke;
        ot->exec= object_constraint_add_exec;
        ot->poll= ED_operator_object_active_editable;
        
        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
        
        /* properties */
        ot->prop= RNA_def_enum(ot->srna, "type", constraint_type_items, 0, "Type", "");
}

void POSE_OT_constraint_add(wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Add Constraint";
        ot->description = "Add a constraint to the active bone";
        ot->idname= "POSE_OT_constraint_add";
        
        /* api callbacks */
        ot->invoke= WM_menu_invoke;
        ot->exec= pose_constraint_add_exec;
        ot->poll= ED_operator_posemode;
        
        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
        
        /* properties */
        ot->prop= RNA_def_enum(ot->srna, "type", constraint_type_items, 0, "Type", "");
}

void POSE_OT_constraint_add_with_targets(wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Add Constraint (with Targets)";
        ot->description = "Add a constraint to the active bone, with target (where applicable) set to the selected Objects/Bones";
        ot->idname= "POSE_OT_constraint_add_with_targets";
        
        /* api callbacks */
        ot->invoke= WM_menu_invoke;
        ot->exec= pose_constraint_add_exec;
        ot->poll= ED_operator_posemode;
        
        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
        
        /* properties */
        ot->prop= RNA_def_enum(ot->srna, "type", constraint_type_items, 0, "Type", "");
}

/************************ IK Constraint operators *********************/
/* NOTE: only for Pose-Channels */
// TODO: should these be here, or back in editors/armature/poseobject.c again?

/* present menu with options + validation for targets to use */
static int pose_ik_add_invoke(bContext *C, wmOperator *op, wmEvent *UNUSED(evt))
{
        Object *ob= ED_object_pose_armature(CTX_data_active_object(C));
        bPoseChannel *pchan= get_active_posechannel(ob);
        bConstraint *con= NULL;
        
        uiPopupMenu *pup;
        uiLayout *layout;
        Object *tar_ob= NULL;
        bPoseChannel *tar_pchan= NULL;
        
        /* must have active bone */
        if (ELEM(NULL, ob, pchan)) {
                BKE_report(op->reports, RPT_ERROR, "Must have active bone to add IK Constraint to.");
                return OPERATOR_CANCELLED;
        }
        
        /* bone must not have any constraints already */
        for (con= pchan->constraints.first; con; con= con->next) {
                if (con->type==CONSTRAINT_TYPE_KINEMATIC) break;
        }
        if (con) {
                BKE_report(op->reports, RPT_ERROR, "Bone already has IK Constraint.");
                return OPERATOR_CANCELLED;
        }
        
        /* prepare popup menu to choose targetting options */
        pup= uiPupMenuBegin(C, "Add IK", ICON_NONE);
        layout= uiPupMenuLayout(pup);
        
        /* the type of targets we'll set determines the menu entries to show... */
        if (get_new_constraint_target(C, CONSTRAINT_TYPE_KINEMATIC, &tar_ob, &tar_pchan, 0)) {
                /* bone target, or object target? 
                 *      - the only thing that matters is that we want a target...
                 */
                if (tar_pchan)
                        uiItemBooleanO(layout, "To Active Bone", ICON_NONE, "POSE_OT_ik_add", "with_targets", 1);
                else
                        uiItemBooleanO(layout, "To Active Object", ICON_NONE, "POSE_OT_ik_add", "with_targets", 1);
        }
        else {
                /* we have a choice of adding to a new empty, or not setting any target (targetless IK) */
                uiItemBooleanO(layout, "To New Empty Object", ICON_NONE, "POSE_OT_ik_add", "with_targets", 1);
                uiItemBooleanO(layout, "Without Targets", ICON_NONE, "POSE_OT_ik_add", "with_targets", 0);
        }
        
        /* finish building the menu, and process it (should result in calling self again) */
        uiPupMenuEnd(C, pup);
        
        return OPERATOR_CANCELLED;
}

/* call constraint_add_exec() to add the IK constraint */
static int pose_ik_add_exec(bContext *C, wmOperator *op)
{
        Object *ob= CTX_data_active_object(C);
        int with_targets= RNA_boolean_get(op->ptr, "with_targets");
        
        /* add the constraint - all necessary checks should have been done by the invoke() callback already... */
        return constraint_add_exec(C, op, ob, get_active_constraints(ob), CONSTRAINT_TYPE_KINEMATIC, with_targets);
}

void POSE_OT_ik_add(wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Add IK to Bone";
        ot->description= "Add IK Constraint to the active Bone";
        ot->idname= "POSE_OT_ik_add";
        
        /* api callbacks */
        ot->invoke= pose_ik_add_invoke;
        ot->exec= pose_ik_add_exec;
        ot->poll= ED_operator_posemode;
        
        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
        
        /* properties */
        RNA_def_boolean(ot->srna, "with_targets", 1, "With Targets", "Assign IK Constraint with targets derived from the select bones/objects");
}

/* ------------------ */

/* remove IK constraints from selected bones */
static int pose_ik_clear_exec(bContext *C, wmOperator *UNUSED(op))
{
        Object *ob= ED_object_pose_armature(CTX_data_active_object(C));
        
        /* only remove IK Constraints */
        CTX_DATA_BEGIN(C, bPoseChannel*, pchan, selected_pose_bones) 
        {
                bConstraint *con, *next;
                
                // TODO: should we be checking if these contraints were local before we try and remove them?
                for (con= pchan->constraints.first; con; con= next) {
                        next= con->next;
                        if (con->type==CONSTRAINT_TYPE_KINEMATIC) {
                                remove_constraint(&pchan->constraints, con);
                        }
                }
                pchan->constflag &= ~(PCHAN_HAS_IK|PCHAN_HAS_TARGET);
        }
        CTX_DATA_END;
        
        /* refresh depsgraph */
        DAG_id_tag_update(&ob->id, OB_RECALC_DATA);

        /* note, notifier might evolve */
        WM_event_add_notifier(C, NC_OBJECT|ND_CONSTRAINT|NA_REMOVED, ob);
        
        return OPERATOR_FINISHED;
}

void POSE_OT_ik_clear(wmOperatorType *ot)
{
        /* identifiers */
        ot->name= "Remove IK";
        ot->description= "Remove all IK Constraints from selected bones";
        ot->idname= "POSE_OT_ik_clear";
        
        /* api callbacks */
        ot->exec= pose_ik_clear_exec;
        ot->poll= ED_operator_posemode;
        
        /* flags */
        ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
}