aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
blob: 0afc4372d6ed6c49a7bcd211ef02991becbbb13e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
/*
 * Copyright (c) Contributors, http://opensimulator.org/
 * See CONTRIBUTORS.TXT for a full list of copyright holders.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyrightD
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the OpenSimulator Project nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
using System;
using System.Collections.Generic;
using System.Reflection;
using log4net;
using OMV = OpenMetaverse;
using OpenSim.Framework;
using OpenSim.Region.Physics.Manager;

namespace OpenSim.Region.Physics.BulletSPlugin
{
public sealed class BSCharacter : BSPhysObject
{
    private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
    private static readonly string LogHeader = "[BULLETS CHAR]";

    // private bool _stopped;
    private OMV.Vector3 _size;
    private bool _grabbed;
    private bool _selected;
    private OMV.Vector3 _position;
    private float _mass;
    private float _avatarDensity;
    private float _avatarVolume;
    private OMV.Vector3 _force;
    private OMV.Vector3 _velocity;
    private OMV.Vector3 _torque;
    private float _collisionScore;
    private OMV.Vector3 _acceleration;
    private OMV.Quaternion _orientation;
    private int _physicsActorType;
    private bool _isPhysical;
    private bool _flying;
    private bool _setAlwaysRun;
    private bool _throttleUpdates;
    private bool _floatOnWater;
    private OMV.Vector3 _rotationalVelocity;
    private bool _kinematic;
    private float _buoyancy;

    // The friction and velocity of the avatar is modified depending on whether walking or not.
    private float _currentFriction;         // the friction currently being used (changed by setVelocity).

    private BSVMotor _velocityMotor;

    private OMV.Vector3 _PIDTarget;
    private bool _usePID;
    private float _PIDTau;
    private bool _useHoverPID;
    private float _PIDHoverHeight;
    private PIDHoverType _PIDHoverType;
    private float _PIDHoverTao;

    public BSCharacter(uint localID, String avName, BSScene parent_scene, OMV.Vector3 pos, OMV.Vector3 size, bool isFlying)
            : base(parent_scene, localID, avName, "BSCharacter")
    {
        _physicsActorType = (int)ActorTypes.Agent;
        _position = pos;

        _flying = isFlying;
        _orientation = OMV.Quaternion.Identity;
        _velocity = OMV.Vector3.Zero;
        _buoyancy = ComputeBuoyancyFromFlying(isFlying);
        _currentFriction = BSParam.AvatarStandingFriction;
        _avatarDensity = BSParam.AvatarDensity;

        // Old versions of ScenePresence passed only the height. If width and/or depth are zero,
        //     replace with the default values.
        _size = size;
        if (_size.X == 0f) _size.X = BSParam.AvatarCapsuleDepth;
        if (_size.Y == 0f) _size.Y = BSParam.AvatarCapsuleWidth;

        // The dimensions of the physical capsule are kept in the scale.
        // Physics creates a unit capsule which is scaled by the physics engine.
        Scale = ComputeAvatarScale(_size);
        // set _avatarVolume and _mass based on capsule size, _density and Scale
        ComputeAvatarVolumeAndMass();

        SetupMovementMotor();

        DetailLog("{0},BSCharacter.create,call,size={1},scale={2},density={3},volume={4},mass={5}",
                            LocalID, _size, Scale, _avatarDensity, _avatarVolume, RawMass);

        // do actual creation in taint time
        PhysicsScene.TaintedObject("BSCharacter.create", delegate()
        {
            DetailLog("{0},BSCharacter.create,taint", LocalID);
            // New body and shape into PhysBody and PhysShape
            PhysicsScene.Shapes.GetBodyAndShape(true, PhysicsScene.World, this);

            SetPhysicalProperties();
        });
        return;
    }

    // called when this character is being destroyed and the resources should be released
    public override void Destroy()
    {
        base.Destroy();

        DetailLog("{0},BSCharacter.Destroy", LocalID);
        PhysicsScene.TaintedObject("BSCharacter.destroy", delegate()
        {
            PhysicsScene.Shapes.DereferenceBody(PhysBody, null /* bodyCallback */);
            PhysBody.Clear();
            PhysicsScene.Shapes.DereferenceShape(PhysShape, null /* bodyCallback */);
            PhysShape.Clear();
        });
    }

    private void SetPhysicalProperties()
    {
        PhysicsScene.PE.RemoveObjectFromWorld(PhysicsScene.World, PhysBody);

        ZeroMotion(true);
        ForcePosition = _position;

        // Set the velocity and compute the proper friction
        _velocityMotor.Reset();
        _velocityMotor.SetTarget(_velocity);
        _velocityMotor.SetCurrent(_velocity);
        ForceVelocity = _velocity;

        // This will enable or disable the flying buoyancy of the avatar.
        // Needs to be reset especially when an avatar is recreated after crossing a region boundry.
        Flying = _flying;

        PhysicsScene.PE.SetRestitution(PhysBody, BSParam.AvatarRestitution);
        PhysicsScene.PE.SetMargin(PhysShape, PhysicsScene.Params.collisionMargin);
        PhysicsScene.PE.SetLocalScaling(PhysShape, Scale);
        PhysicsScene.PE.SetContactProcessingThreshold(PhysBody, BSParam.ContactProcessingThreshold);
        if (BSParam.CcdMotionThreshold > 0f)
        {
            PhysicsScene.PE.SetCcdMotionThreshold(PhysBody, BSParam.CcdMotionThreshold);
            PhysicsScene.PE.SetCcdSweptSphereRadius(PhysBody, BSParam.CcdSweptSphereRadius);
        }

        UpdatePhysicalMassProperties(RawMass, false);

        // Make so capsule does not fall over
        PhysicsScene.PE.SetAngularFactorV(PhysBody, OMV.Vector3.Zero);

        PhysicsScene.PE.AddToCollisionFlags(PhysBody, CollisionFlags.CF_CHARACTER_OBJECT);

        PhysicsScene.PE.AddObjectToWorld(PhysicsScene.World, PhysBody);

        // PhysicsScene.PE.ForceActivationState(PhysBody, ActivationState.ACTIVE_TAG);
        PhysicsScene.PE.ForceActivationState(PhysBody, ActivationState.DISABLE_DEACTIVATION);
        PhysicsScene.PE.UpdateSingleAabb(PhysicsScene.World, PhysBody);

        // Do this after the object has been added to the world
        PhysBody.collisionType = CollisionType.Avatar;
        PhysBody.ApplyCollisionMask(PhysicsScene);
    }

    // The avatar's movement is controlled by this motor that speeds up and slows down
    //    the avatar seeking to reach the motor's target speed.
    // This motor runs as a prestep action for the avatar so it will keep the avatar
    //    standing as well as moving. Destruction of the avatar will destroy the pre-step action.
    private void SetupMovementMotor()
    {
        // Infinite decay and timescale values so motor only changes current to target values.
        _velocityMotor = new BSVMotor("BSCharacter.Velocity", 
                                            0.2f,                       // time scale
                                            BSMotor.Infinite,           // decay time scale
                                            BSMotor.InfiniteVector,     // friction timescale
                                            1f                          // efficiency
        );
        // _velocityMotor.PhysicsScene = PhysicsScene; // DEBUG DEBUG so motor will output detail log messages.

        RegisterPreStepAction("BSCharactor.Movement", LocalID, delegate(float timeStep)
        {
            // TODO: Decide if the step parameters should be changed depending on the avatar's
            //     state (flying, colliding, ...). There is code in ODE to do this.

            // COMMENTARY: when the user is making the avatar walk, except for falling, the velocity
            //   specified for the avatar is the one that should be used. For falling, if the avatar
            //   is not flying and is not colliding then it is presumed to be falling and the Z
            //   component is not fooled with (thus allowing gravity to do its thing).
            // When the avatar is standing, though, the user has specified a velocity of zero and
            //   the avatar should be standing. But if the avatar is pushed by something in the world
            //   (raising elevator platform, moving vehicle, ...) the avatar should be allowed to
            //   move. Thus, the velocity cannot be forced to zero. The problem is that small velocity
            //   errors can creap in and the avatar will slowly float off in some direction.
            // So, the problem is that, when an avatar is standing, we cannot tell creaping error
            //   from real pushing.OMV.Vector3.Zero;
            // The code below keeps setting the velocity to zero hoping the world will keep pushing.

            _velocityMotor.Step(timeStep);

            // If we're not supposed to be moving, make sure things are zero.
            if (_velocityMotor.ErrorIsZero() && _velocityMotor.TargetValue == OMV.Vector3.Zero && IsColliding)
            {
                // The avatar shouldn't be moving
                _velocityMotor.Zero();

                // If we are colliding with a stationary object, presume we're standing and don't move around
                if (!ColliderIsMoving)
                {
                    DetailLog("{0},BSCharacter.MoveMotor,collidingWithStationary,zeroingMotion", LocalID);
                    ZeroMotion(true /* inTaintTime */);
                }

                // Standing has more friction on the ground
                if (_currentFriction != BSParam.AvatarStandingFriction)
                {
                    _currentFriction = BSParam.AvatarStandingFriction;
                    PhysicsScene.PE.SetFriction(PhysBody, _currentFriction);
                }
                DetailLog("{0},BSCharacter.MoveMotor,taint,stopping,target={1}", LocalID, _velocityMotor.TargetValue);
            }
            else
            {
                OMV.Vector3 stepVelocity = _velocityMotor.CurrentValue;

                if (_currentFriction != BSParam.AvatarFriction)
                {
                    // Probably starting up walking. Set friction to moving friction.
                    _currentFriction = BSParam.AvatarFriction;
                    PhysicsScene.PE.SetFriction(PhysBody, _currentFriction);
                }

                // If falling, we keep the world's downward vector no matter what the other axis specify.
                if (!Flying && !IsColliding)
                {
                    stepVelocity.Z = _velocity.Z;
                    // DetailLog("{0},BSCharacter.MoveMotor,taint,overrideStepZWithWorldZ,stepVel={1}", LocalID, stepVelocity);
                }

                // 'stepVelocity' is now the speed we'd like the avatar to move in. Turn that into an instantanous force.
                OMV.Vector3 moveForce = (stepVelocity - _velocity) * Mass;

                // Should we check for move force being small and forcing velocity to zero?

                // Add special movement force to allow avatars to walk up stepped surfaces.
                moveForce += WalkUpStairs();

                DetailLog("{0},BSCharacter.MoveMotor,move,stepVel={1},vel={2},mass={3},moveForce={4}", LocalID, stepVelocity, _velocity, Mass, moveForce);
                PhysicsScene.PE.ApplyCentralImpulse(PhysBody, moveForce);
            }
        });
    }

    // Decide of the character is colliding with a low object and compute a force to pop the
    //    avatar up so it has a chance of walking up and over the low object.
    private OMV.Vector3 WalkUpStairs()
    {
        OMV.Vector3 ret = OMV.Vector3.Zero;

        // This test is done if moving forward, not flying and is colliding with something.
        // DetailLog("{0},BSCharacter.WalkUpStairs,IsColliding={1},flying={2},targSpeed={3},collisions={4}",
        //                 LocalID, IsColliding, Flying, TargetSpeed, CollisionsLastTick.Count);
        if (IsColliding && !Flying && TargetSpeed > 0.1f /* && ForwardSpeed < 0.1f */)
        {
            // The range near the character's feet where we will consider stairs
            float nearFeetHeightMin = RawPosition.Z - (Size.Z / 2f) + 0.05f;
            float nearFeetHeightMax = nearFeetHeightMin + BSParam.AvatarStepHeight;

            // Look for a collision point that is near the character's feet and is oriented the same as the charactor is
            foreach (KeyValuePair<uint, ContactPoint> kvp in CollisionsLastTick.m_objCollisionList)
            {
                // Don't care about collisions with the terrain
                if (kvp.Key > PhysicsScene.TerrainManager.HighestTerrainID)
                {
                    OMV.Vector3 touchPosition = kvp.Value.Position;
                    // DetailLog("{0},BSCharacter.WalkUpStairs,min={1},max={2},touch={3}",
                    //                 LocalID, nearFeetHeightMin, nearFeetHeightMax, touchPosition);
                    if (touchPosition.Z >= nearFeetHeightMin && touchPosition.Z <= nearFeetHeightMax)
                    {
                        // This contact is within the 'near the feet' range.
                        // The normal should be our contact point to the object so it is pointing away
                        //    thus the difference between our facing orientation and the normal should be small.
                        OMV.Vector3 directionFacing = OMV.Vector3.UnitX * RawOrientation;
                        OMV.Vector3 touchNormal = OMV.Vector3.Normalize(kvp.Value.SurfaceNormal);
                        float diff = Math.Abs(OMV.Vector3.Distance(directionFacing, touchNormal));
                        if (diff < BSParam.AvatarStepApproachFactor)
                        {
                            // Found the stairs contact point. Push up a little to raise the character.
                            float upForce = (touchPosition.Z - nearFeetHeightMin) * Mass * BSParam.AvatarStepForceFactor;
                            ret = new OMV.Vector3(0f, 0f, upForce);

                            // Also move the avatar up for the new height
                            OMV.Vector3 displacement = new OMV.Vector3(0f, 0f, BSParam.AvatarStepHeight / 2f);
                            ForcePosition = RawPosition + displacement;
                        }
                        DetailLog("{0},BSCharacter.WalkUpStairs,touchPos={1},nearFeetMin={2},faceDir={3},norm={4},diff={5},ret={6}",
                                LocalID, touchPosition, nearFeetHeightMin, directionFacing, touchNormal, diff, ret);
                    }
                }
            }
        }

        return ret;
    }

    public override void RequestPhysicsterseUpdate()
    {
        base.RequestPhysicsterseUpdate();
    }
    // No one calls this method so I don't know what it could possibly mean
    public override bool Stopped { get { return false; } }

    public override OMV.Vector3 Size {
        get
        {
            // Avatar capsule size is kept in the scale parameter.
            return _size;
        }

        set {
            _size = value;
            // Old versions of ScenePresence passed only the height. If width and/or depth are zero,
            //     replace with the default values.
            if (_size.X == 0f) _size.X = BSParam.AvatarCapsuleDepth;
            if (_size.Y == 0f) _size.Y = BSParam.AvatarCapsuleWidth;

            Scale = ComputeAvatarScale(_size);
            ComputeAvatarVolumeAndMass();
            DetailLog("{0},BSCharacter.setSize,call,size={1},scale={2},density={3},volume={4},mass={5}",
                            LocalID, _size, Scale, _avatarDensity, _avatarVolume, RawMass);

            PhysicsScene.TaintedObject("BSCharacter.setSize", delegate()
            {
                if (PhysBody.HasPhysicalBody && PhysShape.HasPhysicalShape)
                {
                    PhysicsScene.PE.SetLocalScaling(PhysShape, Scale);
                    UpdatePhysicalMassProperties(RawMass, true);
                    // Make sure this change appears as a property update event
                    PhysicsScene.PE.PushUpdate(PhysBody);
                }
            });

        }
    }

    public override PrimitiveBaseShape Shape
    {
        set { BaseShape = value; }
    }
    // I want the physics engine to make an avatar capsule
    public override BSPhysicsShapeType PreferredPhysicalShape
    {
        get {return BSPhysicsShapeType.SHAPE_CAPSULE; }
    }

    public override bool Grabbed {
        set { _grabbed = value; }
    }
    public override bool Selected {
        set { _selected = value; }
    }
    public override bool IsSelected
    {
        get { return _selected; }
    }
    public override void CrossingFailure() { return; }
    public override void link(PhysicsActor obj) { return; }
    public override void delink() { return; }

    // Set motion values to zero.
    // Do it to the properties so the values get set in the physics engine.
    // Push the setting of the values to the viewer.
    // Called at taint time!
    public override void ZeroMotion(bool inTaintTime)
    {
        _velocity = OMV.Vector3.Zero;
        _acceleration = OMV.Vector3.Zero;
        _rotationalVelocity = OMV.Vector3.Zero;

        // Zero some other properties directly into the physics engine
        PhysicsScene.TaintedObject(inTaintTime, "BSCharacter.ZeroMotion", delegate()
        {
            if (PhysBody.HasPhysicalBody)
                PhysicsScene.PE.ClearAllForces(PhysBody);
        });
    }
    public override void ZeroAngularMotion(bool inTaintTime)
    {
        _rotationalVelocity = OMV.Vector3.Zero;

        PhysicsScene.TaintedObject(inTaintTime, "BSCharacter.ZeroMotion", delegate()
        {
            if (PhysBody.HasPhysicalBody)
            {
                PhysicsScene.PE.SetInterpolationAngularVelocity(PhysBody, OMV.Vector3.Zero);
                PhysicsScene.PE.SetAngularVelocity(PhysBody, OMV.Vector3.Zero);
                // The next also get rid of applied linear force but the linear velocity is untouched.
                PhysicsScene.PE.ClearForces(PhysBody);
            }
        });
    }


    public override void LockAngularMotion(OMV.Vector3 axis) { return; }

    public override OMV.Vector3 RawPosition
    {
        get { return _position; }
        set { _position = value; }
    }
    public override OMV.Vector3 Position {
        get {
            // Don't refetch the position because this function is called a zillion times
            // _position = PhysicsScene.PE.GetObjectPosition(Scene.World, LocalID);
            return _position;
        }
        set {
            _position = value;

            PhysicsScene.TaintedObject("BSCharacter.setPosition", delegate()
            {
                DetailLog("{0},BSCharacter.SetPosition,taint,pos={1},orient={2}", LocalID, _position, _orientation);
                ForcePosition = _position;
            });
        }
    }
    public override OMV.Vector3 ForcePosition {
        get {
            _position = PhysicsScene.PE.GetPosition(PhysBody);
            return _position;
        }
        set {
            _position = value;
            if (PhysBody.HasPhysicalBody)
            {
                PositionSanityCheck();
                PhysicsScene.PE.SetTranslation(PhysBody, _position, _orientation);
            }
        }
    }


    // Check that the current position is sane and, if not, modify the position to make it so.
    // Check for being below terrain or on water.
    // Returns 'true' of the position was made sane by some action.
    private bool PositionSanityCheck()
    {
        bool ret = false;

        // TODO: check for out of bounds
        if (!PhysicsScene.TerrainManager.IsWithinKnownTerrain(RawPosition))
        {
            // The character is out of the known/simulated area.
            // Upper levels of code will handle the transition to other areas so, for
            //     the time, we just ignore the position.
            return ret;
        }

        // If below the ground, move the avatar up
        float terrainHeight = PhysicsScene.TerrainManager.GetTerrainHeightAtXYZ(RawPosition);
        if (Position.Z < terrainHeight)
        {
            DetailLog("{0},BSCharacter.PositionAdjustUnderGround,call,pos={1},terrain={2}", LocalID, _position, terrainHeight);
            _position.Z = terrainHeight + 2.0f;
            ret = true;
        }
        if ((CurrentCollisionFlags & CollisionFlags.BS_FLOATS_ON_WATER) != 0)
        {
            float waterHeight = PhysicsScene.TerrainManager.GetWaterLevelAtXYZ(_position);
            if (Position.Z < waterHeight)
            {
                _position.Z = waterHeight;
                ret = true;
            }
        }

        return ret;
    }

    // A version of the sanity check that also makes sure a new position value is
    //    pushed back to the physics engine. This routine would be used by anyone
    //    who is not already pushing the value.
    private bool PositionSanityCheck(bool inTaintTime)
    {
        bool ret = false;
        if (PositionSanityCheck())
        {
            // The new position value must be pushed into the physics engine but we can't
            //    just assign to "Position" because of potential call loops.
            PhysicsScene.TaintedObject(inTaintTime, "BSCharacter.PositionSanityCheck", delegate()
            {
                DetailLog("{0},BSCharacter.PositionSanityCheck,taint,pos={1},orient={2}", LocalID, _position, _orientation);
                if (PhysBody.HasPhysicalBody)
                    PhysicsScene.PE.SetTranslation(PhysBody, _position, _orientation);
            });
            ret = true;
        }
        return ret;
    }

    public override float Mass { get { return _mass; } }

    // used when we only want this prim's mass and not the linkset thing
    public override float RawMass { 
        get {return _mass; }
    }
    public override void UpdatePhysicalMassProperties(float physMass, bool inWorld)
    {
        OMV.Vector3 localInertia = PhysicsScene.PE.CalculateLocalInertia(PhysShape, physMass);
        PhysicsScene.PE.SetMassProps(PhysBody, physMass, localInertia);
    }

    public override OMV.Vector3 Force {
        get { return _force; }
        set {
            _force = value;
            // m_log.DebugFormat("{0}: Force = {1}", LogHeader, _force);
            PhysicsScene.TaintedObject("BSCharacter.SetForce", delegate()
            {
                DetailLog("{0},BSCharacter.setForce,taint,force={1}", LocalID, _force);
                if (PhysBody.HasPhysicalBody)
                    PhysicsScene.PE.SetObjectForce(PhysBody, _force);
            });
        }
    }

    // Avatars don't do vehicles
    public override int VehicleType { get { return (int)Vehicle.TYPE_NONE; } set { return; } }
    public override void VehicleFloatParam(int param, float value) { }
    public override void VehicleVectorParam(int param, OMV.Vector3 value) {}
    public override void VehicleRotationParam(int param, OMV.Quaternion rotation) { }
    public override void VehicleFlags(int param, bool remove) { }

    // Allows the detection of collisions with inherently non-physical prims. see llVolumeDetect for more
    public override void SetVolumeDetect(int param) { return; }

    public override OMV.Vector3 GeometricCenter { get { return OMV.Vector3.Zero; } }
    public override OMV.Vector3 CenterOfMass { get { return OMV.Vector3.Zero; } }

    // Sets the target in the motor. This starts the changing of the avatar's velocity.
    public override OMV.Vector3 TargetVelocity
    {
        get
        {
            return m_targetVelocity;
        }
        set
        {
            DetailLog("{0},BSCharacter.setTargetVelocity,call,vel={1}", LocalID, value);
            m_targetVelocity = value;
            OMV.Vector3 targetVel = value;
            if (_setAlwaysRun)
                targetVel *= BSParam.AvatarAlwaysRunFactor;

            PhysicsScene.TaintedObject("BSCharacter.setTargetVelocity", delegate()
            {
                _velocityMotor.Reset();
                _velocityMotor.SetTarget(targetVel);
                _velocityMotor.SetCurrent(_velocity);
                _velocityMotor.Enabled = true;
            });
        }
    }
    public override OMV.Vector3 RawVelocity
    {
        get { return _velocity; }
        set { _velocity = value; }
    }
    // Directly setting velocity means this is what the user really wants now.
    public override OMV.Vector3 Velocity {
        get { return _velocity; }
        set {
            _velocity = value;
            // m_log.DebugFormat("{0}: set velocity = {1}", LogHeader, _velocity);
            PhysicsScene.TaintedObject("BSCharacter.setVelocity", delegate()
            {
                _velocityMotor.Reset();
                _velocityMotor.SetCurrent(_velocity);
                _velocityMotor.SetTarget(_velocity);
                _velocityMotor.Enabled = false;

                DetailLog("{0},BSCharacter.setVelocity,taint,vel={1}", LocalID, _velocity);
                ForceVelocity = _velocity;
            });
        }
    }
    public override OMV.Vector3 ForceVelocity {
        get { return _velocity; }
        set {
            PhysicsScene.AssertInTaintTime("BSCharacter.ForceVelocity");

            _velocity = value;
            PhysicsScene.PE.SetLinearVelocity(PhysBody, _velocity);
            PhysicsScene.PE.Activate(PhysBody, true);
        }
    }
    public override OMV.Vector3 Torque {
        get { return _torque; }
        set { _torque = value;
        }
    }
    public override float CollisionScore {
        get { return _collisionScore; }
        set { _collisionScore = value;
        }
    }
    public override OMV.Vector3 Acceleration {
        get { return _acceleration; }
        set { _acceleration = value; }
    }
    public override OMV.Quaternion RawOrientation
    {
        get { return _orientation; }
        set { _orientation = value; }
    }
    public override OMV.Quaternion Orientation {
        get { return _orientation; }
        set {
            // Orientation is set zillions of times when an avatar is walking. It's like
            //      the viewer doesn't trust us.
            if (_orientation != value)
            {
                _orientation = value;
                PhysicsScene.TaintedObject("BSCharacter.setOrientation", delegate()
                {
                    ForceOrientation = _orientation;
                });
            }
        }
    }
    // Go directly to Bullet to get/set the value.
    public override OMV.Quaternion ForceOrientation
    {
        get
        {
            _orientation = PhysicsScene.PE.GetOrientation(PhysBody);
            return _orientation;
        }
        set
        {
            _orientation = value;
            if (PhysBody.HasPhysicalBody)
            {
                // _position = PhysicsScene.PE.GetPosition(BSBody);
                PhysicsScene.PE.SetTranslation(PhysBody, _position, _orientation);
            }
        }
    }
    public override int PhysicsActorType {
        get { return _physicsActorType; }
        set { _physicsActorType = value;
        }
    }
    public override bool IsPhysical {
        get { return _isPhysical; }
        set { _isPhysical = value;
        }
    }
    public override bool IsSolid {
        get { return true; }
    }
    public override bool IsStatic {
        get { return false; }
    }
    public override bool IsPhysicallyActive {
        get { return true; }
    }
    public override bool Flying {
        get { return _flying; }
        set {
            _flying = value;

            // simulate flying by changing the effect of gravity
            Buoyancy = ComputeBuoyancyFromFlying(_flying);
        }
    }
    // Flying is implimented by changing the avatar's buoyancy.
    // Would this be done better with a vehicle type?
    private float ComputeBuoyancyFromFlying(bool ifFlying) {
        return ifFlying ? 1f : 0f;
    }
    public override bool
        SetAlwaysRun {
        get { return _setAlwaysRun; }
        set { _setAlwaysRun = value; }
    }
    public override bool ThrottleUpdates {
        get { return _throttleUpdates; }
        set { _throttleUpdates = value; }
    }
    public override bool FloatOnWater {
        set {
            _floatOnWater = value;
            PhysicsScene.TaintedObject("BSCharacter.setFloatOnWater", delegate()
            {
                if (PhysBody.HasPhysicalBody)
                {
                    if (_floatOnWater)
                        CurrentCollisionFlags = PhysicsScene.PE.AddToCollisionFlags(PhysBody, CollisionFlags.BS_FLOATS_ON_WATER);
                    else
                        CurrentCollisionFlags = PhysicsScene.PE.RemoveFromCollisionFlags(PhysBody, CollisionFlags.BS_FLOATS_ON_WATER);
                }
            });
        }
    }
    public override OMV.Vector3 RotationalVelocity {
        get { return _rotationalVelocity; }
        set { _rotationalVelocity = value; }
    }
    public override OMV.Vector3 ForceRotationalVelocity {
        get { return _rotationalVelocity; }
        set { _rotationalVelocity = value; }
    }
    public override bool Kinematic {
        get { return _kinematic; }
        set { _kinematic = value; }
    }
    // neg=fall quickly, 0=1g, 1=0g, pos=float up
    public override float Buoyancy {
        get { return _buoyancy; }
        set { _buoyancy = value;
            PhysicsScene.TaintedObject("BSCharacter.setBuoyancy", delegate()
            {
                DetailLog("{0},BSCharacter.setBuoyancy,taint,buoy={1}", LocalID, _buoyancy);
                ForceBuoyancy = _buoyancy;
            });
        }
    }
    public override float ForceBuoyancy {
        get { return _buoyancy; }
        set { 
            PhysicsScene.AssertInTaintTime("BSCharacter.ForceBuoyancy");

            _buoyancy = value;
            DetailLog("{0},BSCharacter.setForceBuoyancy,taint,buoy={1}", LocalID, _buoyancy);
            // Buoyancy is faked by changing the gravity applied to the object
            float  grav = BSParam.Gravity * (1f - _buoyancy);
            Gravity = new OMV.Vector3(0f, 0f, grav);
            if (PhysBody.HasPhysicalBody)
                PhysicsScene.PE.SetGravity(PhysBody, Gravity);
        }
    }

    // Used for MoveTo
    public override OMV.Vector3 PIDTarget {
        set { _PIDTarget = value; }
    }
    public override bool PIDActive {
        set { _usePID = value; }
    }
    public override float PIDTau {
        set { _PIDTau = value; }
    }

    // Used for llSetHoverHeight and maybe vehicle height
    // Hover Height will override MoveTo target's Z
    public override bool PIDHoverActive {
        set { _useHoverPID = value; }
    }
    public override float PIDHoverHeight {
        set { _PIDHoverHeight = value; }
    }
    public override PIDHoverType PIDHoverType {
        set { _PIDHoverType = value; }
    }
    public override float PIDHoverTau {
        set { _PIDHoverTao = value; }
    }

    // For RotLookAt
    public override OMV.Quaternion APIDTarget { set { return; } }
    public override bool APIDActive { set { return; } }
    public override float APIDStrength { set { return; } }
    public override float APIDDamping { set { return; } }

    public override void AddForce(OMV.Vector3 force, bool pushforce)
    {
        // Since this force is being applied in only one step, make this a force per second.
        OMV.Vector3 addForce = force / PhysicsScene.LastTimeStep;
        AddForce(addForce, pushforce, false);
    }
    private void AddForce(OMV.Vector3 force, bool pushforce, bool inTaintTime) {
        if (force.IsFinite())
        {
            float magnitude = force.Length();
            if (magnitude > BSParam.MaxAddForceMagnitude)
            {
                // Force has a limit
                force = force / magnitude * BSParam.MaxAddForceMagnitude;
            }

            OMV.Vector3 addForce = force;
            // DetailLog("{0},BSCharacter.addForce,call,force={1}", LocalID, addForce);

            PhysicsScene.TaintedObject(inTaintTime, "BSCharacter.AddForce", delegate()
            {
                // Bullet adds this central force to the total force for this tick
                // DetailLog("{0},BSCharacter.addForce,taint,force={1}", LocalID, addForce);
                if (PhysBody.HasPhysicalBody)
                {
                    PhysicsScene.PE.ApplyCentralForce(PhysBody, addForce);
                }
            });
        }
        else
        {
            m_log.WarnFormat("{0}: Got a NaN force applied to a character. LocalID={1}", LogHeader, LocalID);
            return;
        }
    }

    public override void AddAngularForce(OMV.Vector3 force, bool pushforce) {
    }
    public override void SetMomentum(OMV.Vector3 momentum) {
    }

    private OMV.Vector3 ComputeAvatarScale(OMV.Vector3 size)
    {
        OMV.Vector3 newScale;
        
        // Bullet's capsule total height is the "passed height + radius * 2";
        // The base capsule is 1 diameter and 2 height (passed radius=0.5, passed height = 1)
        // The number we pass in for 'scaling' is the multiplier to get that base
        //     shape to be the size desired.
        // So, when creating the scale for the avatar height, we take the passed height
        //     (size.Z) and remove the caps.
        // Another oddity of the Bullet capsule implementation is that it presumes the Y
        //     dimension is the radius of the capsule. Even though some of the code allows
        //     for a asymmetrical capsule, other parts of the code presume it is cylindrical.

        // Scale is multiplier of radius with one of "0.5"
        newScale.X = size.X / 2f;
        newScale.Y = size.Y / 2f;

        // The total scale height is the central cylindar plus the caps on the two ends.
        newScale.Z = (size.Z + (Math.Min(size.X, size.Y) * 2)) / 2f;
        // If smaller than the endcaps, just fake like we're almost that small
        if (newScale.Z < 0)
            newScale.Z = 0.1f;

        return newScale;
    }

    // set _avatarVolume and _mass based on capsule size, _density and Scale
    private void ComputeAvatarVolumeAndMass()
    {
        _avatarVolume = (float)(
                        Math.PI
                        * Size.X / 2f
                        * Size.Y / 2f    // the area of capsule cylinder
                        * Size.Z         // times height of capsule cylinder
                      + 1.33333333f
                        * Math.PI
                        * Size.X / 2f
                        * Math.Min(Size.X, Size.Y) / 2
                        * Size.Y / 2f    // plus the volume of the capsule end caps
                        );
        _mass = _avatarDensity * _avatarVolume;
    }

    // The physics engine says that properties have updated. Update same and inform
    // the world that things have changed.
    public override void UpdateProperties(EntityProperties entprop)
    {
        _position = entprop.Position;
        _orientation = entprop.Rotation;

        // Smooth velocity. OpenSimulator is VERY sensitive to changes in velocity of the avatar
        //    and will send agent updates to the clients if velocity changes by more than
        //    0.001m/s. Bullet introduces a lot of jitter in the velocity which causes many
        //    extra updates.
        if (!entprop.Velocity.ApproxEquals(_velocity, 0.1f))
            _velocity = entprop.Velocity;

        _acceleration = entprop.Acceleration;
        _rotationalVelocity = entprop.RotationalVelocity;

        // Do some sanity checking for the avatar. Make sure it's above ground and inbounds.
        if (PositionSanityCheck(true))
        {
            entprop.Position = _position;
        }

        // remember the current and last set values
        LastEntityProperties = CurrentEntityProperties;
        CurrentEntityProperties = entprop;

        // Tell the linkset about value changes
        // Linkset.UpdateProperties(UpdatedProperties.EntPropUpdates, this);

        // Avatars don't report their changes the usual way. Changes are checked for in the heartbeat loop.
        // base.RequestPhysicsterseUpdate();

        DetailLog("{0},BSCharacter.UpdateProperties,call,pos={1},orient={2},vel={3},accel={4},rotVel={5}",
                LocalID, _position, _orientation, _velocity, _acceleration, _rotationalVelocity);
    }
}
}