aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/OpenSim/Region/PhysicsModules/BulletS/BSActorMoveToTarget.cs
blob: 87cf9729ec3423915bc5ae0f6001d7f3f4d4a976 (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
/*
 * 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.Linq;
using System.Text;

using OpenSim.Region.PhysicsModules.SharedBase;

using OMV = OpenMetaverse;

namespace OpenSim.Region.PhysicsModule.BulletS
{
public class BSActorMoveToTarget : BSActor
{
    private BSVMotor m_targetMotor;

    public BSActorMoveToTarget(BSScene physicsScene, BSPhysObject pObj, string actorName)
        : base(physicsScene, pObj, actorName)
    {
        m_targetMotor = null;
        m_physicsScene.DetailLog("{0},BSActorMoveToTarget,constructor", m_controllingPrim.LocalID);
    }

    // BSActor.isActive
    public override bool isActive
    {
        // MoveToTarget only works on physical prims
        get { return Enabled && m_controllingPrim.IsPhysicallyActive; }
    }

    // Release any connections and resources used by the actor.
    // BSActor.Dispose()
    public override void Dispose()
    {
        Enabled = false;
        DeactivateMoveToTarget();
    }

    // Called when physical parameters (properties set in Bullet) need to be re-applied.
    // Called at taint-time.
    // BSActor.Refresh()
    public override void Refresh()
    {
        m_physicsScene.DetailLog("{0},BSActorMoveToTarget,refresh,enabled={1},active={2},target={3},tau={4}",
            m_controllingPrim.LocalID, Enabled, m_controllingPrim.MoveToTargetActive,
            m_controllingPrim.MoveToTargetTarget, m_controllingPrim.MoveToTargetTau );

        // If not active any more...
        if (!m_controllingPrim.MoveToTargetActive)
        {
            Enabled = false;
        }

        if (isActive)
        {
            ActivateMoveToTarget();
        }
        else
        {
            DeactivateMoveToTarget();
        }
    }

    // The object's physical representation is being rebuilt so pick up any physical dependencies (constraints, ...).
    //     Register a prestep action to restore physical requirements before the next simulation step.
    // Called at taint-time.
    // BSActor.RemoveDependencies()
    public override void RemoveDependencies()
    {
        // Nothing to do for the moveToTarget since it is all software at pre-step action time.
    }

    // If a hover motor has not been created, create one and start the hovering.
    private void ActivateMoveToTarget()
    {
        if (m_targetMotor == null)
        {
            // We're taking over after this.
            m_controllingPrim.ZeroMotion(true);

            /* Someday use the PID controller
            m_targetMotor = new BSPIDVMotor("BSActorMoveToTarget-" + m_controllingPrim.LocalID.ToString());
            m_targetMotor.TimeScale = m_controllingPrim.MoveToTargetTau;
            m_targetMotor.Efficiency = 1f;
             */
            m_targetMotor = new BSVMotor("BSActorMoveToTarget-" + m_controllingPrim.LocalID.ToString(),
                                        m_controllingPrim.MoveToTargetTau,  // timeScale
                                        BSMotor.Infinite,                   // decay time scale
                                        1f                                  // efficiency
            );
            m_targetMotor.PhysicsScene = m_physicsScene; // DEBUG DEBUG so motor will output detail log messages.
            m_targetMotor.SetTarget(m_controllingPrim.MoveToTargetTarget);
            m_targetMotor.SetCurrent(m_controllingPrim.RawPosition);

            // m_physicsScene.BeforeStep += Mover;
            m_physicsScene.BeforeStep += Mover2;
        }
        else
        {
            // If already allocated, make sure the target and other paramters are current
            m_targetMotor.SetTarget(m_controllingPrim.MoveToTargetTarget);
            m_targetMotor.SetCurrent(m_controllingPrim.RawPosition);
        }
    }

    private void DeactivateMoveToTarget()
    {
        if (m_targetMotor != null)
        {
            // m_physicsScene.BeforeStep -= Mover;
            m_physicsScene.BeforeStep -= Mover2;
            m_targetMotor = null;
        }
    }

    // Origional mover that set the objects position to move to the target.
    // The problem was that gravity would keep trying to push the object down so
    //    the overall downward velocity would increase to infinity.
    // Called just before the simulation step.
    private void Mover(float timeStep)
    {
        // Don't do hovering while the object is selected.
        if (!isActive)
            return;

        OMV.Vector3 origPosition = m_controllingPrim.RawPosition;     // DEBUG DEBUG (for printout below)

        // 'movePosition' is where we'd like the prim to be at this moment.
        OMV.Vector3 movePosition = m_controllingPrim.RawPosition + m_targetMotor.Step(timeStep);

        // If we are very close to our target, turn off the movement motor.
        if (m_targetMotor.ErrorIsZero())
        {
            m_physicsScene.DetailLog("{0},BSActorMoveToTarget.Mover,zeroMovement,movePos={1},pos={2},mass={3}",
                                    m_controllingPrim.LocalID, movePosition, m_controllingPrim.RawPosition, m_controllingPrim.Mass);
            m_controllingPrim.ForcePosition = m_targetMotor.TargetValue;
            m_controllingPrim.ForceVelocity = OMV.Vector3.Zero;
            // Setting the position does not cause the physics engine to generate a property update. Force it.
            m_physicsScene.PE.PushUpdate(m_controllingPrim.PhysBody);
        }
        else
        {
            m_controllingPrim.ForcePosition = movePosition;
            // Setting the position does not cause the physics engine to generate a property update. Force it.
            m_physicsScene.PE.PushUpdate(m_controllingPrim.PhysBody);
        }
        m_physicsScene.DetailLog("{0},BSActorMoveToTarget.Mover,move,fromPos={1},movePos={2}",
                                        m_controllingPrim.LocalID, origPosition, movePosition);
    }

    // Version of mover that applies forces to move the physical object to the target.
    // Also overcomes gravity so the object doesn't just drop to the ground.
    // Called just before the simulation step.
    private void Mover2(float timeStep)
    {
        // Don't do hovering while the object is selected.
        if (!isActive)
            return;

        OMV.Vector3 origPosition = m_controllingPrim.RawPosition;     // DEBUG DEBUG (for printout below)
        OMV.Vector3 addedForce = OMV.Vector3.Zero;

        // CorrectionVector is the movement vector required this step
        OMV.Vector3 correctionVector = m_targetMotor.Step(timeStep, m_controllingPrim.RawPosition);

        // If we are very close to our target, turn off the movement motor.
        if (m_targetMotor.ErrorIsZero())
        {
            m_physicsScene.DetailLog("{0},BSActorMoveToTarget.Mover3,zeroMovement,pos={1},mass={2}",
                                    m_controllingPrim.LocalID, m_controllingPrim.RawPosition, m_controllingPrim.Mass);
            m_controllingPrim.ForcePosition = m_targetMotor.TargetValue;
            m_controllingPrim.ForceVelocity = OMV.Vector3.Zero;
            // Setting the position does not cause the physics engine to generate a property update. Force it.
            m_physicsScene.PE.PushUpdate(m_controllingPrim.PhysBody);
        }
        else
        {
            // First force to move us there -- the motor return a timestep scaled value.
            addedForce = correctionVector / timeStep;
            // Remove the existing velocity (only the moveToTarget force counts)
            addedForce -= m_controllingPrim.RawVelocity;
            // Overcome gravity. 
            addedForce -= m_controllingPrim.Gravity;

            // Add enough force to overcome the mass of the object
            addedForce *= m_controllingPrim.Mass;

            m_controllingPrim.AddForce(true /* inTaintTime */, addedForce);
        }
        m_physicsScene.DetailLog("{0},BSActorMoveToTarget.Mover3,move,fromPos={1},addedForce={2}",
                                        m_controllingPrim.LocalID, origPosition, addedForce);
    }
}
}