1/*
2 * Copyright (c) 2009-2012 jMonkeyEngine
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met:
8 *
9 * * Redistributions of source code must retain the above copyright
10 *   notice, this list of conditions and the following disclaimer.
11 *
12 * * Redistributions in binary form must reproduce the above copyright
13 *   notice, this list of conditions and the following disclaimer in the
14 *   documentation and/or other materials provided with the distribution.
15 *
16 * * Neither the name of 'jMonkeyEngine' nor the names of its contributors
17 *   may be used to endorse or promote products derived from this software
18 *   without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
24 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
26 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
27 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
28 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
29 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
30 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32package jme3test.bullet;
33
34import com.jme3.bullet.PhysicsSpace;
35import com.jme3.bullet.PhysicsTickListener;
36import com.jme3.bullet.collision.shapes.CollisionShape;
37import com.jme3.bullet.control.PhysicsControl;
38import com.jme3.bullet.objects.PhysicsVehicle;
39import com.jme3.export.InputCapsule;
40import com.jme3.export.JmeExporter;
41import com.jme3.export.JmeImporter;
42import com.jme3.export.OutputCapsule;
43import com.jme3.math.FastMath;
44import com.jme3.math.Vector3f;
45import com.jme3.renderer.RenderManager;
46import com.jme3.renderer.ViewPort;
47import com.jme3.scene.Spatial;
48import com.jme3.scene.control.Control;
49import java.io.IOException;
50
51/**
52 * PhysicsHoverControl uses a RayCast Vehicle with "slippery wheels" to simulate a hovering tank
53 * @author normenhansen
54 */
55public class PhysicsHoverControl extends PhysicsVehicle implements PhysicsControl, PhysicsTickListener {
56
57    protected Spatial spatial;
58    protected boolean enabled = true;
59    protected PhysicsSpace space = null;
60    protected float steeringValue = 0;
61    protected float accelerationValue = 0;
62    protected int xw = 3;
63    protected int zw = 5;
64    protected int yw = 2;
65    protected Vector3f HOVER_HEIGHT_LF_START = new Vector3f(xw, 1, zw);
66    protected Vector3f HOVER_HEIGHT_RF_START = new Vector3f(-xw, 1, zw);
67    protected Vector3f HOVER_HEIGHT_LR_START = new Vector3f(xw, 1, -zw);
68    protected Vector3f HOVER_HEIGHT_RR_START = new Vector3f(-xw, 1, -zw);
69    protected Vector3f HOVER_HEIGHT_LF = new Vector3f(xw, -yw, zw);
70    protected Vector3f HOVER_HEIGHT_RF = new Vector3f(-xw, -yw, zw);
71    protected Vector3f HOVER_HEIGHT_LR = new Vector3f(xw, -yw, -zw);
72    protected Vector3f HOVER_HEIGHT_RR = new Vector3f(-xw, -yw, -zw);
73    protected Vector3f tempVect1 = new Vector3f(0, 0, 0);
74    protected Vector3f tempVect2 = new Vector3f(0, 0, 0);
75    protected Vector3f tempVect3 = new Vector3f(0, 0, 0);
76//    protected float rotationCounterForce = 10000f;
77//    protected float speedCounterMult = 2000f;
78//    protected float multiplier = 1000f;
79
80    public PhysicsHoverControl() {
81    }
82
83    /**
84     * Creates a new PhysicsNode with the supplied collision shape
85     * @param shape
86     */
87    public PhysicsHoverControl(CollisionShape shape) {
88        super(shape);
89        createWheels();
90    }
91
92    public PhysicsHoverControl(CollisionShape shape, float mass) {
93        super(shape, mass);
94        createWheels();
95    }
96
97    public Control cloneForSpatial(Spatial spatial) {
98        throw new UnsupportedOperationException("Not supported yet.");
99    }
100
101    public void setSpatial(Spatial spatial) {
102        this.spatial = spatial;
103        setUserObject(spatial);
104        if (spatial == null) {
105            return;
106        }
107        setPhysicsLocation(spatial.getWorldTranslation());
108        setPhysicsRotation(spatial.getWorldRotation().toRotationMatrix());
109    }
110
111    public void setEnabled(boolean enabled) {
112        this.enabled = enabled;
113    }
114
115    public boolean isEnabled() {
116        return enabled;
117    }
118
119    private void createWheels() {
120        addWheel(HOVER_HEIGHT_LF_START, new Vector3f(0, -1, 0), new Vector3f(-1, 0, 0), yw, yw, false);
121        addWheel(HOVER_HEIGHT_RF_START, new Vector3f(0, -1, 0), new Vector3f(-1, 0, 0), yw, yw, false);
122        addWheel(HOVER_HEIGHT_LR_START, new Vector3f(0, -1, 0), new Vector3f(-1, 0, 0), yw, yw, false);
123        addWheel(HOVER_HEIGHT_RR_START, new Vector3f(0, -1, 0), new Vector3f(-1, 0, 0), yw, yw, false);
124        for (int i = 0; i < 4; i++) {
125            getWheel(i).setFrictionSlip(0.001f);
126        }
127    }
128
129    public void prePhysicsTick(PhysicsSpace space, float f) {
130        Vector3f angVel = getAngularVelocity();
131        float rotationVelocity = angVel.getY();
132        Vector3f dir = getForwardVector(tempVect2).multLocal(1, 0, 1).normalizeLocal();
133        getLinearVelocity(tempVect3);
134        Vector3f linearVelocity = tempVect3.multLocal(1, 0, 1);
135
136        if (steeringValue != 0) {
137            if (rotationVelocity < 1 && rotationVelocity > -1) {
138                applyTorque(tempVect1.set(0, steeringValue, 0));
139            }
140        } else {
141            // counter the steering value!
142            if (rotationVelocity > 0.2f) {
143                applyTorque(tempVect1.set(0, -mass * 20, 0));
144            } else if (rotationVelocity < -0.2f) {
145                applyTorque(tempVect1.set(0, mass * 20, 0));
146            }
147        }
148        if (accelerationValue > 0) {
149            // counter force that will adjust velocity
150            // if we are not going where we want to go.
151            // this will prevent "drifting" and thus improve control
152            // of the vehicle
153            float d = dir.dot(linearVelocity.normalize());
154            Vector3f counter = dir.project(linearVelocity).normalizeLocal().negateLocal().multLocal(1 - d);
155            applyForce(counter.multLocal(mass * 10), Vector3f.ZERO);
156
157            if (linearVelocity.length() < 30) {
158                applyForce(dir.multLocal(accelerationValue), Vector3f.ZERO);
159            }
160        } else {
161            // counter the acceleration value
162            if (linearVelocity.length() > FastMath.ZERO_TOLERANCE) {
163                linearVelocity.normalizeLocal().negateLocal();
164                applyForce(linearVelocity.mult(mass * 10), Vector3f.ZERO);
165            }
166        }
167    }
168
169    public void physicsTick(PhysicsSpace space, float f) {
170    }
171
172    public void update(float tpf) {
173        if (enabled && spatial != null) {
174            getMotionState().applyTransform(spatial);
175        }
176    }
177
178    public void render(RenderManager rm, ViewPort vp) {
179        if (enabled && space != null && space.getDebugManager() != null) {
180            if (debugShape == null) {
181                attachDebugShape(space.getDebugManager());
182            }
183            debugShape.setLocalTranslation(motionState.getWorldLocation());
184            debugShape.setLocalRotation(motionState.getWorldRotation());
185            debugShape.updateLogicalState(0);
186            debugShape.updateGeometricState();
187            rm.renderScene(debugShape, vp);
188        }
189    }
190
191    public void setPhysicsSpace(PhysicsSpace space) {
192        if (space == null) {
193            if (this.space != null) {
194                this.space.removeCollisionObject(this);
195                this.space.removeTickListener(this);
196            }
197            this.space = space;
198        } else {
199            space.addCollisionObject(this);
200            space.addTickListener(this);
201        }
202        this.space = space;
203    }
204
205    public PhysicsSpace getPhysicsSpace() {
206        return space;
207    }
208
209    @Override
210    public void write(JmeExporter ex) throws IOException {
211        super.write(ex);
212        OutputCapsule oc = ex.getCapsule(this);
213        oc.write(enabled, "enabled", true);
214        oc.write(spatial, "spatial", null);
215    }
216
217    @Override
218    public void read(JmeImporter im) throws IOException {
219        super.read(im);
220        InputCapsule ic = im.getCapsule(this);
221        enabled = ic.readBoolean("enabled", true);
222        spatial = (Spatial) ic.readSavable("spatial", null);
223    }
224
225    /**
226     * @param steeringValue the steeringValue to set
227     */
228    @Override
229    public void steer(float steeringValue) {
230        this.steeringValue = steeringValue * getMass();
231    }
232
233    /**
234     * @param accelerationValue the accelerationValue to set
235     */
236    @Override
237    public void accelerate(float accelerationValue) {
238        this.accelerationValue = accelerationValue * getMass();
239    }
240}
241