1/*
2 * Copyright (c) 2009-2010 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 com.jme3.util;
33
34import com.jme3.collision.bih.BIHNode.BIHStackData;
35import com.jme3.math.*;
36import com.jme3.scene.Spatial;
37import java.nio.FloatBuffer;
38import java.nio.IntBuffer;
39import java.util.ArrayList;
40
41/**
42 * Temporary variables assigned to each thread. Engine classes may access
43 * these temp variables with TempVars.get(), all retrieved TempVars
44 * instances must be returned via TempVars.release().
45 * This returns an available instance of the TempVar class ensuring this
46 * particular instance is never used elsewhere in the mean time.
47 */
48public class TempVars {
49
50    /**
51     * Allow X instances of TempVars in a single thread.
52     */
53    private static final int STACK_SIZE = 5;
54
55    /**
56     * <code>TempVarsStack</code> contains a stack of TempVars.
57     * Every time TempVars.get() is called, a new entry is added to the stack,
58     * and the index incremented.
59     * When TempVars.release() is called, the entry is checked against
60     * the current instance and  then the index is decremented.
61     */
62    private static class TempVarsStack {
63
64        int index = 0;
65        TempVars[] tempVars = new TempVars[STACK_SIZE];
66    }
67    /**
68     * ThreadLocal to store a TempVarsStack for each thread.
69     * This ensures each thread has a single TempVarsStack that is
70     * used only in method calls in that thread.
71     */
72    private static final ThreadLocal<TempVarsStack> varsLocal = new ThreadLocal<TempVarsStack>() {
73
74        @Override
75        public TempVarsStack initialValue() {
76            return new TempVarsStack();
77        }
78    };
79    /**
80     * This instance of TempVars has been retrieved but not released yet.
81     */
82    private boolean isUsed = false;
83
84    private TempVars() {
85    }
86
87    /**
88     * Acquire an instance of the TempVar class.
89     * You have to release the instance after use by calling the
90     * release() method.
91     * If more than STACK_SIZE (currently 5) instances are requested
92     * in a single thread then an ArrayIndexOutOfBoundsException will be thrown.
93     *
94     * @return A TempVar instance
95     */
96    public static TempVars get() {
97        TempVarsStack stack = varsLocal.get();
98
99        TempVars instance = stack.tempVars[stack.index];
100
101        if (instance == null) {
102            // Create new
103            instance = new TempVars();
104
105            // Put it in there
106            stack.tempVars[stack.index] = instance;
107        }
108
109        stack.index++;
110
111        instance.isUsed = true;
112
113        return instance;
114    }
115
116    /**
117     * Releases this instance of TempVars.
118     * Once released, the contents of the TempVars are undefined.
119     * The TempVars must be released in the opposite order that they are retrieved,
120     * e.g. Acquiring vars1, then acquiring vars2, vars2 MUST be released
121     * first otherwise an exception will be thrown.
122     */
123    public void release() {
124        if (!isUsed) {
125            throw new IllegalStateException("This instance of TempVars was already released!");
126        }
127
128        isUsed = false;
129
130        TempVarsStack stack = varsLocal.get();
131
132        // Return it to the stack
133        stack.index--;
134
135        // Check if it is actually there
136        if (stack.tempVars[stack.index] != this) {
137            throw new IllegalStateException("An instance of TempVars has not been released in a called method!");
138        }
139    }
140    /**
141     * For interfacing with OpenGL in Renderer.
142     */
143    public final IntBuffer intBuffer1 = BufferUtils.createIntBuffer(1);
144    public final IntBuffer intBuffer16 = BufferUtils.createIntBuffer(16);
145    public final FloatBuffer floatBuffer16 = BufferUtils.createFloatBuffer(16);
146    /**
147     * Skinning buffers
148     */
149    public final float[] skinPositions = new float[512 * 3];
150    public final float[] skinNormals = new float[512 * 3];
151     //tangent buffer as 4 components by elements
152    public final float[] skinTangents = new float[512 * 4];
153    /**
154     * Fetching triangle from mesh
155     */
156    public final Triangle triangle = new Triangle();
157    /**
158     * Color
159     */
160    public final ColorRGBA color = new ColorRGBA();
161    /**
162     * General vectors.
163     */
164    public final Vector3f vect1 = new Vector3f();
165    public final Vector3f vect2 = new Vector3f();
166    public final Vector3f vect3 = new Vector3f();
167    public final Vector3f vect4 = new Vector3f();
168    public final Vector3f vect5 = new Vector3f();
169    public final Vector3f vect6 = new Vector3f();
170    public final Vector3f vect7 = new Vector3f();
171    //seems the maximum number of vector used is 7 in com.jme3.bounding.java
172    public final Vector3f vect8 = new Vector3f();
173    public final Vector3f vect9 = new Vector3f();
174    public final Vector3f vect10 = new Vector3f();
175    public final Vector4f vect4f = new Vector4f();
176    public final Vector3f[] tri = {new Vector3f(),
177        new Vector3f(),
178        new Vector3f()};
179    /**
180     * 2D vector
181     */
182    public final Vector2f vect2d = new Vector2f();
183    public final Vector2f vect2d2 = new Vector2f();
184    /**
185     * General matrices.
186     */
187    public final Matrix3f tempMat3 = new Matrix3f();
188    public final Matrix4f tempMat4 = new Matrix4f();
189    public final Matrix4f tempMat42 = new Matrix4f();
190    /**
191     * General quaternions.
192     */
193    public final Quaternion quat1 = new Quaternion();
194    public final Quaternion quat2 = new Quaternion();
195    /**
196     * Eigen
197     */
198    public final Eigen3f eigen = new Eigen3f();
199    /**
200     * Plane
201     */
202    public final Plane plane = new Plane();
203    /**
204     * BoundingBox ray collision
205     */
206    public final float[] fWdU = new float[3];
207    public final float[] fAWdU = new float[3];
208    public final float[] fDdU = new float[3];
209    public final float[] fADdU = new float[3];
210    public final float[] fAWxDdU = new float[3];
211    /**
212     * Maximum tree depth .. 32 levels??
213     */
214    public final Spatial[] spatialStack = new Spatial[32];
215    public final float[] matrixWrite = new float[16];
216    /**
217     * BIHTree
218     */
219    public final float[] bihSwapTmp = new float[9];
220    public final ArrayList<BIHStackData> bihStack = new ArrayList<BIHStackData>();
221}
222