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 */
32
33package com.jme3.terrain.geomipmap.lodcalc;
34
35import com.jme3.export.Savable;
36import com.jme3.math.Vector3f;
37import com.jme3.terrain.geomipmap.TerrainPatch;
38import com.jme3.terrain.geomipmap.UpdatedTerrainPatch;
39import java.util.HashMap;
40import java.util.List;
41
42/**
43 * Calculate the Level of Detail of a terrain patch based on the
44 * cameras, or other locations.
45 *
46 * @author Brent Owens
47 */
48public interface LodCalculator extends Savable, Cloneable {
49
50    public boolean calculateLod(TerrainPatch terrainPatch, List<Vector3f> locations, HashMap<String,UpdatedTerrainPatch> updates);
51
52    public LodCalculator clone();
53
54    public void turnOffLod();
55    public void turnOnLod();
56    public boolean isLodOff();
57
58    /**
59     * If true, then this calculator can cause neighbouring terrain chunks to
60     * have LOD levels that are greater than 1 apart.
61     * Entropy algorithms will want to return true for this. Straight distance
62     * calculations will just want to return false.
63     */
64    public boolean usesVariableLod();
65}
66