source: osgVisual/trunk/include/util/TerrainQuery.h @ 298

Last change on this file since 298 was 298, checked in by Torben Dannhauer, 13 years ago
File size: 6.2 KB
Line 
1/* -*-c++-*- osgVisual - Copyright (C) 2009-2011 Torben Dannhauer
2 *
3 * This library is based on OpenSceneGraph, open source and may be redistributed and/or modified under
4 * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
5 * (at your option) any later version.  The full license is in LICENSE file
6 * included with this distribution, and on the openscenegraph.org website.
7 *
8 * osgVisual requires for some proprietary modules a license from the correspondig manufacturer.
9 * You have to aquire licenses for all used proprietary modules.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 * OpenSceneGraph Public License for more details.
15*/
16
17#ifndef OSGSIM_HEIGHTABOVETERRAIN
18#define OSGSIM_HEIGHTABOVETERRAIN 1
19
20#include <osgUtil/IntersectionVisitor>
21
22// include so we can get access to the DatabaseCacheReadCallback
23#include <osgSim/LineOfSight>
24
25namespace osgSim {
26
27/** Helper class for setting up and acquiring height above terrain intersections with terrain.
28  * By default assigns a osgSim::DatabaseCacheReadCallback that enables automatic loading
29  * of external PagedLOD tiles to ensure that the highest level of detail is used in intersections.
30  * This automatic loading of tiles is done by the intersection traversal that is done within
31  * the computeIntersections(..) method, so can result in long intersection times when external
32  * tiles have to be loaded.
33  * The external loading of tiles can be disabled by removing the read callback, this is done by
34  * calling the setDatabaseCacheReadCallback(DatabaseCacheReadCallback*) method with a value of 0.*/
35class OSGSIM_EXPORT HeightAboveTerrain
36{
37    public :
38
39   
40        HeightAboveTerrain(bool loadHighestLOD = true);
41       
42   
43        /** Clear the internal HAT List so it contains no height above terrain tests.*/
44        void clear();
45       
46        /** Add a height above terrain test point in the CoordinateFrame.*/
47        unsigned int addPoint(const osg::Vec3d& point);
48
49        /** Get the number of height above terrain tests.*/
50        unsigned int getNumPoints() const { return _HATList.size(); }
51       
52        /** Set the source point of single height above terrain test.*/
53        void setPoint(unsigned int i, const osg::Vec3d& point) { _HATList[i]._point = point; }
54
55        /** Get the source point of single height above terrain test.*/
56        const osg::Vec3d& getPoint(unsigned int i) const { return _HATList[i]._point; }
57
58        /** Get the intersection height for a single height above terrain test.
59          * Note, you must call computeIntersections(..) before you can query the HeightAboveTerrain.
60          * If no intersections are found then height returned will be the height above mean sea level. */
61        double getHeightAboveTerrain(unsigned int i) const  { return _HATList[i]._hat; }
62
63                /** Get the intersection height for a single height of terrain test.
64          * Note, you must call computeIntersections(..) before you can query the HeightOfTerrain.
65          * If no intersections are found then height returned will be the height of mean sea level. */
66        double getHeightOfTerrain(unsigned int i) const  { return _HATList[i]._hot; }
67
68        /** Set the lowest height that the should be tested for.
69          * Defaults to -1000, i.e. 1000m below mean sea level. */
70        void setLowestHeight(double lowestHeight) { _lowestHeight = lowestHeight; }
71
72        /** Get the lowest height that the should be tested for.*/
73        double getLowestHeight() const { return _lowestHeight; }
74       
75        /** Compute the HAT intersections with the specified scene graph.
76          * The results are all stored in the form of a single height above terrain value per HAT test.
77          * Note, if the topmost node is a CoordinateSystemNode then the input points are assumed to be geocentric,
78          * with the up vector defined by the EllipsoidModel attached to the CoordinateSystemNode.
79          * If the topmost node is not a CoordinateSystemNode then a local coordinates frame is assumed, with a local up vector. */
80        void computeIntersections(osg::Node* scene, osg::Node::NodeMask traversalMask=0xffffffff);
81
82        /** Compute the vertical distance between the specified scene graph and a single HAT point. */
83        static double computeHeightAboveTerrain(osg::Node* scene, const osg::Vec3d& point, bool loadHighestLOD = true, osg::Node::NodeMask traversalMask=0xffffffff);
84       
85                /** Compute the vertical position of the scene at a single HOT point. */
86        static double computeHeightOfTerrain(osg::Node* scene, const osg::Vec3d& point, bool loadHighestLOD = true, osg::Node::NodeMask traversalMask=0xffffffff);
87
88       
89        /** Clear the database cache.*/
90        void clearDatabaseCache() { if (_dcrc.valid()) _dcrc->clearDatabaseCache(); }
91
92        /** Set the ReadCallback that does the reading of external PagedLOD models, and caching of loaded subgraphs.
93          * Note, if you have multiple LineOfSight or HeightAboveTerrain objects in use at one time then you should share a single
94          * DatabaseCacheReadCallback between all of them. */
95        void setDatabaseCacheReadCallback(DatabaseCacheReadCallback* dcrc);
96
97        /** Get the ReadCallback that does the reading of external PagedLOD models, and caching of loaded subgraphs.*/
98        DatabaseCacheReadCallback* getDatabaseCacheReadCallback() { return _dcrc.get(); }
99       
100    protected :
101   
102        struct HAT
103        {
104            HAT(const osg::Vec3d& point):
105                _point(point),
106                _hat(0.0),
107                                _hot(0.0) {}
108               
109            osg::Vec3d      _point;
110            double          _hat;
111                        double          _hot;
112        };
113       
114        typedef std::vector<HAT> HATList;
115       
116
117        double                                  _lowestHeight;
118        HATList                                 _HATList;
119
120       
121        osg::ref_ptr<DatabaseCacheReadCallback> _dcrc;
122        osgUtil::IntersectionVisitor            _intersectionVisitor;
123
124
125};
126
127}
128
129#endif
Note: See TracBrowser for help on using the repository browser.