1 // matmodel.cxx -- class to handle models tied to a material property
3 // Written by David Megginson, started May 1998.
5 // Copyright (C) 1998 - 2003 Curtis L. Olson - http://www.flightgear.org/~curt
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
25 # include <simgear_config.h>
28 #include <simgear/compiler.h>
33 #include <osg/AlphaFunc>
36 #include <osg/StateSet>
37 #include <osg/Transform>
39 #include <simgear/debug/logstream.hxx>
40 #include <simgear/math/sg_random.h>
41 #include <simgear/misc/sg_path.hxx>
42 #include <simgear/misc/sgstream.hxx>
43 #include <simgear/scene/model/modellib.hxx>
45 #include "matmodel.hxx"
47 using namespace simgear;
50 ////////////////////////////////////////////////////////////////////////
51 // Implementation of SGMatModel.
52 ////////////////////////////////////////////////////////////////////////
54 SGMatModel::SGMatModel (const SGPropertyNode * node, double range_m)
55 : _models_loaded(false),
56 _coverage_m2(node->getDoubleValue("coverage-m2", 1000000)),
60 if (_coverage_m2 < 1000) {
61 SG_LOG(SG_INPUT, SG_ALERT, "Random object coverage " << _coverage_m2
62 << " is too small, forcing, to 1000");
66 // Note all the model paths
67 vector <SGPropertyNode_ptr> path_nodes = node->getChildren("path");
68 for (unsigned int i = 0; i < path_nodes.size(); i++)
69 _paths.push_back(path_nodes[i]->getStringValue());
71 // Note the heading type
72 string hdg = node->getStringValue("heading-type", "fixed");
74 _heading_type = HEADING_FIXED;
75 } else if (hdg == "billboard") {
76 _heading_type = HEADING_BILLBOARD;
77 } else if (hdg == "random") {
78 _heading_type = HEADING_RANDOM;
80 _heading_type = HEADING_FIXED;
81 SG_LOG(SG_INPUT, SG_ALERT, "Unknown heading type: " << hdg
82 << "; using 'fixed' instead.");
85 // uncomment to preload models
89 SGMatModel::~SGMatModel ()
94 SGMatModel::get_model_count( SGPropertyNode *prop_root )
96 load_models( prop_root );
97 return _models.size();
101 SGMatModel::load_models( SGPropertyNode *prop_root )
103 // Load model only on demand
104 if (!_models_loaded) {
105 for (unsigned int i = 0; i < _paths.size(); i++) {
106 osg::Node *entity = SGModelLib::loadModel(_paths[i], prop_root);
108 // FIXME: this stuff can be handled
109 // in the XML wrapper as well (at least,
110 // the billboarding should be handled
113 if (_heading_type == HEADING_BILLBOARD) {
114 // if the model is a billboard, it is likely :
115 // 1. a branch with only leaves,
116 // 2. a tree or a non rectangular shape faked by transparency
117 // We add alpha clamp then
118 osg::StateSet* stateSet = entity->getOrCreateStateSet();
119 osg::AlphaFunc* alphaFunc =
120 new osg::AlphaFunc(osg::AlphaFunc::GREATER, 0.01f);
121 stateSet->setAttributeAndModes(alphaFunc,
122 osg::StateAttribute::OVERRIDE);
123 stateSet->setRenderingHint(osg::StateSet::TRANSPARENT_BIN);
126 _models.push_back(entity);
129 SG_LOG(SG_INPUT, SG_ALERT, "Failed to load object " << _paths[i]);
133 _models_loaded = true;
137 SGMatModel::get_random_model( SGPropertyNode *prop_root )
139 load_models( prop_root ); // comment this out if preloading models
140 int nModels = _models.size();
141 int index = int(sg_random() * nModels);
142 if (index >= nModels)
144 return _models[index].get();
148 SGMatModel::get_coverage_m2 () const
153 double SGMatModel::get_range_m() const
158 double SGMatModel::get_randomized_range_m(mt* seed) const
160 double lrand = mt_rand(seed);
162 // Note that the LoD is not completely randomized.
163 // 10% at 2 * range_m
164 // 30% at 1.5 * range_m
165 // 60% at 1 * range_m
166 if (lrand < 0.1) return 2 * _range_m;
167 if (lrand < 0.4) return 1.5 * _range_m;
168 else return _range_m;
171 SGMatModel::HeadingType
172 SGMatModel::get_heading_type () const
174 return _heading_type;
179 ////////////////////////////////////////////////////////////////////////
180 // Implementation of SGMatModelGroup.
181 ////////////////////////////////////////////////////////////////////////
183 SGMatModelGroup::SGMatModelGroup (SGPropertyNode * node)
184 : _range_m(node->getDoubleValue("range-m", 2000))
186 // Load the object subnodes
187 vector<SGPropertyNode_ptr> object_nodes =
188 ((SGPropertyNode *)node)->getChildren("object");
189 for (unsigned int i = 0; i < object_nodes.size(); i++) {
190 const SGPropertyNode * object_node = object_nodes[i];
191 if (object_node->hasChild("path"))
192 _objects.push_back(new SGMatModel(object_node, _range_m));
194 SG_LOG(SG_INPUT, SG_ALERT, "No path supplied for object");
198 SGMatModelGroup::~SGMatModelGroup ()
203 SGMatModelGroup::get_range_m () const
209 SGMatModelGroup::get_object_count () const
211 return _objects.size();
215 SGMatModelGroup::get_object (int index) const
217 return _objects[index];
220 // end of matmodel.cxx