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 // Local static functions.
52 ////////////////////////////////////////////////////////////////////////
55 * Internal method to test whether a file exists.
57 * TODO: this should be moved to a SimGear library of local file
61 local_file_exists( const string& path ) {
62 sg_gzifstream in( path );
63 if ( ! in.is_open() ) {
72 ////////////////////////////////////////////////////////////////////////
73 // Implementation of SGMatModel.
74 ////////////////////////////////////////////////////////////////////////
76 SGMatModel::SGMatModel (const SGPropertyNode * node, double range_m)
77 : _models_loaded(false),
78 _coverage_m2(node->getDoubleValue("coverage-m2", 1000000)),
82 if (_coverage_m2 < 1000) {
83 SG_LOG(SG_INPUT, SG_ALERT, "Random object coverage " << _coverage_m2
84 << " is too small, forcing, to 1000");
88 // Note all the model paths
89 vector <SGPropertyNode_ptr> path_nodes = node->getChildren("path");
90 for (unsigned int i = 0; i < path_nodes.size(); i++)
91 _paths.push_back(path_nodes[i]->getStringValue());
93 // Note the heading type
94 string hdg = node->getStringValue("heading-type", "fixed");
96 _heading_type = HEADING_FIXED;
97 } else if (hdg == "billboard") {
98 _heading_type = HEADING_BILLBOARD;
99 } else if (hdg == "random") {
100 _heading_type = HEADING_RANDOM;
102 _heading_type = HEADING_FIXED;
103 SG_LOG(SG_INPUT, SG_ALERT, "Unknown heading type: " << hdg
104 << "; using 'fixed' instead.");
107 // uncomment to preload models
111 SGMatModel::~SGMatModel ()
116 SGMatModel::get_model_count( SGPropertyNode *prop_root )
118 load_models( prop_root );
119 return _models.size();
123 SGMatModel::load_models( SGPropertyNode *prop_root )
125 // Load model only on demand
126 if (!_models_loaded) {
127 for (unsigned int i = 0; i < _paths.size(); i++) {
128 osg::Node *entity = SGModelLib::loadModel(_paths[i], prop_root);
130 // FIXME: this stuff can be handled
131 // in the XML wrapper as well (at least,
132 // the billboarding should be handled
135 if (_heading_type == HEADING_BILLBOARD) {
136 // if the model is a billboard, it is likely :
137 // 1. a branch with only leaves,
138 // 2. a tree or a non rectangular shape faked by transparency
139 // We add alpha clamp then
140 osg::StateSet* stateSet = entity->getOrCreateStateSet();
141 osg::AlphaFunc* alphaFunc =
142 new osg::AlphaFunc(osg::AlphaFunc::GREATER, 0.01f);
143 stateSet->setAttributeAndModes(alphaFunc,
144 osg::StateAttribute::OVERRIDE);
145 stateSet->setRenderingHint(osg::StateSet::TRANSPARENT_BIN);
148 _models.push_back(entity);
151 SG_LOG(SG_INPUT, SG_ALERT, "Failed to load object " << _paths[i]);
155 _models_loaded = true;
159 SGMatModel::get_model( int index,
160 SGPropertyNode *prop_root )
162 load_models( prop_root ); // comment this out if preloading models
163 return _models[index].get();
167 SGMatModel::get_random_model( SGPropertyNode *prop_root )
169 load_models( prop_root ); // comment this out if preloading models
170 int nModels = _models.size();
171 int index = int(sg_random() * nModels);
172 if (index >= nModels)
174 return _models[index].get();
178 SGMatModel::get_coverage_m2 () const
183 double SGMatModel::get_range_m() const
188 double SGMatModel::get_randomized_range_m(mt* seed) const
190 double lrand = mt_rand(seed);
192 // Note that the LoD is not completely randomized.
193 // 10% at 2 * range_m
194 // 30% at 1.5 * range_m
195 // 60% at 1 * range_m
196 if (lrand < 0.1) return 2 * _range_m;
197 if (lrand < 0.4) return 1.5 * _range_m;
198 else return _range_m;
201 SGMatModel::HeadingType
202 SGMatModel::get_heading_type () const
204 return _heading_type;
209 ////////////////////////////////////////////////////////////////////////
210 // Implementation of SGMatModelGroup.
211 ////////////////////////////////////////////////////////////////////////
213 SGMatModelGroup::SGMatModelGroup (SGPropertyNode * node)
214 : _range_m(node->getDoubleValue("range-m", 2000))
216 // Load the object subnodes
217 vector<SGPropertyNode_ptr> object_nodes =
218 ((SGPropertyNode *)node)->getChildren("object");
219 for (unsigned int i = 0; i < object_nodes.size(); i++) {
220 const SGPropertyNode * object_node = object_nodes[i];
221 if (object_node->hasChild("path"))
222 _objects.push_back(new SGMatModel(object_node, _range_m));
224 SG_LOG(SG_INPUT, SG_ALERT, "No path supplied for object");
228 SGMatModelGroup::~SGMatModelGroup ()
233 SGMatModelGroup::get_range_m () const
239 SGMatModelGroup::get_object_count () const
241 return _objects.size();
245 SGMatModelGroup::get_object (int index) const
247 return _objects[index];
250 // end of matmodel.cxx