Added SmokeTrailEffect which renders created particles as single quad or line

strip, in the case of the quad strip the strip is aligned to the be orthogonal with
the eye point.

src/osgParticle/SmokeTrailEffect.cpp

@@ -0,0 +1,149 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2005 Robert Osfield 
+ *
+ * This library is open source and may be redistributed and/or modified under  
+ * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or 
+ * (at your option) any later version.  The full license is in LICENSE file
+ * included with this distribution, and on the openscenegraph.org website.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
+ * OpenSceneGraph Public License for more details.
+*/
+
+#include <osgParticle/SmokeTrailEffect>
+
+#include <osgParticle/ConstantRateCounter>
+#include <osgParticle/RadialShooter>
+#include <osgParticle/SectorPlacer>
+#include <osgParticle/ParticleSystemUpdater>
+#include <osgParticle/ConnectedParticleSystem>
+
+#include <osg/Geode>
+
+using namespace osgParticle;
+
+SmokeTrailEffect::SmokeTrailEffect(const osg::Vec3& position, float scale, float intensity)
+{
+    setDefaults();
+    
+    _position = position;
+    _scale = scale;
+    _intensity = intensity;
+
+    _emitterDuration = 65.0;
+    _defaultParticleTemplate.setLifeTime(5.0*_scale);
+        
+    buildEffect();
+}
+
+SmokeTrailEffect::SmokeTrailEffect(const SmokeTrailEffect& copy, const osg::CopyOp& copyop):
+    ParticleEffect(copy,copyop)
+{
+}
+
+void SmokeTrailEffect::setDefaults()
+{
+    ParticleEffect::setDefaults();
+    
+    _textureFileName = "Images/continous_smoke.rgb";    
+    _emitterDuration = 65.0;
+
+    // set up unit particle.
+    _defaultParticleTemplate.setLifeTime(5.0*_scale);
+    _defaultParticleTemplate.setSizeRange(osgParticle::rangef(0.75f, 2.0f));
+    _defaultParticleTemplate.setAlphaRange(osgParticle::rangef(0.7f, 1.0f));
+    _defaultParticleTemplate.setColorRange(osgParticle::rangev4(
+                                            osg::Vec4(1, 1.0f, 1.0f, 1.0f), 
+                                            osg::Vec4(1, 1.0f, 1.f, 0.0f)));
+
+
+}
+
+void SmokeTrailEffect::setUpEmitterAndProgram()
+{
+    // set up particle system
+    if (!_particleSystem)
+    {
+        _particleSystem = new osgParticle::ConnectedParticleSystem;
+    }
+
+    if (_particleSystem.valid())
+    {
+        _particleSystem->setDefaultAttributes(_textureFileName, false, false);
+
+        osgParticle::Particle& ptemplate = _particleSystem->getDefaultParticleTemplate();
+
+        float radius = 0.5f*_scale; 
+        float density = 1.0f; // 1.0kg/m^3
+
+        ptemplate.setLifeTime(_defaultParticleTemplate.getLifeTime());
+
+        // the following ranges set the envelope of the respective 
+        // graphical properties in time.
+        ptemplate.setSizeRange(osgParticle::rangef(radius*_defaultParticleTemplate.getSizeRange().minimum,
+                                                   radius*_defaultParticleTemplate.getSizeRange().maximum));
+        ptemplate.setAlphaRange(_defaultParticleTemplate.getAlphaRange());
+        ptemplate.setColorRange(_defaultParticleTemplate.getColorRange());
+
+        // these are physical properties of the particle
+        ptemplate.setRadius(radius);
+        ptemplate.setMass(density*radius*radius*radius*osg::PI*4.0f/3.0f);
+
+    }
+
+
+    // set up emitter
+    if (!_emitter)
+    {
+        _emitter = new osgParticle::ModularEmitter;
+        _emitter->setCounter(new osgParticle::ConstantRateCounter);
+        _emitter->setPlacer(new osgParticle::SectorPlacer);
+        _emitter->setShooter(new osgParticle::RadialShooter);
+    }
+
+    if (_emitter.valid())
+    {
+        _emitter->setParticleSystem(_particleSystem.get());
+        _emitter->setReferenceFrame(_useLocalParticleSystem?
+                                    osgParticle::ParticleProcessor::ABSOLUTE_RF:
+                                    osgParticle::ParticleProcessor::RELATIVE_RF);
+
+        _emitter->setStartTime(_startTime);
+        _emitter->setLifeTime(_emitterDuration);
+        _emitter->setEndless(false);
+
+        osgParticle::ConstantRateCounter* counter = dynamic_cast<osgParticle::ConstantRateCounter*>(_emitter->getCounter());
+        if (counter)
+        {
+            counter->setMinimumNumberOfParticlesToCreate(1);
+            counter->setNumberOfParticlesPerSecondToCreate(0.0);
+        }
+
+        osgParticle::SectorPlacer* placer = dynamic_cast<osgParticle::SectorPlacer*>(_emitter->getPlacer());
+        if (placer)
+        {
+            placer->setCenter(_position);
+            placer->setRadiusRange(0.0f*_scale,0.0f*_scale);
+        }
+
+        osgParticle::RadialShooter* shooter = dynamic_cast<osgParticle::RadialShooter*>(_emitter->getShooter());
+        if (shooter)
+        {
+            shooter->setThetaRange(0.0f, 0.0f);
+            shooter->setInitialSpeedRange(0.0f*_scale,0.0f*_scale);
+        }
+    }
+
+    // set up program.
+    if (!_program)
+    {        
+        _program = new osgParticle::FluidProgram;
+    }
+    
+    if (_program.valid())
+    {
+        _program->setParticleSystem(_particleSystem.get());
+        _program->setWind(_wind);
+    }
+}