Added the beginings of new osgParticle Explosion, Fire and SmokeEffects.

Added support for generation explosion, fire and smoke effects in osgsimulation

src/osgParticle/ExplosionEffect.cpp

@@ -0,0 +1,134 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2003 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/ExplosionEffect>
+
+#include <osgParticle/ExplosionEffect>
+#include <osgParticle/ModularEmitter>
+#include <osgParticle/ModularProgram>
+#include <osgParticle/RandomRateCounter>
+#include <osgParticle/SectorPlacer>
+#include <osgParticle/RadialShooter>
+#include <osgParticle/AccelOperator>
+#include <osgParticle/FluidFrictionOperator>
+
+#include <osg/Geode>
+
+using namespace osgParticle;
+
+ExplosionEffect::ExplosionEffect()
+{
+    setDefaults();
+}
+
+ExplosionEffect::ExplosionEffect(const ExplosionEffect& copy, const osg::CopyOp& copyop):
+    ParticleEffect(copy,copyop)
+{
+}
+
+void ExplosionEffect::setDefaults()
+{
+    osgParticle::ParticleSystem *ps = new osgParticle::ParticleSystem;
+    ps->setDefaultAttributes("Images/particle.rgb", false, false);
+    
+    _particleSystem = ps;
+
+    // set up the emitter
+    {
+        osgParticle::ModularEmitter *emitter = new osgParticle::ModularEmitter;
+        emitter->setParticleSystem(ps);
+
+        osgParticle::Particle ptemplate;
+
+        ptemplate.setLifeTime(3);        // 3 seconds of life
+
+        // the following ranges set the envelope of the respective 
+        // graphical properties in time.
+        ptemplate.setSizeRange(osgParticle::rangef(0.75f, 3.0f));
+        ptemplate.setAlphaRange(osgParticle::rangef(0.0f, 1.0f));
+        ptemplate.setColorRange(osgParticle::rangev4(
+            osg::Vec4(1, 1.0f, 0.0f, 1.0f), 
+            osg::Vec4(0.5, 0.5f, 0.0f, 0.0f)));
+
+        // these are physical properties of the particle
+        ptemplate.setRadius(0.1f);    // 5 cm wide particles
+        ptemplate.setMass(1.0f);    // 1kg heavy
+
+        // assign the particle template to the system.
+        ps->setDefaultParticleTemplate(ptemplate);
+
+        //osgParticle::LimitedDurationRandomRateCounter* counter = new osgParticle::LimitedDurationRandomRateCounter;
+        osgParticle::RandomRateCounter* counter = new osgParticle::RandomRateCounter;
+        counter->setRateRange(2000,2000);    // generate 1000 particles per second
+        emitter->setCounter(counter);
+
+        osgParticle::SectorPlacer* placer = new osgParticle::SectorPlacer;
+        placer->setCenter(osg::Vec3(0.0,0.0,0.0));
+        placer->setRadiusRange(0.0f,1.0f);
+        emitter->setPlacer(placer);
+
+        osgParticle::RadialShooter* shooter = new osgParticle::RadialShooter;
+        shooter->setThetaRange(0.0f, osg::PI_2);
+        shooter->setInitialSpeedRange(5.0f,30.0f);
+        emitter->setShooter(shooter);
+        
+        emitter->setStartTime(0.0f);
+        emitter->setResetTime(5.0f);
+        emitter->setLifeTime(0.1f);
+        emitter->setEndless(false);
+
+        _emitter = emitter;
+    }
+
+
+    // set up the program
+    {
+        osgParticle::ModularProgram *program = new osgParticle::ModularProgram;
+        program->setParticleSystem(ps);
+
+        // create an operator that simulates the gravity acceleration.
+        osgParticle::AccelOperator *op1 = new osgParticle::AccelOperator;
+        op1->setToGravity();
+        program->addOperator(op1);
+
+        // let's add a fluid operator to simulate air friction.
+        osgParticle::FluidFrictionOperator *op3 = new osgParticle::FluidFrictionOperator;
+        op3->setFluidToAir();
+        program->addOperator(op3);
+        
+        _program = program;
+    }
+    
+    
+    buildEffect();
+}
+
+void ExplosionEffect::buildEffect()
+{
+    // clear the children.
+    removeChild(0,getNumChildren());
+    
+    if (!_emitter || !_particleSystem || !_program) return; 
+    
+    // add the emitter
+    addChild(_emitter.get());
+    
+    // add the program to update the particles
+    addChild(_program.get());
+
+    osg::Geode *geode = new osg::Geode;
+    geode->addDrawable(_particleSystem.get());
+
+    // add the geode to the scene graph
+    addChild(geode);
+}