a3adc3d07c
The texture in data/Images should be copied to osg-data. I created the texture myself with the help of an explosion generator, so no license issues there. "
497 lines
20 KiB
C++
497 lines
20 KiB
C++
/* OpenSceneGraph example, osgparticle.
|
||
*
|
||
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
||
* of this software and associated documentation files (the "Software"), to deal
|
||
* in the Software without restriction, including without limitation the rights
|
||
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||
* copies of the Software, and to permit persons to whom the Software is
|
||
* furnished to do so, subject to the following conditions:
|
||
*
|
||
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
||
* THE SOFTWARE.
|
||
*/
|
||
|
||
#include <osgViewer/Viewer>
|
||
#include <osgViewer/ViewerEventHandlers>
|
||
|
||
#include <osg/Group>
|
||
#include <osg/Geode>
|
||
|
||
#include <osgParticle/Particle>
|
||
#include <osgParticle/ParticleSystem>
|
||
#include <osgParticle/ParticleSystemUpdater>
|
||
#include <osgParticle/ModularEmitter>
|
||
#include <osgParticle/ModularProgram>
|
||
#include <osgParticle/RandomRateCounter>
|
||
#include <osgParticle/SectorPlacer>
|
||
#include <osgParticle/RadialShooter>
|
||
#include <osgParticle/AccelOperator>
|
||
#include <osgParticle/FluidFrictionOperator>
|
||
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////////////
|
||
// CUSTOM OPERATOR CLASS
|
||
//////////////////////////////////////////////////////////////////////////////
|
||
|
||
// This class demonstrates Operator subclassing. This way you can create
|
||
// custom operators to apply your motion effects to the particles. See docs
|
||
// for more details.
|
||
class VortexOperator: public osgParticle::Operator {
|
||
public:
|
||
VortexOperator()
|
||
: osgParticle::Operator(), center_(0, 0, 0), axis_(0, 0, 1), intensity_(0.1f) {}
|
||
|
||
VortexOperator(const VortexOperator ©, const osg::CopyOp ©op = osg::CopyOp::SHALLOW_COPY)
|
||
: osgParticle::Operator(copy, copyop), center_(copy.center_), axis_(copy.axis_), intensity_(copy.intensity_) {}
|
||
|
||
META_Object(osgParticle, VortexOperator);
|
||
|
||
void setCenter(const osg::Vec3 &c)
|
||
{
|
||
center_ = c;
|
||
}
|
||
|
||
void setAxis(const osg::Vec3 &a)
|
||
{
|
||
axis_ = a / a.length();
|
||
}
|
||
|
||
// this method is called by ModularProgram before applying
|
||
// operators on the particle set via the operate() method.
|
||
void beginOperate(osgParticle::Program *prg)
|
||
{
|
||
// we have to check whether the reference frame is RELATIVE_RF to parents
|
||
// or it's absolute; in the first case, we must transform the vectors
|
||
// from local to world space.
|
||
if (prg->getReferenceFrame() == osgParticle::Program::RELATIVE_RF) {
|
||
// transform the center point (full transformation)
|
||
xf_center_ = prg->transformLocalToWorld(center_);
|
||
// transform the axis vector (only rotation and scale)
|
||
xf_axis_ = prg->rotateLocalToWorld(axis_);
|
||
} else {
|
||
xf_center_ = center_;
|
||
xf_axis_ = axis_;
|
||
}
|
||
}
|
||
|
||
// apply a vortex-like acceleration. This code is not optimized,
|
||
// it's here only for demonstration purposes.
|
||
void operate(osgParticle::Particle *P, double dt)
|
||
{
|
||
float l = xf_axis_ * (P->getPosition() - xf_center_);
|
||
osg::Vec3 lc = xf_center_ + xf_axis_ * l;
|
||
osg::Vec3 R = P->getPosition() - lc;
|
||
osg::Vec3 v = (R ^ xf_axis_) * P->getMassInv() * intensity_;
|
||
|
||
// compute new position
|
||
osg::Vec3 newpos = P->getPosition() + v * dt;
|
||
|
||
// update the position of the particle without modifying its
|
||
// velocity vector (this is unusual, normally you should call
|
||
// the Particle::setVelocity() or Particle::addVelocity()
|
||
// methods).
|
||
P->setPosition(newpos);
|
||
}
|
||
|
||
protected:
|
||
virtual ~VortexOperator() {}
|
||
|
||
private:
|
||
osg::Vec3 center_;
|
||
osg::Vec3 xf_center_;
|
||
osg::Vec3 axis_;
|
||
osg::Vec3 xf_axis_;
|
||
float intensity_;
|
||
};
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////////////
|
||
// SIMPLE PARTICLE SYSTEM CREATION
|
||
//////////////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
osgParticle::ParticleSystem *create_simple_particle_system(osg::Group *root)
|
||
{
|
||
|
||
// Ok folks, this is the first particle system we build; it will be
|
||
// very simple, with no textures and no special effects, just default
|
||
// values except for a couple of attributes.
|
||
|
||
// First of all, we create the ParticleSystem object; it will hold
|
||
// our particles and expose the interface for managing them; this object
|
||
// is a Drawable, so we'll have to add it to a Geode later.
|
||
|
||
osgParticle::ParticleSystem *ps = new osgParticle::ParticleSystem;
|
||
|
||
// As for other Drawable classes, the aspect of graphical elements of
|
||
// ParticleSystem (the particles) depends on the StateAttribute's we
|
||
// give it. The ParticleSystem class has an helper function that let
|
||
// us specify a set of the most common attributes: setDefaultAttributes().
|
||
// This method can accept up to three parameters; the first is a texture
|
||
// name (std::string), which can be empty to disable texturing, the second
|
||
// sets whether particles have to be "emissive" (additive blending) or not;
|
||
// the third parameter enables or disables lighting.
|
||
|
||
ps->setDefaultAttributes("", true, false);
|
||
|
||
// Now that our particle system is set we have to create an emitter, that is
|
||
// an object (actually a Node descendant) that generate new particles at
|
||
// each frame. The best choice is to use a ModularEmitter, which allow us to
|
||
// achieve a wide variety of emitting styles by composing the emitter using
|
||
// three objects: a "counter", a "placer" and a "shooter". The counter must
|
||
// tell the ModularEmitter how many particles it has to create for the
|
||
// current frame; then, the ModularEmitter creates these particles, and for
|
||
// each new particle it instructs the placer and the shooter to set its
|
||
// position vector and its velocity vector, respectively.
|
||
// By default, a ModularEmitter object initializes itself with a counter of
|
||
// type RandomRateCounter, a placer of type PointPlacer and a shooter of
|
||
// type RadialShooter (see documentation for details). We are going to leave
|
||
// these default objects there, but we'll modify the counter so that it
|
||
// counts faster (more particles are emitted at each frame).
|
||
|
||
osgParticle::ModularEmitter *emitter = new osgParticle::ModularEmitter;
|
||
|
||
// the first thing you *MUST* do after creating an emitter is to set the
|
||
// destination particle system, otherwise it won't know where to create
|
||
// new particles.
|
||
|
||
emitter->setParticleSystem(ps);
|
||
|
||
// Ok, get a pointer to the emitter's Counter object. We could also
|
||
// create a new RandomRateCounter object and assign it to the emitter,
|
||
// but since the default counter is already a RandomRateCounter, we
|
||
// just get a pointer to it and change a value.
|
||
|
||
osgParticle::RandomRateCounter *rrc =
|
||
static_cast<osgParticle::RandomRateCounter *>(emitter->getCounter());
|
||
|
||
// Now set the rate range to a better value. The actual rate at each frame
|
||
// will be chosen randomly within that range.
|
||
|
||
rrc->setRateRange(20, 30); // generate 20 to 30 particles per second
|
||
|
||
// The emitter is done! Let's add it to the scene graph. The cool thing is
|
||
// that any emitter node will take into account the accumulated local-to-world
|
||
// matrix, so you can attach an emitter to a transform node and see it move.
|
||
|
||
root->addChild(emitter);
|
||
|
||
// Ok folks, we have almost finished. We don't add any particle modifier
|
||
// here (see ModularProgram and Operator classes), so all we still need is
|
||
// to create a Geode and add the particle system to it, so it can be
|
||
// displayed.
|
||
|
||
osg::Geode *geode = new osg::Geode;
|
||
geode->addDrawable(ps);
|
||
|
||
// add the geode to the scene graph
|
||
root->addChild(geode);
|
||
|
||
return ps;
|
||
|
||
}
|
||
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////////////
|
||
// COMPLEX PARTICLE SYSTEM CREATION
|
||
//////////////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
osgParticle::ParticleSystem *create_complex_particle_system(osg::Group *root)
|
||
{
|
||
// Are you ready for a more complex particle system? Well, read on!
|
||
|
||
// Now we take one step we didn't before: create a particle template.
|
||
// A particle template is simply a Particle object for which you set
|
||
// the desired properties (see documentation for details). When the
|
||
// particle system has to create a new particle and it's been assigned
|
||
// a particle template, the new particle will inherit the template's
|
||
// properties.
|
||
// You can even assign different particle templates to each emitter; in
|
||
// this case, the emitter's template will override the particle system's
|
||
// default template.
|
||
|
||
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, 1.5f));
|
||
ptemplate.setColorRange(osgParticle::rangev4(
|
||
osg::Vec4(1, 0.5f, 0.3f, 1.5f),
|
||
osg::Vec4(0, 0.7f, 1.0f, 0.0f)));
|
||
|
||
// these are physical properties of the particle
|
||
ptemplate.setRadius(0.05f); // 5 cm wide particles
|
||
ptemplate.setMass(0.05f); // 50 g heavy
|
||
|
||
// As usual, let's create the ParticleSystem object and set its
|
||
// default state attributes. This time we use a texture named
|
||
// "smoke.rgb", you can find it in the data distribution of OSG.
|
||
// We turn off the additive blending, because smoke has no self-
|
||
// illumination.
|
||
osgParticle::ParticleSystem *ps = new osgParticle::ParticleSystem;
|
||
ps->setDefaultAttributes("Images/smoke.rgb", false, false);
|
||
|
||
// assign the particle template to the system.
|
||
ps->setDefaultParticleTemplate(ptemplate);
|
||
|
||
// now we have to create an emitter; this will be a ModularEmitter, for which
|
||
// we define a RandomRateCounter as counter, a SectorPlacer as placer, and
|
||
// a RadialShooter as shooter.
|
||
osgParticle::ModularEmitter *emitter = new osgParticle::ModularEmitter;
|
||
emitter->setParticleSystem(ps);
|
||
|
||
// setup the counter
|
||
osgParticle::RandomRateCounter *counter = new osgParticle::RandomRateCounter;
|
||
counter->setRateRange(60, 60);
|
||
emitter->setCounter(counter);
|
||
|
||
// setup the placer; it will be a circle of radius 5 (the particles will
|
||
// be placed inside this circle).
|
||
osgParticle::SectorPlacer *placer = new osgParticle::SectorPlacer;
|
||
placer->setCenter(8, 0, 10);
|
||
placer->setRadiusRange(2.5, 5);
|
||
placer->setPhiRange(0, 2 * osg::PI); // 360<36> angle to make a circle
|
||
emitter->setPlacer(placer);
|
||
|
||
// now let's setup the shooter; we use a RadialShooter but we set the
|
||
// initial speed to zero, because we want the particles to fall down
|
||
// only under the effect of the gravity force. Since we se the speed
|
||
// to zero, there is no need to setup the shooting angles.
|
||
osgParticle::RadialShooter *shooter = new osgParticle::RadialShooter;
|
||
shooter->setInitialSpeedRange(0, 0);
|
||
emitter->setShooter(shooter);
|
||
|
||
// add the emitter to the scene graph
|
||
root->addChild(emitter);
|
||
|
||
// WELL, we got our particle system and a nice emitter. Now we want to
|
||
// simulate the effect of the earth gravity, so first of all we have to
|
||
// create a Program. It is a particle processor just like the Emitter
|
||
// class, but it allows to modify particle properties *after* they have
|
||
// been created.
|
||
// The ModularProgram class can be thought as a sequence of operators,
|
||
// each one performing some actions on the particles. So, the trick is:
|
||
// create the ModularProgram object, create one or more Operator objects,
|
||
// add those operators to the ModularProgram, and finally add the
|
||
// ModularProgram object to the scene graph.
|
||
// NOTE: since the Program objects perform actions after the particles
|
||
// have been emitted by one or more Emitter objects, all instances of
|
||
// Program (and its descendants) should be placed *after* the instances
|
||
// of Emitter objects in the scene graph.
|
||
|
||
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);
|
||
|
||
// now create a custom operator, we have defined it before (see
|
||
// class VortexOperator).
|
||
VortexOperator *op2 = new VortexOperator;
|
||
op2->setCenter(osg::Vec3(8, 0, 0));
|
||
program->addOperator(op2);
|
||
|
||
// let's add a fluid operator to simulate air friction.
|
||
osgParticle::FluidFrictionOperator *op3 = new osgParticle::FluidFrictionOperator;
|
||
op3->setFluidToAir();
|
||
program->addOperator(op3);
|
||
|
||
// add the program to the scene graph
|
||
root->addChild(program);
|
||
|
||
// create a Geode to contain our particle system.
|
||
osg::Geode *geode = new osg::Geode;
|
||
geode->addDrawable(ps);
|
||
|
||
// add the geode to the scene graph.
|
||
root->addChild(geode);
|
||
|
||
return ps;
|
||
}
|
||
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////////////
|
||
// ANIMATED PARTICLE SYSTEM CREATION
|
||
//////////////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
osgParticle::ParticleSystem *create_animated_particle_system(osg::Group *root)
|
||
{
|
||
|
||
// Now we will create a particle system that uses two emitters to
|
||
// display two animated particles, one showing an explosion, the other
|
||
// a smoke cloud. A particle system can only use one texture, so
|
||
// the animations for both particles are stored in a single bitmap.
|
||
// The frames of the animation are stored in tiles. For each particle
|
||
// template, the start and end tile of their animation have to be given.
|
||
// The example file used here has 64 tiles, stored in eight rows with
|
||
// eight images each.
|
||
|
||
// First create a prototype for the explosion particle.
|
||
osgParticle::Particle pexplosion;
|
||
|
||
// The frames of the explosion particle are played from birth to
|
||
// death of the particle. So if lifetime is one second, all 16 images
|
||
// of the particle are shown in this second.
|
||
pexplosion.setLifeTime(1);
|
||
|
||
// some other particle properties just as in the last example.
|
||
pexplosion.setSizeRange(osgParticle::rangef(0.75f, 3.0f));
|
||
pexplosion.setAlphaRange(osgParticle::rangef(0.5f, 1.0f));
|
||
pexplosion.setColorRange(osgParticle::rangev4(
|
||
osg::Vec4(1, 1, 1, 1),
|
||
osg::Vec4(1, 1, 1, 1)));
|
||
pexplosion.setRadius(0.05f);
|
||
pexplosion.setMass(0.05f);
|
||
|
||
// This command sets the animation tiles to be shown for the particle.
|
||
// The first two parameters define the tile layout of the texture image.
|
||
// 8, 8 means the texture has eight rows of tiles with eight columns each.
|
||
// 0, 15 defines the start and end tile
|
||
pexplosion.setTextureTileRange(8, 8, 0, 15);
|
||
|
||
// The smoke particle is just the same, only plays another tile range.
|
||
osgParticle::Particle psmoke = pexplosion;
|
||
psmoke.setTextureTileRange(8, 8, 32, 45);
|
||
|
||
// Create a single particle system for both particle types
|
||
osgParticle::ParticleSystem *ps = new osgParticle::ParticleSystem;
|
||
|
||
// Assign the tiled texture
|
||
ps->setDefaultAttributes("Images/fireparticle8x8.png", false, false);
|
||
|
||
// Create two emitters, one for the explosions, one for the smoke balls.
|
||
osgParticle::ModularEmitter *emitter1 = new osgParticle::ModularEmitter;
|
||
emitter1->setParticleSystem(ps);
|
||
emitter1->setParticleTemplate(pexplosion);
|
||
|
||
osgParticle::ModularEmitter *emitter2 = new osgParticle::ModularEmitter;
|
||
emitter2->setParticleSystem(ps);
|
||
emitter2->setParticleTemplate(psmoke);
|
||
|
||
// create a counter each. We could reuse the counter for both emitters, but
|
||
// then we could not control the ratio of smoke balls to explosions
|
||
osgParticle::RandomRateCounter *counter1 = new osgParticle::RandomRateCounter;
|
||
counter1->setRateRange(10, 10);
|
||
emitter1->setCounter(counter1);
|
||
|
||
osgParticle::RandomRateCounter *counter2 = new osgParticle::RandomRateCounter;
|
||
counter2->setRateRange(3, 4);
|
||
emitter2->setCounter(counter2);
|
||
|
||
// setup a single placer for both emitters.
|
||
osgParticle::SectorPlacer *placer = new osgParticle::SectorPlacer;
|
||
placer->setCenter(-8, 0, 0);
|
||
placer->setRadiusRange(2.5, 5);
|
||
placer->setPhiRange(0, 2 * osg::PI); // 360<36> angle to make a circle
|
||
emitter1->setPlacer(placer);
|
||
emitter2->setPlacer(placer);
|
||
|
||
// the shooter is reused for both emitters
|
||
osgParticle::RadialShooter *shooter = new osgParticle::RadialShooter;
|
||
shooter->setInitialSpeedRange(0, 0);
|
||
|
||
// give particles a little spin
|
||
shooter->setInitialRotationalSpeedRange(osgParticle::rangev3(
|
||
osg::Vec3(0, 0, -1),
|
||
osg::Vec3(0, 0, 1)));
|
||
emitter1->setShooter(shooter);
|
||
emitter2->setShooter(shooter);
|
||
|
||
// add both emitters to the scene graph
|
||
root->addChild(emitter1);
|
||
root->addChild(emitter2);
|
||
|
||
// create a program, just as before
|
||
osgParticle::ModularProgram *program = new osgParticle::ModularProgram;
|
||
program->setParticleSystem(ps);
|
||
|
||
// create an operator that moves the particles upwards
|
||
osgParticle::AccelOperator *op1 = new osgParticle::AccelOperator;
|
||
op1->setAcceleration(osg::Vec3(0, 0, 2.0f));
|
||
program->addOperator(op1);
|
||
|
||
// add the program to the scene graph
|
||
root->addChild(program);
|
||
|
||
// create a Geode to contain our particle system.
|
||
osg::Geode *geode = new osg::Geode;
|
||
geode->addDrawable(ps);
|
||
|
||
// add the geode to the scene graph.
|
||
root->addChild(geode);
|
||
|
||
return ps;
|
||
}
|
||
|
||
//////////////////////////////////////////////////////////////////////////////
|
||
// MAIN SCENE GRAPH BUILDING FUNCTION
|
||
//////////////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
void build_world(osg::Group *root)
|
||
{
|
||
|
||
// In this function we are going to create two particle systems;
|
||
// the first one will be very simple, based mostly on default properties;
|
||
// the second one will be a little bit more complex, showing how to
|
||
// create custom operators.
|
||
// To avoid inserting too much code in a single function, we have
|
||
// splitted the work into two functions which accept a Group node as
|
||
// parameter, and return a pointer to the particle system they created.
|
||
|
||
osgParticle::ParticleSystem *ps1 = create_simple_particle_system(root);
|
||
osgParticle::ParticleSystem *ps2 = create_complex_particle_system(root);
|
||
osgParticle::ParticleSystem *ps3 = create_animated_particle_system(root);
|
||
|
||
// Now that the particle systems and all other related objects have been
|
||
// created, we have to add an "updater" node to the scene graph. This node
|
||
// will react to cull traversal by updating the specified particles system.
|
||
|
||
osgParticle::ParticleSystemUpdater *psu = new osgParticle::ParticleSystemUpdater;
|
||
psu->addParticleSystem(ps1);
|
||
psu->addParticleSystem(ps2);
|
||
psu->addParticleSystem(ps3);
|
||
|
||
// add the updater node to the scene graph
|
||
root->addChild(psu);
|
||
|
||
}
|
||
|
||
|
||
//////////////////////////////////////////////////////////////////////////////
|
||
// main()
|
||
//////////////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
int main(int, char **)
|
||
{
|
||
// construct the viewer.
|
||
osgViewer::Viewer viewer;
|
||
|
||
osg::Group *root = new osg::Group;
|
||
build_world(root);
|
||
|
||
// add the stats handler
|
||
viewer.addEventHandler(new osgViewer::StatsHandler);
|
||
|
||
// add a viewport to the viewer and attach the scene graph.
|
||
viewer.setSceneData(root);
|
||
|
||
return viewer.run();
|
||
}
|