Reputation: 26971
I would like to use AndEngine's particle system to create a splash(as in splashing water).
I have checked out the particle system example, but not really sure on what needs to be done to create a splash affect of water using the particle system.
Any idea's?
Upvotes: 2
Views: 5069
Reputation: 9115
I don't know of any water splash simulation algorithms, so I'll do what I think, but you will have to modify to make it look real.
Water splash animation in 2D will create many small water drops from a single location, then send each one in a different direction with an initial velocity, then each water drop slows down and fades out.
Try this out:
public ParticleSystem createParticleSystem(final TextureRegion waterDropTextureRegion) {
//X & Y for the particles to spawn at.
final float particlesXSpawn = 400;
final float particlesYSpawn = 300;
//Max & min rate are the maximum particles per second and the minimum particles per second.
final float maxRate = 10;
final float minRate = 5;
//This variable determines the maximum particles in the particle system.
final int maxParticles = 100;
//Particle emitter which will set all of the particles at a ertain point when they are initialized.
final PointParticleEmitter pointParticleEmtitter = new PointParticleEmitter(particlesXSpawn, particlesYSpawn);
//Creating the particle system.
final ParticleSystem particleSystem = new ParticleSystem(pointParticleEmtitter, maxRate, minRate, maxParticles, waterDropTextureRegion);
//And now, lets create the initiallizers and modifiers.
//Velocity initiallizer - will pick a random velocity from -20 to 20 on the x & y axes. Play around with this value.
particleSystem.addParticleInitializer(new VelocityInitializer(-20, 20, -20, 20));
//Acceleration initializer - gives all the particles the earth gravity (so they accelerate down).
particleSystem.addParticleInitializer(new GravityInitializer());
//And now, adding an alpha modifier, so particles slowly fade out. This makes a particle go from alpha = 1 to alpha = 0 in 3 seconds, starting exactly when the particle is spawned.
particleSystem.addParticleModifier(new AlphaModifier(1, 0, 0, 3));
//Lastly, expire modifier. Make particles die after 3 seconds - their alpha reached 0.
particleSystem.addParticleModifier(new ExpireModifier(3));
return particleSystem;
}
I haven't tested it, but I think it'd work. Try playing with the values to find an animation which looks reallistic.
The method receives an argument which is a ready texture region for each particle, in your case I guess that'd be a water drop.
After you call this method and get a ParticleSystem
, just attach it to your scene:
final ParticleSystem particleSystem = createParticleSystem(...);
scene.attachChild(particleSystem);
Upvotes: 3