I find really easy to use ParticleEmitter for 2D sprite animation. The only thing missing is the ability to control the Particle.imageIndex for supporting sprite sheets containing more than one animation in the same image.
Currently the behaviour is that Particle.imageIndex is running from 0 to X*Y assuming the sprite sheet contains one animation.
So I thought of extending ParticleEmitter and overriding:
protected void updateParticle(Particle p, float tpf, Vector3f min, Vector3f max)
to control the Particle.imageIndex strategy.
What do you think - is that a good path to go?