protected void updateParticle(Particle p, float tpf, Vector3f min, Vector3f max) {
        // applying gravity
        p.velocity.x -= gravity.x * tpf;
        p.velocity.y -= gravity.y * tpf;
        p.velocity.z -= gravity.z * tpf;
        temp.set(p.velocity).multLocal(tpf);
        p.position.addLocal(temp);

        // affecting color, size and angle
        float b = (p.startlife - p.life) / p.startlife;
        p.color.interpolateLocal(startColor, endColor, b);
        p.size = FastMath.interpolateLinear(b, startSize, endSize);
        p.angle += p.rotateSpeed * tpf;

        // Computing bounding volume
        computeBoundingVolume(p, min, max);

        if (!selectRandomImage) {
            p.imageIndex = (int) (b * imagesX * imagesY);
        }
    }
Kills the particle at the given index.

@param index The index of the particle to kill
@see #getParticles()
jme3-core/src/main/java/com/jme3/effect/ParticleEmitter.java