# Name : Liquid surface foam
# Description: Water -> Foam -> Water based on pressure
#
# Author 	:Richard Sutherland


# Directions:
# Create three emitters, name your main emitter water, and your secondary emitter foam, and your third emitter water2.
# 
# 

def onSimulationStep():
	pass
		
		
def onSimulationFrame():
	
	#Variable
	water = scene.getEmitter("water") #Name of the main fluid emitter.
	foam = scene.getEmitter("foam") #name of the spray emitter
	water2 = scene.getEmitter("water2") #name of the spray emitter

	
	press_to_foam=-1000 #must be below this to become foam, yes it CAN BE negative.  
	press_to_water=5000 #foam pressuer must be above this to become water again
	particle_skip=1#Setting this higher reduces foam
	
	part_count=0

	#loop through water Particles find collision's and emit foam.
	particles = water.getParticles()
	for particle in particles:
		part_count=part_count+1
		if(part_count % particle_skip ==0):
			press=particle.getPressure()
			if(press < press_to_foam):
				pos = particle.getPosition()
				vel = particle.getVelocity()
				foam.addParticle(pos, vel)
				water.removeParticle(particle.getId())
	
	#loop through foam particles and go back to water
	particles = foam.getParticles()
	for particle in particles:
		fpress=particle.getPressure()
		if(fpress > press_to_water):
			pos = particle.getPosition()
			vel = particle.getVelocity()
			water2.addParticle(pos, vel)
			foam.removeParticle(particle.getId())
				
					
	
def onSimulationBegin():
	pass
	
def onSimulationEnd():
	pass
	
	
def onChangeToFrame():
	pass