Particle = Entity:New(x,y)

function Particle:New(x,y,particle_data)
	local o = Entity:New(x,y)

	o.pos = {x = x, y = y}


	o.speed = particle_data.speed or 0
	o.direction = particle_data.direction or o.direction
	o.sprite_rotation = particle_data.sprite_rotation or o.sprite_rotation
	o.sprite_offset = particle_data.sprite_offset or o.sprite_offset
	o.sprite_scale = particle_data.sprite_scale or o.sprite_scale
	o.sprite_tint = particle_data.sprite_tint or o.sprite_tint
	o.sprite_alpha = particle_data.sprite_alpha or o.sprite_alpha
	o.sprite_alpha_base = o.sprite_alpha

	o.sprite_flip = particle_data.sprite_flip or o.sprite_flip
	o.animation_active = particle_data.animation_active or false

	o.time = 0.5
	o.timer = 0

	o.vel = {
		x = o.speed * math.cos(o.direction),
		y = o.speed * math.sin(o.direction)
	}

	if particle_data.light ~= nil then
		o.lightRange = particle_data.light
		o.light = CreateLight(o.pos.x,o.pos.y,o.lightRange)
	end

	-- animations
	o.body = Animation:New(particle_data.animation)
	o:centerOffset(o.body)
	if not o.animation_active then
		o.body.speed = 0
	end

	table.insert(LoadedParticles,o)
	o.id = #LoadedParticles

	setmetatable(o, self)
	self.__index = self
	return o
end

function Particle:Kill()
	if self.light ~= nil then
		KillLight(self.light)
	end
	if self.id ~= nil then
		for _, e in pairs(LoadedParticles) do
			if e.id > self.id then
				e.id = e.id - 1
			end
		end
		table.remove(LoadedParticles,self.id)
	end
	self = nil
end

function Particle:HandleAnimation()
	self.body:Animate()
	self.timer = self.timer + current_dt
	self.sprite_alpha = self.sprite_alpha_base*(self.time-self.timer)/self.time
	if self.light ~= nil then
		self.light.range = self.lightRange * self.sprite_alpha/2
	end
	if self.sprite_alpha < 0 then self:Kill() end
	self:Draw(self.body)
end

function Particle:DoPhysics()
	if not self:isCollidingAt(self.pos.x + self.vel.x, self.pos.y, objects.collisions) then
		self.pos.x = self.pos.x + self.vel.x
	end
	if not self:isCollidingAt(self.pos.x, self.pos.y + self.vel.y, objects.collisions) then
		self.pos.y = self.pos.y + self.vel.y
	end
end