camera_shake.script

function update(self, dt)
  local camera_pos=self.original_position or go.get_position()

	self.shake=vmath.vector3()
	if self.shakes and next(self.shakes) then
		for i,shake in pairs(self.shakes) do
			shake.time=shake.time-dt
			shake.to_target=shake.to_target-dt
			if shake.to_target<=0 then
				shake.a=vmath.vector3(shake.b)
				shake.b=vmath.vector3((math.random()-0.5)*shake.x,(math.random()-0.5)*shake.y, 0)
				shake.to_target=math.min(shake.time, shake.speed)
				shake.to_target_max=shake.to_target
			end
			self.shake=self.shake+vmath.lerp(shake.to_target/shake.to_target_max, shake.b, shake.a)
			if shake.time<=0 then
				table.remove(self.shakes, i)
			end
		end
	elseif self.original_position then
		camera_pos=self.original_position
		self.original_position=nil
	end

    go.set_position(camera_pos+self.shake)
end

function on_message(self, message_id, message, sender)
	if message_id==hash("shake") then
		self.original_position=go.get_position()
		if not self.shakes then
			self.shakes={}
		end
		message.to_target=0
		message.a=vmath.vector3()
		message.b=vmath.vector3()
		table.insert(self.shakes, message)
	end
end

function on_reload(self)
	msg.post("#", "shake", {time=2.75, x=35, y=35, speed=0.033})
end