import random


class SimulatedDiode(ReadonlyRegisterBase):

    def __init__(self, name):
        ReadonlyRegisterBase.__init__(self, name)
        self.x=0.0
        self.y=0.0
        self.radius=0.125
        self.amplitude = 600.0
        self.offset=200.0
        self.border = 0.025
        
    def doRead(self):     
        x,y = scx.position, scy.position       
        noise =  random.random() * self.amplitude/100.0
        d = math.hypot(x-self.x, y-self.y)
        #print d
        if d>self.radius:
            return self.offset + noise
        elif d< (self.radius - self.border ):
            return self.offset + noise + self.amplitude
        else :
            return self.offset + noise + self.amplitude *(self.radius - d)/self.border 
      
    def set_center(self, x, y):
        self.x, self.y = x, y