Controlling the MeArm Pi from Minecraft

mearm.py

import os
import math
import pigpio
#import RPi.GPIO as GPIO

pi = pigpio.pi()

class Servo:
  def __init__(self, config):
    self.pin = config['pin']
    self.min = config['min']
    self.max = config['max']
    self.minAngle = config['minAngle']
    self.maxAngle = config['maxAngle']

  def moveTo(self, angle):
    self.moveToAngle(angle)

  def moveBy(self, angle):
    newAngle = self.currentAngle + angle
    self.moveToAngle(newAngle)

  def moveToCentre(self):
    centre = self.minAngle + (self.maxAngle - self.minAngle)/2
    self.moveToAngle(centre)

  def moveToAngle(self, angle):
    if angle > self.maxAngle:
      angle = self.maxAngle
    if angle < self.minAngle:
      angle = self.minAngle
    self.currentAngle = angle
    self.updateServo()

  def updateServo(self):
    pulseWidth = math.floor(self.min + ((float(self.currentAngle - self.minAngle) / float(self.maxAngle - self.minAngle)) * (self.max - self.min)));
    pi.set_servo_pulsewidth(self.pin, pulseWidth)

class MeArm:
  def __init__(self):
    self.base =  Servo({'pin': 4, 'min': 530, 'max': 2400, 'minAngle': -90, 'maxAngle': 90});
    self.lower = Servo({'pin': 17, 'min': 530, 'max': 1450, 'minAngle': 0, 'maxAngle': 90});
    self.upper = Servo({'pin': 22, 'min': 530, 'max': 2000, 'minAngle': 0, 'maxAngle': 135});
    self.grip =  Servo({'pin': 10, 'min': 1400, 'max': 2400, 'minAngle': 0, 'maxAngle': 90});

  def moveToCentres(self):
    self.base.moveToCentre()
    self.lower.moveToCentre()
    self.upper.moveToCentre()
    self.grip.moveToCentre()

mearmcraft.py

import RPi.GPIO as GPIO
import mcpi.minecraft as minecraft
import mcpi.block as block
import mcpi.vec3 as vec3
from mearm import MeArm
mc = minecraft.Minecraft.create()

active = False

arm = MeArm()
arm.moveToCentres()

GPIO.setmode(GPIO.BCM)
GPIO.setup(5, GPIO.IN, pull_up_down=GPIO.PUD_UP)
GPIO.setup(6, GPIO.IN, pull_up_down=GPIO.PUD_UP)

controls = []
oldBlocks = []

class ControlBlock:
  def __init__(self, servo, amount, x, y, z, colour):
    mc.setBlocks(x, y, z, x, y+3, z, block.WOOL.id, colour)
    self.servo = servo
    self.amount = amount
    self.x = x
    self.z = z

  def trigger(self):
    servo = getattr(arm, self.servo)
    servo.moveBy(self.amount*6)

def buildBase(width=10):
  print "Build Base"
  w = width/2
  pos = mc.player.getPos()
  mc.setBlocks(pos.x-w, pos.y-1, pos.z-w, pos.x+w, pos.y-2, pos.z+w, block.IRON_BLOCK.id)
  mc.setBlocks(pos.x-w, pos.y, pos.z-w, pos.x+w, pos.y+20, pos.z+w, block.AIR.id)

def buildControls():
  print "Build Controls"
  currentPos = mc.player.getPos()
  x, y, z = currentPos
  x = int(x)
  y = int(y)
  z = int(z)
  controls.append(ControlBlock('base', -1,  x+2, y, z+1, 1))
  controls.append(ControlBlock('base', 1, x+2, y, z-1, 1))
  mc.setBlock(x+2, y, z, block.TORCH.id)
  controls.append(ControlBlock('lower', -1, x+1, y, z+2, 5))
  controls.append(ControlBlock('lower', 1, x-1, y, z+2, 5))
  mc.setBlock(x, y+1, z+2, block.TORCH.id)
  controls.append(ControlBlock('upper', 1, x-2, y, z+1, 3))
  controls.append(ControlBlock('upper', -1, x-2, y, z-1, 3))
  mc.setBlock(x-2, y+2, z, block.TORCH.id)
  controls.append(ControlBlock('grip', 1, x+1, y, z-2, 10))
  controls.append(ControlBlock('grip', -1, x-1, y, z-2, 10))
  mc.setBlock(x, y+3, z-2, block.TORCH.id)

def identifyBlock(pos):
  x,y,z = pos
  for control in controls:
    if x == control.x and z == control.z:
      return control
  return None

def start():
  print "Start controls"
  buildBase()
  buildControls()

def end():
  print "End controls"
  buildBase()

while True:
  if not GPIO.input(5) and not active:
    active = True
    start()
  if not GPIO.input(6) and active:
    active = False
    end()
  #Get the block hit events
  blockHits = mc.events.pollBlockHits()
  # if a block has been hit
  if blockHits and len(controls) > 0:
    # for each block that has been hit
    for blockHit in blockHits:
      myblock = identifyBlock(blockHit.pos)
      if myblock:
        myblock.trigger()