title: Shading over plot with funcanimation
body: <p>I'm trying to shade over a map to show &quot;explored regions&quot; of the dot as it moves around using FuncAnimation. This is the code I have so far:</p>
  <pre><code>import matplotlib.pyplot as plt 
  import matplotlib.patches as patches
  import matplotlib.animation as animation
  import numpy as np
  import random
  import scipy.stats as stats
  
  map_x = 100
  map_y = 100
  fig = plt.figure(0)
  plt.figure(0)
  ax1 = plt.subplot2grid((2,3), (0,0), colspan=2, rowspan=2)
  ax2 = plt.subplot2grid((2,3), (0,2), colspan=1)
  ax1.set_xlim([0, map_x])
  ax1.set_ylim([0, map_y])
  ax2.set_xlim([0, map_x])
  ax2.set_ylim([0, map_y])
  agent = plt.Circle((50, 1), 2, fc='r')
  agent2 = plt.Circle((50, 1), 2, fc='r')
  agents = [agent, agent2]
  ax1.add_patch(agent)
  ax2.add_patch(agent2)
  
  def animate(i):
      x, y = agent.center
      x = x+.1
      y = y+.1
      agent.center = (x, y)
      agent2.center = (x, y)
      return agent,
  
  def fillMap(x, y):
      circle=plt.Circle((x,y), 4, fc='b')
      ax2.add_patch(circle)
  
  def animate2(i):
      x, y = agent2.center
      x = x+.1
      y = y+.1
      agent2.center = (x, y)
      fillMap(x, y)
      return agent2,
  
  anim = animation.FuncAnimation(fig, animate, frames=200, interval=20, blit=True)
  anim2 = animation.FuncAnimation(fig, animate2, frames=200, interval=20, blit=True)
  
  plt.show()
  </code></pre>
  <p>However, it only goes into fillMap once, and only draws the blue filled in circle once, instead of everywhere where the red dot goes in the smaller subplot.</p>