Lost pipette zorder with animation
I am trying to animate different objects in the same graph using corn flexization.
It works almost as I expect, except for the order in which the different items are displayed. In this way, the graphic curve, text and legend are displayed behind the image, where they are barely visible.
Here's my (not so) minimal working example:
#! /usr/bin/python
import numpy as np
from matplotlib import pyplot as plt
from matplotlib import animation
import random
def init():
line_simu.set_data([], [])
time_text.set_text('')
imobj.set_data(np.zeros((100, 100)))
imobj.set_zorder(0)
time_text.set_zorder(10)
return line_simu, time_text, imobj
def animate(i):
imobj.set_zorder(0)
time_text.set_zorder(10)
y_simu = np.linspace(0,100, 100)
x_simu = np.linspace(-10, 10, 100)
line_simu.set_data(x_simu, y_simu)
time_text.set_text('time = %.1f' % i )
global data
imobj.set_data( data + np.random.random((100,1)) * 0.5 )
return line_simu, time_text, imobj
def forceAspect(ax,aspect=1):
im = ax.get_images()
extent = im[0].get_extent()
ax.set_aspect(abs((extent[1]-extent[0])/(extent[3]-extent[2]))/aspect)
fig = plt.figure()
ax = plt.axes(xlim=(-15,15), ylim=(-110, 0) , aspect=1)
data = np.random.random((100,100)) - .5
imobj = ax.imshow( data , extent=[-15,15, -110, 0.0], origin='lower', cmap=plt.cm.gray, vmin=-2, vmax=2, alpha=.7, zorder=0, aspect=1)
line_simu, = ax.plot([], [],"r--", lw=2, markersize=4 , label = "Some curve" , zorder= 2 )
time_text = ax.text(-14.9, -108, '', zorder=10)
l = plt.legend(loc='lower right', prop={'size':8} )
l.set_zorder(200)
forceAspect(ax,aspect=1)
anim = animation.FuncAnimation(fig, animate, init_func=init, frames=range( 50), interval=3000, blit=True)
plt.show()
Without animation, I can easily control the order of the various elements with set_zorder, but when the animation updates the image, that order is lost. I have tried setting zorder in init function and again in animation function with no success.
I am very grateful for any help on this issue.
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To answer my own question: The order seems to be that the return functions init () and animate () return objects controls the order in which they are displayed. In addition, these functions must return a legend object to be included in the animation.
Here is my corrected code:
#! /usr/bin/python
import numpy as np
from matplotlib import pyplot as plt
from matplotlib import animation
import random
def init():
imobj.set_data(np.zeros((100, 100)))
line_simu.set_data([], [])
time_text.set_text('time = 0.0')
return imobj , line_simu, time_text, l
def animate(i):
global data
imobj.set_data( data + np.random.random((100,1)) * 0.5 )
imobj.set_zorder(0)
y_simu = np.linspace(-100,-10, 100)
x_simu = np.linspace(-10, 10, 100)
line_simu.set_data(x_simu, y_simu)
time_text.set_text('time = %.1f' % i )
return imobj , line_simu, time_text, l
def forceAspect(ax,aspect=1):
im = ax.get_images()
extent = im[0].get_extent()
ax.set_aspect(abs((extent[1]-extent[0])/(extent[3]-extent[2]))/aspect)
fig = plt.figure()
ax = plt.axes(xlim=(-15,15), ylim=(-110, 0) , aspect=1)
data = np.random.random((100,100)) - .5
imobj = ax.imshow( data , extent=[-15,15, -110, 0.0], origin='lower', cmap=plt.cm.gray, vmin=-2, vmax=2, alpha=1.0, zorder=1, aspect=1)
line_simu, = ax.plot([], [],"r--", lw=2, markersize=4 , label = "Some curve" , zorder= 1 )
time_text = ax.text(-14.0, -108, '', zorder=10)
forceAspect(ax,aspect=1)
l = plt.legend(loc='lower right', prop={'size':8} )
anim = animation.FuncAnimation(fig, animate, init_func=init, frames=range( 50), interval=500, blit=True)
plt.show()
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