.. _old_animation-animation_blit_fltk:

old_animation example code: animation_blit_fltk.py
==================================================

[`source code <animation_blit_fltk.py>`_]

::

    from __future__ import print_function
    import sys
    import fltk
    import matplotlib
    matplotlib.use('FltkAgg')
    import pylab as p
    import numpy as npy
    import time
    
    
    # save the clean slate background -- everything but the animated line
    # is drawn and saved in the pixel buffer background
    class animator:
        def __init__(self,ax):
            self.ax=ax
            self.canvas=ax.figure.canvas
            self.canvas.mpl_connect('draw_event',self.clear)
            self.cnt=0
            self.background=None
    
            # for profiling
            self.tstart = time.time()
    
        def clear(self,event):
            self.background = self.canvas.copy_from_bbox(self.ax.bbox)
    
        def update(self,ptr):
            # restore the clean slate background
            if self.background is None:
                self.background = self.canvas.copy_from_bbox(self.ax.bbox)
            self.canvas.restore_region(self.background)
            # update the data
            line.set_ydata(npy.sin(x+self.cnt/10.0))
            # just draw the animated artist
            self.ax.draw_artist(line)
            # just redraw the axes rectangle
            self.canvas.blit(ax.bbox)
            self.cnt+=1
            if self.cnt==1000:
                # print the timing info and quit
                print('FPS:' , 1000/(time.time()-self.tstart))
                sys.exit()
            return True
    
    ax = p.subplot(111)
    p.subplots_adjust(left=0.3, bottom=0.3) # check for flipy bugs
    p.grid() # to ensure proper background restore
    # create the initial line
    x = npy.arange(0,2*npy.pi,0.01)
    line, = p.plot(x, npy.sin(x), animated=True)
    p.draw()
    anim=animator(ax)
    
    fltk.Fl.add_idle(anim.update)
    fltk.Fl.run()
    

Keywords: python, matplotlib, pylab, example, codex (see :ref:`how-to-search-examples`)