Source Code for Script script-demo_stickFilter_py

 1  from joy.decl import * 
 2  from joy import JoyApp, StickFilter 
 3  from pygame.event import Event as pygame_Event 
 4   
 5 -class StickFilterApp( JoyApp ): 
 6 -  def __init__(self,*arg,**kw): 
 7      JoyApp.__init__(self,*arg,**kw) 
 8     
 9 -  def onStart( self ): 
10      # Set up a StickFilter Plan 
11      sf = StickFilter(self) 
12      # Event channels can be names using a pygame event object, or using string 
13      #   names that follow a very strict structure. For tutorial puposes we 
14      #   show both options here. 
15      evt = pygame_Event(JOYAXISMOTION,joy=0,axis=0,value=None) 
16      # This channel is lowpass filtered -- useful for direct position control     
17      sf.setLowpass( evt, 5 ) 
18      # This channel is integrated, saturating at +/- 9. 
19      sf.setIntegrator( "joy0axis1", lower=-9, upper=9) 
20      # This channel is integrated, saturating at +/- 9. 
21      sf.setIntegrator( "midi3sc1slider2", lower=-9, upper=9, func = lambda x : (x-63.5)/64 ) 
22      # Start it up, otherwise nothing will happen... 
23      sf.start() 
24      self.sf = sf 
25      # Set up a temporal filter for controlling the rate of our messages to the 
26      #  operator. In this case, we want 4 messages a second 
27      self.timeToShow = self.onceEvery(0.25) 
28           
29 -  def onEvent( self, evt ): 
30      # If its time to show the operator a status message --> do so 
31      if self.timeToShow(): 
32        progress("State x %.3f y %.3f sc1slider2 %.3f" % ( 
33          self.sf.getValue("joy0axis0"), self.sf.getValue("joy0axis1"), self.sf.getValue("midi3sc1slider2")  
34        )) 
35      # Send all joystick motion events to our StickFilter 
36      if evt.type in [JOYAXISMOTION,MIDIEVENT]: 
37        self.sf.push(evt) 
38        return 
39      # If we got this far, let our superclass handle the event  
40      #  This provides a debug printout and the option to quit via [escape] or [q] 
41      JoyApp.onEvent(self,evt) 
42   
43  if __name__=="__main__": 
44    print """ 
45      Demonstration of the StickFilter plan 
46      ------------------------------------- 
47       
48      Shows the use of the StickFilter plan, which allows arbitrary 
49      linear filters to be applied to input channels. This includes 
50      integrating joystick inputs, smoothing encoder measurements,  
51      etc. 
52       
53      The example shows how axis 0 can be set to low-pass filtering, 
54      and axis 1 to integration. 
55    """ 
56    app = StickFilterApp() 
57    app.run() 
58