.. _event_handling-pipong: event_handling example code: pipong.py ====================================== [`source code `_] :: #!/usr/bin/env python # A matplotlib based game of Pong illustrating one way to write interactive # animation which are easily ported to multiple backends # pipong.py was written by Paul Ivanov from __future__ import print_function import numpy as np import matplotlib.pyplot as plt from numpy.random import randn, randint instructions = """ Player A: Player B: 'e' up 'i' 'd' down 'k' press 't' -- close these instructions (animation will be much faster) press 'a' -- add a puck press 'A' -- remove a puck press '1' -- slow down all pucks press '2' -- speed up all pucks press '3' -- slow down distractors press '4' -- speed up distractors press ' ' -- reset the first puck press 'n' -- toggle distractors on/off press 'g' -- toggle the game on/off """ class Pad(object): def __init__(self, disp,x,y,type='l'): self.disp = disp self.x = x self.y = y self.w = .3 self.score = 0 self.xoffset = 0.3 self.yoffset = 0.1 if type=='r': self.xoffset *= -1.0 if type=='l' or type=='r': self.signx = -1.0 self.signy = 1.0 else: self.signx = 1.0 self.signy = -1.0 def contains(self, loc): return self.disp.get_bbox().contains(loc.x,loc.y) class Puck(object): def __init__(self, disp, pad, field): self.vmax= .2 self.disp = disp self.field = field self._reset(pad) def _reset(self,pad): self.x = pad.x + pad.xoffset if pad.y < 0: self.y = pad.y + pad.yoffset else: self.y = pad.y - pad.yoffset self.vx = pad.x - self.x self.vy = pad.y + pad.w/2 - self.y self._speedlimit() self._slower() self._slower() def update(self,pads): self.x += self.vx self.y += self.vy for pad in pads: if pad.contains(self): self.vx *= 1.2 *pad.signx self.vy *= 1.2 *pad.signy fudge = .001 #probably cleaner with something like...if not self.field.contains(self.x, self.y): if self.x < 0+fudge: #print "player A loses" pads[1].score += 1; self._reset(pads[0]) return True if self.x > 7-fudge: #print "player B loses" pads[0].score += 1; self._reset(pads[1]) return True if self.y < -1+fudge or self.y > 1-fudge: self.vy *= -1.0 # add some randomness, just to make it interesting self.vy -= (randn()/300.0 + 1/300.0) * np.sign(self.vy) self._speedlimit() return False def _slower(self): self.vx /= 5.0 self.vy /= 5.0 def _faster(self): self.vx *= 5.0 self.vy *= 5.0 def _speedlimit(self): if self.vx > self.vmax: self.vx = self.vmax if self.vx < -self.vmax: self.vx = -self.vmax if self.vy > self.vmax: self.vy = self.vmax if self.vy < -self.vmax: self.vy = -self.vmax class Game(object): def __init__(self, ax): # create the initial line self.ax = ax padAx = padBx= .50 padAy = padBy= .30 padBx+=6.3 pA, = self.ax.barh(padAy,.2, height=.3,color='k', alpha=.5, edgecolor='b',lw=2,label="Player B", animated=True) pB, = self.ax.barh(padBy,.2, height=.3, left=padBx, color='k',alpha=.5, edgecolor='r',lw=2,label="Player A",animated=True) # distractors self.x = np.arange(0,2.22*np.pi,0.01) self.line, = self.ax.plot(self.x, np.sin(self.x),"r", animated=True, lw=4) self.line2, = self.ax.plot(self.x, np.cos(self.x),"g", animated=True, lw=4) self.line3, = self.ax.plot(self.x, np.cos(self.x),"g", animated=True, lw=4) self.line4, = self.ax.plot(self.x, np.cos(self.x),"r", animated=True, lw=4) self.centerline,= self.ax.plot([3.5,3.5], [1,-1],'k',alpha=.5, animated=True, lw=8) self.puckdisp = self.ax.scatter([1],[1],label='_nolegend_', s=200,c='g',alpha=.9,animated=True) self.canvas = self.ax.figure.canvas self.background = None self.cnt = 0 self.distract = True self.res = 100.0 self.on = False self.inst = True # show instructions from the beginning self.background = None self.pads = [] self.pads.append( Pad(pA,0,padAy)) self.pads.append( Pad(pB,padBx,padBy,'r')) self.pucks =[] self.i = self.ax.annotate(instructions,(.5,0.5), name='monospace', verticalalignment='center', horizontalalignment='center', multialignment='left', textcoords='axes fraction',animated=True ) self.canvas.mpl_connect('key_press_event', self.key_press) def draw(self, evt): draw_artist = self.ax.draw_artist if self.background is None: self.background = self.canvas.copy_from_bbox(self.ax.bbox) # restore the clean slate background self.canvas.restore_region(self.background) # show the distractors if self.distract: self.line.set_ydata(np.sin(self.x+self.cnt/self.res)) self.line2.set_ydata(np.cos(self.x-self.cnt/self.res)) self.line3.set_ydata(np.tan(self.x+self.cnt/self.res)) self.line4.set_ydata(np.tan(self.x-self.cnt/self.res)) draw_artist(self.line) draw_artist(self.line2) draw_artist(self.line3) draw_artist(self.line4) # show the instructions - this is very slow if self.inst: self.ax.draw_artist(self.i) # pucks and pads if self.on: self.ax.draw_artist(self.centerline) for pad in self.pads: pad.disp.set_y(pad.y) pad.disp.set_x(pad.x) self.ax.draw_artist(pad.disp) for puck in self.pucks: if puck.update(self.pads): # we only get here if someone scored self.pads[0].disp.set_label(" "+ str(self.pads[0].score)) self.pads[1].disp.set_label(" "+ str(self.pads[1].score)) self.ax.legend(loc='center') self.leg = self.ax.get_legend() #self.leg.draw_frame(False) #don't draw the legend border self.leg.get_frame().set_alpha(.2) plt.setp(self.leg.get_texts(),fontweight='bold',fontsize='xx-large') self.leg.get_frame().set_facecolor('0.2') self.background = None self.ax.figure.canvas.draw() return True puck.disp.set_offsets([puck.x,puck.y]) self.ax.draw_artist(puck.disp) # just redraw the axes rectangle self.canvas.blit(self.ax.bbox) if self.cnt==50000: # just so we don't get carried away print("...and you've been playing for too long!!!") plt.close() self.cnt += 1 return True def key_press(self,event): if event.key == '3': self.res *= 5.0 if event.key == '4': self.res /= 5.0 if event.key == 'e': self.pads[0].y += .1 if self.pads[0].y > 1 - .3: self.pads[0].y = 1-.3 if event.key == 'd': self.pads[0].y -= .1 if self.pads[0].y < -1: self.pads[0].y = -1 if event.key == 'i': self.pads[1].y += .1 if self.pads[1].y > 1 - .3: self.pads[1].y = 1-.3 if event.key == 'k': self.pads[1].y -= .1 if self.pads[1].y < -1: self.pads[1].y = -1 if event.key == 'a': self.pucks.append(Puck(self.puckdisp,self.pads[randint(2)],self.ax.bbox)) if event.key == 'A' and len(self.pucks): self.pucks.pop() if event.key == ' ' and len(self.pucks): self.pucks[0]._reset(self.pads[randint(2)]) if event.key == '1': for p in self.pucks: p._slower() if event.key == '2': for p in self.pucks: p._faster() if event.key == 'n': self.distract = not self.distract if event.key == 'g': #self.ax.clear() self.on = not self.on if event.key == 't': self.inst = not self.inst self.i.set_visible(self.i.get_visible()) if event.key == 'q': plt.close() Keywords: python, matplotlib, pylab, example, codex (see :ref:`how-to-search-examples`)