Factor out a pippy library, which programs can use with 'import pippy'.

The pygame portion of the library uses 'best practices' to avoid eating
up CPU, and pauses & suspends after 20 seconds of inactivity.

18 files changed, 117 insertions, 58 deletions

diff --git a/activity.py b/activity.py
index 868cc03..ec15a16 100644
--- a/activity.py
+++ b/activity.py
@@ -216,7 +216,13 @@ class PippyActivity(Activity):
             file.write(line)
         file.close()
 
-        self._pid = self._vte.fork_command("/bin/sh", ["/bin/sh", "-c", "python /tmp/pippy.py; sleep 1"])
+        self._pid = self._vte.fork_command \
+                    (command="/bin/sh",
+                     argv=["/bin/sh", "-c",
+                           "python /tmp/pippy.py; sleep 1"],
+                     envv=["PYTHONPATH=%s/library" % get_bundle_path()],
+                     directory=get_bundle_path(),
+                     lastlog=False, utmp=False, wtmp=False)
 
     def stopbutton_cb(self, button):
         os.kill(self._pid, SIGTERM)	
diff --git a/data/graphics/bounce b/data/graphics/bounce
index 02bc34f..d0bcd3c 100644
--- a/data/graphics/bounce
+++ b/data/graphics/bounce
@@ -1,6 +1,6 @@
 # bounce: move some text around the screen
 
-import sys,pygame
+import pippy, pygame, sys
 from pygame.locals import *
 from random import *
 
@@ -44,7 +44,7 @@ textRect = text.get_rect()
 textRect.left = 0;
 textRect.top = 0;
 
-while 1:
+while pippy.pygame.next_frame():
 
   for event in pygame.event.get():
     if event.type == QUIT:
diff --git a/data/graphics/camera b/data/graphics/camera
index 8a1bbb8..6eea88f 100644
--- a/data/graphics/camera
+++ b/data/graphics/camera
@@ -1,6 +1,6 @@
 # image: take a picture
 
-import sys, pygame, gst, time
+import gst, pippy, pygame, sys, time
 from random import *
 
 # XO screen is 1200 by 900
@@ -32,7 +32,7 @@ image = pygame.image.load("/tmp/pippypic.jpg")
 angle = 0.0
 scale = 2.0
 
-while 1:
+while pippy.pygame.next_frame():
   for event in pygame.event.get():
     if event.type == pygame.QUIT: sys.exit()
     elif event.type == pygame.KEYDOWN: sys.exit()
diff --git a/data/graphics/jump b/data/graphics/jump
index ed08950..be9b49e 100644
--- a/data/graphics/jump
+++ b/data/graphics/jump
@@ -1,31 +1,27 @@
-def clear_scr():
-    print '\x1B[H\x1B[J' # clear screen
-
-def wait():
-    import time
-    time.sleep(0.1)
+import pippy
 
 for i in xrange(0,50):
-    clear_scr()
+    pippy.console.clear()
+    # Note that we have to escape backslashes
     print "\\o/"
     print "_|_"
     print "   "
-    wait()
+    pippy.wait()
     
-    clear_scr()
+    pippy.console.clear()
     print "_o_"
     print " | "
     print "/ \\"
-    wait()
+    pippy.wait()
     
-    clear_scr()
+    pippy.console.clear()
     print " o "
     print "/|\\"
     print "| |"
-    wait()
+    pippy.wait()
     
-    clear_scr()
+    pippy.console.clear()
     print "_o_"
     print " | "
     print "/ \\"
-    wait()
+    pippy.wait()
diff --git a/data/graphics/lines b/data/graphics/lines
index 682ab37..c0faf93 100644
--- a/data/graphics/lines
+++ b/data/graphics/lines
@@ -1,6 +1,6 @@
 # lines: make lots of lines on the screen
 
-import sys,pygame
+import pippy, pygame, sys
 from pygame.locals import *
 from random import *
 
@@ -32,7 +32,7 @@ mvect_end   = [choice((-1,1)) * randint(1,3), choice((-1,1)) * randint(1,3)]
 color = [randint(0,255), randint(0,255), randint(0,255)]
 direction = [choice((-1,1)), choice((-1,1)), choice((-1,1))]
 
-while 1:
+while pippy.pygame.next_frame():
 
   for event in pygame.event.get():
     if event.type == QUIT:
diff --git a/data/graphics/pong b/data/graphics/pong
index 351f7ce..0ce3a9e 100644
--- a/data/graphics/pong
+++ b/data/graphics/pong
@@ -5,7 +5,7 @@
 # on the XO, the escape key is the top lefthand key,
 # circle with an x in it.
 
-import sys,pygame
+import pippy, pygame, sys
 from pygame.locals import *
 from random import *
 
@@ -50,7 +50,7 @@ textRect = text.get_rect()
 textRect.centerx = screen.get_rect().centerx
 textRect.centery = screen.get_rect().centery
 
-while 1:
+while pippy.pygame.next_frame():
 
   # display msg
   screen.fill(bgcolor)
diff --git a/data/math/guess b/data/math/guess
index 97ee098..d80514c 100644
--- a/data/math/guess
+++ b/data/math/guess
@@ -1,6 +1,5 @@
 import random
-from random import randrange
-R = randrange(1,100)
+R = random.randrange(1,100)
 
 print "Guess a number between 1 and 100!"
 N = input("Enter a number: ")
diff --git a/data/math/sierpinski b/data/math/sierpinski
index 133acc4..8b5f291 100644
--- a/data/math/sierpinski
+++ b/data/math/sierpinski
@@ -14,13 +14,13 @@ for i in range(0,lines):
   newvector = vector[:]
   for j in range(0,len(vector)-1):
     if (newvector[j] == 0):
-      sys.stdout.write(" ")
+      print " ",
     else:
       remainder = newvector[j] % modulus
       if (remainder == 0):
-        sys.stdout.write("O")
+        print "O",
       else:
-        sys.stdout.write(".")
+        print ".",
     newvector[j] = vector[j-1] + vector[j+1]
   print
   vector = newvector[:]
diff --git a/data/sound/getSoundList b/data/sound/getSoundList
index 215e97a..8d722bb 100644
--- a/data/sound/getSoundList
+++ b/data/sound/getSoundList
@@ -1,7 +1,4 @@
-import sys
-from sugar.activity.activity import get_bundle_path
-sys.path.append(get_bundle_path() + '/sound')
-from sound import *
+import pippy
 
-for sound in getSoundList():
+for sound in pippy.sound.getSoundList():
     print sound
diff --git a/data/sound/playSine b/data/sound/playSine
index cd97576..b68746c 100644
--- a/data/sound/playSine
+++ b/data/sound/playSine
@@ -1,8 +1,5 @@
-import sys
-from sugar.activity.activity import get_bundle_path
-sys.path.append(get_bundle_path() + '/sound')
-from sound import *
+import pippy
 
-playSine()
-audioOut()
+pippy.sound.playSine()
+pippy.sound.audioOut()
         
diff --git a/data/sound/playWave b/data/sound/playWave
index 27605bd..503b475 100644
--- a/data/sound/playWave
+++ b/data/sound/playWave
@@ -1,8 +1,5 @@
-import sys
-from sugar.activity.activity import get_bundle_path
-sys.path.append(get_bundle_path() + '/sound')
-from sound import *
+import pippy
 
-playWave(sound='didjeridu', loop=True, duration=5)
-audioOut()
+pippy.sound.playWave(sound='didjeridu', loop=True, duration=5)
+pippy.sound.audioOut()
         
diff --git a/data/sound/sequence b/data/sound/sequence
index 1577c9d..3922e7a 100644
--- a/data/sound/sequence
+++ b/data/sound/sequence
@@ -1,14 +1,10 @@
-import sys
-import random
-from sugar.activity.activity import get_bundle_path
-sys.path.append(get_bundle_path() + '/sound')
-from sound import *
+import pippy, random
 
 for i in range(25):
     pitch = random.randint(500,2000)
     amplitude = 5000
     duration = 0.1
     starttime = i * 0.1
-    playSine(pitch, amplitude, duration, starttime)
-audioOut()
+    pippy.sound.playSine(pitch, amplitude, duration, starttime)
+pippy.sound.audioOut()
 
diff --git a/data/sound/sndInfo b/data/sound/sndInfo
index 529995e..7767245 100644
--- a/data/sound/sndInfo
+++ b/data/sound/sndInfo
@@ -1,6 +1,2 @@
-import sys
-from sugar.activity.activity import get_bundle_path
-sys.path.append(get_bundle_path() + '/sound')
-from sound import *
-
-print playSine.__doc__
+import pippy
+help(pippy.sound.playSine)
diff --git a/library/pippy/__init__.py b/library/pippy/__init__.py
new file mode 100644
index 0000000..8ddcc7e
--- /dev/null
+++ b/library/pippy/__init__.py
@@ -0,0 +1,9 @@
+"""Pippy standard library."""
+import pippy.console as console
+import pippy.game as pygame
+import pippy.sound as sound
+
+def wait(delay=0.1):
+    """Pause briefly, for animations."""
+    import time
+    time.sleep(delay)
diff --git a/library/pippy/console.py b/library/pippy/console.py
new file mode 100644
index 0000000..cdbb023
--- /dev/null
+++ b/library/pippy/console.py
@@ -0,0 +1,5 @@
+"""Console helpers for pippy."""
+def clear():
+    """Clear screen on console."""
+    # magic escape sequence
+    print '\x1B[H\x1B[J' # clear screen
diff --git a/library/pippy/game.py b/library/pippy/game.py
new file mode 100644
index 0000000..e5996fa
--- /dev/null
+++ b/library/pippy/game.py
@@ -0,0 +1,61 @@
+"""pygame support for pippy."""
+
+import pygame
+
+def pause():
+    # display a "Paused" screen and suspend.
+    caption, icon_caption = pygame.display.get_caption()
+    screen = pygame.display.get_surface()
+    old_screen = screen.copy()  # save this for later.
+
+    # dim the screen and display the 'paused' message in the center.
+    BLACK = (0,0,0)
+    WHITE = (255,255,255)
+    dimmed = screen.copy()
+    dimmed.set_alpha(128)
+    screen.fill(WHITE)
+    screen.blit(dimmed, (0,0))
+    font = pygame.font.Font(None, 36) # 36px high
+    msg = "   PAUSED   "
+    msg_surf = font.render(msg, True, BLACK, WHITE)
+    def center(rect, screen):
+        rect.center = (screen.get_width()/2, screen.get_height()/2)
+    
+    rect = pygame.Rect((0,0),msg_surf.get_size())
+    rect.inflate_ip(rect.width, rect.height)
+    center(rect, screen)
+    screen.fill(WHITE, rect)
+    rect = msg_surf.get_rect()
+    center(rect, screen)
+    screen.blit(msg_surf, rect)
+    pygame.display.flip()
+
+    # SUSPEND
+    try:
+        open('/sys/power/state','w').write('mem')
+    except: # XXX: couldn't suspend (no permissions?)
+        pygame.event.post(pygame.event.wait())
+
+    pygame.display.set_caption(caption, icon_caption)
+    screen.blit(old_screen, (0,0))
+    pygame.display.flip()
+
+_last_event_time=0
+def next_frame(max_fps=20, idle_timeout=20, clock=pygame.time.Clock()):
+    """Limit maximum frame rate of pygame.  Returns True.
+
+    If idle longer than the idle_timeout (in seconds), then we'll put up a
+    "paused" message and the XO will suspend.  This ensures that we don't
+    burn up all of our battery running an animation!"""
+    global _last_event_time
+    clock.tick(max_fps)
+
+    if pygame.event.peek(xrange(pygame.NOEVENT, pygame.USEREVENT)):
+        # we're not idle anymore.
+        _last_event_time = pygame.time.get_ticks()
+    elif (pygame.time.get_ticks() - _last_event_time) >= idle_timeout*1000:
+        # we've been idle for a long time.  Pause & suspend.
+        pause()
+        _last_event_time = pygame.time.get_ticks()
+        
+    return True
diff --git a/sound/sound.py b/library/pippy/sound.py
index b84cbe6..b84cbe6 100755
--- a/sound/sound.py
+++ b/library/pippy/sound.py
diff --git a/sound/__init__.py b/sound/__init__.py
deleted file mode 100644
index e69de29..0000000
--- a/sound/__init__.py
+++ /dev/null