Development Team/Sugargame

Sugargame

Sugargame is a Python package which allows Pygame programs to run well under Sugar. It is fork of the olcpgames framework, which is no longer maintained.

What it does:

• Wraps a Sugar activity around an existing Pygame program with few changes
• Allows Sugar toolbars and other widgets to be added to the activity UI
• Provides hooks for saving to and restoring from the Journal

Differences between Sugargame and olpcgames

The olpcgames framework provides a wrapper around Pygame which attempts to allow a Pygame program to run mostly unmodified under Sugar. To this end, the Pygame program is run in a separate thread with its own Pygame message loop while the main thread runs the GTK message loop. Also, olpcgames wraps Sugar APIs such as the journal and mesh into a Pygame-like API.

Sugargame takes a simpler approach; it provides a way to embed Pygame into a GTK widget. The Sugar APIs are used to interact with Sugar, the Pygame APIs are used for the game.

Sugargame advantages:

• Simpler code
• More elegant interface between Pygame and GTK
• Runs as a single thread: no thread related segfaults
• Possible to use Sugar widgets with Pygame

Sugargame limitations:

• No support for Pango or SVG sprites (yet)

Using Sugargame

Wrapping a Pygame program

To use Sugargame to Sugarize a Pygame program, set up an activity directory and copy the Sugargame package to it.

The activity directory should look something like this:

  activity/            - Activity directory: activity.info, SVG icon, etc.
  sugargame/           - Sugargame package
  MyActivity.py        - Activity class
  mygame.py            - Pygame code
  setup.py             - Install script

To make the Activity class, start with test/TestActivity.py from the Sugargame distribution.

The activity should create a single PygameCanvas widget and call run_pygame on it. Pass the main loop function of the Pygame program.

self._canvas = sugargame.canvas.PygameCanvas(self)
self.set_canvas(self._canvas)
       
# Start the game running.
self._canvas.run_pygame(self.game.run)

In your Pygame main loop, pump the GTK message loop:

  while gtk.events_pending():
      gtk.main_iteration()

Adding Pygame to a PyGTK activity

To add Pygame to an existing Sugar activity, create a PygameCanvas widget and call run_pygame on it.

widget = sugargame.canvas.PygameCanvas(self)
vbox.pack_start(widget)

widget.run_pygame(self.game.run)

Due to limitations of Pygame and SDL, there can only be one PygameCanvas in the entire activity.

The argument to run_pygame is a function structured like a Pygame program. In the main loop, remember to dispatch GTK messages using gtk.main_iteration().

def main_loop():
       clock = pygame.time.Clock()
       screen = pygame.display.get_surface()

       while self.running:
           # Pump GTK messages.
           while gtk.events_pending():
               gtk.main_iteration()

           # Pump PyGame messages.
           for event in pygame.event.get():
               if event.type == pygame.QUIT:
                   return

           # Clear Display
           screen.fill((255,255,255)) #255 for white

           # Draw stuff here
           .................

           # Flip Display
           pygame.display.flip()  
            
           # Try to stay at 30 FPS
           self.clock.tick(30)

Support

For help with Sugargame, please email the Sugar Labs development list:

sugar-devel@lists.sugarlabs.org

Author

Sugargame is developed by Wade Brainerd <wadetb@gmail.com>.

It is loosely based on the source code to the olpcgames framework, developed by the One Laptop Per Child project.