Sugargame

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 It is fork of olcpgames, which is no longer maintained.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

Get it from:

http://github.com/sugarlabs/sugargame

And place it within your activity source. It is not part of Sugar. Remember to check back for updates when you are continuing development of your activity.

You can find it in some activities already. It is so small that the duplication is unimportant.

Using Sugargame

See also Development Team/Sugargame/Examples.

Wrapping a Pygame program

To use Sugargame to Sugarize a Pygame program, set up an activity directory and copy the Sugargame package to it. For an example, see the directory named test, inside the Sugargame repository. It is a Sugargame activity.

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 must create a single PygameCanvas widget, passing the main loop function of the Pygame program:

import sugargame.canvas
...
    self._canvas = sugargame.canvas.PygameCanvas(self, main=self.game.run)
    self.set_canvas(self._canvas)

The activity may assign keyboard focus to the PygameCanvas widget, so that keyboard events generate Pygame events:

    self._canvas.grab_focus()

In your Pygame main loop, you must pump the GTK event loop:

    while Gtk.events_pending():
        Gtk.main_iteration()

Adding Pygame to a GTK activity

To add Pygame to an existing Sugar activity, create a PygameCanvas widget passing the main loop function of the Pygame program, and the modules to initialise.

    widget = sugargame.canvas.PygameCanvas(self,
        main=self.game.run,
        modules=[pygame.display])

    vbox.pack_start(widget)

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

In the main loop, process GTK events using Gtk.main_iteration().

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

        while self.running:
            # Pump GTK events
            while Gtk.events_pending():
                Gtk.main_iteration()

            # Pump PyGame events
            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    return
                elif event.type == pygame.VIDEORESIZE:
                    pygame.display.set_mode(event.size, pygame.RESIZABLE)

            # Check the mouse position
            x, y = pygame.mouse.get_pos()

            # 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

Sugargame was developed by Wade Brainerd wadetb@gmail.com.

Sugargame was loosely based on the source code to the olpcgames framework, developed by the One Laptop per Child project.

Changelog

v1.3

• Fix initialisation of Gtk.EventBox (James Cameron)
• Port from GObject to GLib (James Cameron)
• Remove pointer_hint from PygameCanvas (James Cameron)
• Add K_KP3 and K_KP5 to event translation table (Aniket Mathur)
• Port to Python 3 (Rahul Bothra)

v1.2

• Port to GTK+ 3 (Manuel Quiñones)
• Add get_preview method (Ignacio Rodríguez)
• Fix startup delay and display resize (James Cameron)
• Fix race condition on fast systems (James Cameron)

v1.1

• Fix bugs in event handling. (Pablo Moleri)
• Remove reference to gtk.Socket.get_window() method, which is missing in older versions of PyGTK.

v1.0

• Initial version of Sugargame

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)