Save and restore state of the game

Ability to 'save' (when the user closes the Activity) and 'restore' (when the
user launch it from the Journal or the Home without holding Alt) the state of
the game.

For this ability I had to upgrade 'olpcgames' to 1.6 because
'olpcgames.FILE_READ_REQUEST' and 'olpcgames.FILE_WRITE_REQUEST' events are
added in that version and those events are needed for this.

The data is saved (as JSON, with json module) in the 'event.metadata["state"]' and the timestamp state is saved in 'event.filename'.

This commit solves ticket #2393:
 * http://bugs.sugarlabs.org/ticket/2393

Signed-off-by: Manuel Kaufmann <humitos@gmail.com>
Signed-off-by: Rafael Ortiz <rafael@activitycentral.com>

1 files changed, 20 insertions, 5 deletions

diff --git a/olpcgames/svgsprite.py b/olpcgames/svgsprite.py
index 2c53178..ad247dd 100644
--- a/olpcgames/svgsprite.py
+++ b/olpcgames/svgsprite.py
@@ -1,10 +1,16 @@
 """RSVG/Cairo-based rendering of SVG into Pygame Images"""
-from pygame import sprite
+from pygame import sprite, Rect
 from olpcgames import _cairoimage
-import cairo, rsvg
 
 class SVGSprite( sprite.Sprite ):
-    """Sprite class which renders SVG source-code as a Pygame image"""
+    """Sprite class which renders SVG source-code as a Pygame image
+    
+    Note:
+    
+        Currently this sprite class is a bit over-engineered, it gets in the way 
+        if you want to, e.g. animate among a number of SVG drawings, as it 
+        assumes that setSVG will always set a single SVG file for rendering.
+    """
     rect = image = None
     resolution = None
     def __init__( 
@@ -30,7 +36,7 @@ class SVGSprite( sprite.Sprite ):
             width,height = self.size
         else:
             width,height = None,None
-        self.image = self._render( width,height )
+        self.image = self._render( width,height ).convert_alpha()
         rect = self.image.get_rect()
         if self.rect:
             rect.move( self.rect ) # should let something higher-level do that...
@@ -38,6 +44,7 @@ class SVGSprite( sprite.Sprite ):
 
     def _render( self, width, height ):
         """Render our SVG to a Pygame image"""
+        import rsvg
         handle = rsvg.Handle( data = self.svg )
         originalSize = (width,height)
         scale = 1.0
@@ -66,4 +73,12 @@ class SVGSprite( sprite.Sprite ):
             handle.render_cairo( ctx )
             return _cairoimage.asImage( csrf )
         return None
-    
+    def copy( self ):
+        """Create a copy of this sprite without reloading the svg image"""
+        result = self.__class__(
+            size = self.size
+        )
+        result.image = self.image 
+        result.rect = Rect(self.rect)
+        result.resolution = self.resolution
+        return result