Activity Team/Sugar-sprites

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Sugar sprites library

While not yet an official part of Sugar, there is a simple sprites library, sprites.py, that is used by many activities, including Turtle Art, Visual Match, Slideruler, Cardsort, Erikos, etc.

sprites.py is a simple sprites library for managing graphics objects, 'sprites', on a canvas. It manages multiple sprites with methods such as move, hide, set_layer, etc.

There are two classes:

  • class Sprites maintains a collection of sprites.
  • class Sprite manages individual sprites within the collection.

Example usage

The basic work flow is to first create a Sprites instance to manage the sprite collection. Then create and use individual sprites.

       # Import the classes into your program.
       from sprites import Sprites, Sprite
       # Create a new sprite collection for a gtk Drawing Area.
       my_drawing_area = gtk.DrawingArea()
       self.sprite_list = Sprites(my_drawing_area)
       # Create a "pixbuf" (in this example, from SVG).
       my_pixbuf = svg_str_to_pixbuf("<svg>...some svg code...</svg>")
       # Create a sprite at position x1, y1.
       my_sprite = sprites.Sprite(self.sprite_list, x1, y1, my_pixbuf)
       # Move the sprite to a new position.
       my_sprite.move((x1+dx, y1+dy))
       # Create another "pixbuf".
       your_pixbuf = svg_str_to_pixbuf("<svg>...some svg code...</svg>")
       # Create a sprite at position x2, y2.
       your_sprite = sprites.Sprite(self.sprite_list, x2, y2, my_pixbuf)
       # Assign the sprites to layers.
       # In this example, your_sprite will be on top of my_sprite.
       my_sprite.set_layer(100)
       your_sprite.set_layer(200)
       # Now put my_sprite on top of your_sprite.
       my_sprite.set_layer(300)
# method for converting SVG to a gtk pixbuf
def svg_str_to_pixbuf(svg_string):
    pl = gtk.gdk.PixbufLoader('svg')
    pl.write(svg_string)
    pl.close()
    pixbuf = pl.get_pixbuf()
    return pixbuf

The Sprites Class

class Sprites

methods:

   def __init__(self, canvas, area=None, gc=None)
       self.canvas
       self.area
       self.gc
       self.cm
       self.list = []
   def get_sprite(self, i)
   def length_of_list(self)
   def append_to_list(self, spr)
   def insert_in_list(self, spr, i)
   def remove_from_list(self, spr):
   def find_sprite(self, pos):
   def redraw_sprites(self):

The Sprite Class

class Sprite

methods:

   def __init__(self, sprites, x, y, image):
       self.layer = 100
       self.labels = []
       self.images = []
   def set_image(self, image, i=0, dx=0, dy=0):
   def move(self, pos):
   def move_relative(self, pos):
   def get_xy(self):
   def get_dimensions(self):
   def get_layer(self):
   def set_shape(self, image, i=0):
   def set_layer(self, layer):
   def set_label(self, new_label, i=0):
   def set_margins(self, l=0, t=0, r=0, b=0):
   def set_font(self, font):t)
   def set_label_color(self, rgb):
   def set_label_attributes(self, scale, rescale=True, horiz_align="center",
                            vert_align="middle", i=0):
   def hide(self):
   def inval(self):
   def draw(self):
   def hit(self, pos):
   def draw_label(self):
   def label_width(self):
   def label_safe_width(self):
   
   def label_safe_height(self):
   
   def label_left_top(self):
   def get_pixel(self, pos, i=0):