Source Code for Module glitter.contexts.contextmanager

 1  """Tools for managing render contexts. 
 2   
 3  @author: Stephan Wenger 
 4  @date: 2012-03-08 
 5  """ 
 6   
 7 -class ContextBindingProxy(object): 
 8      _bound_context = None 
 9   
10 -    def __get__(self, obj, cls=None): 
11          return self._bound_context 
12   
13 -    def __set__(self, obj, context=None): 
14          if context is None: 
15              self._bound_context = None 
16          elif context != self._bound_context: 
17              self._bound_context = context 
18              context._bind() 
19   
20 -    def __repr__(self): 
21          return "proxy for context binding" 
22   
23 -class ContextManager(object): 
24      current_context = ContextBindingProxy() 
25      """The currently active context.""" 
26   
27 -    def __init__(self): 
28          self._stack = [] 
29   
30 -    def push(self, context): 
31          self._stack.append(self.current_context) 
32          self.current_context = context 
33   
34 -    def pop(self): 
35          self.current_context = self._stack.pop() 
36   
37      @staticmethod 
38 -    def create_default_context(): 
39          """Create a default offscreen rendering context. 
40   
41          @todo: This is window system dependent; create an appropriate context 
42          dynamically. 
43          @todo: When no context exists, create a raw offscreen context instead of a 
44          hidden GLUT window so that rendering is possible without an X connection. 
45          """ 
46   
47          from glitter.contexts.glut import GlutWindow 
48          return GlutWindow(shape=(1, 1), hide=True) 
49   
50  context_manager = ContextManager() 
51   
52  __all__ = ["context_manager"] 
53