Source Code for Module glitter.arrays.vertexarray

 1  """Vertex array class. 
 2   
 3  @todo: Rethink vertex array drawing: e.g., differing number of elements in vertex and color buffer, allow for use of C{glVertexAttribDivisor}. 
 4   
 5  @author: Stephan Wenger 
 6  @date: 2012-02-29 
 7  """ 
 8   
 9  import glitter.raw as _gl 
10  from glitter.utils import ManagedObject, BindableObject 
11  from glitter.arrays.arraybuffer import ArrayBuffer 
12  from glitter.arrays.elementarray import ElementArrayBuffer 
13   
14 -class VertexArray(ManagedObject, BindableObject): 
15      _generate_id = _gl.glGenVertexArrays 
16      _delete_id = _gl.glDeleteVertexArrays 
17      _db = "vertex_arrays" 
18      _binding = "vertex_array_binding" 
19   
20 -    def __init__(self, *attributes, **kwargs): 
21          """Create a new vertex array. 
22   
23          @param attributes: Buffers to bind to vertex attributes. 
24          @type attributes: C{list} of L{ArrayBuffer}s or C{numpy.ndarray}s 
25          @param kwargs: Named arguments. 
26          @type kwargs: C{dict} 
27          @keyword context: The context in which to create the vertex array. 
28          @type context: L{Context} 
29          @keyword elements: A buffer containing the element indices. 
30          @type elements: L{ElementArrayBuffer} or C{numpy.ndarray} 
31          """ 
32   
33          super(VertexArray, self).__init__(context=kwargs.pop("context", None)) 
34          self._attributes = {} 
35   
36          if isinstance(attributes, dict): 
37              attributes = dict(attributes) 
38          else: 
39              attributes = dict(enumerate(attributes)) 
40          for i in range(self._context.max_vertex_attribs): 
41              self[i] = attributes.pop(i, None) 
42          if attributes: 
43              raise ValueError("vertex array has no attribute(s) %s" % ", ".join("'%s'" % x for x in attributes.keys())) 
44           
45          self.elements = kwargs.pop("elements", None) 
46   
47          if kwargs: 
48              raise TypeError("__init__() got an unexpected keyword argument '%s'" % kwargs.keys()[0]) 
49   
50 -    def __getitem__(self, index): 
51          return self._attributes[index] 
52   
53 -    def __setitem__(self, index, value): 
54          if value is None: 
55              with self: 
56                  _gl.glVertexAttribPointer(index, 4, _gl.GL_FLOAT, _gl.GL_FALSE, 0, _gl.POINTER(_gl.GLvoid)()) 
57                  _gl.glDisableVertexAttribArray(index) 
58          else: 
59              if not isinstance(value, ArrayBuffer): 
60                  value = ArrayBuffer(value, context=self._context) 
61              with self: 
62                  with value: 
63                      value._use(index) 
64                  _gl.glEnableVertexAttribArray(index) 
65          self._attributes[index] = value 
66   
67 -    def __delitem__(self, index): 
68          self[index] = None 
69   
70      @property 
71 -    def elements(self): 
72          return self._elements 
73   
74      @elements.setter 
75 -    def elements(self, elements): 
76          if elements is not None and not isinstance(elements, ElementArrayBuffer): 
77              elements = ElementArrayBuffer(elements, context=self._context) 
78          with self: 
79              self._context.element_array_buffer_binding = elements 
80          self._elements = elements 
81   
82      @elements.deleter 
83 -    def elements(self): 
84          self.elements = None 
85   
86 -    def draw(self, mode=None, count=None, first=0, instances=None, index=None): 
87          with self: 
88              if index is None: 
89                  if self.elements is not None: 
90                      self.elements.draw(mode, count, first, instances) 
91                  else: 
92                      min(x for x in self._attributes.items() if x[1] is not None)[1].draw(mode, count, first, instances) 
93              else: 
94                  self[index].draw(mode, count, first, instances) 
95   
96  __all__ = ["VertexArray"] 
97