Source Code for Module glitter.arrays.arraybuffer

 1  """Array buffer class. 
 2   
 3  @todo: Implement slicing to allow for C{glVertexAttribPointer} with C{size}, C{stride}, and C{pointer} parameters. 
 4   
 5  @author: Stephan Wenger 
 6  @date: 2012-02-29 
 7  """ 
 8   
 9  import numpy as _np 
10   
11  import glitter.raw as _gl 
12  from glitter.utils import buffer_dimensions_to_primitive, primitive_to_buffer_dimensions 
13  from glitter.arrays.basebuffer import BaseBuffer 
14   
15 -class ArrayBuffer(BaseBuffer): 
16      _binding = "array_buffer_binding" 
17      _target = _gl.GL_ARRAY_BUFFER 
18   
19 -    def _use(self, index, num_components=None, stride=0, first=0): 
20          if num_components is None: 
21              if len(self.shape) == 1: 
22                  num_components = 1 
23              elif 1 <= self.shape[-1] <= 4: 
24                  num_components = self.shape[-1] 
25              else: 
26                  raise ValueError("must specify num_components") 
27          if self.dtype.is_float(): 
28              with self: 
29                  _gl.glVertexAttribPointer(index, num_components, self.dtype._as_gl(), _gl.GL_FALSE, stride * self.dtype.nbytes, first * self.dtype.nbytes) 
30          else: 
31              with self: 
32                  _gl.glVertexAttribIPointer(index, num_components, self.dtype._as_gl(), stride * self.dtype.nbytes, first * self.dtype.nbytes) 
33   
34 -    def draw(self, mode=None, count=None, first=0, instances=None): 
35          if mode is None: 
36              if len(self.shape) > 2: 
37                  mode = buffer_dimensions_to_primitive.get(self.shape[1], None) 
38              else: 
39                  mode = buffer_dimensions_to_primitive.get(1, None) 
40          if mode is None: 
41              raise ValueError("must specify mode") 
42   
43          if count is None: 
44              dim = primitive_to_buffer_dimensions.get(mode, None) 
45              if dim is not None and len(self.shape) > 2 and self.shape[-2] != dim: 
46                  raise ValueError("buffer shape does not match mode") 
47              count = _np.prod(self.shape[:-1]) 
48           
49          if instances is None: 
50              with self: 
51                  _gl.glDrawArrays(mode._value, first, count) 
52          else: 
53              with self: 
54                  _gl.glDrawArraysInstances(mode._value, first, count, instances) 
55   
56  __all__ = ["ArrayBuffer"] 
57