1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
|
# -*- coding: utf-8 -*-
# -----------------------------------------------------------------------------
# Copyright (c) Vispy Development Team. All Rights Reserved.
# Distributed under the (new) BSD License. See LICENSE.txt for more info.
# -----------------------------------------------------------------------------
from .wrappers import read_pixels
def _screenshot(viewport=None, alpha=True):
"""Take a screenshot using glReadPixels. Not sure where to put this
yet, so a private function for now. Used in make.py.
Parameters
----------
viewport : array-like | None
4-element list of x, y, w, h parameters. If None (default),
the current GL viewport will be queried and used.
alpha : bool
If True (default), the returned array has 4 elements (RGBA).
Otherwise, it has 3 (RGB)
Returns
-------
pixels : array
3D array of pixels in np.uint8 format
"""
# gl.glReadBuffer(gl.GL_BACK) Not avaliable in ES 2.0
return read_pixels(viewport, alpha)
KEYWORDS = set(['active', 'asm', 'cast', 'class', 'common', 'default',
'double', 'dvec2', 'dvec3', 'dvec4', 'enum', 'extern',
'external', 'filter', 'fixed', 'flat', 'fvec2', 'fvec3',
'fvec4', 'goto', 'half', 'hvec2', 'hvec3', 'hvec4', 'iimage1D',
'iimage1DArray', 'iimage2D', 'iimage2DArray', 'iimage3D',
'iimageBuffer', 'iimageCube', 'image1D', 'image1DArray',
'image1DArrayShadow', 'image1DShadow', 'image2D',
'image2DArray', 'image2DArrayShadow', 'image2DShadow',
'image3D', 'imageBuffer', 'imageCube', 'inline', 'input',
'interface', 'long', 'namespace', 'noinline', 'output',
'packed', 'partition', 'public', 'row_major', 'sampler1D',
'sampler1DShadow', 'sampler2DRect', 'sampler2DRectShadow',
'sampler2DShadow', 'sampler3D', 'sampler3DRect', 'short',
'sizeof', 'static', 'superp', 'switch', 'template', 'this',
'typedef', 'uimage1D', 'uimage1DArray', 'uimage2D',
'uimage2DArray', 'uimage3D', 'uimageBuffer', 'uimageCube',
'union', 'unsigned', 'using', 'volatile'])
def check_variable(name):
"""
Return None if *name* is expected to be a valid variable name in any GLSL
version. Otherwise, return a string describing the problem.
"""
# Limit imposed by glGetActive* in pyopengl
if len(name) > 31:
return ("Variable names >31 characters may not function on some "
"systems.")
return check_identifier(name)
def check_identifier(name):
if '__' in name:
return "Identifiers may not contain double-underscores."
if name[:3] == 'gl_' or name[:3] == 'GL_':
return "Identifiers may not begin with gl_ or GL_."
if name in KEYWORDS:
return "Identifier is a reserved keyword."
def check_enum(enum, name=None, valid=None):
"""Get lowercase string representation of enum."""
name = name or 'enum'
# Try to convert
res = None
if isinstance(enum, int):
if hasattr(enum, 'name') and enum.name.startswith('GL_'):
res = enum.name[3:].lower()
elif isinstance(enum, str):
res = enum.lower()
# Check
if res is None:
raise ValueError('Could not determine string representation for'
'enum %r' % enum)
elif valid and res not in valid:
raise ValueError('Value of %s must be one of %r, not %r' %
(name, valid, enum))
return res
vert_draw = """
attribute vec2 a_position;
attribute vec2 a_texcoord;
varying vec2 v_uv;
void main(void) {
v_uv = a_texcoord.xy;
gl_Position = vec4(a_position, 0., 1.);
}
"""
frag_draw = """
uniform sampler2D u_texture;
varying vec2 v_uv;
void main(void) {
gl_FragColor = texture2D(u_texture, v_uv).rgba;
}
"""
def draw_texture(tex):
"""Draw a 2D texture to the current viewport
Parameters
----------
tex : instance of Texture2D
The texture to draw.
"""
from .program import Program
program = Program(vert_draw, frag_draw)
program['u_texture'] = tex
program['a_position'] = [[-1., -1.], [-1., 1.], [1., -1.], [1., 1.]]
program['a_texcoord'] = [[0., 1.], [0., 0.], [1., 1.], [1., 0.]]
program.draw('triangle_strip')
|
