Query

class moderngl.Query

This class represents a Query object.

Create

Context.query(*, samples: bool = False, any_samples: bool = False, time: bool = False, primitives: bool = False) moderngl.query.Query

Create a Query object.

Keyword Arguments
  • samples (bool) – Query GL_SAMPLES_PASSED or not.

  • any_samples (bool) – Query GL_ANY_SAMPLES_PASSED or not.

  • time (bool) – Query GL_TIME_ELAPSED or not.

  • primitives (bool) – Query GL_PRIMITIVES_GENERATED or not.

Attributes

Query.samples

The number of samples passed.

Type

int

Query.primitives

The number of primitives generated.

Type

int

Query.elapsed

The time elapsed in nanoseconds.

Type

int

Query.crender

Can be used in a with statement.

Type

ConditionalRender

Query.extra

Any - Attribute for storing user defined objects

Query.mglo

Internal representation for debug purposes only.

Query.ctx

The context this object belongs to

Examples

Simple query example

 1import moderngl
 2import numpy as np
 3
 4ctx = moderngl.create_standalone_context()
 5prog = ctx.program(
 6    vertex_shader='''
 7        #version 330
 8
 9        in vec2 in_vert;
10
11        void main() {
12            gl_Position = vec4(in_vert, 0.0, 1.0);
13        }
14    ''',
15    fragment_shader='''
16        #version 330
17
18        out vec4 color;
19
20        void main() {
21            color = vec4(1.0, 0.0, 0.0, 1.0);
22        }
23    ''',
24)
25
26vertices = np.array([
27    0.0, 0.0,
28    1.0, 0.0,
29    0.0, 1.0,
30], dtype='f4')
31
32vbo = ctx.buffer(vertices.tobytes())
33vao = ctx.simple_vertex_array(prog, vbo, 'in_vert')
34
35fbo = ctx.simple_framebuffer((64, 64))
36fbo.use()
37
38query = ctx.query(samples=True, time=True)
39
40with query:
41    vao.render()
42
43print('It took %d nanoseconds' % query.elapsed)
44print('to render %d samples' % query.samples)

Output

It took 13529 nanoseconds
to render 496 samples