import moderngl
import numpy as np
from PIL import Image
ctx = moderngl.create_standalone_context()
prog = ctx.program(
vertex_shader='''
#version 330
in vec2 in_vert;
in vec3 in_color;
out vec3 v_color;
void main() {
v_color = in_color;
gl_Position = vec4(in_vert, 0.0, 1.0);
}
''',
fragment_shader='''
#version 330
in vec3 v_color;
out vec3 f_color;
void main() {
f_color = v_color;
}
''',
)
x = np.linspace(-1.0, 1.0, 50)
y = np.random.rand(50) - 0.5
r = np.ones(50)
g = np.zeros(50)
b = np.zeros(50)
vertices = np.dstack([x, y, r, g, b])
vbo = ctx.buffer(vertices.astype('f4').tobytes())
vao = ctx.simple_vertex_array(prog, vbo, 'in_vert', 'in_color')
fbo = ctx.simple_framebuffer((512, 512))
fbo.use()
fbo.clear(0.0, 0.0, 0.0, 1.0)
vao.render(moderngl.LINE_STRIP)
Image.frombytes('RGB', fbo.size, fbo.read(), 'raw', 'RGB', 0, -1).show()