overlap_rectangle.py

import sys
import numpy as np

from vispy import app, gloo, visuals
from vispy.visuals import transforms

N = 100
n = 10
width = 800
height = 600

positions = np.random.rand(N, 3)
positions[:, 0] *= width
positions[:, 1] *= height
positions[:, 2] = 0
positions = np.floor(positions)


class Canvas(app.Canvas):

    def __init__(self):
        app.Canvas.__init__(self, keys='interactive', size=(800, 800))
        global pos
        self.visuals = []

        for p in positions:
            rect = visuals.RectangleVisual(center=p, height=n,
                                           width=n,
                                           color='white')
            rect.transform = transforms.NullTransform()
            self.visuals.append(rect)
        self.show()

    def on_resize(self, event):
        vp = (0, 0, self.physical_size[0], self.physical_size[1])

        for visual in self.visuals:
            visual.transforms.configure(canvas=self, viewport=vp)

    def on_draw(self, ev):
        gloo.set_clear_color((0, 0, 0, 1))
        gloo.set_viewport(0, 0, *self.physical_size)
        gloo.clear()
        for vis in self.visuals:
            vis.draw()


if __name__ == '__main__':
    win = Canvas()

    if sys.flags.interactive != 1:
        win.app.run()