Sweet QGIS moves

.py

from datetime import datetime, timedelta
from time import sleep
from typing import Tuple

import numpy as np


def coords8(size: int, nb_points: int = 100) -> Tuple[int, int]:
    t = np.linspace(0, 2 * np.pi, nb_points)
    x = size * np.sin(t)
    y = size * np.cos(t) / 2
    return x, y


class SweetMovesTask(QgsTask):
    def __init__(
        self,
        description: str,
        iface: QgisInterface,
        duration: float = 3,
        refresh: float = 0.1,
        size: int = 500,
        nb_points: int = 20,
    ):
        super().__init__(description, QgsTask.CanCancel)
        self.iface = iface
        self.duration = duration
        self.refresh = refresh
        self.size = size
        self.nb_points = nb_points

    def run(self) -> bool:
        start_time = datetime.now()
        stop_time = start_time + timedelta(seconds=self.duration)
        canvas = iface.mapCanvas()
        center = canvas.center()
        cx, cy = center.x(), center.y()
        coords = coords8(self.size, self.nb_points)
        i = 0
        up = True
        while datetime.now() < stop_time:
            self.setProgress(
                ((datetime.now() - start_time).total_seconds()) / self.duration * 100
            )
            if self.isCanceled():
                return False
            nx, ny = coords[0][i], coords[1][i]
            dx, dy = nx - cx, ny - cy
            rect = canvas.sceneRect()
            rect.moveTo(dx, dy)
            canvas.setSceneRect(rect)
            sleep(self.refresh)
            cx = nx
            cy = ny
            if up:
                i += 1
                if i >= self.nb_points - 1:
                    up = False
            else:
                i -= 1
                if i <= 0:
                    up = True
        return True


task = SweetMovesTask(
    "Sweet moves",
    iface,
    duration=5,
    refresh=0.05,
    size=333,
    nb_points=20,
)
QgsApplication.taskManager().addTask(task)