Ok that's pretty badass - I gave it a try with sparklers last winter, as people tend to do - didn't go well haha, but still looked cool. This on the other hand looks like a genuine portal or something.
Can you, in principle, go beyond simple circles but more complex images by way of moving the camera around a track or something?
More complex shapes become difficult, as already described in the previous posts.
https://ecency.com/hive-194913/@candelart/light-painting-in-daylight-without?referral=candelart
The reflection of the sunlight on the mirror must always hit the lens exactly. With a lot of practice, other forms can also be created.
With normal light painting with lamps in the dark you have more options.