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Perfect Circle

neal.fun

51–60 of 155 posts

Re: Perfect Circle

#51
post #32
post #26

By cheating with a Python script to move the mouse, I managed to get 99.9%. Seems difficult to get higher than that, perhaps due to the mouse position having integer coordinates.

A mac or windows app controlling the mouse I presume?

Arduino controlling a robotic arm holding a mouse, written in C.

Re: Perfect Circle

#53
post #20

Hey this is so well done! You know, you could put the sun on one of the the two focii and ask the user to draw the elliptical orbit of the earth - perfect real-life usecase.

[deleted]

Re: Perfect Circle

#54
post #34

An even better challenge: try to draw the least circle-like thing. It is surprisingly hard!

Interestingly it will stop you if you start to go the “wrong” way. Without looking at the source code, I’m wondering if it is keeping a convex hull to determine this?

Re: Perfect Circle

#55
I thought this was about Giotto a famous Renaissance Painter, but it seems to be a training app, to become like him (one day):

"The Pope hoped to hire a fresco artist and sent to Giotto a messenger, who asked for a competitive sample drawing. With just paper and a pen, Giotto flicked his wrist and drew a perfect circle. Vasari writes: "The messenger, seeing that he could get nothing else, departed ill-pleased...However, sending the other drawings to the Pope with the names of those who had made them, he sent also Giotto's, relating how he had made the circle without moving his arm and without compasses; the Pope…saw that Giotto must surpass greatly all the other painters of his time."

https://www.smithsonianmag.com/arts-culture/perfect-circles-...

Re: Perfect Circle

#57
post #47
post #44

Earlier quoted context omitted.

In a similar vein, people claim it's impossible to draw a heptagon with a straight edge and ruler. Sure, but good luck pulling of a perfect octagon either, given the limitations of pen and paper. And there's a perfectly good approximation that'll very quickly produce a theoretical heptagon with error margins less than the thickness of a pencil. 1/7 ~= 1/8 + 1/64 + 1/512 + 1/4096 (1/n = sum(1...infinity) of 1/((n + 1)…

Octagons are great fun to draw on graph paper. They're just a truncated square.

They are! But the octagons you draw that way aren’t regular (basically because sqrt(2) is irrational)

Re: Perfect Circle

#58
post #47
post #44

Earlier quoted context omitted.

In a similar vein, people claim it's impossible to draw a heptagon with a straight edge and ruler. Sure, but good luck pulling of a perfect octagon either, given the limitations of pen and paper. And there's a perfectly good approximation that'll very quickly produce a theoretical heptagon with error margins less than the thickness of a pencil. 1/7 ~= 1/8 + 1/64 + 1/512 + 1/4096 (1/n = sum(1...infinity) of 1/((n + 1)…

Octagons are great fun to draw on graph paper. They're just a truncated square.

If you draw the diagonal sides as the diagonals of squares, they will have the square root of two times the length of the vertical or horizontal sides.
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