As a tip: what it's really checking is for a circle centered on the dot in the middle with the radius equal to your initial click's distance from the center. You could make a mid sized perfect circle which is slightly off the center of the dot and lose to a square that fills the play area.
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.
Cool! Not to self-promote (no monetization or anything), but in case any one finds it helpful, I made something similar for myself to practice becoming more accurate with Wacom-style tablet pens: <a href="https://tabletpractice.arkt.is/" rel="nofollow">https://tabletpractice.arkt.is/</a>
I messed around with building something similar just before the holidays: <a href="https://steadyhand.app/" rel="nofollow">https://steadyhand.app/</a><p>It was a blast to learn how to do things in canvas and as an exercise, a very fun little app to build. I'm not sure how the OP is measuring perfection of the circle, but in mine it was standard deviation of every drawn point around the centre of the page.<p>I encourage people to try to scaffold something like this together in canvas/JS sometime. Very fun project!
Here's the bookmarklet you've been waiting for...<p><pre><code> javascript:(function()%7Blet%20s%3Ddocument.querySelector(%22main%20svg%22).getBoundingClientRect()%2Ccx%3Ds.width%2F2%2Bs.x%2Ccy%3Ds.height%2F2%2Bs.y%2Cr%3Ds.width%2F3%2Cd%3Ddocument.querySelector(%22main%20div%22)%2Ca%3D0%3Bfor(let%20e%3D0%3Be%3C50%3Be%2B%2B)%7Ba%2B%3DMath.acos(1-Math.pow(60%2Fr%2C2)%2F2)%3Blet%20t%3DMath.round(cx%2Br*Math.cos(a))%2Cn%3DMath.round(cy%2Br*Math.sin(a))%3B0%3D%3De%26%26d.dispatchEvent(new%20MouseEvent(%22mousedown%22%2C%7BclientX%3At%2CclientY%3An%7D))%2Cd.dispatchEvent(new%20MouseEvent(%22mousemove%22%2C%7BclientX%3At%2CclientY%3An%7D))%7Dd.dispatchEvent(new%20MouseEvent(%22mouseup%22))%7D)()</code></pre>
Another great neal.fun page. One feature I'd like to see is, make the user to N circles in a row and take the median score or something. Right now you can just spam hundreds and take your top score, but it doesn't really reward consistency.
I thought this was about Giotto a famous Renaissance Painter, but it seems to be a training app, to become like him (one day):<p>"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."<p><a href="https://www.smithsonianmag.com/arts-culture/perfect-circles-180940946/" rel="nofollow">https://www.smithsonianmag.com/arts-culture/perfect-circles-...</a>
This is fun and had a high potential for giving me some repetitive strain injury. My highest score of 97.1 doesn't visually feel like the best circle I've drawn though.
Reminds me of a side project of mine called “Imperfect Circle” which makes asymmetric swung beats<p><a href="https://circle.jminjie.com/" rel="nofollow">https://circle.jminjie.com/</a>
One of my maths teachers was able to draw up to something like a three foot circle on the blackboard that looked very, very close to ideal every time. He would always use two arcs to do it and it was uncanny. He would whip out a metre/yard rule to do straight lines because they are much harder to do.<p>Your limbs etc are all a collection of ball and socket/downright weirdly jointed/hinges with benefits/more weirdness. You then want to use this monstrose agglomeration (did I mention how you move the bloody things?) to draw a circle? Obviously you would decide to run a finger over a simulator of a lump with a ball in it and some on/off switches.<p>People are weird. Nice website though.
"Too slow"<p>"Too slow"<p>"Too slow"<p>OK, this is clearly not meant for trackpads. I can see how I might do it reasonably in the given time with a mouse or on a tablet... but not on my laptop trackpad!! :S
I learned that the best way to do this is to first draw a head, and then erase all the bits that aren't a perfect circle. I didn't see that as an option.<p>EDIT:<p>For those who don't know the reference: <a href="https://youtu.be/wmqsk1vZSKw" rel="nofollow">https://youtu.be/wmqsk1vZSKw</a>
Fun, but needs more rewards than just a high score. Maybe something like a consecutive streak above 90%? Or a challenge where you need to target a given radius. Anyway, nice job.<p>(I recall how my senior hugh school maths teacher was wizz at drawing circles, lines and other geometry on the chalkboard)
I wonder if you could use this technique for drawing perfect circles to get a 100% score on an iPad: <a href="https://www.youtube.com/watch?v=l5WLMPCkpUA">https://www.youtube.com/watch?v=l5WLMPCkpUA</a>
You can get an artifically high score by finishing the last 90 degrees or so with a straight line segment, FYI. I can usually break 90% with something that doesn't resemble a circle very much at all.
Try to keep the radius as small as it lets you. Move very slowly, you'll likely be too slowly the first few tries but find the slowest speed possible. I got 97.3% with a mouse doing this.
My circle is 94.2% perfect, can you beat that? <a href="https://neal.fun/perfect-circle/" rel="nofollow">https://neal.fun/perfect-circle/</a>
My circle is 97.6% perfect, can you beat that? <a href="https://neal.fun/perfect-circle/" rel="nofollow">https://neal.fun/perfect-circle/</a><p>(Now my hand hurts...)
My circle is 89.4% perfect, can you beat that? <a href="https://neal.fun/perfect-circle/" rel="nofollow">https://neal.fun/perfect-circle/</a>
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.
This was fun! It seems like the faster I go, the better the median score gets. My finger on a phone beat my vertical mouse (as I expected), but not by much: 95.8% vs 93.5%.
I kind of have the shakes? <a href="https://imgur.com/a/M1KsWci" rel="nofollow">https://imgur.com/a/M1KsWci</a>