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.
Might have something to do with the mechanics of your shoulder. Particularly if your hand is in the air, counterclockwise feels more natural than clockwise. Or at least, for your right arm.
What happens if you repeat the experiment with your left hand?
This explains why I'm able to achieve my lowest ever score (0.7%) by starting a sort of spiral shape near the dot, whereas drawing that spiral in reverse would be much closer to perfect (>85%).
This is what I aimed for since that is how a circle is defined in a cartesian equation: (x − a)^2 + (y − b)^2 = r^2 where a and b are the circle’s center point xy coordinates and r is radius.
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.
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.
Fair enough. But you can get pretty close if you draw a 10x10 with 4 squares on the sides parallel to the graph. Or 5x5 with 3 on each side. The former is 6% over and the latter 6% under. And if you go juust a hair outside of the lines you're dead on. Such as a pencil tip's width off of the ruler.
I just worked that out with a calculator, but I'm fairly sure I worked that out empirically while bored in math class one year. My very wise teacher put me and the other bored kid way to the opposite side of the classroom from where his chalkboard was and looked the other way when we played 'squares' in class, safely out of the peripheral vision of any of the other kids. Probably the only time I ever dared 'pass notes' in class.
You can get pretty close with a pencil and a ruler though, if you have the right diameter of mechanical pencil. If you place the ruler dead on the corners of the squares and draw the line offset that tiny little bit, the error is barely perceptible without magnification.
I used the pyautogui library on Linux. Then just a simple loop with an incrementing angle, with some overshoot in the end in order for the webpage to recognize that the circle was complete. First time using the library, worked pretty well, except I had to figure out that I had to use pyautogui.PAUSE = 0 to make it not pause between mouse movements.
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: https://tabletpractice.arkt.is/
I messed around with building something similar just before the holidays: https://steadyhand.app/
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.
I encourage people to try to scaffold something like this together in canvas/JS sometime. Very fun project!
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.
That challenge was surprisingly hard. Even with the couple of landmarks (I think a few small bushes). It’s weird how high the difference was between what looked like a perfect circle and what was actually expected. It was almost like an optical illusion.
I got 100% (the second moon) purely by the feel of the controller. I didn’t even look. I just started an arc and held fast. It’s amazingly difficult to walk a perfect circle.
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."
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.
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.
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.
My middle school maths teacher (awesome guy, also had a mustache - mid 90s) taught us how to draw (large) circles on blackboards easily:
Start from the bottom and go counter-clockwise full circle having your arm fully extended. After the first couple of tries, when you build up confidence through the results, the circles get very good. The trick is not moving slowly, but doing it in one go.
The 3'/two ark circles he would do the same way, but using the elbow as the central/pivot point instead of the shoulder.
I am imagining I somehow have a hidden wire up my sleeve creating the radial tension for a perfect circle
Fishing line attached to a collar around my shoulder could could work
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On a completely different note, in grade school I figured out you can tie fishing line to a pencil and wait for someone to try picking it up. Then give a little jerk so it moves 10 inches or so
People react wildly differently when they suddenly see behavior their mind cannot process! One math teacher walking around the back of class literally jumped up and a gave out a loud “Ieeeyaaa!” shout.
We can react to something much faster than we can think it through
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.
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.
(I recall how my senior hugh school maths teacher was wizz at drawing circles, lines and other geometry on the chalkboard)
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.
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%.
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?
