Hello

 

Has anyone else noticed that ms paint makes circles wrong at some sizes? They arn't very symmetrical at certin sizes. For example if you make a circle without an outline just the inside colored you get a huge mess with sizes like 18x18.

That's what i mean. Notice the edges are wrong on the left side!

Edited by Pixel_Outlaw

Well I would inform Microsoft but I doubt they care.

The program I use for pixelling also messes up with circles often...
I'm not all that good at making circles completely by hand, so I always first make a circle using the circle tool and then clean it up, make it symmetrical etc.

adobe photshop

That's a flaw on the Windows API to draw circles, so using other programs are hardly going to help, since they all tend to use the same API (even Photoshop). Anti-aliasing is another case, so not relevant here. Also, a filled circle and a countour circle all work the same way.

Mathematically speaking, the problem lies on the fact that a good programmer would have coded it using the floor function and drawing only 1/4 of the circle and then mirroring the rest. (that CAD stuff you said is kinda nonsense) This is the most effective way, and the floor function is MATHEMATICALLY CORRECT to deal with the aliasing of the circle points. (the circle has infinite detail, you have to represent it in pixels that have finite frequency, hence you gotta represent infinite information on a finite way)

But on WinXP they decided to draw it using the round* function, and drawing the whole circle instead of only 1/4. The floating point fluctuations are usually not a problem, but since they're using round they are maximized, and since they are not mirroring, they're inconsistent and create assymetrical circles.

There's nothing you can do about it though, except using WinMe or older. So, all you can really do is just draw the circle and correct it yourself.

* Yes they used round. I can easily tell because of the behavior of the pixels when you make a wide ellipse. Open MS paint, zoom in and use the circle tool. Draw a circle of 49x27 (note that this number is incorrect in MS Paint, 1 pixel in excess in both axis), then still holding the mouse, move it to the right to make it 50x27. See how the left size pops out abruptly? That's because of the round function.

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And since this sucks so much ass, that's why I coded my own circle-making program to output (usually bigger), symmetrical circles in BMP form so I can use. Ha-hah, I feel bad for having to be so drastical. f**k it.

Edited by 1ucas

I usually make circles by hand.. I know that Paint skrews in many things but at least it is simple-functioned and not overflooded with useless functions. I love Paint!

Hrmmmm... A pirate has a mojor advantsge, using his peg leg as a centering point and placing the pencil in his toes, he need only pivot on his hips to draw a perfect circle. A pirate compass if you will!