Draw a circle in a matrix / image

Draw a circle in a 2D matrix using the integer midpoint circle algorithm

Description

This is a good example of the integer midpoint circle algorithm. No pixels are missed or repeated.

• MATLAB release: MATLAB 7.3 (R2006b)

[dave martin]

Boring.

[Urs (us) Schwarz]

the fact that the reviewer below finds the submission boring is not substantial and certainly does not warrant a poor rating by itself. please, be more considerate.
to the author: the function could be spruced up a bit, eg, an x/y-offset option
us

[John Jorsett]

Just what I was looking for and not "boring" at all.

[Huan Tan]

agreed! every little tool like this can find its place. very helpful, just what i was looking for

[Mustafa Sami]

 

[sorry sorry]

i hope if one till me how to use it, can one tell us i, value stand for what....

[Tom Canty]

Comments in your code isnt just for coding class, it helps others understand your code

[Ellen Blinka]

When I ran the code, there were some skipped pixels in the drawn circle.

[Sheila Geva]

Hi,
I need to draw circles in each cell in an intensity matrix that I'm printing. How do I use your code to do so?
Also, I don't understand the parameters that need to be put in the function. Please explain?

[John Doe]

Excellent, clean implementation. This is the first of over a dozen submissions I've seen that actually uses this algorithm (and they all should). Very nice. Commenting your code would be a nice touch, however...

[Andrew Harward]

It is simple to modify this function to allow circles of both odd & even size (currently the algorithm cannot produce even sized e.g. 8x8 circles). Maybe I'll post up a modified version if that's OK with you?

[Matthew]

Can someone fill me in as to how this code works. Also, can it be altered to make an annulus as opposed to just a circle?

[Nor Muzakkir]

got it working.

i = the pixel value for coordinate (1,1).
radius = radius of the circle.
xc and yc = center coordinate of the circle.
value = the pixel value for the circle.

extra note: the value for xc and yc must be larger than radius.

thanks author, i've been searching for this kind of function.

[chitra s]

what value i have to give for the parameter 'value'?

[William Lau Kai Wei]

this is a coding to draw a circle.
i using the same code but i looping it with reduce the radius.

let say, my radius is 7, I try looping it by draw radius with 7, and then 6, and then 5 and so on until it become 0. It really fill in a lot of space but the problem is still got some space is empty.

My problem now is I want to fill in all the area inside the circle. So, any idea to solve this problem? Thank you

[Ibtissem Labed]

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