imagearc() draws an arc of circle centered at the given coordinates.
image
An image resource, returned by one of the image creation functions, such as imagecreatetruecolor().
cx
x-coordinate of the center
cy
y-coordinate of the center
width
The arc width
height
The arc height
start
The arc start angle, in degrees.
end
The arc end angle, in degrees. 0° is located at the three-o'clock position, and the arc is drawn clockwise.
color
A color identifier created with imagecolorallocate()