How do you plot a 3D circle segment?

It seems very straightforward to plot 3D polygons using fill3, however instead of a polygon is there a way to plot a circle segment?

Say we have 3 points in space, which represent the centre of the circle and two points on it's circumference, how can I draw the filled arc segment between these two points?

Answer 1

[Cindy Solomon]

Hi Laurence,

There is no built-in function to plot a segment of a circle. However, it is still possible to do with combinations of existing functions in MATLAB! Assuming that the center is defined as a point in Cartesian coordinates (X, Y, Z), you can add those values to the final x, y, z coordinates before plotting. Although it is easier to start with spherical coordinates, if you have Cartesian coordinates you can use the function cart2sph to convert them to spherical coordinates.

I was unsure if you wanted to plot a "slice" of the sphere that used the full range of the radius, the full range of phi, and the full range of theta, so I added the ability to select a smaller area to plot. Attached is my code to do so- hope this helps!

[Laurence hutton-smith]

Thank you for your help!

Answer 2

[Image Analyst]

You could adapt the FAQ: http://matlab.wikia.com/wiki/FAQ#How_do_I_create_an_arc.3F