Finding the coordinates on the edge of a circle [c

问题:

Closed. This question is off-topic. It is not currently accepting answers.

---

Want to improve this question? Update the question so it's on-topic for Stack Overflow.

Closed 2 years ago.

Using C#:

How do I get the (x, y) coordinates on the edge of a circle for any given degree, if I have the center coordinates and the radius?

There is probably SIN, TAN, COSIN and other grade ten math involved... :)

回答1:

This has nothing to do with C#. There is just some elementary mathematics involved.

x = x0 + r * cos(theta)
y = y0 + r * sin(theta)

theta is in radians, x0 and y0 are the coordinates of the centre, r is the radius, and the angle is measured anticlockwise from the x-axis. But if you want it in C#, and your angle is in degrees:

double x = x0 + r * Math.Cos(theta * Math.PI / 180);
double y = y0 + r * Math.Sin(theta * Math.PI / 180);

回答2:

using Pythagoras Theorem (where x1,y1 is the edge point):

x1 = x + rcos(theta)
y1 = y + rsin(theta)

in C#, this would look like:

x1 = x + radius * Math.Cos(angle * (Math.PI / 180));
y1 = y + radius * Math.Sin(angle * (Math.PI / 180));

where all variables are doubles and angle is in degrees

回答3:

For a circle with origin (j, k), radius r, and angle t in radians:

   x(t) = r * cos(t) + j       
   y(t) = r * sin(t) + k