Function rotate

rotate(
    triangle: Triangle,
    amountRadian?: number,
    origin?: Geometry.Point,
): Triangle
Returns a triangle that is rotated by angleRad. By default it rotates around its center but an arbitrary origin point can be provided.
```
let triangle = Triangles.fromPoints([a, b, c]);

// Rotate triangle by 5 degrees
triangle = Triangles.rotate(triangle, degreeToRadian(5));

// Rotate by 90 degrees
triangle = Triangles.rotate(triangle, Math.PI / 2);
```
Parameters
- triangle: Triangle
  Triangle to rotate
- OptionalamountRadian: number
  Angle in radians to rotate by
- Optionalorigin: Geometry.Point
  Point to rotate around. If undefined, middle of triangle will be used
Returns Triangle
A new triangle