Function fromRadius

fromRadius(
    origin: Geometry.Point,
    radius: number,
    opts?: { initialAngleRadian?: number },
): Triangle
Returns an equilateral triangle centered at the origin.
```
// Create a triangle at 100,100 with radius of 60
const tri = fromRadius({x:100,y:100}, 60);

// Triangle with point A upwards, B to the right, C to the left
constr tri2 = fromRadius({x:100,y:100}, 60, {initialAngleRadian: -Math.PI / 2});
```
Parameters
- origin: Geometry.Point
  Origin
- radius: number
  Radius of triangle
- opts: { initialAngleRadian?: number } = {}
  Options
Returns Triangle