Useful Sketch Arc Midpoint Function

function getArcMidpoint(center is Vector, start is Vector, end is Vector) returns Vector
{
    // need to convert 2D vectors back to 3D
    const center3D = vector(center[0], center[1], 0 * meter);
    const start3D = vector(start[0], start[1], 0 * meter);
    const end3D = vector(end[0], end[1], 0 * meter);

    const angle = angleBetween(center3D - start3D, center3D - end3D) / 2;
    start = center - start;

    var ca = cos(angle); // in radians
    var sa = sin(angle);

    return center - vector(ca * start[0] - sa * start[1], sa * start[0] + ca * start[1]);
}