private IVector2[] GetCircleCenters(IVector2 p1, IVector2 p2, double radius)
{
try
{
if (radius < 0)
{
throw new ArgumentException("Negative radius.");
}
if (radius == 0)
{
if (p1 == p2)
{
return new[] { p1 }
}
;
else
{
throw new InvalidOperationException("No circles.");
}
}
if (p1 == p2)
{
throw new InvalidOperationException("Infinite number of circles.");
}
double sqDistance = Math.Pow(p1.DistanceTo(p2), 2);
double sqDiameter = 4 * radius * radius;
if (sqDistance > sqDiameter)
{
throw new InvalidOperationException("Points are too far apart.");
}
var midPoint = new Vector2((p1.X + p2.X) / 2, (p1.Y + p2.Y) / 2);
if (sqDistance == sqDiameter)
{
return new[] { midPoint }
}
;
double d = Math.Sqrt(radius * radius - sqDistance / 4);
double distance = Math.Sqrt(sqDistance);
double ox = d * (p2.X - p1.X) / distance, oy = d * (p2.Y - p1.Y) / distance;
return(new[] {
new Vector2(midPoint.X - oy, midPoint.Y + ox),
new Vector2(midPoint.X + oy, midPoint.Y - ox)
});
}
catch (Exception)
{
throw;
}
}
