/// <summary>
/// Checks if vertices meet the logical requirements, if not throws exception.
/// Logical requirements:
/// 1. The Vertices are unique. (no duplicates)
/// 2. Distances between any two pair of consecutive vertices are equal.
/// 3. Center of the vertices (center of the circumsribed circle) is equidistant to all vertices
/// </summary>
/// <param name="vertices">Array of consecutive vertices</param>
public void ValidateVertices(Vertex[] vertices)
{
if (vertices == null)
{
throw new RegularPolygonLogicalException("Regular polygon can not be created without providing vertices.");
}
if (vertices.Length < 3)
{
throw new RegularPolygonLogicalException($"Regular polygon has at least 3 vertices ({vertices.Length} < 3).");
}
//checks vertices for uniqueness (no duplicates)
foreach (Vertex vertex in vertices)
{
if (vertices.Count(v => v.X.Equals(vertex.X) && v.Y.Equals(vertex.X)) > 1)
{
throw new RegularPolygonLogicalException("Regular polygon can not consists of duplicate vertices.");
}
}
//check vertices for side length equality
double sideLength = vertices[0].CalculateLength(vertices[vertices.Length - 1]);
for (int i = 0; i < vertices.Length - 1; i++)
{
if (!Utility.CompareDouble(vertices[i].CalculateLength(vertices[i + 1]), sideLength))
{
throw new RegularPolygonLogicalException("Regular polygon must have all sides the same length.");
}
}
//checks if the center of vertices (center of circumsribed circle) is equidistant to all vertices
double avgX = vertices.Average(v => v.X);
double avgY = vertices.Average(v => v.Y);
Vertex circleCenter = new Vertex(avgX, avgY);
double circleRadius = vertices[0].CalculateLength(circleCenter);
for (int i = 1; i < vertices.Length; i++)
{
if (!Utility.CompareDouble(vertices[i].CalculateLength(circleCenter), circleRadius))
{
throw new RegularPolygonLogicalException(
"The circle must be circumscribed on the regular polygon.");
}
}
}
/// <summary>
/// Indicates whether the current object is equal to another object of the same type. Uses PolygonLibraryUtility.
/// </summary>
/// <param name="other">An object to compare with this object.</param>
/// <see cref="PolygonLibrary.PolygonLibraryUtility.CompareDouble"/>
/// <returns>
/// <see langword="true" /> if the current object is equal to the <paramref name="other" /> parameter; otherwise, <see langword="false" />.
/// </returns>
public bool Equals(Vertex other)
{
return(Utility.CompareDouble(X, other.X) && Utility.CompareDouble(Y, other.Y));
}
