Vertex.cs

// -----------------------------------------------------------------------
// <copyright file="Vertex.cs" company="">
// Triangle.NET Copyright (c) 2012-2022 Christian Woltering
// </copyright>
// -----------------------------------------------------------------------

namespace TriangleNet.Geometry
{
    using System;
    using TriangleNet.Topology;

    /// <summary>
    /// The vertex data structure.
    /// </summary>
    public class Vertex : Point
    {
        // Hash for dictionary. Will be set by mesh instance.
        internal int hash;

#if USE_ATTRIBS
        internal double[] attributes;
#endif
        internal VertexType type;
        internal Otri tri;

        /// <summary>
        /// Initializes a new instance of the <see cref="Vertex" /> class.
        /// </summary>
        public Vertex()
            : this(0, 0, 0)
        {
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="Vertex" /> class.
        /// </summary>
        /// <param name="x">The x coordinate of the vertex.</param>
        /// <param name="y">The y coordinate of the vertex.</param>
        public Vertex(double x, double y)
            : this(x, y, 0)
        {
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="Vertex" /> class.
        /// </summary>
        /// <param name="x">The x coordinate of the vertex.</param>
        /// <param name="y">The y coordinate of the vertex.</param>
        /// <param name="mark">The boundary mark.</param>
        public Vertex(double x, double y, int mark)
            : base(x, y, mark)
        {
            type = VertexType.InputVertex;
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="Vertex" /> class.
        /// </summary>
        /// <param name="x">The x coordinate of the vertex.</param>
        /// <param name="y">The y coordinate of the vertex.</param>
        /// <param name="mark">The boundary mark.</param>
        /// <param name="type">The vertex type.</param>
        public Vertex(double x, double y, int mark, VertexType type)
            : base(x, y, mark)
        {
            this.type = type;
        }

#if USE_ATTRIBS
        /// <summary>
        /// Initializes a new instance of the <see cref="Vertex" /> class.
        /// </summary>
        /// <param name="x">The x coordinate of the vertex.</param>
        /// <param name="y">The y coordinate of the vertex.</param>
        /// <param name="mark">The boundary mark.</param>
        /// <param name="attribs">The number of point attributes.</param>
        public Vertex(double x, double y, int mark, int attribs)
            : this(x, y, mark)
        {
            if (attribs > 0)
            {
                this.attributes = new double[attribs];
            }
        }
#endif

        #region Public properties

#if USE_ATTRIBS
        /// <summary>
        /// Gets the vertex attributes (may be null).
        /// </summary>
        public double[] Attributes
        {
            get { return this.attributes; }
        }
#endif

        /// <summary>
        /// Gets the vertex type.
        /// </summary>
        public VertexType Type => type;

        /// <summary>
        /// Gets the specified coordinate of the vertex.
        /// </summary>
        /// <param name="i">Coordinate index.</param>
        /// <returns>X coordinate, if index is 0, Y coordinate, if index is 1.</returns>
        public double this[int i]
        {
            get
            {
                if (i == 0) return x;
                if (i == 1) return y;

                throw new ArgumentOutOfRangeException("Index must be 0 or 1.");
            }
        }

        #endregion

        /// <inheritdoc />
        public override int GetHashCode() => hash;
    }
}