HandyControl/Net40/HandyControl_Net40/Tools/Extension/GeometryExtension.cs

using System;
using System.Windows;
using System.Windows.Media;
using HandyControl.Expression.Drawing;

namespace HandyControl.Tools.Extension
{
    public static class GeometryExtension
    {
        /// <summary>
        ///     获取路径总长度
        /// </summary>
        /// <param name="geometry"></param>
        /// <returns></returns>
        public static double GetTotalLength(this Geometry geometry)
        {
            if (geometry == null) return 0;

            var pathGeometry = PathGeometry.CreateFromGeometry(geometry);
            pathGeometry.GetPointAtFractionLength(1e-4, out var point, out _);
            var length = (pathGeometry.Figures[0].StartPoint - point).Length * 1e+4;

            return length;
        }

        /// <summary>
        ///     获取路径总长度
        /// </summary>
        /// <param name="geometry"></param>
        /// <param name="size"></param>
        /// <param name="strokeThickness"></param>
        /// <returns></returns>
        public static double GetTotalLength(this Geometry geometry, Size size, double strokeThickness = 1)
        {
            if (geometry == null) return 0;

            if (MathHelper.IsVerySmall(size.Width) || MathHelper.IsVerySmall(size.Height)) return 0;

            var length = GetTotalLength(geometry);
            var sw = geometry.Bounds.Width / size.Width;
            var sh = geometry.Bounds.Height / size.Height;
            var min = Math.Min(sw, sh);

            if (MathHelper.IsVerySmall(min) || MathHelper.IsVerySmall(strokeThickness)) return 0;

            length /= min;
            return length / strokeThickness;
        }
    }
}