OpenBve.CsvRwRouteParser.PreprocessSortByTrackPosition C# (CSharp) Method

		private static void PreprocessSortByTrackPosition(bool IsRW, double[] UnitFactors, ref Expression[] Expressions) {
			System.Globalization.CultureInfo Culture = System.Globalization.CultureInfo.InvariantCulture;
			PositionedExpression[] p = new PositionedExpression[Expressions.Length];
			int n = 0;
			double a = -1.0;
			bool NumberCheck = !IsRW;
			for (int i = 0; i < Expressions.Length; i++) {
				if (IsRW) {
					// only check for track positions in the railway section for RW routes
					if (Expressions[i].Text.StartsWith("[", StringComparison.Ordinal) & Expressions[i].Text.EndsWith("]", StringComparison.Ordinal)) {
						string s = Expressions[i].Text.Substring(1, Expressions[i].Text.Length - 2).Trim();
						if (string.Compare(s, "Railway", StringComparison.OrdinalIgnoreCase) == 0) {
							NumberCheck = true;
						} else {
							NumberCheck = false;
						}
					}
				}
				double x;
				if (NumberCheck && Interface.TryParseDouble(Expressions[i].Text, UnitFactors, out x)) {
					x += Expressions[i].TrackPositionOffset;
					if (x >= 0.0) {
						a = x;
					} else {
						Interface.AddMessage(Interface.MessageType.Error, false, "Negative track position encountered at line " + Expressions[i].Line.ToString(Culture) + ", column " + Expressions[i].Column.ToString(Culture) + " in file " + Expressions[i].File);
					}
				} else {
					p[n].TrackPosition = a;
					p[n].Expression = Expressions[i];
					int j = n;
					n++;
					while (j > 0) {
						if (p[j].TrackPosition < p[j - 1].TrackPosition) {
							PositionedExpression t = p[j];
							p[j] = p[j - 1];
							p[j - 1] = t;
							j--;
						} else {
							break;
						}
					}
				}
			}
			a = -1.0;
			Expression[] e = new Expression[Expressions.Length];
			int m = 0;
			for (int i = 0; i < n; i++) {
				if (p[i].TrackPosition != a) {
					a = p[i].TrackPosition;
					e[m] = new Expression();
					e[m].Text = (a / UnitFactors[UnitFactors.Length - 1]).ToString(Culture);
					e[m].Line = -1;
					e[m].Column = -1;
					m++;
				}
				e[m] = p[i].Expression;
				m++;
			}
			Array.Resize<Expression>(ref e, m);
			Expressions = e;
		}