Initial Commit

Charts/Isolines/IsolineTextAnnotater.cs

@@ -0,0 +1,74 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Collections.ObjectModel;
+using System.Windows;
+using Microsoft.Research.DynamicDataDisplay.Common;
+
+namespace Microsoft.Research.DynamicDataDisplay.Charts.Isolines
+{
+	/// <summary>
+	/// IsolineTextAnnotater defines methods to annotate isolines - create a list of labels with its position.
+	/// </summary>
+	public sealed class IsolineTextAnnotater
+	{
+		private double wayBeforeText = 10;
+		/// <summary>
+		/// Gets or sets the distance between text labels.
+		/// </summary>
+		public double WayBeforeText
+		{
+			get { return wayBeforeText; }
+			set { wayBeforeText = value; }
+		}
+
+		/// <summary>
+		/// Annotates the specified isoline collection.
+		/// </summary>
+		/// <param name="collection">The collection.</param>
+		/// <param name="visible">The visible rectangle.</param>
+		/// <returns></returns>
+		public Collection<IsolineTextLabel> Annotate(IsolineCollection collection, DataRect visible)
+		{
+			Collection<IsolineTextLabel> res = new Collection<IsolineTextLabel>();
+
+			foreach (var line in collection.Lines)
+			{
+				double way = 0;
+
+				var forwardSegments = line.GetSegments();
+				var forwardEnumerator = forwardSegments.GetEnumerator();
+				forwardEnumerator.MoveNext();
+
+				foreach (var segment in line.GetSegments())
+				{
+					bool hasForwardSegment = forwardEnumerator.MoveNext();
+
+					double length = segment.GetLength();
+					way += length;
+					if (way > wayBeforeText)
+					{
+						way = 0;
+
+						var rotation = (segment.Max - segment.Min).ToAngle();
+						if (hasForwardSegment)
+						{
+							var forwardSegment = forwardEnumerator.Current;
+							rotation = (rotation + (forwardSegment.Max - forwardSegment.Min).ToAngle()) / 2;
+						}
+
+						res.Add(new IsolineTextLabel
+						{
+							Value = line.RealValue,
+							Position = segment.Max,
+							Rotation = rotation
+						});
+					}
+				}
+			}
+
+			return res;
+		}
+	}
+}