Initial Commit

ViewportRestrictions/ProportionsRestriction.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Windows;
+
+namespace Microsoft.Research.DynamicDataDisplay.ViewportRestrictions
+{
+	public sealed class ProportionsRestriction : ViewportRestriction
+	{
+		private double widthToHeightRatio = 1;
+		public double WidthToHeightRatio
+		{
+			get { return widthToHeightRatio; }
+			set
+			{
+				if (widthToHeightRatio != value)
+				{
+					widthToHeightRatio = value;
+					RaiseChanged();
+				}
+			}
+		}
+
+		public override DataRect Apply(DataRect oldDataRect, DataRect newDataRect, Viewport2D viewport)
+		{
+			double ratio = newDataRect.Width / newDataRect.Height;
+			double coeff = Math.Sqrt(ratio);
+
+			double newWidth = newDataRect.Width / coeff;
+			double newHeight = newDataRect.Height * coeff;
+
+			Point center = newDataRect.GetCenter();
+			DataRect res = DataRect.FromCenterSize(center, newWidth, newHeight);
+			return res;
+		}
+	}
+}