Initial Commit

Transforms/CoordinateTransform.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Windows;
+using Microsoft.Research.DynamicDataDisplay.Common;
+using System.Diagnostics;
+using System.Windows.Media;
+
+namespace Microsoft.Research.DynamicDataDisplay
+{
+    /// <summary>
+    /// A central class in 2d coordinate transformation in DynamicDataDisplay.
+    /// Provides methods to transform point from one coordinate system to another.
+    /// Should be immutable.
+    /// </summary>
+    public sealed class CoordinateTransform
+    {
+        private CoordinateTransform(DataRect visibleRect, Rect screenRect)
+        {
+            this.visibleRect = visibleRect;
+            this.screenRect = screenRect;
+
+            rxToScreen = screenRect.Width / visibleRect.Width;
+            ryToScreen = screenRect.Height / visibleRect.Height;
+            cxToScreen = visibleRect.XMin * rxToScreen - screenRect.Left;
+            cyToScreen = screenRect.Height + screenRect.Top + visibleRect.YMin * ryToScreen;
+
+            rxToData = visibleRect.Width / screenRect.Width;
+            ryToData = visibleRect.Height / screenRect.Height;
+            cxToData = screenRect.Left * rxToData - visibleRect.XMin;
+            cyToData = visibleRect.Height + visibleRect.YMin + screenRect.Top * ryToData;
+        }
+
+        #region Coeffs
+        double rxToScreen;
+        double ryToScreen;
+        double cxToScreen;
+        double cyToScreen;
+
+        double rxToData;
+        double ryToData;
+        double cxToData;
+        double cyToData;
+        #endregion
+
+        #region Creation methods
+
+        internal static CoordinateTransform FromRects(DataRect visibleRect, Rect screenRect)
+        {
+            CoordinateTransform result = new CoordinateTransform(visibleRect, screenRect);
+            return result;
+        }
+
+        internal CoordinateTransform WithRects(DataRect visibleRect, Rect screenRect)
+        {
+            CoordinateTransform copy = new CoordinateTransform(visibleRect, screenRect);
+            copy.dataTransform = dataTransform;
+            return copy;
+        }
+
+        /// <summary>
+        /// Creates a new instance of CoordinateTransform with the given data transform.
+        /// </summary>
+        /// <param name="dataTransform">The data transform.</param>
+        /// <returns></returns>
+        public CoordinateTransform WithDataTransform(DataTransform dataTransform)
+        {
+            if (dataTransform == null)
+                throw new ArgumentNullException("dataTransform");
+
+            CoordinateTransform copy = new CoordinateTransform(visibleRect, screenRect);
+            copy.dataTransform = dataTransform;
+            return copy;
+        }
+
+        internal CoordinateTransform WithScreenOffset(double x, double y)
+        {
+            Rect screenCopy = screenRect;
+            screenCopy.Offset(x, y);
+            CoordinateTransform copy = new CoordinateTransform(visibleRect, screenCopy);
+            return copy;
+        }
+
+        internal static CoordinateTransform CreateDefault()
+        {
+            CoordinateTransform transform = new CoordinateTransform(new Rect(0, 0, 1, 1), new Rect(0, 0, 1, 1));
+
+            return transform;
+        }
+
+        #endregion
+
+        #region Transform methods
+
+        /// <summary>
+        /// Transforms point from data coordinates to screen.
+        /// </summary>
+        /// <param name="dataPoint">The point in data coordinates.</param>
+        /// <returns></returns>
+        public Point DataToScreen(Point dataPoint)
+        {
+            Point viewportPoint = dataTransform.DataToViewport(dataPoint);
+
+            Point screenPoint = new Point(viewportPoint.X * rxToScreen - cxToScreen,
+                cyToScreen - viewportPoint.Y * ryToScreen);
+
+            return screenPoint;
+        }
+
+        /// <summary>
+        /// Transforms point from screen coordinates to data coordinates.
+        /// </summary>
+        /// <param name="screenPoint">The point in screen coordinates.</param>
+        /// <returns></returns>
+        public Point ScreenToData(Point screenPoint)
+        {
+            Point viewportPoint = new Point(screenPoint.X * rxToData - cxToData,
+                cyToData - screenPoint.Y * ryToData);
+
+            Point dataPoint = dataTransform.ViewportToData(viewportPoint);
+
+            return dataPoint;
+        }
+
+        /// <summary>
+        /// Transforms point from viewport coordinates to screen coordinates.
+        /// </summary>
+        /// <param name="viewportPoint">The point in viewport coordinates.</param>
+        /// <returns></returns>
+        public Point ViewportToScreen(Point viewportPoint)
+        {
+            Point screenPoint = new Point(viewportPoint.X * rxToScreen - cxToScreen,
+                cyToScreen - viewportPoint.Y * ryToScreen);
+
+            return screenPoint;
+        }
+
+        /// <summary>
+        /// Transforms point from screen coordinates to viewport coordinates.
+        /// </summary>
+        /// <param name="screenPoint">The point in screen coordinates.</param>
+        /// <returns></returns>
+        public Point ScreenToViewport(Point screenPoint)
+        {
+            Point viewportPoint = new Point(screenPoint.X * rxToData - cxToData,
+                cyToData - screenPoint.Y * ryToData);
+
+            return viewportPoint;
+        }
+
+        #endregion
+
+        [DebuggerBrowsable(DebuggerBrowsableState.Never)]
+        private DataRect visibleRect;
+        /// <summary>
+        /// Gets the viewport rectangle.
+        /// </summary>
+        /// <value>The viewport rect.</value>
+        public DataRect ViewportRect
+        {
+            get { return visibleRect; }
+        }
+
+        [DebuggerBrowsable(DebuggerBrowsableState.Never)]
+        private Rect screenRect;
+        /// <summary>
+        /// Gets the screen rectangle.
+        /// </summary>
+        /// <value>The screen rect.</value>
+        public Rect ScreenRect
+        {
+            get { return screenRect; }
+        }
+
+        [DebuggerBrowsable(DebuggerBrowsableState.Never)]
+        private DataTransform dataTransform = DataTransforms.Identity;
+        /// <summary>
+        /// Gets the data transform.
+        /// </summary>
+        /// <value>The data transform.</value>
+        public DataTransform DataTransform
+        {
+            get { return dataTransform; }
+        }
+    }
+}