Implemented frame proportions detection (one of the common aspect ratios)

Author: apdevelop

Src/ScreenGrid.Models/FlatImage.cs

@@ -91,7 +91,8 @@ private IList<IntegerSegment> FindVerticalZeroSegments(int ix, int minimalSegmen
 
         public Models.Geometry.Rectangle FindBoundsOfInnerImage()
         {
-            // TODO: add tests for this method
+            // TODO: implement more robust algorithm
+            // TODO: add more tests for this method
             const int minimalSegmentLength = 8;
 
             var stripeCH = IntegerSegmentUtils.FindZeroSegments(FlatImage.GetDerivative(this.GetHorizontalStripe(this.Height / 2)), minimalSegmentLength);

Src/ScreenGrid.ViewModels/ScreenGridViewModel.cs

@@ -283,23 +283,95 @@ private System.Windows.Shapes.Line CreateLine(double x1, double y1, double x2, d
             };
         }
 
-        public string CaptionText
+        private Tuple<int, int> ImageSize
         {
             get
             {
-                return String.Format(CultureInfo.InvariantCulture,
-                    "{0}\u00D7{1}",
+                return new Tuple<int, int>(
                     (int)(this.WindowWidth - 2 * OuterBorderWidth),
                     (int)(this.WindowHeight - 2 * OuterBorderWidth - HeaderHeight));
             }
         }
 
+        // TODO: move code to Models, add tests
+
+        /// <summary>
+        /// Common aspect ratios
+        /// https://en.wikipedia.org/wiki/Aspect_ratio_%28image%29
+        /// </summary>
+        private static Dictionary<double, string> CommonAspectRatios = new Dictionary<double, string>()
+        {
+            // TODO: create class with separated properties
+            // TODO: add descriptions for displaying in tooltip
+            { 1.0, "1:1" },
+            { 6.0 / 5.0, "6:5" },
+            { 5.0 / 4.0, "5:4" },
+            { 4.0 / 3.0, "4:3" },
+            { 11.0 / 8.0, "11:8" },
+            { Math.Sqrt(2.0), "1.41:1" }, // ISO 216 paper sizes
+            { 1.43, "1.43:1" },
+            { 3.0 / 2.0, "3:2" },
+            { 16.0 / 10.0, "16:10" }, // The golden ratio
+            { 1.618, "16.18:10" },
+            { 5.0 / 3.0, "5:3" },
+            { 16.0 / 9.0, "16:9" },
+            { 1.85, "1.85:1" },
+            { 2.35, "2.35:1" },
+            { 2.39, "2.39:1" },
+            { 2.414, "2.414:1" }, // The silver ratio
+            { 2.76, "2.76:1" },
+        };
+
+        private string AspectRatio
+        {
+            get
+            {
+                const double tolerance = 0.01;
+                var ratio = ((double)this.ImageSize.Item1) / ((double)this.ImageSize.Item2);
+
+                if (ratio >= 1.0)
+                {
+                    // Horizontal
+                    var nearest = CommonAspectRatios.OrderBy(kvp => Math.Abs(kvp.Key - ratio)).First();
+                    if (Math.Abs(nearest.Key - ratio) < tolerance)
+                    {
+                        return nearest.Value;
+                    }
+                }
+                else
+                {
+                    // Vertical
+                    ratio = 1.0 / ratio;
+                    var nearest = CommonAspectRatios.OrderBy(kvp => Math.Abs(kvp.Key - ratio)).First();
+                    if (Math.Abs(nearest.Key - ratio) < tolerance)
+                    {
+                        var arr = nearest.Value.Split(':');
+                        return String.Format(CultureInfo.InvariantCulture, "{0}:{1}", arr[1], arr[0]);
+                    }
+                }
+
+                return String.Empty;
+            }
+        }
+
+        public string CaptionText
+        {
+            get
+            {
+                return String.Format(CultureInfo.InvariantCulture,
+                    "{0}\u00D7{1}{2}",
+                    ImageSize.Item1,
+                    ImageSize.Item2,
+                    String.IsNullOrEmpty(this.AspectRatio) ? String.Empty : " (" + this.AspectRatio + ")");
+            }
+        }
+
         public void SnapToImageBounds()
         {
             // select foreground window from several processes of supported applications
             var nativeWindow = Models.AppsInterop.NativeWindow.GetTopMostWindow();
 
-            if (nativeWindow != null)
+            if (nativeWindow != null) // TODO: display error if no window was found
             {
                 if (nativeWindow.ClassName == Models.AppsInterop.PhotoViewerWindow.MainWindowClassName)
                 {

Src/ScreenGrid.Views/ScreenGridWindow.xaml.cs

@@ -9,17 +9,15 @@ public partial class ScreenGridWindow : Window
     {
         // TODO: Better separation of concerns (MVVM pattern)
 
-        // TODO: Target to browser window
-        // TODO: Frame proportions detection
         // TODO: Fix 'Golden Spiral' grid
-        // TODO: Snap to TotalCommander Lister window
         // TODO: Disable rotate/flip buttons depends on grid type
 
         // TODO: Find corners by colors change in uniform color
         // TODO: 'Auto-snap' option on/off
         // TODO: Move window by cursor keys
         // TODO: Remove image files from resources
-        // TODO: add grid color selection
+
+        // TODO: show checkboxes in menu items
 
         public ScreenGridWindow()
         {