Switches to rectangle structure for the rotation calculations

Former-commit-id: cc6abe13bd9824d32250738b25486cc5c9195849
Former-commit-id: 5bfec4b1d233e2390c92a5e565e537a84c380c8c

src/ImageProcessor.UnitTests/ImageProcessor.UnitTests.csproj

@@ -64,7 +64,7 @@
     <Compile Include="Imaging\ColorUnitTests.cs" />
     <Compile Include="Imaging\CropLayerUnitTests.cs" />
     <Compile Include="Imaging\FastBitmapUnitTests.cs" />
-    <Compile Include="Imaging\RotationUnitTests.cs" />
+    <Compile Include="Imaging\Helpers\ImageMathsUnitTests.cs" />
   </ItemGroup>
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
   <ItemGroup>

src/ImageProcessor.UnitTests/Imaging/Helpers/ImageMathsUnitTests.cs

@@ -5,20 +5,38 @@
     using ImageProcessor.Imaging.Helpers;
     using NUnit.Framework;
 
+    /// <summary>
+    /// Test harness for the image math unit tests
+    /// </summary>
     public class ImageMathsUnitTests
     {
+        /// <summary>
+        /// Tests that the bounding rectangle of a rotated image is calculated
+        /// </summary>
+        /// <param name="width">The width of the image.</param>
+        /// <param name="height">The height of the image.</param>
+        /// <param name="angle">The rotation angle.</param>
+        /// <param name="expectedWidth">The expected width.</param>
+        /// <param name="expectedHeight">The expected height.</param>
         [Test]
         [TestCase(100, 100, 45, 141, 141)]
         [TestCase(100, 100, 30, 137, 137)]
         [TestCase(100, 200, 50, 217, 205)]
-        public void NewSizeAfterRotationIsCalculated(int width, int height, float angle, int expectedWidth, int expectedHeight)
+        public void BoundingRotatedRectangleIsCalculated(int width, int height, float angle, int expectedWidth, int expectedHeight)
         {
-            Size result = ImageMaths.GetBoundingRotatedRectangle(width, height, angle);
+            Rectangle result = ImageMaths.GetBoundingRotatedRectangle(width, height, angle);
 
             result.Width.Should().Be(expectedWidth, "because the rotated width should have been calculated");
             result.Height.Should().Be(expectedHeight, "because the rotated height should have been calculated");
         }
 
+        /// <summary>
+        /// Tests that the zoom needed for an "inside" rotation is calculated
+        /// </summary>
+        /// <param name="imageWidth">Width of the image.</param>
+        /// <param name="imageHeight">Height of the image.</param>
+        /// <param name="angle">The rotation angle.</param>
+        /// <param name="expected">The expected zoom.</param>
         [Test]
         [TestCase(100, 100, 45, 1.41f)]
         [TestCase(100, 100, 15, 1.22f)]

src/ImageProcessor/ImageProcessor.csproj

@@ -215,7 +215,6 @@
     <Compile Include="Imaging\ResizeMode.cs" />
     <Compile Include="Imaging\Resizer.cs" />
     <Compile Include="Imaging\RotateInsideLayer.cs" />
-    <Compile Include="Imaging\Rotation.cs" />
     <Compile Include="Imaging\RoundedCornerLayer.cs" />
     <Compile Include="Imaging\TextLayer.cs" />
     <Compile Include="Processors\Alpha.cs" />

src/ImageProcessor/Imaging/Helpers/ImageMaths.cs

@@ -111,7 +111,7 @@ namespace ImageProcessor.Imaging.Helpers
         /// <param name="height">The height of the image.</param>
         /// <param name="angle">The angle of rotation.</param>
         /// <returns>The new size of the image</returns>
-        public static Size GetBoundingRotatedRectangle(int width, int height, float angle)
+        public static Rectangle GetBoundingRotatedRectangle(int width, int height, float angle)
         {
             double widthAsDouble = width;
             double heightAsDouble = height;
@@ -129,9 +129,11 @@ namespace ImageProcessor.Imaging.Helpers
             double height2 = (widthAsDouble * radiansSin) + (heightAsDouble * radiansCos);
 
             // Get the external vertex for the rotation
-            Size result = new Size();
-            result.Width = Convert.ToInt32(Math.Max(Math.Abs(width1), Math.Abs(width2)));
-            result.Height = Convert.ToInt32(Math.Max(Math.Abs(height1), Math.Abs(height2)));
+            Rectangle result = new Rectangle(
+                0,
+                0,
+                Convert.ToInt32(Math.Max(Math.Abs(width1), Math.Abs(width2))),
+                Convert.ToInt32(Math.Max(Math.Abs(height1), Math.Abs(height2))));
 
             return result;
         }

src/ImageProcessor/Processors/Rotate.cs

@@ -104,7 +104,7 @@ namespace ImageProcessor.Processors
         /// </remarks>
         private Bitmap RotateImage(Image image, float rotateAtX, float rotateAtY, float angle)
         {
-            Size newSize = Imaging.Helpers.ImageMaths.GetBoundingRotatedRectangle(image.Width, image.Height, angle);
+            Rectangle newSize = Imaging.Helpers.ImageMaths.GetBoundingRotatedRectangle(image.Width, image.Height, angle);
 
             int x = (newSize.Width - image.Width) / 2;
             int y = (newSize.Height - image.Height) / 2;