From fc745bf827589e8755389baf3ea7f0b96ee7c300 Mon Sep 17 00:00:00 2001
From: James Jackson-South <james_south@hotmail.com>
Date: Fri, 21 Apr 2017 13:05:11 +1000
Subject: [PATCH 1/2] Add direct reference to System.IO.Compression

Classic Net461 apps require this even when referencing NetStandard1.6
when consuming a NetStandard library consuming ImageSharp.... Wut?!
---
 src/ImageSharp/ImageSharp.csproj | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/ImageSharp/ImageSharp.csproj b/src/ImageSharp/ImageSharp.csproj
index a19bed604..303e511d7 100644
--- a/src/ImageSharp/ImageSharp.csproj
+++ b/src/ImageSharp/ImageSharp.csproj
@@ -41,6 +41,7 @@
     <PackageReference Include="System.Threading.Tasks.Parallel" Version="4.3.0" />
     <PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="4.3.0" />
     <PackageReference Include="System.Numerics.Vectors" Version="4.3.0" />
+    <PackageReference Include="System.IO.Compression" Version="4.3.0" />
   </ItemGroup>
   <PropertyGroup>
     <CodeAnalysisRuleSet>..\..\ImageSharp.ruleset</CodeAnalysisRuleSet>

From 1012e57bc429ac67e05c2584b97f6cb7dd499dc4 Mon Sep 17 00:00:00 2001
From: James Jackson-South <james_south@hotmail.com>
Date: Fri, 21 Apr 2017 22:28:35 +1000
Subject: [PATCH 2/2] Move SinC to MathF [skip ci]

---
 src/ImageSharp/Common/Helpers/ImageMaths.cs   | 39 +------------------
 src/ImageSharp/Common/Helpers/MathF.cs        | 38 ++++++++++++++++++
 .../Resamplers/Lanczos2Resampler.cs           |  2 +-
 .../Resamplers/Lanczos3Resampler.cs           |  2 +-
 .../Resamplers/Lanczos5Resampler.cs           |  2 +-
 .../Resamplers/Lanczos8Resampler.cs           |  2 +-
 .../Transforms/Resamplers/WelchResampler.cs   |  2 +-
 7 files changed, 44 insertions(+), 43 deletions(-)

diff --git a/src/ImageSharp/Common/Helpers/ImageMaths.cs b/src/ImageSharp/Common/Helpers/ImageMaths.cs
index 224b267e4..1be7bd619 100644
--- a/src/ImageSharp/Common/Helpers/ImageMaths.cs
+++ b/src/ImageSharp/Common/Helpers/ImageMaths.cs
@@ -100,25 +100,6 @@ namespace ImageSharp
             return 0F;
         }
 
-        /// <summary>
-        /// Gets the result of a sine cardinal function for the given value.
-        /// </summary>
-        /// <param name="x">The value to calculate the result for.</param>
-        /// <returns>
-        /// The <see cref="float"/>.
-        /// </returns>
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static float SinC(float x)
-        {
-            if (MathF.Abs(x) > Constants.Epsilon)
-            {
-                x *= MathF.PI;
-                return Clean(MathF.Sin(x) / x);
-            }
-
-            return 1.0f;
-        }
-
         /// <summary>
         /// Returns the given degrees converted to radians.
         /// </summary>
@@ -286,23 +267,5 @@ namespace ImageSharp
 
             return GetBoundingRectangle(topLeft, bottomRight);
         }
-
-        /// <summary>
-        /// Ensures that any passed double is correctly rounded to zero
-        /// </summary>
-        /// <param name="x">The value to clean.</param>
-        /// <returns>
-        /// The <see cref="float"/>
-        /// </returns>.
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        private static float Clean(float x)
-        {
-            if (MathF.Abs(x) < Constants.Epsilon)
-            {
-                return 0F;
-            }
-
-            return x;
-        }
     }
-}
+}
\ No newline at end of file
diff --git a/src/ImageSharp/Common/Helpers/MathF.cs b/src/ImageSharp/Common/Helpers/MathF.cs
index 2ee700789..1877fe8af 100644
--- a/src/ImageSharp/Common/Helpers/MathF.cs
+++ b/src/ImageSharp/Common/Helpers/MathF.cs
@@ -126,6 +126,26 @@ namespace ImageSharp
             return (float)Math.Sin(f);
         }
 
+        /// <summary>
+        /// Returns the result of a normalized sine cardinal function for the given value.
+        /// SinC(x) = sin(pi*x)/(pi*x).
+        /// </summary>
+        /// <param name="f">A single-precision floating-point number to calculate the result for.</param>
+        /// <returns>
+        /// The sine cardinal of <paramref name="f" />.
+        /// </returns>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static float SinC(float f)
+        {
+            if (Abs(f) > Constants.Epsilon)
+            {
+                f *= PI;
+                return Clean(Sin(f) / f);
+            }
+
+            return 1F;
+        }
+
         /// <summary>Returns the square root of a specified number.</summary>
         /// <param name="f">The number whose square root is to be found. </param>
         /// <returns>
@@ -140,5 +160,23 @@ namespace ImageSharp
         {
             return (float)Math.Sqrt(f);
         }
+
+        /// <summary>
+        /// Ensures that any passed float is correctly rounded to zero
+        /// </summary>
+        /// <param name="x">The value to clean.</param>
+        /// <returns>
+        /// The <see cref="float"/>
+        /// </returns>.
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private static float Clean(float x)
+        {
+            if (Abs(x) < Constants.Epsilon)
+            {
+                return 0F;
+            }
+
+            return x;
+        }
     }
 }
\ No newline at end of file
diff --git a/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos2Resampler.cs b/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos2Resampler.cs
index 05d6c630f..a46f38df4 100644
--- a/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos2Resampler.cs
+++ b/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos2Resampler.cs
@@ -25,7 +25,7 @@ namespace ImageSharp.Processing
 
             if (x < 2F)
             {
-                return ImageMaths.SinC(x) * ImageMaths.SinC(x / 2F);
+                return MathF.SinC(x) * MathF.SinC(x / 2F);
             }
 
             return 0F;
diff --git a/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos3Resampler.cs b/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos3Resampler.cs
index 094e5bd67..3ad01b2b7 100644
--- a/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos3Resampler.cs
+++ b/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos3Resampler.cs
@@ -25,7 +25,7 @@ namespace ImageSharp.Processing
 
             if (x < 3F)
             {
-                return ImageMaths.SinC(x) * ImageMaths.SinC(x / 3F);
+                return MathF.SinC(x) * MathF.SinC(x / 3F);
             }
 
             return 0F;
diff --git a/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos5Resampler.cs b/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos5Resampler.cs
index 9022aaaaf..9bb8bdd16 100644
--- a/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos5Resampler.cs
+++ b/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos5Resampler.cs
@@ -25,7 +25,7 @@ namespace ImageSharp.Processing
 
             if (x < 5F)
             {
-                return ImageMaths.SinC(x) * ImageMaths.SinC(x / 5F);
+                return MathF.SinC(x) * MathF.SinC(x / 5F);
             }
 
             return 0F;
diff --git a/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos8Resampler.cs b/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos8Resampler.cs
index 4769d3847..af8c2c111 100644
--- a/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos8Resampler.cs
+++ b/src/ImageSharp/Processing/Transforms/Resamplers/Lanczos8Resampler.cs
@@ -25,7 +25,7 @@ namespace ImageSharp.Processing
 
             if (x < 8F)
             {
-                return ImageMaths.SinC(x) * ImageMaths.SinC(x / 8F);
+                return MathF.SinC(x) * MathF.SinC(x / 8F);
             }
 
             return 0F;
diff --git a/src/ImageSharp/Processing/Transforms/Resamplers/WelchResampler.cs b/src/ImageSharp/Processing/Transforms/Resamplers/WelchResampler.cs
index 6fafd8ebb..33a2cc825 100644
--- a/src/ImageSharp/Processing/Transforms/Resamplers/WelchResampler.cs
+++ b/src/ImageSharp/Processing/Transforms/Resamplers/WelchResampler.cs
@@ -24,7 +24,7 @@ namespace ImageSharp.Processing
 
             if (x < 3F)
             {
-                return ImageMaths.SinC(x) * (1F - (x * x / 9.0F));
+                return MathF.SinC(x) * (1F - (x * x / 9F));
             }
 
             return 0F;