Add Abgr32 pixel type, extend IPixel<T>

src/ImageSharp/Advanced/AotCompilerTools.cs

@@ -75,6 +75,7 @@ private static void SeedPixelFormats()
 
                 Seed<A8>();
                 Seed<Argb32>();
+                Seed<Abgr32>();
                 Seed<Bgr24>();
                 Seed<Bgr565>();
                 Seed<Bgra32>();
@@ -149,6 +150,7 @@ private static unsafe void AotCompileImage<TPixel>()
             Image<TPixel> img = default;
             img.CloneAs<A8>(default);
             img.CloneAs<Argb32>(default);
+            img.CloneAs<Abgr32>(default);
             img.CloneAs<Bgr24>(default);
             img.CloneAs<Bgr565>(default);
             img.CloneAs<Bgra32>(default);

src/ImageSharp/Color/Color.Conversions.cs

@@ -89,6 +89,17 @@ public Color(Bgra32 pixel)
             this.boxedHighPrecisionPixel = null;
         }
 
+        /// <summary>
+        /// Initializes a new instance of the <see cref="Color"/> struct.
+        /// </summary>
+        /// <param name="pixel">The <see cref="Abgr32"/> containing the color information.</param>
+        [MethodImpl(InliningOptions.ShortMethod)]
+        public Color(Abgr32 pixel)
+        {
+            this.data = new Rgba64(pixel);
+            this.boxedHighPrecisionPixel = null;
+        }
+
         /// <summary>
         /// Initializes a new instance of the <see cref="Color"/> struct.
         /// </summary>
@@ -177,6 +188,19 @@ internal Argb32 ToArgb32()
             return value;
         }
 
+        [MethodImpl(InliningOptions.ShortMethod)]
+        internal Abgr32 ToAbgr32()
+        {
+            if (this.boxedHighPrecisionPixel is null)
+            {
+                return this.data.ToAbgr32();
+            }
+
+            Abgr32 value = default;
+            value.FromScaledVector4(this.boxedHighPrecisionPixel.ToScaledVector4());
+            return value;
+        }
+
         [MethodImpl(InliningOptions.ShortMethod)]
         internal Rgb24 ToRgb24()
         {

src/ImageSharp/Common/Helpers/Numerics.cs

@@ -907,5 +907,61 @@ ref MemoryMarshal.GetReference(Log2DeBruijn),
         /// <param name="divisor">Divisor value.</param>
         /// <returns>Ceiled division result.</returns>
         public static uint DivideCeil(uint value, uint divisor) => (value + divisor - 1) / divisor;
+
+        /// <summary>
+        /// Rotates the specified value left by the specified number of bits.
+        /// </summary>
+        /// <param name="value">The value to rotate.</param>
+        /// <param name="offset">The number of bits to rotate with.</param>
+        /// <returns>The rotated value.</returns>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static uint RotateLeft(uint value, int offset)
+        {
+#if SUPPORTS_BITOPERATIONS
+            return BitOperations.RotateLeft(value, offset);
+#else
+            return RotateLeftSoftwareFallback(value, offset);
+#endif
+        }
+
+#if !SUPPORTS_BITOPERATIONS
+        /// <summary>
+        /// Rotates the specified value left by the specified number of bits.
+        /// </summary>
+        /// <param name="value">The value to rotate.</param>
+        /// <param name="offset">The number of bits to rotate with.</param>
+        /// <returns>The rotated value.</returns>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static uint RotateLeftSoftwareFallback(uint value, int offset)
+            => (value << offset) | (value >> (32 - offset));
+#endif
+
+        /// <summary>
+        /// Rotates the specified value right by the specified number of bits.
+        /// </summary>
+        /// <param name="value">The value to rotate.</param>
+        /// <param name="offset">The number of bits to rotate with.</param>
+        /// <returns>The rotated value.</returns>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static uint RotateRight(uint value, int offset)
+        {
+#if SUPPORTS_BITOPERATIONS
+            return BitOperations.RotateRight(value, offset);
+#else
+            return RotateRightSoftwareFallback(value, offset);
+#endif
+        }
+
+#if !SUPPORTS_BITOPERATIONS
+        /// <summary>
+        /// Rotates the specified value right by the specified number of bits.
+        /// </summary>
+        /// <param name="value">The value to rotate.</param>
+        /// <param name="offset">The number of bits to rotate with.</param>
+        /// <returns>The rotated value.</returns>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static uint RotateRightSoftwareFallback(uint value, int offset)
+            => (value >> offset) | (value << (32 - offset));
+#endif
     }
 }

src/ImageSharp/Common/Helpers/Shuffle/IComponentShuffle.cs

@@ -157,7 +157,7 @@ public void RunFallbackShuffle(ReadOnlySpan<byte> source, Span<byte> dest)
 
                 // packed              = [W Z Y X]
                 // ROTR(8, packedArgb) = [Y Z W X]
-                Unsafe.Add(ref dBase, i) = (packed >> 8) | (packed << 24);
+                Unsafe.Add(ref dBase, i) = Numerics.RotateRight(packed, 8);
             }
         }
     }
@@ -188,7 +188,40 @@ public void RunFallbackShuffle(ReadOnlySpan<byte> source, Span<byte> dest)
                 // tmp1 + tmp3         = [W X Y Z]
                 uint tmp1 = packed & 0xFF00FF00;
                 uint tmp2 = packed & 0x00FF00FF;
-                uint tmp3 = (tmp2 << 16) | (tmp2 >> 16);
+                uint tmp3 = Numerics.RotateLeft(tmp2, 16);
+
+                Unsafe.Add(ref dBase, i) = tmp1 + tmp3;
+            }
+        }
+    }
+
+    internal readonly struct XWZYShuffle4 : IShuffle4
+    {
+        public byte Control
+        {
+            [MethodImpl(InliningOptions.ShortMethod)]
+            get => SimdUtils.Shuffle.MmShuffle(1, 2, 3, 0);
+        }
+
+        [MethodImpl(InliningOptions.ShortMethod)]
+        public void RunFallbackShuffle(ReadOnlySpan<byte> source, Span<byte> dest)
+        {
+            ref uint sBase = ref Unsafe.As<byte, uint>(ref MemoryMarshal.GetReference(source));
+            ref uint dBase = ref Unsafe.As<byte, uint>(ref MemoryMarshal.GetReference(dest));
+            int n = source.Length / 4;
+
+            for (int i = 0; i < n; i++)
+            {
+                uint packed = Unsafe.Add(ref sBase, i);
+
+                // packed              = [W Z Y X]
+                // tmp1                = [0 Z 0 X]
+                // tmp2                = [W 0 Y 0]
+                // tmp3=ROTL(16, tmp2) = [Y 0 W 0]
+                // tmp1 + tmp3         = [Y Z W X]
+                uint tmp1 = packed & 0x00FF00FF;
+                uint tmp2 = packed & 0xFF00FF00;
+                uint tmp3 = Numerics.RotateLeft(tmp2, 16);
 
                 Unsafe.Add(ref dBase, i) = tmp1 + tmp3;
             }

src/ImageSharp/ImageSharp.csproj

@@ -75,6 +75,11 @@
       <AutoGen>True</AutoGen>
       <DependentUpon>Block8x8F.Generated.tt</DependentUpon>
     </Compile>
+    <Compile Update="PixelFormats\PixelImplementations\PixelOperations\Generated\Abgr32.PixelOperations.Generated.cs">
+      <DesignTime>True</DesignTime>
+      <AutoGen>True</AutoGen>
+      <DependentUpon>Abgr32.PixelOperations.Generated.tt</DependentUpon>
+    </Compile>
     <Compile Update="PixelFormats\PixelOperations{TPixel}.Generated.cs">
       <DesignTime>True</DesignTime>
       <AutoGen>True</AutoGen>
@@ -166,6 +171,10 @@
       <Generator>TextTemplatingFileGenerator</Generator>
       <LastGenOutput>Block8x8F.Generated.cs</LastGenOutput>
     </None>
+    <None Update="PixelFormats\PixelImplementations\PixelOperations\Generated\Abgr32.PixelOperations.Generated.tt">
+      <Generator>TextTemplatingFileGenerator</Generator>
+      <LastGenOutput>Abgr32.PixelOperations.Generated.cs</LastGenOutput>
+    </None>
     <None Update="PixelFormats\PixelOperations{TPixel}.Generated.tt">
       <Generator>TextTemplatingFileGenerator</Generator>
       <LastGenOutput>PixelOperations{TPixel}.Generated.cs</LastGenOutput>

src/ImageSharp/PixelFormats/IPixel.cs

@@ -79,6 +79,12 @@ public interface IPixel
         /// <param name="source">The <see cref="Bgra32"/> value.</param>
         void FromBgra32(Bgra32 source);
 
+        /// <summary>
+        /// Initializes the pixel instance from an <see cref="Abgr32"/> value.
+        /// </summary>
+        /// <param name="source">The <see cref="Abgr32"/> value.</param>
+        void FromAbgr32(Abgr32 source);
+
         /// <summary>
         /// Initializes the pixel instance from an <see cref="L8"/> value.
         /// </summary>

src/ImageSharp/PixelFormats/PixelImplementations/A8.cs

@@ -87,6 +87,10 @@ public partial struct A8 : IPixel<A8>, IPackedVector<byte>
         [MethodImpl(InliningOptions.ShortMethod)]
         public void FromBgra32(Bgra32 source) => this.PackedValue = source.A;
 
+        /// <inheritdoc/>
+        [MethodImpl(InliningOptions.ShortMethod)]
+        public void FromAbgr32(Abgr32 source) => this.PackedValue = source.A;
+
         /// <inheritdoc/>
         [MethodImpl(InliningOptions.ShortMethod)]
         public void FromBgra5551(Bgra5551 source) => this.FromScaledVector4(source.ToScaledVector4());