make .FromVector4() destructive

ImageSharp.sln.DotSettings

@@ -382,6 +382,7 @@
 	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ECSharpKeepExistingMigration/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ECSharpPlaceEmbeddedOnSameLineMigration/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ECSharpRenamePlacementToArrangementMigration/@EntryIndexedValue">True</s:Boolean>
+	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ECSharpUseContinuousIndentInsideBracesMigration/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ESettingsUpgrade_002EAddAccessorOwnerDeclarationBracesMigration/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ESettingsUpgrade_002EAlwaysTreatStructAsNotReorderableMigration/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ESettingsUpgrade_002ECSharpPlaceAttributeOnSameLineMigration/@EntryIndexedValue">True</s:Boolean>

src/ImageSharp/Common/Helpers/Guard.cs

@@ -257,6 +257,26 @@ namespace SixLabors.ImageSharp
             }
         }
 
+        /// <summary>
+        /// Verifies that the 'destination' span is not shorter than 'source'.
+        /// </summary>
+        /// <typeparam name="TSource">The source element type</typeparam>
+        /// <typeparam name="TDest">The destination element type</typeparam>
+        /// <param name="source">The source span</param>
+        /// <param name="destination">The destination span</param>
+        /// <param name="destinationParamName">The name of the argument for 'destination'</param>
+        [MethodImpl(InliningOptions.ShortMethod)]
+        public static void DestinationShouldNotBeTooShort<TSource, TDest>(
+            Span<TSource> source,
+            Span<TDest> destination,
+            string destinationParamName)
+        {
+            if (destination.Length < source.Length)
+            {
+                ThrowArgumentException($"Destination span is too short!", destinationParamName);
+            }
+        }
+
         /// <summary>
         /// Verifies, that the `source` span has the length of 'minLength', or longer.
         /// </summary>

src/ImageSharp/PixelFormats/PixelImplementations/Generated/Argb32.PixelOperations.Generated.cs

@@ -42,7 +42,7 @@ namespace SixLabors.ImageSharp.PixelFormats
             }
 
             /// <inheritdoc />
-            internal override void FromVector4(Configuration configuration, ReadOnlySpan<Vector4> sourceVectors, Span<Argb32> destPixels)
+            internal override void FromVector4(Configuration configuration, Span<Vector4> sourceVectors, Span<Argb32> destPixels)
             {
                 Vector4Converters.RgbaCompatible.FromVector4(configuration, this, sourceVectors, destPixels, false);
             }
@@ -54,7 +54,7 @@ namespace SixLabors.ImageSharp.PixelFormats
             }
 
             /// <inheritdoc />
-            internal override void FromScaledVector4(Configuration configuration, ReadOnlySpan<Vector4> sourceVectors, Span<Argb32> destPixels)
+            internal override void FromScaledVector4(Configuration configuration, Span<Vector4> sourceVectors, Span<Argb32> destPixels)
             {
                 Vector4Converters.RgbaCompatible.FromVector4(configuration, this, sourceVectors, destPixels, true);
             }

src/ImageSharp/PixelFormats/PixelImplementations/Generated/Bgr24.PixelOperations.Generated.cs

@@ -42,7 +42,7 @@ namespace SixLabors.ImageSharp.PixelFormats
             }
 
             /// <inheritdoc />
-            internal override void FromVector4(Configuration configuration, ReadOnlySpan<Vector4> sourceVectors, Span<Bgr24> destPixels)
+            internal override void FromVector4(Configuration configuration, Span<Vector4> sourceVectors, Span<Bgr24> destPixels)
             {
                 Vector4Converters.RgbaCompatible.FromVector4(configuration, this, sourceVectors, destPixels, false);
             }
@@ -54,7 +54,7 @@ namespace SixLabors.ImageSharp.PixelFormats
             }
 
             /// <inheritdoc />
-            internal override void FromScaledVector4(Configuration configuration, ReadOnlySpan<Vector4> sourceVectors, Span<Bgr24> destPixels)
+            internal override void FromScaledVector4(Configuration configuration, Span<Vector4> sourceVectors, Span<Bgr24> destPixels)
             {
                 Vector4Converters.RgbaCompatible.FromVector4(configuration, this, sourceVectors, destPixels, true);
             }

src/ImageSharp/PixelFormats/PixelImplementations/Generated/Bgra32.PixelOperations.Generated.cs

@@ -42,7 +42,7 @@ namespace SixLabors.ImageSharp.PixelFormats
             }
 
             /// <inheritdoc />
-            internal override void FromVector4(Configuration configuration, ReadOnlySpan<Vector4> sourceVectors, Span<Bgra32> destPixels)
+            internal override void FromVector4(Configuration configuration, Span<Vector4> sourceVectors, Span<Bgra32> destPixels)
             {
                 Vector4Converters.RgbaCompatible.FromVector4(configuration, this, sourceVectors, destPixels, false);
             }
@@ -54,7 +54,7 @@ namespace SixLabors.ImageSharp.PixelFormats
             }
 
             /// <inheritdoc />
-            internal override void FromScaledVector4(Configuration configuration, ReadOnlySpan<Vector4> sourceVectors, Span<Bgra32> destPixels)
+            internal override void FromScaledVector4(Configuration configuration, Span<Vector4> sourceVectors, Span<Bgra32> destPixels)
             {
                 Vector4Converters.RgbaCompatible.FromVector4(configuration, this, sourceVectors, destPixels, true);
             }

src/ImageSharp/PixelFormats/PixelImplementations/Generated/Rgb24.PixelOperations.Generated.cs

@@ -42,7 +42,7 @@ namespace SixLabors.ImageSharp.PixelFormats
             }
 
             /// <inheritdoc />
-            internal override void FromVector4(Configuration configuration, ReadOnlySpan<Vector4> sourceVectors, Span<Rgb24> destPixels)
+            internal override void FromVector4(Configuration configuration, Span<Vector4> sourceVectors, Span<Rgb24> destPixels)
             {
                 Vector4Converters.RgbaCompatible.FromVector4(configuration, this, sourceVectors, destPixels, false);
             }
@@ -54,7 +54,7 @@ namespace SixLabors.ImageSharp.PixelFormats
             }
 
             /// <inheritdoc />
-            internal override void FromScaledVector4(Configuration configuration, ReadOnlySpan<Vector4> sourceVectors, Span<Rgb24> destPixels)
+            internal override void FromScaledVector4(Configuration configuration, Span<Vector4> sourceVectors, Span<Rgb24> destPixels)
             {
                 Vector4Converters.RgbaCompatible.FromVector4(configuration, this, sourceVectors, destPixels, true);
             }

src/ImageSharp/PixelFormats/PixelImplementations/Generated/_Common.ttinclude

@@ -111,7 +111,7 @@ using System.Runtime.InteropServices;
     {
 #>
             /// <inheritdoc />
-            internal override void FromVector4(Configuration configuration, ReadOnlySpan<Vector4> sourceVectors, Span<<#=pixelType#>> destPixels)
+            internal override void FromVector4(Configuration configuration, Span<Vector4> sourceVectors, Span<<#=pixelType#>> destPixels)
             {
                 Vector4Converters.RgbaCompatible.FromVector4(configuration, this, sourceVectors, destPixels, false);
             }
@@ -123,7 +123,7 @@ using System.Runtime.InteropServices;
             }
 
             /// <inheritdoc />
-            internal override void FromScaledVector4(Configuration configuration, ReadOnlySpan<Vector4> sourceVectors, Span<<#=pixelType#>> destPixels)
+            internal override void FromScaledVector4(Configuration configuration, Span<Vector4> sourceVectors, Span<<#=pixelType#>> destPixels)
             {
                 Vector4Converters.RgbaCompatible.FromVector4(configuration, this, sourceVectors, destPixels, true);
             }

src/ImageSharp/PixelFormats/PixelImplementations/Rgba32.PixelOperations.cs

@@ -36,7 +36,7 @@ namespace SixLabors.ImageSharp.PixelFormats
             /// <inheritdoc />
             internal override void FromVector4(
                 Configuration configuration,
-                ReadOnlySpan<Vector4> sourceVectors,
+                Span<Vector4> sourceVectors,
                 Span<Rgba32> destPixels)
             {
                 Guard.DestinationShouldNotBeTooShort(sourceVectors, destPixels, nameof(destPixels));
@@ -60,7 +60,7 @@ namespace SixLabors.ImageSharp.PixelFormats
             /// <inheritdoc />
             internal override void FromScaledVector4(
                 Configuration configuration,
-                ReadOnlySpan<Vector4> sourceVectors,
+                Span<Vector4> sourceVectors,
                 Span<Rgba32> destinationColors)
             {
                 this.FromVector4(configuration, sourceVectors, destinationColors);

src/ImageSharp/PixelFormats/PixelImplementations/RgbaVector.PixelOperations.cs

@@ -20,7 +20,7 @@ namespace SixLabors.ImageSharp.PixelFormats
             /// <inheritdoc />
             internal override void FromScaledVector4(
                 Configuration configuration,
-                ReadOnlySpan<Vector4> sourceVectors,
+                Span<Vector4> sourceVectors,
                 Span<RgbaVector> destinationColors)
             {
                 Guard.DestinationShouldNotBeTooShort(sourceVectors, destinationColors, nameof(destinationColors));

src/ImageSharp/PixelFormats/PixelOperations{TPixel}.cs

@@ -9,6 +9,14 @@ using System.Runtime.InteropServices;
 
 namespace SixLabors.ImageSharp.PixelFormats
 {
+    internal enum PixelConversionModifiers
+    {
+        None = 0,
+        Scale = 1 << 0,
+        Premultiply = 1 << 1,
+        SRgbCompand = 1 << 2,
+    }
+
     /// <summary>
     /// A stateless class implementing Strategy Pattern for batched pixel-data conversion operations
     /// for pixel buffers of type <typeparamref name="TPixel"/>.
@@ -30,7 +38,7 @@ namespace SixLabors.ImageSharp.PixelFormats
         /// <param name="destPixels">The <see cref="Span{T}"/> to the destination colors.</param>
         internal virtual void FromVector4(
             Configuration configuration,
-            ReadOnlySpan<Vector4> sourceVectors,
+            Span<Vector4> sourceVectors,
             Span<TPixel> destPixels)
         {
             Guard.NotNull(configuration, nameof(configuration));
@@ -64,7 +72,7 @@ namespace SixLabors.ImageSharp.PixelFormats
         /// <param name="destinationColors">The <see cref="Span{T}"/> to the destination colors.</param>
         internal virtual void FromScaledVector4(
             Configuration configuration,
-            ReadOnlySpan<Vector4> sourceVectors,
+            Span<Vector4> sourceVectors,
             Span<TPixel> destinationColors)
         {
             Guard.NotNull(configuration, nameof(configuration));