Update version to 2.3.0 in Directory.Build.props

Bump the version number from 2.2.1 to 2.3.0 in the
Directory.Build.props file to reflect the latest changes.

.github/workflows/build.yml

@@ -14,9 +14,9 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - name: Setup .NET
-      uses: actions/setup-dotnet@v4.0.0
+      uses: actions/setup-dotnet@v4.3.1
       with:
-        dotnet-version: 8.0.x
+        dotnet-version: 9.0.x
     - name: Restore dependencies
       run: dotnet restore
     - name: Build

AssetRipper.TextureDecoder.Benchmarks/AssetRipper.TextureDecoder.Benchmarks.csproj

@@ -5,7 +5,7 @@
 	</PropertyGroup>
 
 	<ItemGroup>
-		<PackageReference Include="BenchmarkDotNet" Version="0.13.12" />
+		<PackageReference Include="BenchmarkDotNet" Version="0.14.0" />
 	</ItemGroup>
 
 	<ItemGroup>

AssetRipper.TextureDecoder.ColorGenerator/AssetRipper.TextureDecoder.ColorGenerator.csproj

@@ -5,7 +5,7 @@
 	</PropertyGroup>
 
 	<ItemGroup>
-		<PackageReference Include="AssetRipper.Text.SourceGeneration" Version="1.1.0" />
+		<PackageReference Include="AssetRipper.Text.SourceGeneration" Version="1.2.2" />
 	</ItemGroup>
 
 	<ItemGroup>

AssetRipper.TextureDecoder.TestGenerator/AssetRipper.TextureDecoder.TestGenerator.csproj

@@ -11,7 +11,7 @@
 	</ItemGroup>
 
 	<ItemGroup>
-		<PackageReference Include="AssetRipper.Text.SourceGeneration" Version="1.1.0" />
+		<PackageReference Include="AssetRipper.Text.SourceGeneration" Version="1.2.2" />
 	</ItemGroup>
 
 </Project>

AssetRipper.TextureDecoder.Tests/AssetRipper.TextureDecoder.Tests.csproj

@@ -5,14 +5,14 @@
 	</PropertyGroup>
 
 	<ItemGroup>
-		<PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.9.0" />
-		<PackageReference Include="NUnit" Version="4.1.0" />
-		<PackageReference Include="NUnit3TestAdapter" Version="4.5.0" />
-		<PackageReference Include="NUnit.Analyzers" Version="4.1.0">
+		<PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.13.0" />
+		<PackageReference Include="NUnit" Version="4.3.2" />
+		<PackageReference Include="NUnit3TestAdapter" Version="5.0.0" />
+		<PackageReference Include="NUnit.Analyzers" Version="4.6.0">
 			<PrivateAssets>all</PrivateAssets>
 			<IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
 		</PackageReference>
-		<PackageReference Include="coverlet.collector" Version="6.0.2">
+		<PackageReference Include="coverlet.collector" Version="6.0.4">
 		  <PrivateAssets>all</PrivateAssets>
 		  <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
 		</PackageReference>

AssetRipper.TextureDecoder.Tests/BcTests.cs

@@ -21,7 +21,7 @@ namespace AssetRipper.TextureDecoder.Tests
 		}
 		
 		[Test]
-		public void DecompressDXT1Test()
+		public void Decompress_BC1()
 		{
 			ReadOnlySpan<byte> data = File.ReadAllBytes(TestFileFolders.DxtTestFiles + "test.dxt1");
 			int totalBytesRead = 0;
@@ -36,7 +36,7 @@ namespace AssetRipper.TextureDecoder.Tests
 		}
 
 		[Test]
-		public void DecompressDXT3Test()
+		public void Decompress_BC2()
 		{
 			ReadOnlySpan<byte> data = File.ReadAllBytes(TestFileFolders.DxtTestFiles + "test.dxt3");
 			int totalBytesRead = 0;
@@ -51,7 +51,7 @@ namespace AssetRipper.TextureDecoder.Tests
 		}
 
 		[Test]
-		public void DecompressDXT5Test()
+		public void Decompress_BC3()
 		{
 			ReadOnlySpan<byte> data = File.ReadAllBytes(TestFileFolders.DxtTestFiles + "test.dxt5");
 			int totalBytesRead = 0;
@@ -66,7 +66,7 @@ namespace AssetRipper.TextureDecoder.Tests
 		}
 
 		[Test]
-		public void DecompressBC4Test()
+		public void Decompress_BC4()
 		{
 			ReadOnlySpan<byte> data = File.ReadAllBytes(TestFileFolders.BcTestFiles + "test.bc4");
 			int bytesRead = Bc4.Decompress(data, 512, 512, out _);
@@ -74,7 +74,7 @@ namespace AssetRipper.TextureDecoder.Tests
 		}
 
 		[Test]
-		public void DecompressBC5Test()
+		public void Decompress_BC5()
 		{
 			ReadOnlySpan<byte> data = File.ReadAllBytes(TestFileFolders.BcTestFiles + "test.bc5");
 			int bytesRead = Bc5.Decompress(data, 512, 512, out _);
@@ -84,7 +84,7 @@ namespace AssetRipper.TextureDecoder.Tests
 		[TestCase("test.bc6h_fast")]
 		[TestCase("test.bc6h_normal")]
 		[TestCase("test.bc6h_best")]
-		public void DecompressBC6HTest(string fileName)
+		public void Decompress_BC6H(string fileName)
 		{
 			AssertCorrectBC6HDecompression(TestFileFolders.BcTestFiles + fileName, 512, 512, false);
 		}
@@ -92,14 +92,85 @@ namespace AssetRipper.TextureDecoder.Tests
 		[TestCase("test.bc7_fast")]
 		[TestCase("test.bc7_normal")]
 		[TestCase("test.bc7_best")]
-		public void DecompressBC7Test(string fileName)
+		public void Decompress_BC7(string fileName)
 		{
 			AssertCorrectBC7Decompression(TestFileFolders.BcTestFiles + fileName, 512, 512);
 		}
 
 		[Test]
-		[Ignore("Not implemented")]
-		public void BC7PartialBlockTest([Range(1, 4)] int width, [Range(1, 4)] int height)
+		public void PartialBlock_BC1([Range(1, 4)] int width, [Range(1, 4)] int height)
+		{
+			Assert.Multiple(() =>
+			{
+				ReadOnlySpan<byte> data = File.ReadAllBytes(TestFileFolders.DxtTestFiles + "test.dxt1").AsSpan()[..Bc1.BlockSize];
+				int bytesRead = Bc1.Decompress(data, width, height, out byte[] decodedData);
+				Assert.That(bytesRead, Is.EqualTo(data.Length));
+				Assert.That(decodedData, Has.Length.EqualTo(width * height * Unsafe.SizeOf<ColorBGRA32>()));
+			});
+		}
+
+		[Test]
+		public void PartialBlock_BC2([Range(1, 4)] int width, [Range(1, 4)] int height)
+		{
+			Assert.Multiple(() =>
+			{
+				ReadOnlySpan<byte> data = File.ReadAllBytes(TestFileFolders.DxtTestFiles + "test.dxt3").AsSpan()[..Bc2.BlockSize];
+				int bytesRead = Bc2.Decompress(data, width, height, out byte[] decodedData);
+				Assert.That(bytesRead, Is.EqualTo(data.Length));
+				Assert.That(decodedData, Has.Length.EqualTo(width * height * Unsafe.SizeOf<ColorBGRA32>()));
+			});
+		}
+
+		[Test]
+		public void PartialBlock_BC3([Range(1, 4)] int width, [Range(1, 4)] int height)
+		{
+			Assert.Multiple(() =>
+			{
+				ReadOnlySpan<byte> data = File.ReadAllBytes(TestFileFolders.DxtTestFiles + "test.dxt5").AsSpan()[..Bc3.BlockSize];
+				int bytesRead = Bc3.Decompress(data, width, height, out byte[] decodedData);
+				Assert.That(bytesRead, Is.EqualTo(data.Length));
+				Assert.That(decodedData, Has.Length.EqualTo(width * height * Unsafe.SizeOf<ColorBGRA32>()));
+			});
+		}
+
+		[Test]
+		public void PartialBlock_BC4([Range(1, 4)] int width, [Range(1, 4)] int height)
+		{
+			Assert.Multiple(() =>
+			{
+				ReadOnlySpan<byte> data = File.ReadAllBytes(TestFileFolders.BcTestFiles + "test.bc4").AsSpan()[..Bc4.BlockSize];
+				int bytesRead = Bc4.Decompress(data, width, height, out byte[] decodedData);
+				Assert.That(bytesRead, Is.EqualTo(data.Length));
+				Assert.That(decodedData, Has.Length.EqualTo(width * height * Unsafe.SizeOf<ColorBGRA32>()));
+			});
+		}
+
+		[Test]
+		public void PartialBlock_BC5([Range(1, 4)] int width, [Range(1, 4)] int height)
+		{
+			Assert.Multiple(() =>
+			{
+				ReadOnlySpan<byte> data = File.ReadAllBytes(TestFileFolders.BcTestFiles + "test.bc5").AsSpan()[..Bc5.BlockSize];
+				int bytesRead = Bc5.Decompress(data, width, height, out byte[] decodedData);
+				Assert.That(bytesRead, Is.EqualTo(data.Length));
+				Assert.That(decodedData, Has.Length.EqualTo(width * height * Unsafe.SizeOf<ColorBGRA32>()));
+			});
+		}
+
+		[Test]
+		public void PartialBlock_BC6H([Range(1, 4)] int width, [Range(1, 4)] int height)
+		{
+			Assert.Multiple(() =>
+			{
+				ReadOnlySpan<byte> data = File.ReadAllBytes(TestFileFolders.BcTestFiles + "test.bc6h_best").AsSpan()[..Bc6h.BlockSize];
+				int bytesRead = Bc6h.Decompress(data, width, height, false, out byte[] decodedData);
+				Assert.That(bytesRead, Is.EqualTo(data.Length));
+				Assert.That(decodedData, Has.Length.EqualTo(width * height * Unsafe.SizeOf<ColorBGRA32>()));
+			});
+		}
+
+		[Test]
+		public void PartialBlock_BC7([Range(1, 4)] int width, [Range(1, 4)] int height)
 		{
 			Assert.Multiple(() =>
 			{

AssetRipper.TextureDecoder/Astc/AstcDecoder.cs

@@ -883,7 +883,7 @@ namespace AssetRipper.TextureDecoder.Astc
 		[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
 		private static int GetBits(ReadOnlySpan<byte> input, int bit, int len)
 		{
-			ReadOnlySpan<byte> slice = input[(bit / 8)..];
+			ReadOnlySpan<byte> slice = input[(bit / 8)..];
 			int bitBuffer;
 			if (slice.Length >= sizeof(int))
 			{
@@ -894,7 +894,7 @@ namespace AssetRipper.TextureDecoder.Astc
 				Span<byte> temp = stackalloc byte[sizeof(int)];
 				slice.CopyTo(temp);
 				bitBuffer = BinaryPrimitives.ReadInt32LittleEndian(temp);
-			}
+			}
 			return (bitBuffer >> (bit % 8)) & ((1 << len) - 1);
 		}
 
@@ -996,10 +996,12 @@ namespace AssetRipper.TextureDecoder.Astc
 		[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
 		private static byte SelectColor(int v0, int v1, int weight)
 		{
-			return (byte)(((((v0 << 8 | v0) * (64 - weight) + (v1 << 8 | v1) * weight + 32) >> 6) * 255 + 32768) / 65536);
+			const int SignAdjustment = short.MaxValue + 1;
+			const int MaxValue = ushort.MaxValue + 1;
+			return (byte)(((((v0 << 8 | v0) * (64 - weight) + (v1 << 8 | v1) * weight + 32) >> 6) * byte.MaxValue + SignAdjustment) / MaxValue);
 		}
 
-		private static readonly byte[] BitReverseTable =
+		private static ReadOnlySpan<byte> BitReverseTable =>
 		[
 			0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, 0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0,
 			0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8, 0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8,
@@ -1019,15 +1021,15 @@ namespace AssetRipper.TextureDecoder.Astc
 			0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF, 0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
 		];
 
-		private static readonly int[] WeightPrecTableA = [0, 0, 0, 3, 0, 5, 3, 0, 0, 0, 5, 3, 0, 5, 3, 0];
-		private static readonly int[] WeightPrecTableB = [0, 0, 1, 0, 2, 0, 1, 3, 0, 0, 1, 2, 4, 2, 3, 5];
+		private static ReadOnlySpan<int> WeightPrecTableA => [0, 0, 0, 3, 0, 5, 3, 0, 0, 0, 5, 3, 0, 5, 3, 0];
+		private static ReadOnlySpan<int> WeightPrecTableB => [0, 0, 1, 0, 2, 0, 1, 3, 0, 0, 1, 2, 4, 2, 3, 5];
 
-		private static readonly int[] CemTableA = [0, 3, 5, 0, 3, 5, 0, 3, 5, 0, 3, 5, 0, 3, 5, 0, 3, 0, 0];
-		private static readonly int[] CemTableB = [8, 6, 5, 7, 5, 4, 6, 4, 3, 5, 3, 2, 4, 2, 1, 3, 1, 2, 1];
+		private static ReadOnlySpan<int> CemTableA => [0, 3, 5, 0, 3, 5, 0, 3, 5, 0, 3, 5, 0, 3, 5, 0, 3, 0, 0];
+		private static ReadOnlySpan<int> CemTableB => [8, 6, 5, 7, 5, 4, 6, 4, 3, 5, 3, 2, 4, 2, 1, 3, 1, 2, 1];
 
-		private static readonly int[] DImt = [0, 2, 4, 5, 7];
-		private static readonly int[] DImq = [0, 3, 5];
-		private static readonly int[] DITritsTable =
+		private static ReadOnlySpan<int> DImt => [0, 2, 4, 5, 7];
+		private static ReadOnlySpan<int> DImq => [0, 3, 5];
+		private static ReadOnlySpan<int> DITritsTable =>
 		[
 			0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 2, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 0, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 2, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 1, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 2, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 2, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 2, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 2, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 2, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 0, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 2, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 1, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 2, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 2, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 2, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 2, 2, 0, 1, 2, 2,
 			0, 0, 0, 0, 1, 1, 1, 0, 2, 2, 2, 0, 2, 2, 2, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 2, 2, 2, 0, 2, 2, 2, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 2, 2, 2, 0, 2, 2, 2, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 1, 2, 2, 2, 0, 0, 0, 0, 0, 1, 1, 1, 0, 2, 2, 2, 0, 2, 2, 2, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 1, 2, 2, 2, 0, 0, 0, 0, 0, 1, 1, 1, 0, 2, 2, 2, 0, 2, 2, 2, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 2, 2, 2, 0, 2, 2, 2, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 2, 2, 2, 0, 2, 2, 2, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 1, 2, 2, 2, 1, 0, 0, 0, 0, 1, 1, 1, 0, 2, 2, 2, 0, 2, 2, 2, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 1, 2, 2, 2, 1,
@@ -1035,14 +1037,14 @@ namespace AssetRipper.TextureDecoder.Astc
 			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2,
 			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
 		];
-		private static readonly int[] DIQuintsTable =
+		private static ReadOnlySpan<int> DIQuintsTable =>
 		[
 			0, 1, 2, 3, 4, 0, 4, 4, 0, 1, 2, 3, 4, 1, 4, 4, 0, 1, 2, 3, 4, 2, 4, 4, 0, 1, 2, 3, 4, 3, 4, 4, 0, 1, 2, 3, 4, 0, 4, 0, 0, 1, 2, 3, 4, 1, 4, 1, 0, 1, 2, 3, 4, 2, 4, 2, 0, 1, 2, 3, 4, 3, 4, 3, 0, 1, 2, 3, 4, 0, 2, 3, 0, 1, 2, 3, 4, 1, 2, 3, 0, 1, 2, 3, 4, 2, 2, 3, 0, 1, 2, 3, 4, 3, 2, 3, 0, 1, 2, 3, 4, 0, 0, 1, 0, 1, 2, 3, 4, 1, 0, 1, 0, 1, 2, 3, 4, 2, 0, 1, 0, 1, 2, 3, 4, 3, 0, 1,
 			0, 0, 0, 0, 0, 4, 4, 4, 1, 1, 1, 1, 1, 4, 4, 4, 2, 2, 2, 2, 2, 4, 4, 4, 3, 3, 3, 3, 3, 4, 4, 4, 0, 0, 0, 0, 0, 4, 0, 4, 1, 1, 1, 1, 1, 4, 1, 4, 2, 2, 2, 2, 2, 4, 2, 4, 3, 3, 3, 3, 3, 4, 3, 4, 0, 0, 0, 0, 0, 4, 0, 0, 1, 1, 1, 1, 1, 4, 1, 1, 2, 2, 2, 2, 2, 4, 2, 2, 3, 3, 3, 3, 3, 4, 3, 3, 0, 0, 0, 0, 0, 4, 0, 0, 1, 1, 1, 1, 1, 4, 1, 1, 2, 2, 2, 2, 2, 4, 2, 2, 3, 3, 3, 3, 3, 4, 3, 3,
 			0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 1, 4, 0, 0, 0, 0, 0, 0, 2, 4, 0, 0, 0, 0, 0, 0, 3, 4, 1, 1, 1, 1, 1, 1, 4, 4, 1, 1, 1, 1, 1, 1, 4, 4, 1, 1, 1, 1, 1, 1, 4, 4, 1, 1, 1, 1, 1, 1, 4, 4, 2, 2, 2, 2, 2, 2, 4, 4, 2, 2, 2, 2, 2, 2, 4, 4, 2, 2, 2, 2, 2, 2, 4, 4, 2, 2, 2, 2, 2, 2, 4, 4, 3, 3, 3, 3, 3, 3, 4, 4, 3, 3, 3, 3, 3, 3, 4, 4, 3, 3, 3, 3, 3, 3, 4, 4, 3, 3, 3, 3, 3, 3, 4, 4,
 		];
 
-		private static readonly int[] DETritsTable = [0, 204, 93, 44, 22, 11, 5];
-		private static readonly int[] DEQuintsTable = [0, 113, 54, 26, 13, 6];
+		private static ReadOnlySpan<int> DETritsTable => [0, 204, 93, 44, 22, 11, 5];
+		private static ReadOnlySpan<int> DEQuintsTable => [0, 113, 54, 26, 13, 6];
 	}
 }

AssetRipper.TextureDecoder/Atc/AtcDecoder.cs

@@ -121,6 +121,7 @@ namespace AssetRipper.TextureDecoder.Atc
 		[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
 		private static T ReadAtOffset<T>(this ReadOnlySpan<byte> input, int offset) where T : unmanaged
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			return MemoryMarshal.Read<T>(input.Slice(offset));
 		}
 

AssetRipper.TextureDecoder/Bc/Bc1.cs

@@ -9,6 +9,22 @@ public static class Bc1
 	/// The size of an encoded block, in bytes.
 	/// </summary>
 	public const int BlockSize = 8;
+	/// <summary>
+	/// The width of a decoded block, in pixels.
+	/// </summary>
+	private const int BlockWidth = 4;
+	/// <summary>
+	/// The height of a decoded block, in pixels.
+	/// </summary>
+	private const int BlockHeight = 4;
+	/// <summary>
+	/// The size of the natural pixel type.
+	/// </summary>
+	private static int PixelSize => Unsafe.SizeOf<ColorRGBA<byte>>();
+	/// <summary>
+	/// The size of a decoded block, in bytes.
+	/// </summary>
+	internal static int DecodedBlockSize => BlockWidth * BlockHeight * PixelSize;
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, out byte[] output)
 	{
@@ -18,13 +34,14 @@ public static class Bc1
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 	{
+		Span<byte> buffer = stackalloc byte[DecodedBlockSize];
 		int inputOffset = 0;
-		for (int i = 0; i < height; i += 4)
+		for (int i = 0; i < height; i += BlockHeight)
 		{
-			for (int j = 0; j < width; j += 4)
+			for (int j = 0; j < width; j += BlockWidth)
 			{
-				int outputOffset = ((i * width) + j) * Unsafe.SizeOf<ColorRGBA<byte>>();
-				BcHelpers.DecompressBc1(input.Slice(inputOffset, BlockSize), output.Slice(outputOffset), width * 4);
+				BcHelpers.DecompressBc1(input.Slice(inputOffset, BlockSize), buffer);
+				BcHelpers.CopyBufferToOutput(buffer, output, width, height, j, i, BlockWidth, BlockHeight, PixelSize);
 				inputOffset += BlockSize;
 			}
 		}

AssetRipper.TextureDecoder/Bc/Bc2.cs

@@ -9,6 +9,22 @@ public static class Bc2
 	/// The size of an encoded block, in bytes.
 	/// </summary>
 	public const int BlockSize = 16;
+	/// <summary>
+	/// The width of a decoded block, in pixels.
+	/// </summary>
+	private const int BlockWidth = 4;
+	/// <summary>
+	/// The height of a decoded block, in pixels.
+	/// </summary>
+	private const int BlockHeight = 4;
+	/// <summary>
+	/// The size of the natural pixel type.
+	/// </summary>
+	private static int PixelSize => Unsafe.SizeOf<ColorRGBA<byte>>();
+	/// <summary>
+	/// The size of a decoded block, in bytes.
+	/// </summary>
+	internal static int DecodedBlockSize => BlockWidth * BlockHeight * PixelSize;
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, out byte[] output)
 	{
@@ -18,13 +34,14 @@ public static class Bc2
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 	{
+		Span<byte> buffer = stackalloc byte[DecodedBlockSize];
 		int inputOffset = 0;
-		for (int i = 0; i < height; i += 4)
+		for (int i = 0; i < height; i += BlockHeight)
 		{
-			for (int j = 0; j < width; j += 4)
+			for (int j = 0; j < width; j += BlockWidth)
 			{
-				int outputOffset = ((i * width) + j) * Unsafe.SizeOf<ColorRGBA<byte>>();
-				BcHelpers.DecompressBc2(input.Slice(inputOffset), output.Slice(outputOffset), width * 4);
+				BcHelpers.DecompressBc2(input.Slice(inputOffset), buffer);
+				BcHelpers.CopyBufferToOutput(buffer, output, width, height, j, i, BlockWidth, BlockHeight, PixelSize);
 				inputOffset += BlockSize;
 			}
 		}

AssetRipper.TextureDecoder/Bc/Bc3.cs

@@ -9,6 +9,22 @@ public static class Bc3
 	/// The size of an encoded block, in bytes.
 	/// </summary>
 	public const int BlockSize = 16;
+	/// <summary>
+	/// The width of a decoded block, in pixels.
+	/// </summary>
+	private const int BlockWidth = 4;
+	/// <summary>
+	/// The height of a decoded block, in pixels.
+	/// </summary>
+	private const int BlockHeight = 4;
+	/// <summary>
+	/// The size of the natural pixel type.
+	/// </summary>
+	private static int PixelSize => Unsafe.SizeOf<ColorRGBA<byte>>();
+	/// <summary>
+	/// The size of a decoded block, in bytes.
+	/// </summary>
+	internal static int DecodedBlockSize => BlockWidth * BlockHeight * PixelSize;
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, out byte[] output)
 	{
@@ -18,13 +34,14 @@ public static class Bc3
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 	{
+		Span<byte> buffer = stackalloc byte[DecodedBlockSize];
 		int inputOffset = 0;
-		for (int i = 0; i < height; i += 4)
+		for (int i = 0; i < height; i += BlockHeight)
 		{
-			for (int j = 0; j < width; j += 4)
+			for (int j = 0; j < width; j += BlockWidth)
 			{
-				int outputOffset = ((i * width) + j) * Unsafe.SizeOf<ColorRGBA<byte>>();
-				BcHelpers.DecompressBc3(input.Slice(inputOffset), output.Slice(outputOffset), width * 4);
+				BcHelpers.DecompressBc3(input.Slice(inputOffset), buffer);
+				BcHelpers.CopyBufferToOutput(buffer, output, width, height, j, i, BlockWidth, BlockHeight, PixelSize);
 				inputOffset += BlockSize;
 			}
 		}

AssetRipper.TextureDecoder/Bc/Bc4.cs

@@ -10,6 +10,22 @@ public static class Bc4
 	/// The size of an encoded block, in bytes.
 	/// </summary>
 	public const int BlockSize = 8;
+	/// <summary>
+	/// The width of a decoded block, in pixels.
+	/// </summary>
+	private const int BlockWidth = 4;
+	/// <summary>
+	/// The height of a decoded block, in pixels.
+	/// </summary>
+	private const int BlockHeight = 4;
+	/// <summary>
+	/// The size of the natural pixel type.
+	/// </summary>
+	private static int PixelSize => Unsafe.SizeOf<ColorR<byte>>();
+	/// <summary>
+	/// The size of a decoded block, in bytes.
+	/// </summary>
+	internal static int DecodedBlockSize => BlockWidth * BlockHeight * PixelSize;
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, out byte[] output)
 	{
@@ -19,21 +35,22 @@ public static class Bc4
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 	{
-		int bufferSize = width * height * Unsafe.SizeOf<ColorR<byte>>();
-		byte[] bufferArray = ArrayPool<byte>.Shared.Rent(bufferSize);
-		Span<byte> buffer = new Span<byte>(bufferArray, 0, bufferSize);
+		int naturalSize = width * height * PixelSize;
+		byte[] rentedArray = ArrayPool<byte>.Shared.Rent(naturalSize);
+		Span<byte> naturalPixels = new Span<byte>(rentedArray, 0, naturalSize);
+		Span<byte> buffer = stackalloc byte[DecodedBlockSize];
 		int inputOffset = 0;
-		for (int i = 0; i < height; i += 4)
+		for (int i = 0; i < height; i += BlockHeight)
 		{
-			for (int j = 0; j < width; j += 4)
+			for (int j = 0; j < width; j += BlockWidth)
 			{
-				int bufferOffset = ((i * width) + j) * Unsafe.SizeOf<ColorR<byte>>();
-				BcHelpers.DecompressBc4(input.Slice(inputOffset), buffer.Slice(bufferOffset), width);
+				BcHelpers.DecompressBc4(input.Slice(inputOffset), buffer);
+				BcHelpers.CopyBufferToOutput(buffer, naturalPixels, width, height, j, i, BlockWidth, BlockHeight, PixelSize);
 				inputOffset += BlockSize;
 			}
 		}
-		RgbConverter.Convert<ColorR<byte>, byte, ColorBGRA32, byte>(buffer, width, height, output);
-		ArrayPool<byte>.Shared.Return(bufferArray);
+		RgbConverter.Convert<ColorR<byte>, byte, ColorBGRA32, byte>(naturalPixels, width, height, output);
+		ArrayPool<byte>.Shared.Return(rentedArray);
 		return inputOffset;
 	}
 

AssetRipper.TextureDecoder/Bc/Bc5.cs

@@ -10,6 +10,22 @@ public static class Bc5
 	/// The size of an encoded block, in bytes.
 	/// </summary>
 	public const int BlockSize = 16;
+	/// <summary>
+	/// The width of a decoded block, in pixels.
+	/// </summary>
+	private const int BlockWidth = 4;
+	/// <summary>
+	/// The height of a decoded block, in pixels.
+	/// </summary>
+	private const int BlockHeight = 4;
+	/// <summary>
+	/// The size of the natural pixel type.
+	/// </summary>
+	private static int PixelSize => Unsafe.SizeOf<ColorRG<byte>>();
+	/// <summary>
+	/// The size of a decoded block, in bytes.
+	/// </summary>
+	internal static int DecodedBlockSize => BlockWidth * BlockHeight * PixelSize;
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, out byte[] output)
 	{
@@ -19,21 +35,22 @@ public static class Bc5
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 	{
-		int bufferSize = width * height * Unsafe.SizeOf<ColorRG<byte>>();
-		byte[] bufferArray = ArrayPool<byte>.Shared.Rent(bufferSize);
-		Span<byte> buffer = new Span<byte>(bufferArray, 0, bufferSize);
+		int naturalSize = width * height * PixelSize;
+		byte[] rentedArray = ArrayPool<byte>.Shared.Rent(naturalSize);
+		Span<byte> naturalPixels = new Span<byte>(rentedArray, 0, naturalSize);
+		Span<byte> buffer = stackalloc byte[DecodedBlockSize];
 		int inputOffset = 0;
-		for (int i = 0; i < height; i += 4)
+		for (int i = 0; i < height; i += BlockHeight)
 		{
-			for (int j = 0; j < width; j += 4)
+			for (int j = 0; j < width; j += BlockWidth)
 			{
-				int bufferOffset = ((i * width) + j) * Unsafe.SizeOf<ColorRG<byte>>();
-				BcHelpers.DecompressBc5(input.Slice(inputOffset), buffer.Slice(bufferOffset), width * 2);
+				BcHelpers.DecompressBc5(input.Slice(inputOffset), buffer);
+				BcHelpers.CopyBufferToOutput(buffer, naturalPixels, width, height, j, i, BlockWidth, BlockHeight, PixelSize);
 				inputOffset += BlockSize;
 			}
 		}
-		RgbConverter.Convert<ColorRG<byte>, byte, ColorBGRA32, byte>(buffer, width, height, output);
-		ArrayPool<byte>.Shared.Return(bufferArray);
+		RgbConverter.Convert<ColorRG<byte>, byte, ColorBGRA32, byte>(naturalPixels, width, height, output);
+		ArrayPool<byte>.Shared.Return(rentedArray);
 		return inputOffset;
 	}
 

AssetRipper.TextureDecoder/Bc/Bc6h.cs

@@ -10,6 +10,23 @@ public static class Bc6h
 	/// The size of an encoded block, in bytes.
 	/// </summary>
 	public const int BlockSize = 16;
+	/// <summary>
+	/// The width of a decoded block, in pixels.
+	/// </summary>
+	private const int BlockWidth = 4;
+	/// <summary>
+	/// The height of a decoded block, in pixels.
+	/// </summary>
+	private const int BlockHeight = 4;
+	/// <summary>
+	/// The size of the natural pixel type.
+	/// </summary>
+	private static int PixelSize => Unsafe.SizeOf<ColorRGB<Half>>();
+	/// <summary>
+	/// The size of a decoded block, in bytes.
+	/// </summary>
+	internal static int DecodedBlockSize => BlockWidth * BlockHeight * PixelSize;
+
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, bool isSigned, out byte[] output)
 	{
@@ -19,25 +36,27 @@ public static class Bc6h
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, bool isSigned, Span<byte> output)
 	{
-		int bufferSize = width * height * Unsafe.SizeOf<ColorRGB<Half>>();
-		byte[] bufferArray = ArrayPool<byte>.Shared.Rent(bufferSize);
-		Span<byte> buffer = new Span<byte>(bufferArray, 0, bufferSize);
+		int naturalSize = width * height * PixelSize;
+		byte[] rentedArray = ArrayPool<byte>.Shared.Rent(naturalSize);
+		Span<byte> naturalPixels = new Span<byte>(rentedArray, 0, naturalSize);
+		Span<byte> buffer = stackalloc byte[DecodedBlockSize];
 		int inputOffset = 0;
-		for (int i = 0; i < height; i += 4)
+		for (int i = 0; i < height; i += BlockHeight)
 		{
-			for (int j = 0; j < width; j += 4)
+			for (int j = 0; j < width; j += BlockWidth)
 			{
-				int outputOffset = ((i * width) + j) * Unsafe.SizeOf<ColorRGB<Half>>();
 				BcHelpers.DecompressBc6h(
 					input.Slice(inputOffset, BlockSize),
-					buffer.Slice(outputOffset),
-					width * 3,
+					buffer,
 					isSigned);
+
+				BcHelpers.CopyBufferToOutput(buffer, naturalPixels, width, height, j, i, BlockWidth, BlockHeight, PixelSize);
+
 				inputOffset += BlockSize;
 			}
 		}
-		RgbConverter.Convert<ColorRGB<Half>, Half, ColorBGRA32, byte>(buffer, width, height, output);
-		ArrayPool<byte>.Shared.Return(bufferArray);
+		RgbConverter.Convert<ColorRGB<Half>, Half, ColorBGRA32, byte>(naturalPixels, width, height, output);
+		ArrayPool<byte>.Shared.Return(rentedArray);
 		return inputOffset;
 	}
 

AssetRipper.TextureDecoder/Bc/Bc6hTables.cs

@@ -211,7 +211,7 @@ internal static class Bc6hTables
 		]
 	];
 
-	internal static int[] AWeight3 { get; } = [0, 9, 18, 27, 37, 46, 55, 64];
+	internal static ReadOnlySpan<int> AWeight3 => [0, 9, 18, 27, 37, 46, 55, 64];
 
-	internal static int[] AWeight4 { get; } = [0, 4, 9, 13, 17, 21, 26, 30, 34, 38, 43, 47, 51, 55, 60, 64];
+	internal static ReadOnlySpan<int> AWeight4 => [0, 4, 9, 13, 17, 21, 26, 30, 34, 38, 43, 47, 51, 55, 60, 64];
 }

AssetRipper.TextureDecoder/Bc/Bc7.cs

@@ -21,6 +21,10 @@ public static class Bc7
 	/// The size of the natural pixel type.
 	/// </summary>
 	private static int PixelSize => Unsafe.SizeOf<ColorRGBA<byte>>();
+	/// <summary>
+	/// The size of a decoded block, in bytes.
+	/// </summary>
+	internal static int DecodedBlockSize => BlockWidth * BlockHeight * PixelSize;
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, out byte[] output)
 	{
@@ -30,16 +34,19 @@ public static class Bc7
 
 	public static int Decompress(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 	{
+		Span<byte> buffer = stackalloc byte[DecodedBlockSize];
+
 		int inputOffset = 0;
 		for (int i = 0; i < height; i += BlockHeight)
 		{
 			for (int j = 0; j < width; j += BlockWidth)
 			{
-				int outputOffset = ((i * width) + j) * PixelSize;
 				BcHelpers.DecompressBc7(
 					input.Slice(inputOffset, BlockSize),
-					output.Slice(outputOffset),
-					width * 4);
+					buffer);
+
+				BcHelpers.CopyBufferToOutput(buffer, output, width, height, j, i, BlockWidth, BlockHeight, PixelSize);
+
 				inputOffset += BlockSize;
 			}
 		}

AssetRipper.TextureDecoder/Bc/Bc7Tables.cs

@@ -789,11 +789,11 @@ internal static class Bc7Tables
 		]
 	];
 
-	internal static int[] AWeight2 { get; } = [0, 21, 43, 64];
+	internal static ReadOnlySpan<int> AWeight2 => [0, 21, 43, 64];
 
-	internal static int[] AWeight3 { get; } = [0, 9, 18, 27, 37, 46, 55, 64];
+	internal static ReadOnlySpan<int> AWeight3 => [0, 9, 18, 27, 37, 46, 55, 64];
 
-	internal static int[] AWeight4 { get; } = [0, 4, 9, 13, 17, 21, 26, 30, 34, 38, 43, 47, 51, 55, 60, 64];
+	internal static ReadOnlySpan<int> AWeight4 => [0, 4, 9, 13, 17, 21, 26, 30, 34, 38, 43, 47, 51, 55, 60, 64];
 
 	internal const byte bcdec_bc7_sModeHasPBits = 0b11001011;
 }

AssetRipper.TextureDecoder/Bc/BcHelpers.cs

@@ -1,47 +1,56 @@
 using System.Buffers.Binary;
+using System.Diagnostics;
 
 namespace AssetRipper.TextureDecoder.Bc;
 
 internal static class BcHelpers
 {
-	public static void DecompressBc1(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock, int destinationPitch)
+	public static void DecompressBc1(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock)
 	{
+		Debug.Assert(decompressedBlock.Length == Bc1.DecodedBlockSize);
+		int destinationPitch = 4 * 4;
 		ColorBlock(compressedBlock, decompressedBlock, destinationPitch, 0);
 	}
 
-	public static void DecompressBc2(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock, int destinationPitch)
+	public static void DecompressBc2(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock)
 	{
+		Debug.Assert(decompressedBlock.Length == Bc2.DecodedBlockSize);
+		int destinationPitch = 4 * 4;
 		ColorBlock(compressedBlock.Slice(8), decompressedBlock, destinationPitch, 1);
 		SharpAlphaBlock(compressedBlock, decompressedBlock.Slice(3), destinationPitch);
 	}
 
-	public static void DecompressBc3(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock, int destinationPitch)
+	public static void DecompressBc3(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock)
 	{
+		Debug.Assert(decompressedBlock.Length == Bc3.DecodedBlockSize);
+		int destinationPitch = 4 * 4;
 		ColorBlock(compressedBlock.Slice(8), decompressedBlock, destinationPitch, 1);
 		SmoothAlphaBlock(compressedBlock, decompressedBlock.Slice(3), destinationPitch, 4);
 	}
 
-	public static void DecompressBc4(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock, int destinationPitch)
+	public static void DecompressBc4(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock)
 	{
+		Debug.Assert(decompressedBlock.Length == Bc4.DecodedBlockSize);
+		int destinationPitch = 4 * 1;
 		SmoothAlphaBlock(compressedBlock, decompressedBlock, destinationPitch, 1);
 	}
 
-	public static void DecompressBc5(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock, int destinationPitch)
+	public static void DecompressBc5(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock)
 	{
+		Debug.Assert(decompressedBlock.Length == Bc5.DecodedBlockSize);
+		int destinationPitch = 4 * 2;
 		SmoothAlphaBlock(compressedBlock, decompressedBlock, destinationPitch, 2);
 		SmoothAlphaBlock(compressedBlock.Slice(8), decompressedBlock.Slice(1), destinationPitch, 2);
 	}
 
-	public static void DecompressBc6h(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock, int destinationPitch, bool isSigned)
+	public static void DecompressBc6h(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock, bool isSigned)
 	{
-		BitStream bstream = new()
-		{
-			low = BinaryPrimitives.ReadUInt64LittleEndian(compressedBlock),
-			high = BinaryPrimitives.ReadUInt64LittleEndian(compressedBlock.Slice(sizeof(ulong)))
-		};
-		Span<int> r = stackalloc int[4]; // wxyz
-		Span<int> g = stackalloc int[4];
-		Span<int> b = stackalloc int[4];
+		Debug.Assert(decompressedBlock.Length == Bc6h.DecodedBlockSize);
+
+		BitStream bstream = new(compressedBlock);
+		Span<uint> r = stackalloc uint[4]; // wxyz
+		Span<uint> g = stackalloc uint[4];
+		Span<uint> b = stackalloc uint[4];
 
 		int decompressedOffset = 0;
 
@@ -52,7 +61,7 @@ internal static class BcHelpers
 		int mode;
 
 		//modes >= 11 (10 in my code) are using 0 one, others will read it from the bitstream
-		int partition;
+		uint partition;
 
 		switch (ReadBc6hModeBits(ref bstream))
 		{
@@ -452,15 +461,7 @@ internal static class BcHelpers
 					// Do not use these in your encoder. If the hardware is passed blocks
 					// with one of these modes specified, the resulting decompressed block
 					// must contain all zeroes in all channels except for the alpha channel.
-					for (int i = 0; i < 4; ++i)
-					{
-						for (int j = 0; j < 4; ++j)
-						{
-							Span<byte> pixel = decompressedBlock.Slice(decompressedOffset + (j * 3 * sizeof(ushort)), 3 * sizeof(ushort));
-							pixel.Clear();
-						}
-						decompressedOffset += destinationPitch * sizeof(ushort);
-					}
+					decompressedBlock.Clear();
 
 					return;
 				}
@@ -477,7 +478,7 @@ internal static class BcHelpers
 
 		// Mode 11 (like Mode 10) does not use delta compression,
 		// and instead stores both color endpoints explicitly.
-		if ((mode != 9 && mode != 10) || isSigned)
+		if ((mode is not 9 and not 10) || isSigned)
 		{
 			for (int i = 1; i < (numPartitions + 1) * 2; ++i)
 			{
@@ -487,7 +488,7 @@ internal static class BcHelpers
 			}
 		}
 
-		if (mode != 9 && mode != 10)
+		if (mode is not 9 and not 10)
 		{
 			for (int i = 1; i < (numPartitions + 1) * 2; ++i)
 			{
@@ -520,7 +521,7 @@ internal static class BcHelpers
 				}
 				partitionSet &= 0x01;
 
-				int index = bstream.ReadBits(indexBits);
+				int index = bstream.ReadBits(indexBits).ToSigned();
 
 				int ep_i = (partitionSet * 2);
 
@@ -539,15 +540,15 @@ internal static class BcHelpers
 				BinaryPrimitives.WriteUInt16LittleEndian(decompressedBlock.Slice(bOffset), bFinal);
 			}
 
-			decompressedOffset += destinationPitch * sizeof(ushort);
+			decompressedOffset += 4 * 3 * sizeof(ushort);
 		}
 
-		static int ReadBc6hModeBits(ref BitStream bstream)
+		static uint ReadBc6hModeBits(ref BitStream bstream)
 		{
-			int twoBits = bstream.ReadBits(2);
+			uint twoBits = bstream.ReadBits(2);
 			if (twoBits > 1)
 			{
-				int threeBits = bstream.ReadBits(3);
+				uint threeBits = bstream.ReadBits(3);
 				return (threeBits << 2) | twoBits;
 			}
 			else
@@ -557,61 +558,54 @@ internal static class BcHelpers
 		}
 	}
 
-	public static void DecompressBc7(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock, int destinationPitch)
+	public static void DecompressBc7(ReadOnlySpan<byte> compressedBlock, Span<byte> decompressedBlock)
 	{
-		BitStream bstream = new()
-		{
-			low = BinaryPrimitives.ReadUInt64LittleEndian(compressedBlock),
-			high = BinaryPrimitives.ReadUInt64LittleEndian(compressedBlock.Slice(sizeof(ulong)))
-		};
-		Span2D<int> endpoints = new(stackalloc int[6 * 4], 6, 4);
-		Span2D<int> indices = new(stackalloc int[4 * 4], 4, 4);
+		Debug.Assert(decompressedBlock.Length == Bc7.DecodedBlockSize);
 
-		int decompressedOffset = 0;
+		BitStream bstream = new(compressedBlock);
+		Span2D<uint> endpoints = new(stackalloc uint[6 * 4], 6, 4);
+		Span2D<int> indices = new(stackalloc int[4 * 4], 4, 4);
 
 		int mode = ReadBc7Mode(ref bstream);
 
 		// unexpected mode, clear the block (transparent black)
 		if (mode >= 8)
 		{
-			for (int i = 0; i < 4; ++i)
-			{
-				for (int j = 0; j < 4; ++j)
-				{
-					decompressedBlock[decompressedOffset + (j * 4) + 0] = 0;
-					decompressedBlock[decompressedOffset + (j * 4) + 1] = 0;
-					decompressedBlock[decompressedOffset + (j * 4) + 2] = 0;
-					decompressedBlock[decompressedOffset + (j * 4) + 3] = 0;
-				}
-				decompressedOffset += destinationPitch;
-			}
+			decompressedBlock.Clear();
 
 			return;
 		}
 
-		int partition = 0;
+		uint partition = 0;
 		int numPartitions = 1;
-		int rotation = 0;
-		int indexSelectionBit = 0;
+		uint rotation = 0;
+		uint indexSelectionBit = 0;
 
-		if (mode == 0 || mode == 1 || mode == 2 || mode == 3 || mode == 7)
+		switch (mode)
 		{
-			numPartitions = (mode == 0 || mode == 2) ? 3 : 2;
-			partition = bstream.ReadBits((mode == 0) ? 4 : 6);
+			case 0:
+				numPartitions = 3;
+				partition = bstream.ReadBits(4);
+				break;
+			case 1 or 3 or 7:
+				numPartitions = 2;
+				partition = bstream.ReadBits(6);
+				break;
+			case 2:
+				numPartitions = 3;
+				partition = bstream.ReadBits(6);
+				break;
+			case 4:
+				rotation = bstream.ReadBits(2);
+				indexSelectionBit = bstream.ReadBit();
+				break;
+			case 5:
+				rotation = bstream.ReadBits(2);
+				break;
 		}
 
 		int numEndpoints = numPartitions * 2;
 
-		if (mode == 4 || mode == 5)
-		{
-			rotation = bstream.ReadBits(2);
-
-			if (mode == 4)
-			{
-				indexSelectionBit = bstream.ReadBit();
-			}
-		}
-
 		// Extract endpoints 
 		// RGB 
 		for (int i = 0; i < 3; ++i)
@@ -646,8 +640,8 @@ internal static class BcHelpers
 			// if P-bit is shared 
 			if (mode == 1)
 			{
-				int i = bstream.ReadBit();
-				int j = bstream.ReadBit();
+				uint i = bstream.ReadBit();
+				uint j = bstream.ReadBit();
 
 				// rgb component-wise insert pbits 
 				for (int k = 0; k < 3; ++k)
@@ -663,7 +657,7 @@ internal static class BcHelpers
 				// unique P-bit per endpoint 
 				for (int i = 0; i < numEndpoints; ++i)
 				{
-					int j = bstream.ReadBit();
+					uint j = bstream.ReadBit();
 					for (int k = 0; k < 4; ++k)
 					{
 						endpoints[i, k] |= j;
@@ -705,10 +699,25 @@ internal static class BcHelpers
 		}
 
 		// Determine weights tables 
-		int indexBits = (mode == 0 || mode == 1) ? 3 : ((mode == 6) ? 4 : 2);
-		int indexBits2 = (mode == 4) ? 3 : ((mode == 5) ? 2 : 0);
-		int[] weights = (indexBits == 2) ? Bc7Tables.AWeight2 : ((indexBits == 3) ? Bc7Tables.AWeight3 : Bc7Tables.AWeight4);
-		int[] weights2 = (indexBits2 == 2) ? Bc7Tables.AWeight2 : Bc7Tables.AWeight3;
+		int indexBits = mode switch
+		{
+			0 or 1 => 3,
+			6 => 4,
+			_ => 2
+		};
+		int indexBits2 = mode switch
+		{
+			4 => 3,
+			5 => 2,
+			_ => 0
+		};
+		ReadOnlySpan<int> weights = indexBits switch
+		{
+			2 => Bc7Tables.AWeight2,
+			3 => Bc7Tables.AWeight3,
+			_ => Bc7Tables.AWeight4
+		};
+		ReadOnlySpan<int> weights2 = (indexBits2 == 2) ? Bc7Tables.AWeight2 : Bc7Tables.AWeight3;
 
 		// Quite inconvenient that indices aren't interleaved so we have to make 2 passes here 
 		// Pass #1: collecting color indices 
@@ -726,7 +735,7 @@ internal static class BcHelpers
 					indexBits--;
 				}
 
-				indices[i, j] = bstream.ReadBits(indexBits);
+				indices[i, j] = bstream.ReadBits(indexBits).ToSigned();
 			}
 		}
 
@@ -742,10 +751,10 @@ internal static class BcHelpers
 
 				int index = indices[i, j];
 
-				int r;
-				int g;
-				int b;
-				int a;
+				uint r;
+				uint g;
+				uint b;
+				uint a;
 
 				if (indexBits2 == 0)
 				{
@@ -756,7 +765,7 @@ internal static class BcHelpers
 				}
 				else
 				{
-					int index2 = bstream.ReadBits((i | j) != 0 ? indexBits2 : (indexBits2 - 1));
+					int index2 = bstream.ReadBits((i | j) != 0 ? indexBits2 : (indexBits2 - 1)).ToSigned();
 					// The index value for interpolating color comes from the secondary index bits for the texel
 					// if the mode has an index selection bit and its value is one, and from the primary index bits otherwise.
 					// The alpha index comes from the secondary index bits if the block has a secondary index
@@ -800,23 +809,23 @@ internal static class BcHelpers
 						break;
 				}
 
-				decompressedBlock[decompressedOffset + (j * 4) + 0] = (byte)r;
-				decompressedBlock[decompressedOffset + (j * 4) + 1] = (byte)g;
-				decompressedBlock[decompressedOffset + (j * 4) + 2] = (byte)b;
-				decompressedBlock[decompressedOffset + (j * 4) + 3] = (byte)a;
+				int offset = (i * 16) + (j * 4);
+				decompressedBlock[offset + 0] = (byte)r;
+				decompressedBlock[offset + 1] = (byte)g;
+				decompressedBlock[offset + 2] = (byte)b;
+				decompressedBlock[offset + 3] = (byte)a;
 			}
-
-			decompressedOffset += destinationPitch;
 		}
 
 		static int ReadBc7Mode(ref BitStream bstream)
 		{
-			int i = 0;
-			while (i < 8 && bstream.ReadBit() == 0)
-			{
-				i++;
-			}
-			return i;
+			// Read bits until we find a non-zero bit, up to 8 bits.
+			// The mode is the number of bits read.
+			uint eightBits = bstream.PeakBits(8);
+			int zeros = BitOperations.TrailingZeroCount(eightBits);
+			int bitCount = zeros >= 8 ? 8 : zeros + 1;
+			bstream.Advance(bitCount);
+			return int.Min(zeros, 8);
 		}
 	}
 
@@ -949,6 +958,11 @@ internal static class BcHelpers
 		return (val << (32 - bits)) >> (32 - bits);
 	}
 
+	private static uint ExtendSign(uint val, int bits)
+	{
+		return ExtendSign(val.ToSigned(), bits).ToUnsigned();
+	}
+
 	public static int TransformInverse(int val, int a0, int bits, bool isSigned)
 	{
 		// If the precision of A0 is "p" bits, then the transform algorithm is:
@@ -961,6 +975,11 @@ internal static class BcHelpers
 		return val;
 	}
 
+	private static uint TransformInverse(uint val, uint a0, int bits, bool isSigned)
+	{
+		return TransformInverse(val.ToSigned(), a0.ToSigned(), bits, isSigned).ToUnsigned();
+	}
+
 	/// <summary>
 	/// Essentially copy-paste from documentation
 	/// </summary>
@@ -1028,11 +1047,21 @@ internal static class BcHelpers
 		return unq;
 	}
 
+	private static uint Unquantize(uint val, int bits, bool isSigned)
+	{
+		return Unquantize(val.ToSigned(), bits, isSigned).ToUnsigned();
+	}
+
 	public static int Interpolate(int a, int b, ReadOnlySpan<int> weights, int index)
 	{
 		return ((a * (64 - weights[index])) + (b * weights[index]) + 32) >> 6;
 	}
 
+	private static uint Interpolate(uint a, uint b, ReadOnlySpan<int> weights, int index)
+	{
+		return Interpolate(a.ToSigned(), b.ToSigned(), weights, index).ToUnsigned();
+	}
+
 	public static ushort FinishUnquantize(int val, bool isSigned)
 	{
 		if (!isSigned)
@@ -1041,7 +1070,7 @@ internal static class BcHelpers
 		}
 		else
 		{
-			val = (val < 0) ? -(((-val) * 31) >> 5) : (val * 31) >> 5; // scale the magnitude by 31 / 32
+			val = (val < 0) ? (((-val) * 31) >> 5) : (val * 31) >> 5; // scale the magnitude by 31 / 32
 			int s = 0;
 			if (val < 0)
 			{
@@ -1052,8 +1081,30 @@ internal static class BcHelpers
 		}
 	}
 
-	public static void SwapValues(ref int a, ref int b)
+	private static ushort FinishUnquantize(uint val, bool isSigned)
+	{
+		return FinishUnquantize(val.ToSigned(), isSigned);
+	}
+
+	public static void SwapValues(ref uint a, ref uint b)
 	{
 		(a, b) = (b, a);
 	}
+
+	/// <summary>
+	/// This is for copying a decoded block to the output buffer. It handles the pitch and non-4x4 blocks (if necessary).
+	/// </summary>
+	[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
+	public static void CopyBufferToOutput(Span<byte> buffer, Span<byte> output, int width, int height, int w, int h, int blockWidth, int blockHeight, int pixelSize)
+	{
+		int hEnd = Math.Min(h + blockHeight, height);
+		int wEnd = Math.Min(w + blockWidth, width);
+		for (int i = h; i < hEnd; i++)
+		{
+			int outputOffset = ((i * width) + w) * pixelSize;
+			int outputBufferOffset = ((i - h) * blockWidth) * pixelSize;
+			int copyLength = (wEnd - w) * pixelSize;
+			buffer.Slice(outputBufferOffset, copyLength).CopyTo(output.Slice(outputOffset, copyLength));
+		}
+	}
 }

AssetRipper.TextureDecoder/Bc/BitStream.cs

@@ -1,27 +1,59 @@
-namespace AssetRipper.TextureDecoder.Bc;
+using System.Buffers.Binary;
 
-internal struct BitStream
+namespace AssetRipper.TextureDecoder.Bc;
+
+internal ref struct BitStream
 {
-	public ulong low;
-	public ulong high;
-	
-	public int ReadBits(int numBits)
+	private UInt128 value;
+
+	private readonly uint BottomBits
 	{
-		uint mask = (uint)((1 << numBits) - 1);
-		// Read the low N bits
-		uint bits = (uint)(this.low & mask);
-
-		this.low >>= numBits;
-		// Put the low N bits of "high" into the high 64-N bits of "low".
-		this.low |= (this.high & mask) << ((sizeof(ulong) * 8) - numBits);
-		this.high >>= numBits;
-
-		return (int)bits;
+		[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
+		get => unchecked((uint)this.value);
 	}
 
-	public int ReadBit()
+	public BitStream(UInt128 value)
 	{
-		return this.ReadBits(1);
+		this.value = value;
+	}
+
+	public BitStream(ReadOnlySpan<byte> span) : this(BinaryPrimitives.ReadUInt128LittleEndian(span))
+	{
+	}
+
+	public BitStream(ulong low, ulong high)
+	{
+		value = new UInt128(high, low);
+	}
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
+	public readonly uint PeakBits(int numBits)
+	{
+		uint mask = (1u << numBits) - 1u;
+		uint bits = BottomBits & mask;
+		return bits;
+	}
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
+	public void Advance(int numBits)
+	{
+		this.value >>= numBits;
+	}
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
+	public uint ReadBits(int numBits)
+	{
+		uint bits = PeakBits(numBits);
+		Advance(numBits);
+		return bits;
+	}
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
+	public uint ReadBit()
+	{
+		uint result = BottomBits & 1u;
+		Advance(1);
+		return result;
 	}
 
 	/// <summary>
@@ -29,17 +61,11 @@ internal struct BitStream
 	/// </summary>
 	/// <param name="numBits"></param>
 	/// <returns></returns>
-	public int ReadBitsReversed(int numBits)
+	[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
+	public uint ReadBitsReversed(int numBits)
 	{
-		int bits = this.ReadBits(numBits);
+		uint bits = this.ReadBits(numBits);
 		// Reverse the bits.
-		int result = 0;
-		while (numBits-- != 0)
-		{
-			result <<= 1;
-			result |= bits & 1;
-			bits >>= 1;
-		}
-		return result;
+		return bits.ReverseBits() >> (32 - numBits);
 	}
 }

AssetRipper.TextureDecoder/Bc/NumericExtensions.cs

@@ -0,0 +1,24 @@
+namespace AssetRipper.TextureDecoder.Bc;
+
+internal static class NumericExtensions
+{
+	public static uint ReverseBits(this uint n)
+	{
+		n = (n >> 1) & 0x55555555 | (n << 1) & 0xAAAAAAAA;
+		n = (n >> 2) & 0x33333333 | (n << 2) & 0xCCCCCCCC;
+		n = (n >> 4) & 0x0F0F0F0F | (n << 4) & 0xF0F0F0F0;
+		n = (n >> 8) & 0x00FF00FF | (n << 8) & 0xFF00FF00;
+		n = (n >> 16) & 0x0000FFFF | (n << 16) & 0xFFFF0000;
+		return n;
+	}
+
+	public static uint ToUnsigned(this int value)
+	{
+		return unchecked((uint)value);
+	}
+
+	public static int ToSigned(this uint value)
+	{
+		return unchecked((int)value);
+	}
+}

AssetRipper.TextureDecoder/Dxt/DxtDecoder.cs

@@ -64,6 +64,7 @@ namespace AssetRipper.TextureDecoder.Dxt
 			where TOutputChannelValue : unmanaged
 			where TOutputColor : unmanaged, IColor<TOutputChannelValue>
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			return DecompressDXT1<TOutputColor, TOutputChannelValue>(input, width, height, MemoryMarshal.Cast<byte, TOutputColor>(output));
 		}
 
@@ -185,6 +186,7 @@ namespace AssetRipper.TextureDecoder.Dxt
 			where TOutputChannelValue : unmanaged
 			where TOutputColor : unmanaged, IColor<TOutputChannelValue>
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			return DecompressDXT3<TOutputColor, TOutputChannelValue>(input, width, height, MemoryMarshal.Cast<byte, TOutputColor>(output));
 		}
 
@@ -316,6 +318,7 @@ namespace AssetRipper.TextureDecoder.Dxt
 			where TOutputChannelValue : unmanaged
 			where TOutputColor : unmanaged, IColor<TOutputChannelValue>
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			return DecompressDXT5<TOutputColor, TOutputChannelValue>(input, width, height, MemoryMarshal.Cast<byte, TOutputColor>(output));
 		}
 

AssetRipper.TextureDecoder/Etc/EtcDecoder.cs

@@ -10,6 +10,7 @@ namespace AssetRipper.TextureDecoder.Etc
 
 		public static int DecompressETC(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			int requiredLength = ((width + 3) / 4) * ((height + 3) / 4) * 8;
 			if (input.Length < requiredLength)
 			{
@@ -50,6 +51,7 @@ namespace AssetRipper.TextureDecoder.Etc
 
 		public static int DecompressETC2(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			int requiredLength = ((width + 3) / 4) * ((height + 3) / 4) * 8;
 			if (input.Length < requiredLength)
 			{
@@ -90,6 +92,7 @@ namespace AssetRipper.TextureDecoder.Etc
 
 		public static int DecompressETC2A1(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			int requiredLength = ((width + 3) / 4) * ((height + 3) / 4) * 8;
 			if (input.Length < requiredLength)
 			{
@@ -130,6 +133,7 @@ namespace AssetRipper.TextureDecoder.Etc
 
 		public static int DecompressETC2A8(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			int requiredLength = ((width + 3) / 4) * ((height + 3) / 4) * 16;
 			if (input.Length < requiredLength)
 			{
@@ -171,6 +175,7 @@ namespace AssetRipper.TextureDecoder.Etc
 
 		public static int DecompressEACRUnsigned(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			int requiredLength = ((width + 3) / 4) * ((height + 3) / 4) * 8;
 			if (input.Length < requiredLength)
 			{
@@ -215,6 +220,7 @@ namespace AssetRipper.TextureDecoder.Etc
 
 		public static int DecompressEACRSigned(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			int requiredLength = ((width + 3) / 4) * ((height + 3) / 4) * 8;
 			if (input.Length < requiredLength)
 			{
@@ -259,6 +265,7 @@ namespace AssetRipper.TextureDecoder.Etc
 
 		public static int DecompressEACRGUnsigned(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			int bcw = (width + 3) / 4;
 			int bch = (height + 3) / 4;
 			
@@ -304,6 +311,7 @@ namespace AssetRipper.TextureDecoder.Etc
 
 		public static int DecompressEACRGSigned(ReadOnlySpan<byte> input, int width, int height, Span<byte> output)
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			int requiredLength = ((width + 3) / 4) * ((height + 3) / 4) * 16;
 			if (input.Length < requiredLength)
 			{
@@ -741,6 +749,7 @@ namespace AssetRipper.TextureDecoder.Etc
 
 		private static void DecodeEtc2a8Block(ReadOnlySpan<byte> input, Span<uint> output)
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			int @base = input[0];
 			int data1 = input[1];
 			int mul = data1 >> 4;
@@ -761,6 +770,7 @@ namespace AssetRipper.TextureDecoder.Etc
 
 		private static void DecodeEacUnsignedBlock(ReadOnlySpan<byte> input, Span<uint> output, int channel)
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			int @base = input[0];
 			int data1 = input[1];
 			int mul = data1 >> 4;
@@ -778,6 +788,7 @@ namespace AssetRipper.TextureDecoder.Etc
 
 		private static void DecodeEacSignedBlock(ReadOnlySpan<byte> input, Span<uint> output, int channel)
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			int @base = 127 + unchecked((sbyte)input[0]);
 			int data1 = input[1];
 			int mul = data1 >> 4;
@@ -805,7 +816,7 @@ namespace AssetRipper.TextureDecoder.Etc
 		[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
 		private static void DecodeEac11Block(Span<byte> output, int @base, int ti, int mul, ulong l)
 		{
-			ReadOnlySpan<sbyte> table = Etc2AlphaModTable.AsSpan(ti * 8, 8);
+			ReadOnlySpan<sbyte> table = Etc2AlphaModTable.Slice(ti * 8, 8);
 			for (int i = 0; i < 16; i++, l >>= 3)
 			{
 				int val = @base + mul * table[unchecked((int)(l & 0b111))];
@@ -849,14 +860,14 @@ namespace AssetRipper.TextureDecoder.Etc
 			return data[7] | (uint)data[6] << 8 | (uint)data[5] << 16 | (uint)data[4] << 24 | (ulong)data[3] << 32 | (ulong)data[2] << 40;
 		}
 
-		private static readonly byte[] WriteOrderTable = [0, 4, 8, 12, 1, 5, 9, 13, 2, 6, 10, 14, 3, 7, 11, 15];
-		private static readonly byte[] WriteOrderTableRev = [15, 11, 7, 3, 14, 10, 6, 2, 13, 9, 5, 1, 12, 8, 4, 0];
-		private static readonly int[] Etc1SubblockTable =
+		private static ReadOnlySpan<byte> WriteOrderTable => [0, 4, 8, 12, 1, 5, 9, 13, 2, 6, 10, 14, 3, 7, 11, 15];
+		private static ReadOnlySpan<byte> WriteOrderTableRev => [15, 11, 7, 3, 14, 10, 6, 2, 13, 9, 5, 1, 12, 8, 4, 0];
+		private static ReadOnlySpan<int> Etc1SubblockTable =>
 		[
 			0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1,
 			0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1,
 		];
-		private static readonly int[] Etc1ModifierTable =
+		private static ReadOnlySpan<int> Etc1ModifierTable =>
 		[
 			2, 8, -2, -8,
 			5, 17, -5, -17,
@@ -867,7 +878,7 @@ namespace AssetRipper.TextureDecoder.Etc
 			33, 106, -33, -106,
 			47, 183, -47, -183,
 		];
-		private static readonly int[] PunchthroughModifierTable =
+		private static ReadOnlySpan<int> PunchthroughModifierTable =>
 		[
 			0, 8, 0, -8,
 			0, 17, 0, -17,
@@ -878,8 +889,8 @@ namespace AssetRipper.TextureDecoder.Etc
 			0, 106, 0, -106,
 			0, 183, 0, -183,
 		];
-		private static readonly byte[] Etc2DistanceTable = [3, 6, 11, 16, 23, 32, 41, 64];
-		private static readonly sbyte[] Etc2AlphaModTable =
+		private static ReadOnlySpan<byte> Etc2DistanceTable => [3, 6, 11, 16, 23, 32, 41, 64];
+		private static ReadOnlySpan<sbyte> Etc2AlphaModTable =>
 		[
 			-3, -6,  -9, -15, 2, 5, 8, 14,
 			-3, -7, -10, -13, 2, 6, 9, 12,
@@ -898,6 +909,6 @@ namespace AssetRipper.TextureDecoder.Etc
 			-4, -6,  -8,  -9, 3, 5, 7,  8,
 			-3, -5,  -7,  -9, 2, 4, 6,  8,
 		];
-		private static readonly uint[] PunchthroughMaskTable = [0xFFFFFFFF, 0xFFFFFFFF, 0x00000000, 0xFFFFFFFF];
+		private static ReadOnlySpan<uint> PunchthroughMaskTable => [0xFFFFFFFF, 0xFFFFFFFF, 0x00000000, 0xFFFFFFFF];
 	}
 }

AssetRipper.TextureDecoder/Pvrtc/PvrtcDecoder.cs

@@ -33,6 +33,7 @@ namespace AssetRipper.TextureDecoder.Pvrtc
 		[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
 		public static int DecompressPVRTC(ReadOnlySpan<byte> input, int xDim, int yDim, bool do2bitMode, Span<byte> output)
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			int xBlockSize = do2bitMode ? BlockX2bpp : BlockX4bpp;
 			// for MBX don't allow the sizes to get too small
 			int blockXDim = Math.Max(2, xDim / xBlockSize);
@@ -217,36 +218,36 @@ namespace AssetRipper.TextureDecoder.Pvrtc
 			int modVal;
 			if (modulationModes[y * 16 + x] == 0)
 			{
-				modVal = m_repVals0[modulationVals[y * 16 + x]];
+				modVal = RepVals0[modulationVals[y * 16 + x]];
 			}
 			else if (do2bitMode)
 			{
 				// if this is a stored value
 				if (((x ^ y) & 1) == 0)
 				{
-					modVal = m_repVals0[modulationVals[y * 16 + x]];
+					modVal = RepVals0[modulationVals[y * 16 + x]];
 				}
 				// else average from the neighbours if H&V interpolation..
 				else if (modulationModes[y * 16 + x] == 1)
 				{
-					modVal = (m_repVals0[modulationVals[(y - 1) * 16 + x]] + m_repVals0[modulationVals[(y + 1) * 16 + x]] +
-						m_repVals0[modulationVals[y * 16 + x - 1]] + m_repVals0[modulationVals[y * 16 + x + 1]] + 2) / 4;
+					modVal = (RepVals0[modulationVals[(y - 1) * 16 + x]] + RepVals0[modulationVals[(y + 1) * 16 + x]] +
+						RepVals0[modulationVals[y * 16 + x - 1]] + RepVals0[modulationVals[y * 16 + x + 1]] + 2) / 4;
 				}
 				// else if H-Only
 				else if (modulationModes[y * 16 + x] == 2)
 				{
-					modVal = (m_repVals0[modulationVals[y * 16 + x - 1]] + m_repVals0[modulationVals[y * 16 + x + 1]] + 1) / 2;
+					modVal = (RepVals0[modulationVals[y * 16 + x - 1]] + RepVals0[modulationVals[y * 16 + x + 1]] + 1) / 2;
 				}
 				// else it's V-Only
 				else
 				{
-					modVal = (m_repVals0[modulationVals[(y - 1) * 16 + x]] + m_repVals0[modulationVals[(y + 1) * 16 + x]] + 1) / 2;
+					modVal = (RepVals0[modulationVals[(y - 1) * 16 + x]] + RepVals0[modulationVals[(y + 1) * 16 + x]] + 1) / 2;
 				}
 			}
 			// else it's 4BPP and PT encoding
 			else
 			{
-				modVal = m_repVals1[modulationVals[y * 16 + x]];
+				modVal = RepVals1[modulationVals[y * 16 + x]];
 				doPT = modulationVals[y * 16 + x] == PTIndex;
 			}
 
@@ -487,7 +488,7 @@ namespace AssetRipper.TextureDecoder.Pvrtc
 		private const int BlockX2bpp = 8;
 		private const int BlockX4bpp = 4;
 
-		private static readonly int[] m_repVals0 = [0, 3, 5, 8];
-		private static readonly int[] m_repVals1 = [0, 4, 4, 8];
+		private static ReadOnlySpan<int> RepVals0 => [0, 3, 5, 8];
+		private static ReadOnlySpan<int> RepVals1 => [0, 4, 4, 8];
 	}
 }

AssetRipper.TextureDecoder/Rgb/RgbConverter.cs

@@ -503,6 +503,7 @@ namespace AssetRipper.TextureDecoder.Rgb
 			where TDestinationChannel : unmanaged
 			where TDestinationColor : unmanaged, IColor<TDestinationChannel>
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			ReadOnlySpan<TSourceColor> sourceSpan = MemoryMarshal.Cast<byte, TSourceColor>(input).Slice(0, width * height);
 			Span<TDestinationColor> destinationSpan = MemoryMarshal.Cast<byte, TDestinationColor>(output).Slice(0, width * height);
 			Convert<TSourceColor, TSourceChannel, TDestinationColor, TDestinationChannel>(sourceSpan, destinationSpan);

AssetRipper.TextureDecoder/ThrowHelper.cs

@@ -19,5 +19,13 @@
 				throw new InvalidOperationException($"Not enough space. {spaceRequired} is required, but only {spaceAvailable} is available");
 			}
 		}
+
+		internal static void ThrowIfNotLittleEndian()
+		{
+			if (!BitConverter.IsLittleEndian)
+			{
+				throw new PlatformNotSupportedException();
+			}
+		}
 	}
 }

AssetRipper.TextureDecoder/Yuy2/Yuy2Decoder.cs

@@ -63,6 +63,7 @@ namespace AssetRipper.TextureDecoder.Yuy2
 			where TOutputChannelValue : unmanaged
 			where TOutputColor : unmanaged, IColor<TOutputChannelValue>
 		{
+			ThrowHelper.ThrowIfNotLittleEndian();
 			return DecompressYUY2<TOutputColor, TOutputChannelValue>(input, width, height, MemoryMarshal.Cast<byte, TOutputColor>(output));
 		}
 

Directory.Build.props

@@ -1,12 +1,12 @@
 <Project>
 	<PropertyGroup>
-		<TargetFramework>net8.0</TargetFramework>
+		<TargetFramework>net9.0</TargetFramework>
 		<LangVersion>Latest</LangVersion>
 		<Nullable>enable</Nullable>
 		<IsAotCompatible>true</IsAotCompatible>
 		<CheckForOverflowUnderflow>true</CheckForOverflowUnderflow>
 
-		<Version>2.2.0</Version>
+		<Version>2.3.0</Version>
 		<AssemblyVersion>$(Version)</AssemblyVersion>
 		<Copyright>Copyright © ds5678</Copyright>
 		<Authors>ds5678</Authors>