diff options
author | TSR Berry <20988865+TSRBerry@users.noreply.github.com> | 2023-04-08 01:22:00 +0200 |
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committer | Mary <thog@protonmail.com> | 2023-04-27 23:51:14 +0200 |
commit | cee712105850ac3385cd0091a923438167433f9f (patch) | |
tree | 4a5274b21d8b7f938c0d0ce18736d3f2993b11b1 /src/Ryujinx.Graphics.Texture/Astc/AstcDecoder.cs | |
parent | cd124bda587ef09668a971fa1cac1c3f0cfc9f21 (diff) |
Move solution and projects to src
Diffstat (limited to 'src/Ryujinx.Graphics.Texture/Astc/AstcDecoder.cs')
-rw-r--r-- | src/Ryujinx.Graphics.Texture/Astc/AstcDecoder.cs | 1621 |
1 files changed, 1621 insertions, 0 deletions
diff --git a/src/Ryujinx.Graphics.Texture/Astc/AstcDecoder.cs b/src/Ryujinx.Graphics.Texture/Astc/AstcDecoder.cs new file mode 100644 index 00000000..08738583 --- /dev/null +++ b/src/Ryujinx.Graphics.Texture/Astc/AstcDecoder.cs @@ -0,0 +1,1621 @@ +using Ryujinx.Common.Utilities; +using System; +using System.Diagnostics; +using System.Linq; +using System.Runtime.CompilerServices; +using System.Runtime.InteropServices; + +namespace Ryujinx.Graphics.Texture.Astc +{ + // https://github.com/GammaUNC/FasTC/blob/master/ASTCEncoder/src/Decompressor.cpp + public class AstcDecoder + { + private ReadOnlyMemory<byte> InputBuffer { get; } + private Memory<byte> OutputBuffer { get; } + + private int BlockSizeX { get; } + private int BlockSizeY { get; } + + private AstcLevel[] Levels { get; } + + private bool Success { get; set; } + + public int TotalBlockCount { get; } + + public AstcDecoder( + ReadOnlyMemory<byte> inputBuffer, + Memory<byte> outputBuffer, + int blockWidth, + int blockHeight, + int width, + int height, + int depth, + int levels, + int layers) + { + if ((uint)blockWidth > 12) + { + throw new ArgumentOutOfRangeException(nameof(blockWidth)); + } + + if ((uint)blockHeight > 12) + { + throw new ArgumentOutOfRangeException(nameof(blockHeight)); + } + + InputBuffer = inputBuffer; + OutputBuffer = outputBuffer; + + BlockSizeX = blockWidth; + BlockSizeY = blockHeight; + + Levels = new AstcLevel[levels * layers]; + + Success = true; + + TotalBlockCount = 0; + + int currentInputBlock = 0; + int currentOutputOffset = 0; + + for (int i = 0; i < levels; i++) + { + for (int j = 0; j < layers; j++) + { + ref AstcLevel level = ref Levels[i * layers + j]; + + level.ImageSizeX = Math.Max(1, width >> i); + level.ImageSizeY = Math.Max(1, height >> i); + level.ImageSizeZ = Math.Max(1, depth >> i); + + level.BlockCountX = (level.ImageSizeX + blockWidth - 1) / blockWidth; + level.BlockCountY = (level.ImageSizeY + blockHeight - 1) / blockHeight; + + level.StartBlock = currentInputBlock; + level.OutputByteOffset = currentOutputOffset; + + currentInputBlock += level.TotalBlockCount; + currentOutputOffset += level.PixelCount * 4; + } + } + + TotalBlockCount = currentInputBlock; + } + + private struct AstcLevel + { + public int ImageSizeX { get; set; } + public int ImageSizeY { get; set; } + public int ImageSizeZ { get; set; } + + public int BlockCountX { get; set; } + public int BlockCountY { get; set; } + + public int StartBlock { get; set; } + public int OutputByteOffset { get; set; } + + public int TotalBlockCount => BlockCountX * BlockCountY * ImageSizeZ; + public int PixelCount => ImageSizeX * ImageSizeY * ImageSizeZ; + } + + public static int QueryDecompressedSize(int sizeX, int sizeY, int sizeZ, int levelCount, int layerCount) + { + int size = 0; + + for (int i = 0; i < levelCount; i++) + { + int levelSizeX = Math.Max(1, sizeX >> i); + int levelSizeY = Math.Max(1, sizeY >> i); + int levelSizeZ = Math.Max(1, sizeZ >> i); + + size += levelSizeX * levelSizeY * levelSizeZ * layerCount; + } + + return size * 4; + } + + public void ProcessBlock(int index) + { + Buffer16 inputBlock = MemoryMarshal.Cast<byte, Buffer16>(InputBuffer.Span)[index]; + + Span<int> decompressedData = stackalloc int[144]; + + try + { + DecompressBlock(inputBlock, decompressedData, BlockSizeX, BlockSizeY); + } + catch (Exception) + { + Success = false; + } + + Span<byte> decompressedBytes = MemoryMarshal.Cast<int, byte>(decompressedData); + + AstcLevel levelInfo = GetLevelInfo(index); + + WriteDecompressedBlock(decompressedBytes, OutputBuffer.Span.Slice(levelInfo.OutputByteOffset), + index - levelInfo.StartBlock, levelInfo); + } + + private AstcLevel GetLevelInfo(int blockIndex) + { + foreach (AstcLevel levelInfo in Levels) + { + if (blockIndex < levelInfo.StartBlock + levelInfo.TotalBlockCount) + { + return levelInfo; + } + } + + throw new AstcDecoderException("Invalid block index."); + } + + private void WriteDecompressedBlock(ReadOnlySpan<byte> block, Span<byte> outputBuffer, int blockIndex, AstcLevel level) + { + int stride = level.ImageSizeX * 4; + + int blockCordX = blockIndex % level.BlockCountX; + int blockCordY = blockIndex / level.BlockCountX; + + int pixelCordX = blockCordX * BlockSizeX; + int pixelCordY = blockCordY * BlockSizeY; + + int outputPixelsX = Math.Min(pixelCordX + BlockSizeX, level.ImageSizeX) - pixelCordX; + int outputPixelsY = Math.Min(pixelCordY + BlockSizeY, level.ImageSizeY * level.ImageSizeZ) - pixelCordY; + + int outputStart = pixelCordX * 4 + pixelCordY * stride; + int outputOffset = outputStart; + + int inputOffset = 0; + + for (int i = 0; i < outputPixelsY; i++) + { + ReadOnlySpan<byte> blockRow = block.Slice(inputOffset, outputPixelsX * 4); + Span<byte> outputRow = outputBuffer.Slice(outputOffset); + blockRow.CopyTo(outputRow); + + inputOffset += BlockSizeX * 4; + outputOffset += stride; + } + } + + struct TexelWeightParams + { + public int Width; + public int Height; + public int MaxWeight; + public bool DualPlane; + public bool Error; + public bool VoidExtentLdr; + public bool VoidExtentHdr; + + public int GetPackedBitSize() + { + // How many indices do we have? + int indices = Height * Width; + + if (DualPlane) + { + indices *= 2; + } + + IntegerEncoded intEncoded = IntegerEncoded.CreateEncoding(MaxWeight); + + return intEncoded.GetBitLength(indices); + } + + public int GetNumWeightValues() + { + int ret = Width * Height; + + if (DualPlane) + { + ret *= 2; + } + + return ret; + } + } + + public static bool TryDecodeToRgba8( + ReadOnlyMemory<byte> data, + int blockWidth, + int blockHeight, + int width, + int height, + int depth, + int levels, + int layers, + out Span<byte> decoded) + { + byte[] output = new byte[QueryDecompressedSize(width, height, depth, levels, layers)]; + + AstcDecoder decoder = new AstcDecoder(data, output, blockWidth, blockHeight, width, height, depth, levels, layers); + + for (int i = 0; i < decoder.TotalBlockCount; i++) + { + decoder.ProcessBlock(i); + } + + decoded = output; + + return decoder.Success; + } + + public static bool TryDecodeToRgba8( + ReadOnlyMemory<byte> data, + Memory<byte> outputBuffer, + int blockWidth, + int blockHeight, + int width, + int height, + int depth, + int levels, + int layers) + { + AstcDecoder decoder = new AstcDecoder(data, outputBuffer, blockWidth, blockHeight, width, height, depth, levels, layers); + + for (int i = 0; i < decoder.TotalBlockCount; i++) + { + decoder.ProcessBlock(i); + } + + return decoder.Success; + } + + public static bool TryDecodeToRgba8P( + ReadOnlyMemory<byte> data, + Memory<byte> outputBuffer, + int blockWidth, + int blockHeight, + int width, + int height, + int depth, + int levels, + int layers) + { + AstcDecoder decoder = new AstcDecoder(data, outputBuffer, blockWidth, blockHeight, width, height, depth, levels, layers); + + // Lazy parallelism + Enumerable.Range(0, decoder.TotalBlockCount).AsParallel().ForAll(x => decoder.ProcessBlock(x)); + + return decoder.Success; + } + + public static bool TryDecodeToRgba8P( + ReadOnlyMemory<byte> data, + int blockWidth, + int blockHeight, + int width, + int height, + int depth, + int levels, + int layers, + out byte[] decoded) + { + byte[] output = new byte[QueryDecompressedSize(width, height, depth, levels, layers)]; + + AstcDecoder decoder = new AstcDecoder(data, output, blockWidth, blockHeight, width, height, depth, levels, layers); + + Enumerable.Range(0, decoder.TotalBlockCount).AsParallel().ForAll(x => decoder.ProcessBlock(x)); + + decoded = output; + + return decoder.Success; + } + + public static bool DecompressBlock( + Buffer16 inputBlock, + Span<int> outputBuffer, + int blockWidth, + int blockHeight) + { + BitStream128 bitStream = new BitStream128(inputBlock); + + DecodeBlockInfo(ref bitStream, out TexelWeightParams texelParams); + + if (texelParams.Error) + { + throw new AstcDecoderException("Invalid block mode"); + } + + if (texelParams.VoidExtentLdr) + { + FillVoidExtentLdr(ref bitStream, outputBuffer, blockWidth, blockHeight); + + return true; + } + + if (texelParams.VoidExtentHdr) + { + throw new AstcDecoderException("HDR void extent blocks are not supported."); + } + + if (texelParams.Width > blockWidth) + { + throw new AstcDecoderException("Texel weight grid width should be smaller than block width."); + } + + if (texelParams.Height > blockHeight) + { + throw new AstcDecoderException("Texel weight grid height should be smaller than block height."); + } + + // Read num partitions + int numberPartitions = bitStream.ReadBits(2) + 1; + Debug.Assert(numberPartitions <= 4); + + if (numberPartitions == 4 && texelParams.DualPlane) + { + throw new AstcDecoderException("Dual plane mode is incompatible with four partition blocks."); + } + + // Based on the number of partitions, read the color endpoint mode for + // each partition. + + // Determine partitions, partition index, and color endpoint modes + int planeIndices; + int partitionIndex; + + Span<uint> colorEndpointMode = stackalloc uint[4]; + + BitStream128 colorEndpointStream = new BitStream128(); + + // Read extra config data... + uint baseColorEndpointMode = 0; + + if (numberPartitions == 1) + { + colorEndpointMode[0] = (uint)bitStream.ReadBits(4); + partitionIndex = 0; + } + else + { + partitionIndex = bitStream.ReadBits(10); + baseColorEndpointMode = (uint)bitStream.ReadBits(6); + } + + uint baseMode = (baseColorEndpointMode & 3); + + // Remaining bits are color endpoint data... + int numberWeightBits = texelParams.GetPackedBitSize(); + int remainingBits = bitStream.BitsLeft - numberWeightBits; + + // Consider extra bits prior to texel data... + uint extraColorEndpointModeBits = 0; + + if (baseMode != 0) + { + switch (numberPartitions) + { + case 2: extraColorEndpointModeBits += 2; break; + case 3: extraColorEndpointModeBits += 5; break; + case 4: extraColorEndpointModeBits += 8; break; + default: Debug.Assert(false); break; + } + } + + remainingBits -= (int)extraColorEndpointModeBits; + + // Do we have a dual plane situation? + int planeSelectorBits = 0; + + if (texelParams.DualPlane) + { + planeSelectorBits = 2; + } + + remainingBits -= planeSelectorBits; + + // Read color data... + int colorDataBits = remainingBits; + + while (remainingBits > 0) + { + int numberBits = Math.Min(remainingBits, 8); + int bits = bitStream.ReadBits(numberBits); + colorEndpointStream.WriteBits(bits, numberBits); + remainingBits -= 8; + } + + // Read the plane selection bits + planeIndices = bitStream.ReadBits(planeSelectorBits); + + // Read the rest of the CEM + if (baseMode != 0) + { + uint extraColorEndpointMode = (uint)bitStream.ReadBits((int)extraColorEndpointModeBits); + uint tempColorEndpointMode = (extraColorEndpointMode << 6) | baseColorEndpointMode; + tempColorEndpointMode >>= 2; + + Span<bool> c = stackalloc bool[4]; + + for (int i = 0; i < numberPartitions; i++) + { + c[i] = (tempColorEndpointMode & 1) != 0; + tempColorEndpointMode >>= 1; + } + + Span<byte> m = stackalloc byte[4]; + + for (int i = 0; i < numberPartitions; i++) + { + m[i] = (byte)(tempColorEndpointMode & 3); + tempColorEndpointMode >>= 2; + Debug.Assert(m[i] <= 3); + } + + for (int i = 0; i < numberPartitions; i++) + { + colorEndpointMode[i] = baseMode; + if (!(c[i])) colorEndpointMode[i] -= 1; + colorEndpointMode[i] <<= 2; + colorEndpointMode[i] |= m[i]; + } + } + else if (numberPartitions > 1) + { + uint tempColorEndpointMode = baseColorEndpointMode >> 2; + + for (int i = 0; i < numberPartitions; i++) + { + colorEndpointMode[i] = tempColorEndpointMode; + } + } + + // Make sure everything up till here is sane. + for (int i = 0; i < numberPartitions; i++) + { + Debug.Assert(colorEndpointMode[i] < 16); + } + Debug.Assert(bitStream.BitsLeft == texelParams.GetPackedBitSize()); + + // Decode both color data and texel weight data + Span<int> colorValues = stackalloc int[32]; // Four values * two endpoints * four maximum partitions + DecodeColorValues(colorValues, ref colorEndpointStream, colorEndpointMode, numberPartitions, colorDataBits); + + EndPointSet endPoints; + unsafe { _ = &endPoints; } // Skip struct initialization + + int colorValuesPosition = 0; + + for (int i = 0; i < numberPartitions; i++) + { + ComputeEndpoints(endPoints.Get(i), colorValues, colorEndpointMode[i], ref colorValuesPosition); + } + + // Read the texel weight data. + Buffer16 texelWeightData = inputBlock; + + // Reverse everything + for (int i = 0; i < 8; i++) + { + byte a = ReverseByte(texelWeightData[i]); + byte b = ReverseByte(texelWeightData[15 - i]); + + texelWeightData[i] = b; + texelWeightData[15 - i] = a; + } + + // Make sure that higher non-texel bits are set to zero + int clearByteStart = (texelParams.GetPackedBitSize() >> 3) + 1; + texelWeightData[clearByteStart - 1] &= (byte)((1 << (texelParams.GetPackedBitSize() % 8)) - 1); + + int cLen = 16 - clearByteStart; + for (int i = clearByteStart; i < clearByteStart + cLen; i++) texelWeightData[i] = 0; + + IntegerSequence texelWeightValues; + unsafe { _ = &texelWeightValues; } // Skip struct initialization + texelWeightValues.Reset(); + + BitStream128 weightBitStream = new BitStream128(texelWeightData); + + IntegerEncoded.DecodeIntegerSequence(ref texelWeightValues, ref weightBitStream, texelParams.MaxWeight, texelParams.GetNumWeightValues()); + + // Blocks can be at most 12x12, so we can have as many as 144 weights + Weights weights; + unsafe { _ = &weights; } // Skip struct initialization + + UnquantizeTexelWeights(ref weights, ref texelWeightValues, ref texelParams, blockWidth, blockHeight); + + ushort[] table = Bits.Replicate8_16Table; + + // Now that we have endpoints and weights, we can interpolate and generate + // the proper decoding... + for (int j = 0; j < blockHeight; j++) + { + for (int i = 0; i < blockWidth; i++) + { + int partition = Select2dPartition(partitionIndex, i, j, numberPartitions, ((blockHeight * blockWidth) < 32)); + Debug.Assert(partition < numberPartitions); + + AstcPixel pixel = new AstcPixel(); + for (int component = 0; component < 4; component++) + { + int component0 = endPoints.Get(partition)[0].GetComponent(component); + component0 = table[component0]; + int component1 = endPoints.Get(partition)[1].GetComponent(component); + component1 = table[component1]; + + int plane = 0; + + if (texelParams.DualPlane && (((planeIndices + 1) & 3) == component)) + { + plane = 1; + } + + int weight = weights.Get(plane)[j * blockWidth + i]; + int finalComponent = (component0 * (64 - weight) + component1 * weight + 32) / 64; + + if (finalComponent == 65535) + { + pixel.SetComponent(component, 255); + } + else + { + double finalComponentFloat = finalComponent; + pixel.SetComponent(component, (int)(255.0 * (finalComponentFloat / 65536.0) + 0.5)); + } + } + + outputBuffer[j * blockWidth + i] = pixel.Pack(); + } + } + + return true; + } + + // Blocks can be at most 12x12, so we can have as many as 144 weights + [StructLayout(LayoutKind.Sequential, Size = 144 * sizeof(int) * Count)] + private struct Weights + { + private int _start; + + public const int Count = 2; + + public Span<int> this[int index] + { + get + { + if ((uint)index >= Count) + { + throw new ArgumentOutOfRangeException(); + } + + ref int start = ref Unsafe.Add(ref _start, index * 144); + + return MemoryMarshal.CreateSpan(ref start, 144); + } + } + + [MethodImpl(MethodImplOptions.AggressiveInlining)] + public Span<int> Get(int index) + { + ref int start = ref Unsafe.Add(ref _start, index * 144); + + return MemoryMarshal.CreateSpan(ref start, 144); + } + } + + private static int Select2dPartition(int seed, int x, int y, int partitionCount, bool isSmallBlock) + { + return SelectPartition(seed, x, y, 0, partitionCount, isSmallBlock); + } + + private static int SelectPartition(int seed, int x, int y, int z, int partitionCount, bool isSmallBlock) + { + if (partitionCount == 1) + { + return 0; + } + + if (isSmallBlock) + { + x <<= 1; + y <<= 1; + z <<= 1; + } + + seed += (partitionCount - 1) * 1024; + + int rightNum = Hash52((uint)seed); + byte seed01 = (byte)(rightNum & 0xF); + byte seed02 = (byte)((rightNum >> 4) & 0xF); + byte seed03 = (byte)((rightNum >> 8) & 0xF); + byte seed04 = (byte)((rightNum >> 12) & 0xF); + byte seed05 = (byte)((rightNum >> 16) & 0xF); + byte seed06 = (byte)((rightNum >> 20) & 0xF); + byte seed07 = (byte)((rightNum >> 24) & 0xF); + byte seed08 = (byte)((rightNum >> 28) & 0xF); + byte seed09 = (byte)((rightNum >> 18) & 0xF); + byte seed10 = (byte)((rightNum >> 22) & 0xF); + byte seed11 = (byte)((rightNum >> 26) & 0xF); + byte seed12 = (byte)(((rightNum >> 30) | (rightNum << 2)) & 0xF); + + seed01 *= seed01; seed02 *= seed02; + seed03 *= seed03; seed04 *= seed04; + seed05 *= seed05; seed06 *= seed06; + seed07 *= seed07; seed08 *= seed08; + seed09 *= seed09; seed10 *= seed10; + seed11 *= seed11; seed12 *= seed12; + + int seedHash1, seedHash2, seedHash3; + + if ((seed & 1) != 0) + { + seedHash1 = (seed & 2) != 0 ? 4 : 5; + seedHash2 = (partitionCount == 3) ? 6 : 5; + } + else + { + seedHash1 = (partitionCount == 3) ? 6 : 5; + seedHash2 = (seed & 2) != 0 ? 4 : 5; + } + + seedHash3 = (seed & 0x10) != 0 ? seedHash1 : seedHash2; + + seed01 >>= seedHash1; seed02 >>= seedHash2; seed03 >>= seedHash1; seed04 >>= seedHash2; + seed05 >>= seedHash1; seed06 >>= seedHash2; seed07 >>= seedHash1; seed08 >>= seedHash2; + seed09 >>= seedHash3; seed10 >>= seedHash3; seed11 >>= seedHash3; seed12 >>= seedHash3; + + int a = seed01 * x + seed02 * y + seed11 * z + (rightNum >> 14); + int b = seed03 * x + seed04 * y + seed12 * z + (rightNum >> 10); + int c = seed05 * x + seed06 * y + seed09 * z + (rightNum >> 6); + int d = seed07 * x + seed08 * y + seed10 * z + (rightNum >> 2); + + a &= 0x3F; b &= 0x3F; c &= 0x3F; d &= 0x3F; + + if (partitionCount < 4) d = 0; + if (partitionCount < 3) c = 0; + + if (a >= b && a >= c && a >= d) return 0; + else if (b >= c && b >= d) return 1; + else if (c >= d) return 2; + return 3; + } + + static int Hash52(uint val) + { + val ^= val >> 15; val -= val << 17; val += val << 7; val += val << 4; + val ^= val >> 5; val += val << 16; val ^= val >> 7; val ^= val >> 3; + val ^= val << 6; val ^= val >> 17; + + return (int)val; + } + + static void UnquantizeTexelWeights( + ref Weights outputBuffer, + ref IntegerSequence weights, + ref TexelWeightParams texelParams, + int blockWidth, + int blockHeight) + { + int weightIndices = 0; + Weights unquantized; + unsafe { _ = &unquantized; } // Skip struct initialization + + Span<IntegerEncoded> weightsList = weights.List; + Span<int> unquantized0 = unquantized[0]; + Span<int> unquantized1 = unquantized[1]; + + for (int i = 0; i < weightsList.Length; i++) + { + unquantized0[weightIndices] = UnquantizeTexelWeight(weightsList[i]); + + if (texelParams.DualPlane) + { + i++; + unquantized1[weightIndices] = UnquantizeTexelWeight(weightsList[i]); + + if (i == weightsList.Length) + { + break; + } + } + + if (++weightIndices >= texelParams.Width * texelParams.Height) break; + } + + // Do infill if necessary (Section C.2.18) ... + int ds = (1024 + blockWidth / 2) / (blockWidth - 1); + int dt = (1024 + blockHeight / 2) / (blockHeight - 1); + + int planeScale = texelParams.DualPlane ? 2 : 1; + + for (int plane = 0; plane < planeScale; plane++) + { + Span<int> unquantizedSpan = unquantized.Get(plane); + Span<int> outputSpan = outputBuffer.Get(plane); + + for (int t = 0; t < blockHeight; t++) + { + for (int s = 0; s < blockWidth; s++) + { + int cs = ds * s; + int ct = dt * t; + + int gs = (cs * (texelParams.Width - 1) + 32) >> 6; + int gt = (ct * (texelParams.Height - 1) + 32) >> 6; + + int js = gs >> 4; + int fs = gs & 0xF; + + int jt = gt >> 4; + int ft = gt & 0x0F; + + int w11 = (fs * ft + 8) >> 4; + + int v0 = js + jt * texelParams.Width; + + int weight = 8; + + int wxh = texelParams.Width * texelParams.Height; + + if (v0 < wxh) + { + weight += unquantizedSpan[v0] * (16 - fs - ft + w11); + + if (v0 + 1 < wxh) + { + weight += unquantizedSpan[v0 + 1] * (fs - w11); + } + } + + if (v0 + texelParams.Width < wxh) + { + weight += unquantizedSpan[v0 + texelParams.Width] * (ft - w11); + + if (v0 + texelParams.Width + 1 < wxh) + { + weight += unquantizedSpan[v0 + texelParams.Width + 1] * w11; + } + } + + outputSpan[t * blockWidth + s] = weight >> 4; + } + } + } + } + + static int UnquantizeTexelWeight(IntegerEncoded intEncoded) + { + int bitValue = intEncoded.BitValue; + int bitLength = intEncoded.NumberBits; + + int a = Bits.Replicate1_7(bitValue & 1); + int b = 0, c = 0, d = 0; + + int result = 0; + + switch (intEncoded.GetEncoding()) + { + case IntegerEncoded.EIntegerEncoding.JustBits: + result = Bits.Replicate(bitValue, bitLength, 6); + break; + + case IntegerEncoded.EIntegerEncoding.Trit: + { + d = intEncoded.TritValue; + Debug.Assert(d < 3); + + switch (bitLength) + { + case 0: + { + result = d switch + { + 0 => 0, + 1 => 32, + 2 => 63, + _ => 0 + }; + + break; + } + + case 1: + { + c = 50; + break; + } + + case 2: + { + c = 23; + int b2 = (bitValue >> 1) & 1; + b = (b2 << 6) | (b2 << 2) | b2; + + break; + } + + case 3: + { + c = 11; + int cb = (bitValue >> 1) & 3; + b = (cb << 5) | cb; + + break; + } + + default: + throw new AstcDecoderException("Invalid trit encoding for texel weight."); + } + + break; + } + + case IntegerEncoded.EIntegerEncoding.Quint: + { + d = intEncoded.QuintValue; + Debug.Assert(d < 5); + + switch (bitLength) + { + case 0: + { + result = d switch + { + 0 => 0, + 1 => 16, + 2 => 32, + 3 => 47, + 4 => 63, + _ => 0 + }; + + break; + } + + case 1: + { + c = 28; + + break; + } + + case 2: + { + c = 13; + int b2 = (bitValue >> 1) & 1; + b = (b2 << 6) | (b2 << 1); + + break; + } + + default: + throw new AstcDecoderException("Invalid quint encoding for texel weight."); + } + + break; + } + } + + if (intEncoded.GetEncoding() != IntegerEncoded.EIntegerEncoding.JustBits && bitLength > 0) + { + // Decode the value... + result = d * c + b; + result ^= a; + result = (a & 0x20) | (result >> 2); + } + + Debug.Assert(result < 64); + + // Change from [0,63] to [0,64] + if (result > 32) + { + result += 1; + } + + return result; + } + + static byte ReverseByte(byte b) + { + // Taken from http://graphics.stanford.edu/~seander/bithacks.html#ReverseByteWith64Bits + return (byte)((((b) * 0x80200802L) & 0x0884422110L) * 0x0101010101L >> 32); + } + + static Span<uint> ReadUintColorValues(int number, Span<int> colorValues, ref int colorValuesPosition) + { + Span<int> ret = colorValues.Slice(colorValuesPosition, number); + + colorValuesPosition += number; + + return MemoryMarshal.Cast<int, uint>(ret); + } + + static Span<int> ReadIntColorValues(int number, Span<int> colorValues, ref int colorValuesPosition) + { + Span<int> ret = colorValues.Slice(colorValuesPosition, number); + + colorValuesPosition += number; + + return ret; + } + + static void ComputeEndpoints( + Span<AstcPixel> endPoints, + Span<int> colorValues, + uint colorEndpointMode, + ref int colorValuesPosition) + { + switch (colorEndpointMode) + { + case 0: + { + Span<uint> val = ReadUintColorValues(2, colorValues, ref colorValuesPosition); + + endPoints[0] = new AstcPixel(0xFF, (short)val[0], (short)val[0], (short)val[0]); + endPoints[1] = new AstcPixel(0xFF, (short)val[1], (short)val[1], (short)val[1]); + + break; + } + + + case 1: + { + Span<uint> val = ReadUintColorValues(2, colorValues, ref colorValuesPosition); + int l0 = (int)((val[0] >> 2) | (val[1] & 0xC0)); + int l1 = (int)Math.Max(l0 + (val[1] & 0x3F), 0xFFU); + + endPoints[0] = new AstcPixel(0xFF, (short)l0, (short)l0, (short)l0); + endPoints[1] = new AstcPixel(0xFF, (short)l1, (short)l1, (short)l1); + + break; + } + + case 4: + { + Span<uint> val = ReadUintColorValues(4, colorValues, ref colorValuesPosition); + + endPoints[0] = new AstcPixel((short)val[2], (short)val[0], (short)val[0], (short)val[0]); + endPoints[1] = new AstcPixel((short)val[3], (short)val[1], (short)val[1], (short)val[1]); + + break; + } + + case 5: + { + Span<int> val = ReadIntColorValues(4, colorValues, ref colorValuesPosition); + + Bits.BitTransferSigned(ref val[1], ref val[0]); + Bits.BitTransferSigned(ref val[3], ref val[2]); + + endPoints[0] = new AstcPixel((short)val[2], (short)val[0], (short)val[0], (short)val[0]); + endPoints[1] = new AstcPixel((short)(val[2] + val[3]), (short)(val[0] + val[1]), (short)(val[0] + val[1]), (short)(val[0] + val[1])); + + endPoints[0].ClampByte(); + endPoints[1].ClampByte(); + + break; + } + + case 6: + { + Span<uint> val = ReadUintColorValues(4, colorValues, ref colorValuesPosition); + + endPoints[0] = new AstcPixel(0xFF, (short)(val[0] * val[3] >> 8), (short)(val[1] * val[3] >> 8), (short)(val[2] * val[3] >> 8)); + endPoints[1] = new AstcPixel(0xFF, (short)val[0], (short)val[1], (short)val[2]); + + break; + } + + case 8: + { + Span<uint> val = ReadUintColorValues(6, colorValues, ref colorValuesPosition); + + if (val[1] + val[3] + val[5] >= val[0] + val[2] + val[4]) + { + endPoints[0] = new AstcPixel(0xFF, (short)val[0], (short)val[2], (short)val[4]); + endPoints[1] = new AstcPixel(0xFF, (short)val[1], (short)val[3], (short)val[5]); + } + else + { + endPoints[0] = AstcPixel.BlueContract(0xFF, (short)val[1], (short)val[3], (short)val[5]); + endPoints[1] = AstcPixel.BlueContract(0xFF, (short)val[0], (short)val[2], (short)val[4]); + } + + break; + } + + case 9: + { + Span<int> val = ReadIntColorValues(6, colorValues, ref colorValuesPosition); + + Bits.BitTransferSigned(ref val[1], ref val[0]); + Bits.BitTransferSigned(ref val[3], ref val[2]); + Bits.BitTransferSigned(ref val[5], ref val[4]); + + if (val[1] + val[3] + val[5] >= 0) + { + endPoints[0] = new AstcPixel(0xFF, (short)val[0], (short)val[2], (short)val[4]); + endPoints[1] = new AstcPixel(0xFF, (short)(val[0] + val[1]), (short)(val[2] + val[3]), (short)(val[4] + val[5])); + } + else + { + endPoints[0] = AstcPixel.BlueContract(0xFF, val[0] + val[1], val[2] + val[3], val[4] + val[5]); + endPoints[1] = AstcPixel.BlueContract(0xFF, val[0], val[2], val[4]); + } + + endPoints[0].ClampByte(); + endPoints[1].ClampByte(); + + break; + } + + case 10: + { + Span<uint> val = ReadUintColorValues(6, colorValues, ref colorValuesPosition); + + endPoints[0] = new AstcPixel((short)val[4], (short)(val[0] * val[3] >> 8), (short)(val[1] * val[3] >> 8), (short)(val[2] * val[3] >> 8)); + endPoints[1] = new AstcPixel((short)val[5], (short)val[0], (short)val[1], (short)val[2]); + + break; + } + + case 12: + { + Span<uint> val = ReadUintColorValues(8, colorValues, ref colorValuesPosition); + + if (val[1] + val[3] + val[5] >= val[0] + val[2] + val[4]) + { + endPoints[0] = new AstcPixel((short)val[6], (short)val[0], (short)val[2], (short)val[4]); + endPoints[1] = new AstcPixel((short)val[7], (short)val[1], (short)val[3], (short)val[5]); + } + else + { + endPoints[0] = AstcPixel.BlueContract((short)val[7], (short)val[1], (short)val[3], (short)val[5]); + endPoints[1] = AstcPixel.BlueContract((short)val[6], (short)val[0], (short)val[2], (short)val[4]); + } + + break; + } + + case 13: + { + Span<int> val = ReadIntColorValues(8, colorValues, ref colorValuesPosition); + + Bits.BitTransferSigned(ref val[1], ref val[0]); + Bits.BitTransferSigned(ref val[3], ref val[2]); + Bits.BitTransferSigned(ref val[5], ref val[4]); + Bits.BitTransferSigned(ref val[7], ref val[6]); + + if (val[1] + val[3] + val[5] >= 0) + { + endPoints[0] = new AstcPixel((short)val[6], (short)val[0], (short)val[2], (short)val[4]); + endPoints[1] = new AstcPixel((short)(val[7] + val[6]), (short)(val[0] + val[1]), (short)(val[2] + val[3]), (short)(val[4] + val[5])); + } + else + { + endPoints[0] = AstcPixel.BlueContract(val[6] + val[7], val[0] + val[1], val[2] + val[3], val[4] + val[5]); + endPoints[1] = AstcPixel.BlueContract(val[6], val[0], val[2], val[4]); + } + + endPoints[0].ClampByte(); + endPoints[1].ClampByte(); + + break; + } + + default: + throw new AstcDecoderException("Unsupported color endpoint mode (is it HDR?)"); + } + } + + static void DecodeColorValues( + Span<int> outputValues, + ref BitStream128 colorBitStream, + Span<uint> modes, + int numberPartitions, + int numberBitsForColorData) + { + // First figure out how many color values we have + int numberValues = 0; + + for (int i = 0; i < numberPartitions; i++) + { + numberValues += (int)((modes[i] >> 2) + 1) << 1; + } + + // Then based on the number of values and the remaining number of bits, + // figure out the max value for each of them... + int range = 256; + + while (--range > 0) + { + IntegerEncoded intEncoded = IntegerEncoded.CreateEncoding(range); + int bitLength = intEncoded.GetBitLength(numberValues); + + if (bitLength <= numberBitsForColorData) + { + // Find the smallest possible range that matches the given encoding + while (--range > 0) + { + IntegerEncoded newIntEncoded = IntegerEncoded.CreateEncoding(range); + if (!newIntEncoded.MatchesEncoding(intEncoded)) + { + break; + } + } + + // Return to last matching range. + range++; + break; + } + } + + // We now have enough to decode our integer sequence. + IntegerSequence integerEncodedSequence; + unsafe { _ = &integerEncodedSequence; } // Skip struct initialization + integerEncodedSequence.Reset(); + + IntegerEncoded.DecodeIntegerSequence(ref integerEncodedSequence, ref colorBitStream, range, numberValues); + + // Once we have the decoded values, we need to dequantize them to the 0-255 range + // This procedure is outlined in ASTC spec C.2.13 + int outputIndices = 0; + + foreach (ref IntegerEncoded intEncoded in integerEncodedSequence.List) + { + int bitLength = intEncoded.NumberBits; + int bitValue = intEncoded.BitValue; + + Debug.Assert(bitLength >= 1); + + int a = 0, b = 0, c = 0, d = 0; + // A is just the lsb replicated 9 times. + a = Bits.Replicate(bitValue & 1, 1, 9); + + switch (intEncoded.GetEncoding()) + { + case IntegerEncoded.EIntegerEncoding.JustBits: + { + outputValues[outputIndices++] = Bits.Replicate(bitValue, bitLength, 8); + + break; + } + + case IntegerEncoded.EIntegerEncoding.Trit: + { + d = intEncoded.TritValue; + + switch (bitLength) + { + case 1: + { + c = 204; + + break; + } + + case 2: + { + c = 93; + // B = b000b0bb0 + int b2 = (bitValue >> 1) & 1; + b = (b2 << 8) | (b2 << 4) | (b2 << 2) | (b2 << 1); + + break; + } + + case 3: + { + c = 44; + // B = cb000cbcb + int cb = (bitValue >> 1) & 3; + b = (cb << 7) | (cb << 2) | cb; + + break; + } + + + case 4: + { + c = 22; + // B = dcb000dcb + int dcb = (bitValue >> 1) & 7; + b = (dcb << 6) | dcb; + + break; + } + + case 5: + { + c = 11; + // B = edcb000ed + int edcb = (bitValue >> 1) & 0xF; + b = (edcb << 5) | (edcb >> 2); + + break; + } + + case 6: + { + c = 5; + // B = fedcb000f + int fedcb = (bitValue >> 1) & 0x1F; + b = (fedcb << 4) | (fedcb >> 4); + + break; + } + + default: + throw new AstcDecoderException("Unsupported trit encoding for color values."); + } + + break; + } + + case IntegerEncoded.EIntegerEncoding.Quint: + { + d = intEncoded.QuintValue; + + switch (bitLength) + { + case 1: + { + c = 113; + + break; + } + + case 2: + { + c = 54; + // B = b0000bb00 + int b2 = (bitValue >> 1) & 1; + b = (b2 << 8) | (b2 << 3) | (b2 << 2); + + break; + } + + case 3: + { + c = 26; + // B = cb0000cbc + int cb = (bitValue >> 1) & 3; + b = (cb << 7) | (cb << 1) | (cb >> 1); + + break; + } + + case 4: + { + c = 13; + // B = dcb0000dc + int dcb = (bitValue >> 1) & 7; + b = (dcb << 6) | (dcb >> 1); + + break; + } + + case 5: + { + c = 6; + // B = edcb0000e + int edcb = (bitValue >> 1) & 0xF; + b = (edcb << 5) | (edcb >> 3); + + break; + } + + default: + throw new AstcDecoderException("Unsupported quint encoding for color values."); + } + break; + } + } + + if (intEncoded.GetEncoding() != IntegerEncoded.EIntegerEncoding.JustBits) + { + int T = d * c + b; + T ^= a; + T = (a & 0x80) | (T >> 2); + + outputValues[outputIndices++] = T; + } + } + + // Make sure that each of our values is in the proper range... + for (int i = 0; i < numberValues; i++) + { + Debug.Assert(outputValues[i] <= 255); + } + } + + static void FillVoidExtentLdr(ref BitStream128 bitStream, Span<int> outputBuffer, int blockWidth, int blockHeight) + { + // Don't actually care about the void extent, just read the bits... + for (int i = 0; i < 4; ++i) + { + bitStream.ReadBits(13); + } + + // Decode the RGBA components and renormalize them to the range [0, 255] + ushort r = (ushort)bitStream.ReadBits(16); + ushort g = (ushort)bitStream.ReadBits(16); + ushort b = (ushort)bitStream.ReadBits(16); + ushort a = (ushort)bitStream.ReadBits(16); + + int rgba = (r >> 8) | (g & 0xFF00) | ((b) & 0xFF00) << 8 | ((a) & 0xFF00) << 16; + + for (int j = 0; j < blockHeight; j++) + { + for (int i = 0; i < blockWidth; i++) + { + outputBuffer[j * blockWidth + i] = rgba; + } + } + } + + static void DecodeBlockInfo(ref BitStream128 bitStream, out TexelWeightParams texelParams) + { + texelParams = new TexelWeightParams(); + + // Read the entire block mode all at once + ushort modeBits = (ushort)bitStream.ReadBits(11); + + // Does this match the void extent block mode? + if ((modeBits & 0x01FF) == 0x1FC) + { + if ((modeBits & 0x200) != 0) + { + texelParams.VoidExtentHdr = true; + } + else + { + texelParams.VoidExtentLdr = true; + } + + // Next two bits must be one. + if ((modeBits & 0x400) == 0 || bitStream.ReadBits(1) == 0) + { + texelParams.Error = true; + } + + return; + } + + // First check if the last four bits are zero + if ((modeBits & 0xF) == 0) + { + texelParams.Error = true; + + return; + } + + // If the last two bits are zero, then if bits + // [6-8] are all ones, this is also reserved. + if ((modeBits & 0x3) == 0 && (modeBits & 0x1C0) == 0x1C0) + { + texelParams.Error = true; + + return; + } + + // Otherwise, there is no error... Figure out the layout + // of the block mode. Layout is determined by a number + // between 0 and 9 corresponding to table C.2.8 of the + // ASTC spec. + int layout; + + if ((modeBits & 0x1) != 0 || (modeBits & 0x2) != 0) + { + // layout is in [0-4] + if ((modeBits & 0x8) != 0) + { + // layout is in [2-4] + if ((modeBits & 0x4) != 0) + { + // layout is in [3-4] + if ((modeBits & 0x100) != 0) + { + layout = 4; + } + else + { + layout = 3; + } + } + else + { + layout = 2; + } + } + else + { + // layout is in [0-1] + if ((modeBits & 0x4) != 0) + { + layout = 1; + } + else + { + layout = 0; + } + } + } + else + { + // layout is in [5-9] + if ((modeBits & 0x100) != 0) + { + // layout is in [7-9] + if ((modeBits & 0x80) != 0) + { + // layout is in [7-8] + Debug.Assert((modeBits & 0x40) == 0); + + if ((modeBits & 0x20) != 0) + { + layout = 8; + } + else + { + layout = 7; + } + } + else + { + layout = 9; + } + } + else + { + // layout is in [5-6] + if ((modeBits & 0x80) != 0) + { + layout = 6; + } + else + { + layout = 5; + } + } + } + + Debug.Assert(layout < 10); + + // Determine R + int r = (modeBits >> 4) & 1; + if (layout < 5) + { + r |= (modeBits & 0x3) << 1; + } + else + { + r |= (modeBits & 0xC) >> 1; + } + + Debug.Assert(2 <= r && r <= 7); + + // Determine width & height + switch (layout) + { + case 0: + { + int a = (modeBits >> 5) & 0x3; + int b = (modeBits >> 7) & 0x3; + + texelParams.Width = b + 4; + texelParams.Height = a + 2; + + break; + } + + case 1: + { + int a = (modeBits >> 5) & 0x3; + int b = (modeBits >> 7) & 0x3; + + texelParams.Width = b + 8; + texelParams.Height = a + 2; + + break; + } + + case 2: + { + int a = (modeBits >> 5) & 0x3; + int b = (modeBits >> 7) & 0x3; + + texelParams.Width = a + 2; + texelParams.Height = b + 8; + + break; + } + + case 3: + { + int a = (modeBits >> 5) & 0x3; + int b = (modeBits >> 7) & 0x1; + + texelParams.Width = a + 2; + texelParams.Height = b + 6; + + break; + } + + case 4: + { + int a = (modeBits >> 5) & 0x3; + int b = (modeBits >> 7) & 0x1; + + texelParams.Width = b + 2; + texelParams.Height = a + 2; + + break; + } + + case 5: + { + int a = (modeBits >> 5) & 0x3; + + texelParams.Width = 12; + texelParams.Height = a + 2; + + break; + } + + case 6: + { + int a = (modeBits >> 5) & 0x3; + + texelParams.Width = a + 2; + texelParams.Height = 12; + + break; + } + + case 7: + { + texelParams.Width = 6; + texelParams.Height = 10; + + break; + } + + case 8: + { + texelParams.Width = 10; + texelParams.Height = 6; + break; + } + + case 9: + { + int a = (modeBits >> 5) & 0x3; + int b = (modeBits >> 9) & 0x3; + + texelParams.Width = a + 6; + texelParams.Height = b + 6; + + break; + } + + default: + // Don't know this layout... + texelParams.Error = true; + break; + } + + // Determine whether or not we're using dual planes + // and/or high precision layouts. + bool d = ((layout != 9) && ((modeBits & 0x400) != 0)); + bool h = (layout != 9) && ((modeBits & 0x200) != 0); + + if (h) + { + ReadOnlySpan<byte> maxWeights = new byte[] { 9, 11, 15, 19, 23, 31 }; + texelParams.MaxWeight = maxWeights[r - 2]; + } + else + { + ReadOnlySpan<byte> maxWeights = new byte[] { 1, 2, 3, 4, 5, 7 }; + texelParams.MaxWeight = maxWeights[r - 2]; + } + + texelParams.DualPlane = d; + } + } +} |