Ryujinx/Ryujinx.Graphics/Gal/Texture/ASTCDecoder.cs
Ac_K aeb1bbf50c Add an ASTC Decoder (Not currently used in Ryujinx) (#131)
* Add an ASTC Decoder (Not currently used in Ryujinx)

* Update ASTCDecoder.cs
2018-06-01 15:00:16 -03:00

1384 lines
49 KiB
C#

using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
namespace Ryujinx.Graphics.Gal.Texture
{
public class ASTCDecoderException : Exception
{
public ASTCDecoderException(string ExMsg) : base(ExMsg) { }
}
//https://github.com/GammaUNC/FasTC/blob/master/ASTCEncoder/src/Decompressor.cpp
public static class ASTCDecoder
{
struct TexelWeightParams
{
public int Width;
public int Height;
public bool DualPlane;
public int MaxWeight;
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 byte[] DecodeToRGBA8888(
byte[] InputBuffer,
int BlockX,
int BlockY,
int BlockZ,
int X,
int Y,
int Z)
{
using (MemoryStream InputStream = new MemoryStream(InputBuffer))
{
BinaryReader BinReader = new BinaryReader(InputStream);
if (BlockX > 12 || BlockY > 12)
{
throw new ASTCDecoderException("Block size unsupported!");
}
if (BlockZ != 1 || Z != 1)
{
throw new ASTCDecoderException("3D compressed textures unsupported!");
}
using (MemoryStream OutputStream = new MemoryStream())
{
int BlockIndex = 0;
for (int j = 0; j < Y; j += BlockY)
{
for (int i = 0; i < X; i += BlockX)
{
int[] DecompressedData = new int[144];
DecompressBlock(BinReader.ReadBytes(0x10), DecompressedData, BlockX, BlockY);
int DecompressedWidth = Math.Min(BlockX, X - i);
int DecompressedHeight = Math.Min(BlockY, Y - j);
int BaseOffsets = (j * X + i) * 4;
for (int jj = 0; jj < DecompressedHeight; jj++)
{
OutputStream.Seek(BaseOffsets + jj * X * 4, SeekOrigin.Begin);
byte[] OutputBuffer = new byte[DecompressedData.Length * sizeof(int)];
Buffer.BlockCopy(DecompressedData, 0, OutputBuffer, 0, OutputBuffer.Length);
OutputStream.Write(OutputBuffer, jj * BlockX * 4, DecompressedWidth * 4);
}
BlockIndex++;
}
}
return OutputStream.ToArray();
}
}
}
public static bool DecompressBlock(
byte[] InputBuffer,
int[] OutputBuffer,
int BlockWidth,
int BlockHeight)
{
BitArrayStream BitStream = new BitArrayStream(new BitArray(InputBuffer));
TexelWeightParams TexelParams = DecodeBlockInfo(BitStream);
if (TexelParams.Error)
{
throw new ASTCDecoderException("Invalid block mode");
}
if (TexelParams.VoidExtentLDR)
{
FillVoidExtentLDR(BitStream, OutputBuffer, BlockWidth, BlockHeight);
return true;
}
if (TexelParams.VoidExtentHDR)
{
throw new ASTCDecoderException("HDR void extent blocks are unsupported!");
}
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 = -1;
int PartitionIndex;
uint[] ColorEndpointMode = { 0, 0, 0, 0 };
BitArrayStream ColorEndpointStream = new BitArrayStream(new BitArray(16 * 8));
// 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 = 128 - NumberWeightBits - BitStream.Position;
// 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;
bool[] C = new bool[4];
for (int i = 0; i < NumberPartitions; i++)
{
C[i] = (TempColorEndpointMode & 1) != 0;
TempColorEndpointMode >>= 1;
}
byte[] M = new 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 (uint 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.Position + TexelParams.GetPackedBitSize() == 128);
// Decode both color data and texel weight data
int[] ColorValues = new int[32]; // Four values * two endpoints * four maximum partitions
DecodeColorValues(ColorValues, ColorEndpointStream.ToByteArray(), ColorEndpointMode, NumberPartitions, ColorDataBits);
ASTCPixel[][] EndPoints = new ASTCPixel[4][];
EndPoints[0] = new ASTCPixel[2];
EndPoints[1] = new ASTCPixel[2];
EndPoints[2] = new ASTCPixel[2];
EndPoints[3] = new ASTCPixel[2];
int ColorValuesPosition = 0;
for (int i = 0; i < NumberPartitions; i++)
{
ComputeEndpoints(EndPoints[i], ColorValues, ColorEndpointMode[i], ref ColorValuesPosition);
}
// Read the texel weight data.
byte[] TexelWeightData = (byte[])InputBuffer.Clone();
// 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;
List<IntegerEncoded> TexelWeightValues = new List<IntegerEncoded>();
BitArrayStream WeightBitStream = new BitArrayStream(new BitArray(TexelWeightData));
IntegerEncoded.DecodeIntegerSequence(TexelWeightValues, WeightBitStream, TexelParams.MaxWeight, TexelParams.GetNumWeightValues());
// Blocks can be at most 12x12, so we can have as many as 144 weights
int[][] Weights = new int[2][];
Weights[0] = new int[144];
Weights[1] = new int[144];
UnquantizeTexelWeights(Weights, TexelWeightValues, TexelParams, BlockWidth, BlockHeight);
// 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(0, 0, 0, 0);
for (int Component = 0; Component < 4; Component++)
{
int Component0 = EndPoints[Partition][0].GetComponent(Component);
Component0 = BitArrayStream.Replicate(Component0, 8, 16);
int Component1 = EndPoints[Partition][1].GetComponent(Component);
Component1 = BitArrayStream.Replicate(Component1, 8, 16);
int Plane = 0;
if (TexelParams.DualPlane && (((PlaneIndices + 1) & 3) == Component))
{
Plane = 1;
}
int Weight = Weights[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;
}
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(
int[][] OutputBuffer,
List<IntegerEncoded> Weights,
TexelWeightParams TexelParams,
int BlockWidth,
int BlockHeight)
{
int WeightIndices = 0;
int[][] Unquantized = new int[2][];
Unquantized[0] = new int[144];
Unquantized[1] = new int[144];
for (int i = 0; i < Weights.Count; i++)
{
Unquantized[0][WeightIndices] = UnquantizeTexelWeight(Weights[i]);
if (TexelParams.DualPlane)
{
i++;
Unquantized[1][WeightIndices] = UnquantizeTexelWeight(Weights[i]);
if (i == Weights.Count)
{
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++)
{
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 w10 = ft - w11;
int w01 = fs - w11;
int w00 = 16 - fs - ft + w11;
int v0 = js + jt * TexelParams.Width;
int p00 = 0;
int p01 = 0;
int p10 = 0;
int p11 = 0;
if (v0 < (TexelParams.Width * TexelParams.Height))
{
p00 = Unquantized[Plane][v0];
}
if (v0 + 1 < (TexelParams.Width * TexelParams.Height))
{
p01 = Unquantized[Plane][v0 + 1];
}
if (v0 + TexelParams.Width < (TexelParams.Width * TexelParams.Height))
{
p10 = Unquantized[Plane][v0 + TexelParams.Width];
}
if (v0 + TexelParams.Width + 1 < (TexelParams.Width * TexelParams.Height))
{
p11 = Unquantized[Plane][v0 + TexelParams.Width + 1];
}
OutputBuffer[Plane][t * BlockWidth + s] = (p00 * w00 + p01 * w01 + p10 * w10 + p11 * w11 + 8) >> 4;
}
}
}
}
static int UnquantizeTexelWeight(IntegerEncoded IntEncoded)
{
int BitValue = IntEncoded.BitValue;
int BitLength = IntEncoded.NumberBits;
int A = BitArrayStream.Replicate(BitValue & 1, 1, 7);
int B = 0, C = 0, D = 0;
int Result = 0;
switch (IntEncoded.GetEncoding())
{
case IntegerEncoded.EIntegerEncoding.JustBits:
Result = BitArrayStream.Replicate(BitValue, BitLength, 6);
break;
case IntegerEncoded.EIntegerEncoding.Trit:
{
D = IntEncoded.TritValue;
Debug.Assert(D < 3);
switch (BitLength)
{
case 0:
{
int[] Results = { 0, 32, 63 };
Result = Results[D];
break;
}
case 1:
{
C = 50;
break;
}
case 2:
{
C = 23;
int b = (BitValue >> 1) & 1;
B = (b << 6) | (b << 2) | b;
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:
{
int[] Results = { 0, 16, 32, 47, 63 };
Result = Results[D];
break;
}
case 1:
{
C = 28;
break;
}
case 2:
{
C = 13;
int b = (BitValue >> 1) & 1;
B = (b << 6) | (b << 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 uint[] ReadUintColorValues(int Number, int[] ColorValues, ref int ColorValuesPosition)
{
uint[] Ret = new uint[Number];
for (int i = 0; i < Number; i++)
{
Ret[i] = (uint)ColorValues[ColorValuesPosition++];
}
return Ret;
}
static int[] ReadIntColorValues(int Number, int[] ColorValues, ref int ColorValuesPosition)
{
int[] Ret = new int[Number];
for (int i = 0; i < Number; i++)
{
Ret[i] = ColorValues[ColorValuesPosition++];
}
return Ret;
}
static void ComputeEndpoints(
ASTCPixel[] EndPoints,
int[] ColorValues,
uint ColorEndpointMode,
ref int ColorValuesPosition)
{
switch (ColorEndpointMode)
{
case 0:
{
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:
{
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:
{
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:
{
int[] Val = ReadIntColorValues(4, ColorValues, ref ColorValuesPosition);
BitArrayStream.BitTransferSigned(ref Val[1], ref Val[0]);
BitArrayStream.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:
{
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:
{
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:
{
int[] Val = ReadIntColorValues(6, ColorValues, ref ColorValuesPosition);
BitArrayStream.BitTransferSigned(ref Val[1], ref Val[0]);
BitArrayStream.BitTransferSigned(ref Val[3], ref Val[2]);
BitArrayStream.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:
{
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:
{
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:
{
int[] Val = ReadIntColorValues(8, ColorValues, ref ColorValuesPosition);
BitArrayStream.BitTransferSigned(ref Val[1], ref Val[0]);
BitArrayStream.BitTransferSigned(ref Val[3], ref Val[2]);
BitArrayStream.BitTransferSigned(ref Val[5], ref Val[4]);
BitArrayStream.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(
int[] OutputValues,
byte[] InputData,
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.
List<IntegerEncoded> IntegerEncodedSequence = new List<IntegerEncoded>();
BitArrayStream ColorBitStream = new BitArrayStream(new BitArray(InputData));
IntegerEncoded.DecodeIntegerSequence(IntegerEncodedSequence, 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 (IntegerEncoded IntEncoded in IntegerEncodedSequence)
{
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 = BitArrayStream.Replicate(BitValue & 1, 1, 9);
switch (IntEncoded.GetEncoding())
{
case IntegerEncoded.EIntegerEncoding.JustBits:
{
OutputValues[OutputIndices++] = BitArrayStream.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 b = (BitValue >> 1) & 1;
B = (b << 8) | (b << 4) | (b << 2) | (b << 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 b = (BitValue >> 1) & 1;
B = (b << 8) | (b << 3) | (b << 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(BitArrayStream BitStream, 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 TexelWeightParams DecodeBlockInfo(BitArrayStream BitStream)
{
TexelWeightParams 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 TexelParams;
}
// First check if the last four bits are zero
if ((ModeBits & 0xF) == 0)
{
TexelParams.Error = true;
return TexelParams;
}
// 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 TexelParams;
}
// 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 = 0;
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)
{
int[] MaxWeights = { 9, 11, 15, 19, 23, 31 };
TexelParams.MaxWeight = MaxWeights[R - 2];
}
else
{
int[] MaxWeights = { 1, 2, 3, 4, 5, 7 };
TexelParams.MaxWeight = MaxWeights[R - 2];
}
TexelParams.DualPlane = D;
return TexelParams;
}
}
}