public int Pack()
{
AstcPixel newPixel = new AstcPixel(A, R, G, B);
byte[] eightBitDepth = { 8, 8, 8, 8 };
newPixel.ChangeBitDepth(eightBitDepth);
return((byte)newPixel.A << 24 |
(byte)newPixel.B << 16 |
(byte)newPixel.G << 8 |
(byte)newPixel.R << 0);
}
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?)");
}
}
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);
}
