internal static W3dAdaptiveDeltaAnimationChannel Parse(BinaryReader reader, W3dParseContext context, W3dAdaptiveDeltaBitCount bitCount)
{
return ParseChunk(reader, context, header =>
{
var result = new W3dAdaptiveDeltaAnimationChannel
{
NumTimeCodes = reader.ReadUInt32(),
Pivot = reader.ReadUInt16(),
VectorLength = reader.ReadByte(),
ChannelType = reader.ReadByteAsEnum<W3dAnimationChannelType>(),
Scale = reader.ReadSingle(),
};
W3dAnimationChannel.ValidateChannelDataSize(result.ChannelType, result.VectorLength);
result.Data = W3dAdaptiveDeltaData.Parse(
reader,
result.NumTimeCodes,
result.ChannelType,
result.VectorLength,
bitCount);
// Skip 3 unknown bytes at chunk end.
reader.BaseStream.Seek(3, SeekOrigin.Current);
return result;
});
}
public static W3dAnimationChannelDatum[] Decode(
W3dAdaptiveDeltaData data,
uint numFrames,
float scale)
{
var scaleFactor = 1.0f;
switch (data.BitCount)
{
// Do nothing for 4 bit deltas since they already map to [-16;16]
case W3dAdaptiveDeltaBitCount.FourBits:
break;
// When deltas are 8 bits large we need to scale them to the range [-16;16]
case W3dAdaptiveDeltaBitCount.EightBits:
scaleFactor = 1 / 16.0f;
break;
default:
throw new InvalidOperationException("Adaptive delta only supported 4 bit & 8 bit!");
}
var result = new W3dAnimationChannelDatum[numFrames];
result[0] = data.InitialDatum;
for (var i = 0; i < data.DeltaBlocks.Length; i++)
{
var deltaBlock = data.DeltaBlocks[i];
var blockIndex = deltaBlock.BlockIndex;
var blockScale = Table[blockIndex];
var deltaScale = blockScale * scale * scaleFactor;
var vectorIndex = deltaBlock.VectorIndex;
var deltas = deltaBlock.GetDeltas(data.BitCount);
for (var j = 0; j < deltas.Length; j++)
{
var idx = ((i / data.VectorLength) * 16) + j + 1;
if (idx >= numFrames)
{
break;
}
var value = result[idx - 1].GetValue(vectorIndex) + deltaScale * deltas[j];
result[idx] = result[idx].WithValue(value, vectorIndex);
idx++;
}
}
return(result);
}
internal static W3dMotionChannelAdaptiveDeltaData Parse(
BinaryReader reader,
uint numTimeCodes,
W3dAnimationChannelType channelType,
int vectorLen,
W3dAdaptiveDeltaBitCount bitCount)
{
return(new W3dMotionChannelAdaptiveDeltaData
{
Scale = reader.ReadSingle(),
Data = W3dAdaptiveDeltaData.Parse(
reader,
numTimeCodes,
channelType,
vectorLen,
bitCount)
});
}
internal static W3dAdaptiveDeltaData Parse(
BinaryReader reader,
uint numFrames,
W3dAnimationChannelType type,
int vectorLength,
W3dAdaptiveDeltaBitCount bitCount)
{
var count = (numFrames + 15) >> 4;
// First read all initial values
var result = new W3dAdaptiveDeltaData
{
BitCount = bitCount,
VectorLength = vectorLength,
InitialDatum = W3dAnimationChannelDatum.Parse(reader, type)
};
var numBits = (int)bitCount;
// Then read the interleaved delta blocks
var deltaBlocks = new W3dAdaptiveDeltaBlock[count * vectorLength];
for (var i = 0; i < count; i++)
{
for (var j = 0; j < vectorLength; j++)
{
deltaBlocks[(i * vectorLength) + j] = W3dAdaptiveDeltaBlock.Parse(
reader,
j,
numBits);
}
}
result.DeltaBlocks = deltaBlocks;
return(result);
}
