public static void ReadRGBA16161616F(SKImageInfo imageInfo, BinaryReader r, Span <byte> data)
{
var bytes = r.ReadBytes(imageInfo.Width * imageInfo.Height * 8);
var log = 0d;
for (int i = 0, j = 0; i < bytes.Length; i += 8, j += 4)
{
var hr = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes, i + 0));
var hg = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes, i + 2));
var hb = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes, i + 4));
var lum = (hr * 0.299f) + (hg * 0.587f) + (hb * 0.114f);
log += Math.Log(0.0000000001d + lum);
}
log = Math.Exp(log / (imageInfo.Width * imageInfo.Height));
for (int i = 0, j = 0; i < bytes.Length; i += 8, j += 4)
{
var hr = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes, i + 0));
var hg = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes, i + 2));
var hb = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes, i + 4));
var ha = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes, i + 6));
var y = (hr * 0.299f) + (hg * 0.587f) + (hb * 0.114f);
var u = (hb - y) * 0.565f;
var v = (hr - y) * 0.713f;
var mul = 4.0f * y / log;
mul = mul / (1.0f + mul);
mul /= y;
hr = (float)Math.Pow((y + (1.403f * v)) * mul, 2.25f);
hg = (float)Math.Pow((y - (0.344f * u) - (0.714f * v)) * mul, 2.25f);
hb = (float)Math.Pow((y + (1.770f * u)) * mul, 2.25f);
if (hr < 0)
{
hr = 0;
}
if (hr > 1)
{
hr = 1;
}
if (hg < 0)
{
hg = 0;
}
if (hg > 1)
{
hg = 1;
}
if (hb < 0)
{
hb = 0;
}
if (hb > 1)
{
hb = 1;
}
data[j + 0] = (byte)(hr * 255); // r
data[j + 1] = (byte)(hg * 255); // g
data[j + 2] = (byte)(hb * 255); // b
data[j + 3] = (byte)(ha * 255); // a
}
}
/// <summary>
/// Read a half-precision float from a binary reader.
/// </summary>
/// <param name="reader">Binary ready.</param>
/// <returns>float.</returns>
private static float ReadHalfFloat(BinaryReader reader)
{
return(HalfTypeHelper.Convert(reader.ReadUInt16()));
}
public float[] ReadVertexAttribute(int offset, VertexBuffer vertexBuffer, VertexAttribute attribute)
{
float[] result;
offset = (int)(offset * vertexBuffer.Size) + (int)attribute.Offset;
// Useful reference: https://github.com/apitrace/dxsdk/blob/master/Include/d3dx_dxgiformatconvert.inl
switch (attribute.Type)
{
case DXGI_FORMAT.R32G32B32_FLOAT:
{
result = new float[3];
Buffer.BlockCopy(vertexBuffer.Buffer, offset, result, 0, 12);
break;
}
case DXGI_FORMAT.R16G16_UNORM:
{
var shorts = new ushort[2];
Buffer.BlockCopy(vertexBuffer.Buffer, offset, shorts, 0, 4);
result = new[]
{
shorts[0] / 65535f,
shorts[1] / 65535f,
};
break;
}
case DXGI_FORMAT.R16G16_FLOAT:
{
var shorts = new ushort[2];
Buffer.BlockCopy(vertexBuffer.Buffer, offset, shorts, 0, 4);
result = new[]
{
HalfTypeHelper.Convert(shorts[0]),
HalfTypeHelper.Convert(shorts[1]) * -1f,
};
break;
}
case DXGI_FORMAT.R32G32_FLOAT:
{
result = new float[2];
Buffer.BlockCopy(vertexBuffer.Buffer, offset, result, 0, 8);
result[1] *= -1f; // Flip texcoord
break;
}
case DXGI_FORMAT.R8G8B8A8_UINT:
case DXGI_FORMAT.R8G8B8A8_UNORM:
{
var bytes = new byte[4];
Buffer.BlockCopy(vertexBuffer.Buffer, offset, bytes, 0, 4);
result = new float[4];
for (var i = 0; i < 4; i++)
{
result[i] = attribute.Type == DXGI_FORMAT.R8G8B8A8_UNORM
? bytes[i] / 255f
: bytes[i];
}
break;
}
default:
throw new NotImplementedException($"Unsupported \"{attribute.Name}\" DXGI_FORMAT.{attribute.Type}");
}
return(result);
}
public static SKBitmap ReadRGBA16161616F(SKBitmap imageInfo, Span <byte> bytes)
{
var data = imageInfo.PeekPixels().GetPixelSpan <byte>();
var log = 0d;
for (int i = 0, j = 0; i < bytes.Length; i += 8, j += 4)
{
var hr = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes.Slice(i, 2)));
var hg = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes.Slice(i + 2, 2)));
var hb = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes.Slice(i + 4, 2)));
var lum = (hr * 0.299f) + (hg * 0.587f) + (hb * 0.114f);
log += Math.Log(0.0000000001d + lum);
}
log = Math.Exp(log / (imageInfo.Width * imageInfo.Height));
for (int i = 0, j = 0; i < bytes.Length; i += 8, j += 4)
{
var hr = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes.Slice(i, 2)));
var hg = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes.Slice(i + 2, 2)));
var hb = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes.Slice(i + 4, 2)));
var ha = HalfTypeHelper.Convert(BitConverter.ToUInt16(bytes.Slice(i + 6, 2)));
var y = (hr * 0.299f) + (hg * 0.587f) + (hb * 0.114f);
var u = (hb - y) * 0.565f;
var v = (hr - y) * 0.713f;
var mul = 4.0f * y / log;
mul = mul / (1.0f + mul);
mul /= y;
hr = (float)Math.Pow((y + (1.403f * v)) * mul, 2.25f);
hg = (float)Math.Pow((y - (0.344f * u) - (0.714f * v)) * mul, 2.25f);
hb = (float)Math.Pow((y + (1.770f * u)) * mul, 2.25f);
if (hr < 0)
{
hr = 0;
}
if (hr > 1)
{
hr = 1;
}
if (hg < 0)
{
hg = 0;
}
if (hg > 1)
{
hg = 1;
}
if (hb < 0)
{
hb = 0;
}
if (hb > 1)
{
hb = 1;
}
data[j + 0] = (byte)(hr * 255); // r
data[j + 1] = (byte)(hg * 255); // g
data[j + 2] = (byte)(hb * 255); // b
data[j + 3] = (byte)(ha * 255); // a
}
return(imageInfo);
}
public static float[] ReadVertexAttribute(int offset, OnDiskBufferData vertexBuffer, RenderInputLayoutField attribute)
{
float[] result;
offset = (int)(offset * vertexBuffer.ElementSizeInBytes) + (int)attribute.Offset;
// Useful reference: https://github.com/apitrace/dxsdk/blob/master/Include/d3dx_dxgiformatconvert.inl
switch (attribute.Format)
{
case DXGI_FORMAT.R32G32B32_FLOAT:
{
result = new float[3];
Buffer.BlockCopy(vertexBuffer.Data, offset, result, 0, 12);
break;
}
case DXGI_FORMAT.R32G32B32A32_FLOAT:
{
result = new float[4];
Buffer.BlockCopy(vertexBuffer.Data, offset, result, 0, 16);
break;
}
case DXGI_FORMAT.R16G16_UNORM:
{
var shorts = new ushort[2];
Buffer.BlockCopy(vertexBuffer.Data, offset, shorts, 0, 4);
result = new[]
{
shorts[0] / 65535f,
shorts[1] / 65535f,
};
break;
}
case DXGI_FORMAT.R16G16_FLOAT:
{
var shorts = new ushort[2];
Buffer.BlockCopy(vertexBuffer.Data, offset, shorts, 0, 4);
result = new[]
{
HalfTypeHelper.Convert(shorts[0]),
HalfTypeHelper.Convert(shorts[1]),
};
break;
}
case DXGI_FORMAT.R32_FLOAT:
{
result = new float[1];
Buffer.BlockCopy(vertexBuffer.Data, offset, result, 0, 4);
break;
}
case DXGI_FORMAT.R32G32_FLOAT:
{
result = new float[2];
Buffer.BlockCopy(vertexBuffer.Data, offset, result, 0, 8);
break;
}
case DXGI_FORMAT.R16G16_SINT:
{
var shorts = new short[2];
Buffer.BlockCopy(vertexBuffer.Data, offset, shorts, 0, 4);
result = new float[2];
for (var i = 0; i < 2; i++)
{
result[i] = shorts[i];
}
break;
}
case DXGI_FORMAT.R16G16B16A16_SINT:
{
var shorts = new short[4];
Buffer.BlockCopy(vertexBuffer.Data, offset, shorts, 0, 8);
result = new float[4];
for (var i = 0; i < 4; i++)
{
result[i] = shorts[i];
}
break;
}
case DXGI_FORMAT.R8G8B8A8_UINT:
case DXGI_FORMAT.R8G8B8A8_UNORM:
{
var bytes = new byte[4];
Buffer.BlockCopy(vertexBuffer.Data, offset, bytes, 0, 4);
result = new float[4];
for (var i = 0; i < 4; i++)
{
result[i] = attribute.Format == DXGI_FORMAT.R8G8B8A8_UNORM
? bytes[i] / 255f
: bytes[i];
}
break;
}
default:
throw new NotImplementedException($"Unsupported \"{attribute.SemanticName}\" DXGI_FORMAT.{attribute.Format}");
}
return(result);
}
