public static int CharToUtf8(char character, ref FourBytes utf8)
{
var codepoint = (ushort)character;
if (codepoint <= 0x7f)
{
utf8.B0 = (byte)codepoint;
return 1;
}
if (codepoint <= 0x7ff)
{
utf8.B0 = (byte)(0xC0 | ((codepoint & 0x07C0) >> 6));
utf8.B1 = (byte)(0x80 | (codepoint & 0x3F));
return 2;
}
if (!char.IsSurrogate(character))
{
utf8.B0 = (byte)(0xE0 | ((codepoint & 0xF000) >> 12));
utf8.B1 = (byte)(0x80 | ((codepoint & 0x0FC0) >> 6));
utf8.B2 = (byte)(0x80 | (codepoint & 0x003F));
return 3;
}
utf8.B3 = 0;
throw new NotImplementedException();
}
public static int CharToUtf8(char c, ref FourBytes utf8)
{
var codepoint = (ushort)c;
if (codepoint <= 0x7f)
{
utf8.B0 = (byte)codepoint;
return(1);
}
if (codepoint <= 0x7ff)
{
utf8.B0 = (byte)(0xC0 | ((codepoint & 0x07C0) >> 6));
utf8.B1 = (byte)(0x80 | (codepoint & 0x3F));
return(2);
}
if (!char.IsSurrogate(c))
{
utf8.B0 = (byte)(0xE0 | ((codepoint & 0xF000) >> 12));
utf8.B1 = (byte)(0x80 | ((codepoint & 0x0FC0) >> 6));
utf8.B2 = (byte)(0x80 | (codepoint & 0x003F));
return(3);
}
utf8.B3 = 0;
throw new NotImplementedException();
}
public static bool TryFormat(this char value, Span <byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if (formattingData.IsUtf16)
{
if (buffer.Length < 2)
{
bytesWritten = 0;
return(false);
}
buffer[0] = (byte)value;
buffer[1] = (byte)(value >> 8);
bytesWritten = 2;
return(true);
}
if (buffer.Length < 1)
{
bytesWritten = 0;
return(false);
}
// fast path for ASCII
if (value <= 127)
{
buffer[0] = (byte)value;
bytesWritten = 1;
return(true);
}
var encoded = new FourBytes();
bytesWritten = Utf8Encoder.CharToUtf8(value, ref encoded);
if (buffer.Length < bytesWritten)
{
bytesWritten = 0;
return(false);
}
buffer[0] = encoded.B0;
if (bytesWritten > 1)
{
buffer[1] = encoded.B1;
}
if (bytesWritten > 2)
{
buffer[2] = encoded.B2;
}
if (bytesWritten > 3)
{
buffer[3] = encoded.B3;
}
return(true);
}
public static void TestReinterpret()
{
{
TestBlah zero1 = new TestBlah()
{
a = 0, b = 0, c = 0
};
Vector3 zero2 = Unsafe.Reinterpret <TestBlah, Vector3>(zero1);
zero2.ShouldBe <Vector3>(Vector3.zero);
zero2.ShouldEqual(Vector3.zero);
TestBlah yeet = new TestBlah()
{
a = 123, b = 456, c = 789
};
Vector3 yeah = Unsafe.Reinterpret <TestBlah, Vector3>(yeet);
yeah.ShouldBe <Vector3>(new Vector3(123, 456, 789));
yeah.ShouldEqual(new Vector3(123, 456, 789));
}
{
int IEEEonePointOh = 0x3F80_0000;
float onePointOhEff = 1.0f;
int IEEEthreePointFive = 0x4060_0000;
float threePointFiveEff = 3.5f;
Unsafe.Reinterpret <int, float>(IEEEonePointOh).ShouldBe(1.0f);
Unsafe.Reinterpret <int, float>(IEEEthreePointFive).ShouldBe(3.5f);
Unsafe.Reinterpret <float, int>(onePointOhEff).ShouldBe(0x3F80_0000);
Unsafe.Reinterpret <float, int>(threePointFiveEff).ShouldBe(0x4060_0000);
}
{
int it = (unchecked ((int)0xDEADBEEF));
FourBytes f = Unsafe.Reinterpret <int, FourBytes>(it);
if (!BitConverter.IsLittleEndian)
{
f.a.ShouldBe(0xDE); f.b.ShouldBe(0xAD); f.c.ShouldBe(0xBE); f.d.ShouldBe(0xEF);
}
else
{
f.d.ShouldBe(0xDE); f.c.ShouldBe(0xAD); f.b.ShouldBe(0xBE); f.a.ShouldBe(0xEF);
}
}
}
public static char Utf8ToChar(ref FourBytes utf8)
{
throw new NotImplementedException();
}
public static char Utf8ToChar(ref FourBytes utf8)
{
throw new NotImplementedException();
}
public static bool TryFormat(this string value, Span <byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if (formattingData.IsUtf16)
{
var valueBytes = value.Length << 1;
if (valueBytes > buffer.Length)
{
bytesWritten = 0;
return(false);
}
unsafe
{
fixed(char *pCharacters = value)
{
byte *pBytes = (byte *)pCharacters;
buffer.Set(pBytes, valueBytes);
}
}
bytesWritten = valueBytes;
return(true);
}
GCHandle handle;
var byteSpan = buffer.Pin(out handle);
try {
var avaliableBytes = byteSpan.Length;
bytesWritten = 0;
for (int i = 0; i < value.Length; i++)
{
var c = value[i];
var codepoint = (ushort)c;
if (codepoint <= 0x7f) // this if block just optimizes for ascii
{
if (bytesWritten + 1 > avaliableBytes)
{
bytesWritten = 0;
return(false);
}
byteSpan[bytesWritten++] = (byte)codepoint;
}
else
{
var encoded = new FourBytes();
var bytes = Utf8Encoder.CharToUtf8(c, ref encoded);
if (bytesWritten + bytes > avaliableBytes)
{
bytesWritten = 0;
return(false);
}
byteSpan[bytesWritten] = encoded.B0;
if (bytes > 1)
{
byteSpan[bytesWritten + 1] = encoded.B1;
if (bytes > 2)
{
byteSpan[bytesWritten + 2] = encoded.B2;
if (bytes > 3)
{
byteSpan[bytesWritten + 3] = encoded.B3;
}
}
}
bytesWritten += bytes;
}
}
return(true);
}
finally
{
handle.Free();
}
}
