Better space-efficiency with Unsafe.*

[SupinePandora43]

[Variant]
readonly partial struct SceneObjectParameter
{
	static partial void VariantOf(
		double @double,
		float @float,
		int @int
	);
}

internally uses

private readonly struct Union
{
	double @double;
	float @float;
	int @int;
}

but a more space-efficient structure can be used instead:

[StructLayout(LayoutKind.Explicit, Size = 8)]
private readonly struct Union
{
	double @double;
}

with the use of Unsafe.BitCast<TFrom,TTo>/Unsafe.As<TFrom,TTo> for access.

Reference types can use a single object.

[mknejp]

Yes, you are right. Layout optimization is currently disabled because I ran into problems with TypeLoadException. It's still on my radar but I have to find the time to do it.