Many APIs like OpenGL take arrays where the atomic unit is multiple
elements long. For example, a buffer of coordinates laid out like
:[Float] = [ x1, y1, z1, x2, y2, z2, ... , xn, yn, zn ]
I want to be able to define *in Swift* (i.e., without creating and
importing a Objective C module) a struct that preserves the layout, so that
I can do withMemoryRebound(to:capacity:_) or something similar and treat
the buffer as
struct Point
{
let x:Float,
y:Float,
z:Float
}
:[Point] = [ point1, point2, ... , pointn ]
The memory layout of the struct isn’t guaranteed, but will the layout be
guaranteed to be in declaration order if I use a tuple inside the struct
instead?
struct Point
{
let _point:(x:Float, y:Float, z:Float)
var x:Float
{
return self._point.x
}
var y:Float
{
return self._point.y
}
var z:Float
{
return self._point.z
}
}
This is an ugly workaround, but I can’t really think of any alternatives
that don’t involve “import something from Objective C”. I am aware that the
implementation of structs currently lays them out in declaration order, but
I’m looking for something that’s actually defined in the language.