template<class T, size_t Size>
struct Vc::array< T, Size >
This is std::array with additional subscript operators supporting gather and scatter operations.
The std::array documentation applies.
Gathers from structured data (AoS: arrays of struct) are possible via a special subscript operator. Example:
Vc::array<float, 100> data;
std::iota(data.begin(), data.end(), 0.f); // fill with values 0, 1, 2, ...
auto indexes = float_v::IndexType::IndexesFromZero();
float_v gathered = data[indexes]; // gathered == [0, 1, 2, ...]
This also works for gathers into arrays of structures:
struct Point { float x, y, z; };
Vc::array<Point, 100> points;
// fill points ...
auto indexes = float_v::IndexType::IndexesFromZero();
float_v xs = data[indexes][&Point::x]; // [points[0].x, points[1].x, points[2].x, ...]
float_v ys = data[indexes][&Point::y]; // [points[0].y, points[1].y, points[2].y, ...]
float_v zs = data[indexes][&Point::z]; // [points[0].z, points[1].z, points[2].z, ...]
Arrays may also be nested:
:
Vc::array<Vc::array<float, 3>, 100> points;
// fill points ...
auto indexes = float_v::IndexType::IndexesFromZero();
float_v xs = data[indexes][0]; // [points[0][0], points[1][0], points[2][0], ...]
float_v ys = data[indexes][1]; // [points[0][1], points[1][1], points[2][1], ...]
float_v zs = data[indexes][2]; // [points[0][2], points[1][2], points[2][2], ...]
Definition at line 86 of file array.
1.8.13