extent.hpp

// Copyright Take Vos 2021.
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt)
 
#pragma once
 
#include "vector.hpp"
#include "../numeric_array.hpp"
 
namespace tt {
namespace geo {
 
template<int D>
class extent {
public:
    static_assert(D == 2 || D == 3, "Only 2D or 3D extents are supported");
 
    constexpr extent(extent const &) noexcept = default;
    constexpr extent(extent &&) noexcept = default;
    constexpr extent &operator=(extent const &) noexcept = default;
    constexpr extent &operator=(extent &&) noexcept = default;
 
    template<int E>
    requires(E < D) [[nodiscard]] constexpr extent(extent<E> const &other) noexcept : _v(static_cast<f32x4>(other))
    {
        tt_axiom(is_valid());
    }
 
    [[nodiscard]] constexpr explicit operator f32x4() const noexcept
    {
        return _v;
    }
 
    [[nodiscard]] constexpr explicit extent(f32x4 const &other) noexcept : _v(other)
    {
        tt_axiom(is_valid());
    }
 
    [[nodiscard]] constexpr extent() noexcept : _v(0.0f, 0.0f, 0.0f, 0.0f) {}
 
    [[nodiscard]] constexpr extent(float width, float height) noexcept requires(D == 2) : _v(width, height, 0.0f, 0.0f) {}
 
    [[nodiscard]] constexpr extent(float width, float height, float depth = 0.0f) noexcept requires(D == 3) : _v(width, height, depth, 0.0f) {}
 
    [[nodiscard]] constexpr float &width() noexcept
    {
        return _v.x();
    }
 
    [[nodiscard]] constexpr float &height() noexcept
    {
        return _v.y();
    }
 
    [[nodiscard]] constexpr float &depth() noexcept requires(D == 3)
    {
        return _v.z();
    }
 
    [[nodiscard]] constexpr float const &width() const noexcept
    {
        return _v.x();
    }
 
    [[nodiscard]] constexpr float const &height() const noexcept
    {
        return _v.y();
    }
 
    [[nodiscard]] constexpr float const &depth() const noexcept requires(D == 3)
    {
        return _v.z();
    }
 
    [[nodiscard]] constexpr friend extent operator+(extent const &lhs, extent const &rhs) noexcept
    {
        tt_axiom(lhs.is_valid() && rhs.is_valid());
        return extent{lhs._v + rhs._v};
    }
 
    [[nodiscard]] constexpr friend extent operator-(extent const &lhs, extent const &rhs) noexcept
    {
        tt_axiom(lhs.is_valid() && rhs.is_valid());
        return extent{lhs._v - rhs._v};
    }
 
    [[nodiscard]] constexpr friend extent operator*(extent const &lhs, float const &rhs) noexcept
    {
        tt_axiom(lhs.is_valid());
        return extent{lhs._v * rhs};
    }
 
    [[nodiscard]] constexpr friend extent operator*(float const &lhs, extent const &rhs) noexcept
    {
        tt_axiom(rhs.is_valid());
        return extent{lhs * rhs._v};
    }
 
    [[nodiscard]] constexpr friend bool operator==(extent const &lhs, extent const &rhs) noexcept
    {
        tt_axiom(lhs.is_valid() && rhs.is_valid());
        return lhs._v == rhs._v;
    }
 
    [[nodiscard]] constexpr friend float squared_hypot(extent const &rhs) noexcept
    {
        tt_axiom(rhs.is_valid());
        return squared_hypot<element_mask>(rhs._v);
    }
 
    [[nodiscard]] constexpr friend float hypot(extent const &rhs) noexcept
    {
        tt_axiom(rhs.is_valid());
        return hypot<element_mask>(rhs._v);
    }
 
    [[nodiscard]] constexpr friend float rcp_hypot(extent const &rhs) noexcept
    {
        tt_axiom(rhs.is_valid());
        return rcp_hypot<element_mask>(rhs._v);
    }
 
    [[nodiscard]] constexpr friend extent normalize(extent const &rhs) noexcept
    {
        tt_axiom(rhs.is_valid());
        return extent{normalize<element_mask>(rhs._v)};
    }
 
    [[nodiscard]] constexpr bool is_valid() const noexcept
    {
        return _v.w() == 0.0f && (D == 3 || _v.z() == 0.0f);
    }
 
private:
    f32x4 _v;
 
    static constexpr size_t element_mask = (1_uz << D) - 1;
};
 
}
 
using extent2 = geo::extent<2>;
using extent3 = geo::extent<3>;
 
} // namespace tt