scale3.hpp

// Copyright Take Vos 2021-2022.
// 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 "scale2.hpp"
#include "vector3.hpp"
#include "extent3.hpp"
#include "../macros.hpp"
 
namespace hi { inline namespace v1 {
 
class scale3 {
public:
    using array_type = simd<float, 4>;
    using value_type = array_type::value_type;
 
    constexpr scale3(scale3 const&) noexcept = default;
    constexpr scale3(scale3&&) noexcept = default;
    constexpr scale3& operator=(scale3 const&) noexcept = default;
    constexpr scale3& operator=(scale3&&) noexcept = default;
 
    [[nodiscard]] constexpr scale3(scale2 const& other) noexcept : _v(f32x4{other}) {}
 
    [[nodiscard]] constexpr explicit operator scale2() const noexcept
    {
        auto tmp = _v;
        tmp.z() = 1.0f;
        return scale2{tmp};
    }
 
    [[nodiscard]] constexpr explicit operator f32x4() const noexcept
    {
        return _v;
    }
 
    [[nodiscard]] constexpr explicit scale3(f32x4 const& v) noexcept : _v(v)
    {
        hi_axiom(holds_invariant());
    }
 
    [[nodiscard]] constexpr explicit scale3(vector3 const& v) noexcept : _v(static_cast<f32x4>(v).xyz1()) {}
 
    [[nodiscard]] constexpr scale3() noexcept : _v(1.0f, 1.0f, 1.0f, 1.0f) {}
 
    [[nodiscard]] constexpr scale3(float value) noexcept : _v(value, value, value, 1.0f) {}
 
    [[nodiscard]] constexpr scale3(float x, float y, float z = 1.0f) noexcept : _v(x, y, z, 1.0f) {}

    [[nodiscard]] constexpr static scale3 uniform(extent3 src_extent, extent3 dst_extent) noexcept
    {
        hilet non_uniform_scale = static_cast<f32x4>(dst_extent).xyzx() / static_cast<f32x4>(src_extent).xyzx();
        hilet uniform_scale = std::min({non_uniform_scale.x(), non_uniform_scale.y(), non_uniform_scale.z()});
        return scale3{uniform_scale};
    }
 
    [[nodiscard]] constexpr friend bool operator==(scale3 const& lhs, scale3 const& rhs) noexcept
    {
        return equal(lhs._v, rhs._v);
    }
 
    [[nodiscard]] constexpr bool holds_invariant() const noexcept
    {
        return _v.w() == 1.0f;
    }
 
    [[nodiscard]] constexpr float& x() noexcept
    {
        return _v.x();
    }
 
    [[nodiscard]] constexpr float& y() noexcept
    {
        return _v.y();
    }
 
    [[nodiscard]] constexpr float& z() noexcept
    {
        return _v.z();
    }
 
    [[nodiscard]] constexpr float x() const noexcept
    {
        return _v.x();
    }
 
    [[nodiscard]] constexpr float y() const noexcept
    {
        return _v.y();
    }
 
    [[nodiscard]] constexpr float z() const noexcept
    {
        return _v.z();
    }
 
private:
    array_type _v;
};
 
[[nodiscard]] constexpr scale3 operator/(extent3 const& lhs, extent3 const& rhs) noexcept
{
    return scale3{f32x4{lhs}.xyz1() / f32x4{rhs}.xyz1()};
}
 
}} // namespace hi::v1