AABB.h

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#pragma once

#include "Utilities/Math/Math.h"

namespace MxEngine
{
    class AABB
    {
    public:
        Vector3 Min = MakeVector3(0.0f);
        Vector3 Max = MakeVector3(0.0f);

        constexpr Vector3 Length() const
        {
            return Max - Min;
        }

        constexpr Vector3 GetCenter() const
        {
            return (Max + Min) * 0.5f;
        }
    };

    inline constexpr AABB operator*(const AABB& box, const Vector3& scale)
    {
        return AABB{ box.Min * scale, box.Max * scale };
    }

    inline constexpr AABB operator/(const AABB& box, const Vector3& scale)
    {
        return AABB{ box.Min / scale, box.Max / scale };
    }

    inline constexpr AABB operator+(const AABB& box, const Vector3& translate)
    {
        return AABB{ box.Min + translate, box.Max + translate };
    }

    inline constexpr AABB operator-(const AABB& box, const Vector3& translate)
    {
        return AABB{ box.Min - translate, box.Max - translate };
    }

    inline AABB operator*(const AABB& box, const Matrix4x4& matrix)
    {
        std::array<Vector3, 8> vecs;
        vecs =
        {
            matrix * MakeVector4(box.Min.x, box.Min.y, box.Min.z, 1.0f),
            matrix * MakeVector4(box.Min.x, box.Min.y, box.Max.z, 1.0f),
            matrix * MakeVector4(box.Min.x, box.Max.y, box.Min.z, 1.0f),
            matrix * MakeVector4(box.Min.x, box.Max.y, box.Max.z, 1.0f),
            matrix * MakeVector4(box.Max.x, box.Min.y, box.Min.z, 1.0f),
            matrix * MakeVector4(box.Max.x, box.Min.y, box.Max.z, 1.0f),
            matrix * MakeVector4(box.Max.x, box.Max.y, box.Min.z, 1.0f),
            matrix * MakeVector4(box.Max.x, box.Max.y, box.Max.z, 1.0f),
        };
        auto minmax = MinMaxComponents(vecs.data(), vecs.size());
        return AABB{ minmax.first, minmax.second };
    }
}