can't overload operator explicit with float arg

#ifndef HTCW_GFX_POSITIONING_HPP
#define HTCW_GFX_POSITIONING_HPP
#include "gfx_core.hpp"
#include <htcw_bits.hpp>
namespace gfx {
...
    // represents a size with integer coordinates
    template <typename T>
    struct sizex final {
        using type = sizex;
        using value_type = T;
        // the width
        T width;
        // the height
        T height;
        // constructs a new instance
        inline sizex() {}
        // constructs a new instance with the specified width and height
        constexpr inline sizex(T width, T height) : width(width), height(height) {
        }
        // increases or decreases the width and height by the specified amounts.
        constexpr sizex inflate(typename bits::signedx<T> width,typename bits::signedx<T> height) const {
            return sizex(width+this->width,height+this->height);
        }
        constexpr inline rectx<T> bounds() const;
        constexpr explicit operator sizex<bits::signedx<value_type>>() const {
            return sizex<bits::signedx<value_type>>(bits::signedx<value_type>(width),bits::signedx<value_type>(height));
        }
        constexpr explicit operator sizex<bits::unsignedx<value_type>>() const {
            return sizex<bits::unsignedx<value_type>>(bits::unsignedx<value_type>(width),bits::unsignedx<value_type>(height));
        }

        // won't compile"
        constexpr inline explicit operator sizex<float>() const {
            return sizex<float>(float(width),float(height));
        }

        constexpr inline bool operator==(const sizex& rhs) const {
            return width==rhs.width && height==rhs.height;
        }
        constexpr inline bool operator!=(const sizex& rhs) const {
            return width!=rhs.width || height!=rhs.height;
        }
        constexpr static const inline sizex min() { return { bits::num_metrics<value_type>::min,bits::num_metrics<value_type>::min }; }
        constexpr static const inline sizex max() { return { bits::num_metrics<value_type>::max,bits::num_metrics<value_type>::max }; }

        constexpr inline float aspect_ratio() const {
            return (float)width/(float)height;
        }

        constexpr size_t area() const {
            return width*height;
        }
        constexpr sizex flip() const {
            return {height,width};
        }
        constexpr static const inline sizex zero() { return { bits::num_metrics<value_type>::zero,bits::num_metrics<value_type>::zero }; }
...