gvox-sys 1.3.0

Voxel file format parser
Documentation 
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#pragma once

#include <cstdlib>
#include <array>

static constexpr auto ceil_log2(uint32_t x) -> uint32_t {
    constexpr auto const t = std::array<uint32_t, 5>{
        0xFFFF0000u,
        0x0000FF00u,
        0x000000F0u,
        0x0000000Cu,
        0x00000002u};

    uint32_t y = (((x & (x - 1)) == 0) ? 0 : 1);
    int j = 16;

    for (uint32_t const i : t) {
        int const k = (((x & i) == 0) ? 0 : j);
        y += static_cast<uint32_t>(k);
        x >>= k;
        j >>= 1;
    }

    return y;
}