src/Math/Random.hpp


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#pragma once

#include "array"
#include "Common.hpp"

namespace Math::Random {

std::array<uint8_t, 4> break_float(float f);
float to_float(uint8_t u);

uint8_t hash(uint8_t x);

float random();

template <size_t D>
struct Noise {
    float at(Vector<D> pos) const {
        uint8_t to_hash[D * 4];
        for (int i = 0; i < D; i++) {
            auto b = break_float(pos[i]);
            to_hash[i*4] = b[0]; to_hash[i*4+1] = b[1]; to_hash[i*4+2] = b[2]; to_hash[i*4+3] = b[3];
        }
        uint8_t h = 0;
        for (int i = 0; i < D * 4; i++) {
            h = hash(h) + to_hash[i];
        }
        return to_float(h);
    }
};

}