Script, that generates random noise for SSAO algorithms

RandomSSAOKernelGen.cpp

// g++ -std=c++14 -O3 -mavx2 -march=native -msse4.2 -fno-rtti -fno-stack-protector -fno-exceptions -static-libstdc++ -static-libgcc RandomSSAOKernelGen.cpp -o RandomSSAOKernelGen.exe
#include <stdio.h>
// https://github.com/benanil/ASTL/blob/master/Random.hpp
#include "../ASTL/Random.hpp"
// https://github.com/benanil/ASTL/blob/master/Math/Vector.hpp
#include "../ASTL/Math/Vector.hpp"

Vector3f GenKernelVec(uint64_t xoro[2], float i, float kernelSize)
{
    Vector3f vec;
    vec.x = Random::NextFloat01(Random::Xoroshiro128Plus(xoro)) * 2.0f - 1.0f;
    vec.y = Random::NextFloat01(Random::Xoroshiro128Plus(xoro)) * 2.0f - 1.0f;
    vec.z = Random::NextFloat01(Random::Xoroshiro128Plus(xoro));
    vec.NormalizeSelf();
    float scale = i / kernelSize;
    scale = Lerp(0.1f, 1.0f, scale * scale);
    vec *= scale;
    return vec;
}

void CreateSSAOKernel(float kernelSize)
{
    FILE* file = fopen("RandomShaderVectors.txt", "wb");
    fprintf(file, "const float KernelSizef = %f;\n", kernelSize);
    fprintf(file, "const int KernelSize = %i;\n", (int)kernelSize);
    fprintf(file, "mediump vec3 SSAOKernel[%i] = vec3[%i](\n", (int)kernelSize, (int)kernelSize);
    
    uint64_t xoro[2];
    Random::Xoroshiro128PlusInit(xoro);
    for (int i = 0; i < 32; i++) Random::Xoroshiro128Plus(xoro); // < heat the random num generator

    for (float i = 0.0; i < kernelSize - 1.0; i += 1.0)
    {
        Vector3f vec = GenKernelVec(xoro, i, kernelSize);
        fprintf(file, "    vec3(%f, %f, %f),\n", vec.x, vec.y, vec.z);
    }
    Vector3f vec = GenKernelVec(xoro, kernelSize-1.0, kernelSize);
    fprintf(file, "    vec3(%f, %f, %f));\n\n", vec.x, vec.y, vec.z);

    fprintf(file, "mediump vec2 Noise[32] = vec2[32](\n");
    for (int i = 0; i < 31; i++)
    {
        fprintf(file, "    vec2(%f, %f),\n", 
                Random::NextFloat01(Random::Xoroshiro128Plus(xoro)) * 2.0 - 1.0,
                Random::NextFloat01(Random::Xoroshiro128Plus(xoro)) * 2.0 - 1.0);
    }
    fprintf(file, "    vec2(%f, %f));", Random::NextFloat01(Random::Xoroshiro128Plus(xoro)) * 2.0 - 1.0,
                                        Random::NextFloat01(Random::Xoroshiro128Plus(xoro)) * 2.0 - 1.0);

    fclose(file);
}

int main(int argc, char** argv)
{
    float kernelSize = 42.0;
    if (argc > 1)
    {
        const char* buff = argv[1];
        kernelSize = ParseFloat(buff);
        if (kernelSize < 8.0) kernelSize = 42.0f;
    }
    CreateSSAOKernel(kernelSize);
    return 0;
}