voxel-engine/include/OpenSimplexNoise.h

49 lines
1.3 KiB
C
Raw Normal View History

/**
Open Simple Noise for C++
Port to C++ from https://gist.github.com/KdotJPG/b1270127455a94ac5d19
by Rickard Lundberg, 2019.
*/
#pragma once
#include <cstdint>
#include <array>
namespace OpenSimplexNoise
{
class Noise
{
public:
Noise();
Noise(int64_t seed);
//2D Open Simplex Noise.
double eval(const double x, const double y) const;
//3D Open Simplex Noise.
double eval(double x, double y, double z) const;
//4D Open Simplex Noise.
double eval(double x, double y, double z, double w) const;
private:
const double m_stretch2d;
const double m_squish2d;
const double m_stretch3d;
const double m_squish3d;
const double m_stretch4d;
const double m_squish4d;
const double m_norm2d;
const double m_norm3d;
const double m_norm4d;
const long m_defaultSeed;
std::array<short, 256> m_perm;
std::array<short, 256> m_permGradIndex3d;
std::array<char, 16> m_gradients2d;
std::array<char, 72> m_gradients3d;
std::array<char, 256> m_gradients4d;
double extrapolate(int xsb, int ysb, double dx, double dy) const;
double extrapolate(int xsb, int ysb, int zsb, double dx, double dy, double dz) const;
double extrapolate(int xsb, int ysb, int zsb, int wsb, double dx, double dy, double dz, double dw) const;
};
}