Noise.cpp

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#include "Globals.h"  // NOTE: MSVC stupidness requires this to be the same across all modules
 
#include "Noise.h"
 
#define FAST_FLOOR(x) (((x) < 0) ? ((static_cast<int>(x)) - 1) : (static_cast<int>(x)))
 
 
 
 
 
#if 0
static class cImprovedPerlinNoiseTest
{
public:
    cImprovedPerlinNoiseTest(void)
    {
        printf("Performing Improved Perlin Noise tests...\n");
        TestImage();
        TestSpeed();
        TestSpeedArr();
        printf("Improved Perlin Noise tests complete.\n");
    }
 
 
    void TestImage(void)
    {
        static const int SIZE_X = 256;
        static const int SIZE_Y = 256;
        static const int SIZE_Z = 16;
 
        cImprovedNoise noise(1);
        std::unique_ptr<NOISE_DATATYPE[]> arr(new NOISE_DATATYPE[SIZE_X * SIZE_Y * SIZE_Z]);
        noise.Generate3D(arr.get(), SIZE_X, SIZE_Y, SIZE_Z, 0, 14, 0, 14, 0, 14);
        Debug3DNoise(arr.get(), SIZE_X, SIZE_Y, SIZE_Z, "ImprovedPerlinNoiseTest3D", 128);
        noise.Generate2D(arr.get(), SIZE_X, SIZE_Y, 0, 14, 15, 28);
        Debug2DNoise(arr.get(), SIZE_X, SIZE_Y, "ImprovedPerlinNoiseTest2D", 128);
    }
 
 
    void TestSpeed(void)
    {
        cImprovedNoise improvedNoise(1);
        cNoise         noise(1);
        cTimer timer;
 
        // Measure the improvedNoise:
        NOISE_DATATYPE sum = 0;
        long long start = timer.GetNowTime();
        for (int i = 0; i < 100000000; i++)
        {
            sum += improvedNoise.GetValueAt(i, 0, -i);
        }
        long long finish = timer.GetNowTime();
        printf("cImprovedNoise took %.2f seconds; total is %f.\n", static_cast<float>(finish - start) / 1000.0f, sum);
 
        // Measure the cubicNoise:
        sum = 0;
        start = timer.GetNowTime();
        for (int i = 0; i < 100000000; i++)
        {
            sum += noise.IntNoise3D(i, 0, -i);
        }
        finish = timer.GetNowTime();
        printf("cCubicNoise took %.2f seconds; total is %f.\n", static_cast<float>(finish - start) / 1000.0f, sum);
    }
 
 
    void TestSpeedArr(void)
    {
        static const int SIZE_X = 256;
        static const int SIZE_Y = 256;
        static const int SIZE_Z = 16;
 
        std::unique_ptr<NOISE_DATATYPE[]> arr(new NOISE_DATATYPE[SIZE_X * SIZE_Y * SIZE_Z]);
        cTimer timer;
        cImprovedNoise improvedNoise(1);
        cCubicNoise    cubicNoise(1);
 
        // Measure the improvedNoise:
        long long start = timer.GetNowTime();
        for (int i = 0; i < 40; i++)
        {
            improvedNoise.Generate3D(arr.get(), SIZE_X, SIZE_Y, SIZE_Z, 0, 14, 0, 14, 0, 14);
        }
        long long finish = timer.GetNowTime();
        printf("cImprovedNoise(arr) took %.2f seconds.\n", static_cast<float>(finish - start) / 1000.0f);
 
        // Measure the cubicNoise:
        start = timer.GetNowTime();
        for (int i = 0; i < 40; i++)
        {
            cubicNoise.Generate3D(arr.get(), SIZE_X, SIZE_Y, SIZE_Z, 0, 14, 0, 14, 0, 14);
        }
        finish = timer.GetNowTime();
        printf("cCubicNoise(arr) took %.2f seconds.\n", static_cast<float>(finish - start) / 1000.0f);
    }
} g_Test;
 
#endif
 
 
 
 
 
// Globals:
 
void Debug3DNoise(const NOISE_DATATYPE * a_Noise, size_t a_SizeX, size_t a_SizeY, size_t a_SizeZ, const AString & a_FileNameBase, NOISE_DATATYPE a_Coeff)
{
    const int BUF_SIZE = 512;
    ASSERT(a_SizeX <= BUF_SIZE);  // Just stretch it, if needed
 
    // Save in XY cuts:
    cFile f1;
    if (f1.Open(fmt::format(FMT_STRING("{}_XY ({}).grab"), a_FileNameBase, a_SizeX), cFile::fmWrite))
    {
        for (size_t z = 0; z < a_SizeZ; z++)
        {
            for (size_t y = 0; y < a_SizeY; y++)
            {
                size_t idx = y * a_SizeX + z * a_SizeX * a_SizeY;
                unsigned char buf[BUF_SIZE];
                for (size_t x = 0; x < a_SizeX; x++)
                {
                    buf[x] = static_cast<unsigned char>(Clamp(static_cast<int>(128 + a_Coeff * a_Noise[idx++]), 0, 255));
                }
                f1.Write(buf, a_SizeX);
            }  // for y
            unsigned char buf[BUF_SIZE];
            memset(buf, 0, a_SizeX);
            f1.Write(buf, a_SizeX);
        }  // for z
    }  // if (XY file open)
 
    cFile f2;
    if (f2.Open(fmt::format(FMT_STRING("{}_XZ ({}).grab"), a_FileNameBase, a_SizeX), cFile::fmWrite))
    {
        for (size_t y = 0; y < a_SizeY; y++)
        {
            for (size_t z = 0; z < a_SizeZ; z++)
            {
                size_t idx = y * a_SizeX + z * a_SizeX * a_SizeY;
                unsigned char buf[BUF_SIZE];
                for (size_t x = 0; x < a_SizeX; x++)
                {
                    buf[x] = static_cast<unsigned char>(Clamp(static_cast<int>(128 + a_Coeff * a_Noise[idx++]), 0, 255));
                }
                f2.Write(buf, a_SizeX);
            }  // for z
            unsigned char buf[BUF_SIZE];
            memset(buf, 0, a_SizeX);
            f2.Write(buf, a_SizeX);
        }  // for y
    }  // if (XZ file open)
}
 
 
 
 
 
void Debug2DNoise(const NOISE_DATATYPE * a_Noise, size_t a_SizeX, size_t a_SizeY, const AString & a_FileNameBase, NOISE_DATATYPE a_Coeff)
{
    const int BUF_SIZE = 512;
    ASSERT(a_SizeX <= BUF_SIZE);  // Just stretch it, if needed
 
    cFile f1;
    if (f1.Open(fmt::format(FMT_STRING("{} ({}).grab"), a_FileNameBase, a_SizeX), cFile::fmWrite))
    {
        for (size_t y = 0; y < a_SizeY; y++)
        {
            size_t idx = y * a_SizeX;
            unsigned char buf[BUF_SIZE];
            for (size_t x = 0; x < a_SizeX; x++)
            {
                buf[x] = static_cast<unsigned char>(Clamp(static_cast<int>(128 + a_Coeff * a_Noise[idx++]), 0, 255));
            }
            f1.Write(buf, a_SizeX);
        }  // for y
    }  // if (file open)
}
 
 
 
 
 
// cCubicCell2D:
 
class cCubicCell2D
{
public:
    cCubicCell2D(
        const cNoise & a_Noise,    
        NOISE_DATATYPE * a_Array,  
        int a_SizeX, int a_SizeY,  
        const NOISE_DATATYPE * a_FracX,  
        const NOISE_DATATYPE * a_FracY   
    );
 
    void Generate(
        int a_FromX, int a_ToX,
        int a_FromY, int a_ToY
    );
 
    void InitWorkRnds(int a_FloorX, int a_FloorY);
 
    void Move(int a_NewFloorX, int a_NewFloorY);
 
protected:
    typedef NOISE_DATATYPE Workspace[4][4];
 
    const cNoise & m_Noise;
 
    Workspace * m_WorkRnds;  
    Workspace m_Workspace1;  
    Workspace m_Workspace2;  
    int m_CurFloorX;
    int m_CurFloorY;
 
    NOISE_DATATYPE * m_Array;
    int m_SizeX, m_SizeY;
    const NOISE_DATATYPE * m_FracX;
    const NOISE_DATATYPE * m_FracY;
} ;
 
 
 
 
 
cCubicCell2D::cCubicCell2D(
    const cNoise & a_Noise,    
    NOISE_DATATYPE * a_Array,  
    int a_SizeX, int a_SizeY,  
    const NOISE_DATATYPE * a_FracX,  
    const NOISE_DATATYPE * a_FracY   
) :
    m_Noise(a_Noise),
    m_WorkRnds(&m_Workspace1),
    m_CurFloorX(0),
    m_CurFloorY(0),
    m_Array(a_Array),
    m_SizeX(a_SizeX),
    m_SizeY(a_SizeY),
    m_FracX(a_FracX),
    m_FracY(a_FracY)
{
}
 
 
 
 
 
void cCubicCell2D::Generate(
    int a_FromX, int a_ToX,
    int a_FromY, int a_ToY
)
{
    for (int y = a_FromY; y < a_ToY; y++)
    {
        NOISE_DATATYPE Interp[4];
        NOISE_DATATYPE FracY = m_FracY[y];
        Interp[0] = cNoise::CubicInterpolate((*m_WorkRnds)[0][0], (*m_WorkRnds)[0][1], (*m_WorkRnds)[0][2], (*m_WorkRnds)[0][3], FracY);
        Interp[1] = cNoise::CubicInterpolate((*m_WorkRnds)[1][0], (*m_WorkRnds)[1][1], (*m_WorkRnds)[1][2], (*m_WorkRnds)[1][3], FracY);
        Interp[2] = cNoise::CubicInterpolate((*m_WorkRnds)[2][0], (*m_WorkRnds)[2][1], (*m_WorkRnds)[2][2], (*m_WorkRnds)[2][3], FracY);
        Interp[3] = cNoise::CubicInterpolate((*m_WorkRnds)[3][0], (*m_WorkRnds)[3][1], (*m_WorkRnds)[3][2], (*m_WorkRnds)[3][3], FracY);
        int idx = y * m_SizeX + a_FromX;
        for (int x = a_FromX; x < a_ToX; x++)
        {
            m_Array[idx++] = cNoise::CubicInterpolate(Interp[0], Interp[1], Interp[2], Interp[3], m_FracX[x]);
        }  // for x
    }  // for y
}
 
 
 
 
 
void cCubicCell2D::InitWorkRnds(int a_FloorX, int a_FloorY)
{
    m_CurFloorX = a_FloorX;
    m_CurFloorY = a_FloorY;
    for (int x = 0; x < 4; x++)
    {
        int cx = a_FloorX + x - 1;
        for (int y = 0; y < 4; y++)
        {
            int cy = a_FloorY + y - 1;
            (*m_WorkRnds)[x][y] = static_cast<NOISE_DATATYPE>(m_Noise.IntNoise2D(cx, cy));
        }
    }
}
 
 
 
 
 
void cCubicCell2D::Move(int a_NewFloorX, int a_NewFloorY)
{
    // Swap the doublebuffer:
    int OldFloorX = m_CurFloorX;
    int OldFloorY = m_CurFloorY;
    Workspace * OldWorkRnds = m_WorkRnds;
    m_WorkRnds = (m_WorkRnds == &m_Workspace1) ? &m_Workspace2 : &m_Workspace1;
 
    // Reuse as much of the old workspace as possible:
    int DiffX = OldFloorX - a_NewFloorX;
    int DiffY = OldFloorY - a_NewFloorY;
    for (int x = 0; x < 4; x++)
    {
        int cx = a_NewFloorX + x - 1;
        int OldX = x - DiffX;  // Where would this X be in the old grid?
        for (int y = 0; y < 4; y++)
        {
            int cy = a_NewFloorY + y - 1;
            int OldY = y - DiffY;  // Where would this Y be in the old grid?
            if ((OldX >= 0) && (OldX < 4) && (OldY >= 0) && (OldY < 4))
            {
                (*m_WorkRnds)[x][y] = (*OldWorkRnds)[OldX][OldY];
            }
            else
            {
                (*m_WorkRnds)[x][y] = static_cast<NOISE_DATATYPE>(m_Noise.IntNoise2D(cx, cy));
            }
        }
    }
    m_CurFloorX = a_NewFloorX;
    m_CurFloorY = a_NewFloorY;
}
 
 
 
 
 
// cCubicCell3D:
 
class cCubicCell3D
{
public:
    cCubicCell3D(
        const cNoise & a_Noise,                 
        NOISE_DATATYPE * a_Array,               
        int a_SizeX, int a_SizeY, int a_SizeZ,  
        const NOISE_DATATYPE * a_FracX,         
        const NOISE_DATATYPE * a_FracY,         
        const NOISE_DATATYPE * a_FracZ          
    );
 
    void Generate(
        int a_FromX, int a_ToX,
        int a_FromY, int a_ToY,
        int a_FromZ, int a_ToZ
    );
 
    void InitWorkRnds(int a_FloorX, int a_FloorY, int a_FloorZ);
 
    void Move(int a_NewFloorX, int a_NewFloorY, int a_NewFloorZ);
 
protected:
    typedef NOISE_DATATYPE Workspace[4][4][4];
 
    const cNoise & m_Noise;
 
    Workspace * m_WorkRnds;  
    Workspace m_Workspace1;  
    Workspace m_Workspace2;  
    int m_CurFloorX;
    int m_CurFloorY;
    int m_CurFloorZ;
 
    NOISE_DATATYPE * m_Array;
    int m_SizeX, m_SizeY, m_SizeZ;
    const NOISE_DATATYPE * m_FracX;
    const NOISE_DATATYPE * m_FracY;
    const NOISE_DATATYPE * m_FracZ;
} ;
 
 
 
 
 
cCubicCell3D::cCubicCell3D(
    const cNoise & a_Noise,                 
    NOISE_DATATYPE * a_Array,               
    int a_SizeX, int a_SizeY, int a_SizeZ,  
    const NOISE_DATATYPE * a_FracX,         
    const NOISE_DATATYPE * a_FracY,         
    const NOISE_DATATYPE * a_FracZ          
) :
    m_Noise(a_Noise),
    m_WorkRnds(&m_Workspace1),
    m_CurFloorX(0),
    m_CurFloorY(0),
    m_CurFloorZ(0),
    m_Array(a_Array),
    m_SizeX(a_SizeX),
    m_SizeY(a_SizeY),
    m_SizeZ(a_SizeZ),
    m_FracX(a_FracX),
    m_FracY(a_FracY),
    m_FracZ(a_FracZ)
{
}
 
 
 
 
 
void cCubicCell3D::Generate(
    int a_FromX, int a_ToX,
    int a_FromY, int a_ToY,
    int a_FromZ, int a_ToZ
)
{
    for (int z = a_FromZ; z < a_ToZ; z++)
    {
        int idxZ = z * m_SizeX * m_SizeY;
        NOISE_DATATYPE Interp2[4][4];
        NOISE_DATATYPE FracZ = m_FracZ[z];
        for (int x = 0; x < 4; x++)
        {
            for (int y = 0; y < 4; y++)
            {
                Interp2[x][y] = cNoise::CubicInterpolate((*m_WorkRnds)[x][y][0], (*m_WorkRnds)[x][y][1], (*m_WorkRnds)[x][y][2], (*m_WorkRnds)[x][y][3], FracZ);
            }
        }
        for (int y = a_FromY; y < a_ToY; y++)
        {
            NOISE_DATATYPE Interp[4];
            NOISE_DATATYPE FracY = m_FracY[y];
            Interp[0] = cNoise::CubicInterpolate(Interp2[0][0], Interp2[0][1], Interp2[0][2], Interp2[0][3], FracY);
            Interp[1] = cNoise::CubicInterpolate(Interp2[1][0], Interp2[1][1], Interp2[1][2], Interp2[1][3], FracY);
            Interp[2] = cNoise::CubicInterpolate(Interp2[2][0], Interp2[2][1], Interp2[2][2], Interp2[2][3], FracY);
            Interp[3] = cNoise::CubicInterpolate(Interp2[3][0], Interp2[3][1], Interp2[3][2], Interp2[3][3], FracY);
            int idx = idxZ + y * m_SizeX + a_FromX;
            for (int x = a_FromX; x < a_ToX; x++)
            {
                m_Array[idx++] = cNoise::CubicInterpolate(Interp[0], Interp[1], Interp[2], Interp[3], m_FracX[x]);
            }  // for x
        }  // for y
    }  // for z
}
 
 
 
 
 
void cCubicCell3D::InitWorkRnds(int a_FloorX, int a_FloorY, int a_FloorZ)
{
    m_CurFloorX = a_FloorX;
    m_CurFloorY = a_FloorY;
    m_CurFloorZ = a_FloorZ;
    for (int x = 0; x < 4; x++)
    {
        int cx = a_FloorX + x - 1;
        for (int y = 0; y < 4; y++)
        {
            int cy = a_FloorY + y - 1;
            for (int z = 0; z < 4; z++)
            {
                int cz = a_FloorZ + z - 1;
                (*m_WorkRnds)[x][y][z] = static_cast<NOISE_DATATYPE>(m_Noise.IntNoise3D(cx, cy, cz));
            }
        }
    }
}
 
 
 
 
 
void cCubicCell3D::Move(int a_NewFloorX, int a_NewFloorY, int a_NewFloorZ)
{
    // Swap the doublebuffer:
    int OldFloorX = m_CurFloorX;
    int OldFloorY = m_CurFloorY;
    int OldFloorZ = m_CurFloorZ;
    Workspace * OldWorkRnds = m_WorkRnds;
    m_WorkRnds = (m_WorkRnds == &m_Workspace1) ? &m_Workspace2 : &m_Workspace1;
 
    // Reuse as much of the old workspace as possible:
    int DiffX = OldFloorX - a_NewFloorX;
    int DiffY = OldFloorY - a_NewFloorY;
    int DiffZ = OldFloorZ - a_NewFloorZ;
    for (int x = 0; x < 4; x++)
    {
        int cx = a_NewFloorX + x - 1;
        int OldX = x - DiffX;  // Where would this X be in the old grid?
        for (int y = 0; y < 4; y++)
        {
            int cy = a_NewFloorY + y - 1;
            int OldY = y - DiffY;  // Where would this Y be in the old grid?
            for (int z = 0; z < 4; z++)
            {
                int cz = a_NewFloorZ + z - 1;
                int OldZ = z - DiffZ;
                if ((OldX >= 0) && (OldX < 4) && (OldY >= 0) && (OldY < 4) && (OldZ >= 0) && (OldZ < 4))
                {
                    (*m_WorkRnds)[x][y][z] = (*OldWorkRnds)[OldX][OldY][OldZ];
                }
                else
                {
                    (*m_WorkRnds)[x][y][z] = static_cast<NOISE_DATATYPE>(m_Noise.IntNoise3D(cx, cy, cz));
                }
            }  // for z
        }  // for y
    }  // for x
    m_CurFloorX = a_NewFloorX;
    m_CurFloorY = a_NewFloorY;
    m_CurFloorZ = a_NewFloorZ;
}
 
 
 
 
 
// cNoise:
 
cNoise::cNoise(int a_Seed) :
    m_Seed(a_Seed)
{
}
 
 
 
 
 
cNoise::cNoise(const cNoise & a_Noise) :
    m_Seed(a_Noise.m_Seed)
{
}
 
 
 
 
 
NOISE_DATATYPE cNoise::LinearNoise1D(NOISE_DATATYPE a_X) const
{
    int BaseX = FAST_FLOOR(a_X);
    NOISE_DATATYPE FracX = a_X - BaseX;
    return LinearInterpolate(IntNoise1D(BaseX), IntNoise1D(BaseX + 1), FracX);
}
 
 
 
 
 
NOISE_DATATYPE cNoise::CosineNoise1D(NOISE_DATATYPE a_X) const
{
    int BaseX = FAST_FLOOR(a_X);
    NOISE_DATATYPE FracX = a_X - BaseX;
    return CosineInterpolate(IntNoise1D(BaseX), IntNoise1D(BaseX + 1), FracX);
}
 
 
 
 
 
NOISE_DATATYPE cNoise::CubicNoise1D(NOISE_DATATYPE a_X) const
{
    int BaseX = FAST_FLOOR(a_X);
    NOISE_DATATYPE FracX = a_X - BaseX;
    return CubicInterpolate(IntNoise1D(BaseX - 1), IntNoise1D(BaseX), IntNoise1D(BaseX + 1), IntNoise1D(BaseX + 2), FracX);
}
 
 
 
 
 
NOISE_DATATYPE cNoise::SmoothNoise1D(int a_X) const
{
    return IntNoise1D(a_X) / 2 + IntNoise1D(a_X - 1) / 4 + IntNoise1D(a_X + 1) / 4;
}
 
 
 
 
 
NOISE_DATATYPE cNoise::CubicNoise2D(NOISE_DATATYPE a_X, NOISE_DATATYPE a_Y) const
{
    const int BaseX = FAST_FLOOR(a_X);
    const int BaseY = FAST_FLOOR(a_Y);
 
    const NOISE_DATATYPE points[4][4] =
    {
        { IntNoise2D(BaseX - 1, BaseY - 1), IntNoise2D(BaseX, BaseY - 1), IntNoise2D(BaseX + 1, BaseY - 1), IntNoise2D(BaseX + 2, BaseY - 1), },
        { IntNoise2D(BaseX - 1, BaseY),     IntNoise2D(BaseX, BaseY),     IntNoise2D(BaseX + 1, BaseY),     IntNoise2D(BaseX + 2, BaseY),     },
        { IntNoise2D(BaseX - 1, BaseY + 1), IntNoise2D(BaseX, BaseY + 1), IntNoise2D(BaseX + 1, BaseY + 1), IntNoise2D(BaseX + 2, BaseY + 1), },
        { IntNoise2D(BaseX - 1, BaseY + 2), IntNoise2D(BaseX, BaseY + 2), IntNoise2D(BaseX + 1, BaseY + 2), IntNoise2D(BaseX + 2, BaseY + 2), },
    };
 
    const NOISE_DATATYPE FracX = a_X - BaseX;
    const NOISE_DATATYPE interp1 = CubicInterpolate(points[0][0], points[0][1], points[0][2], points[0][3], FracX);
    const NOISE_DATATYPE interp2 = CubicInterpolate(points[1][0], points[1][1], points[1][2], points[1][3], FracX);
    const NOISE_DATATYPE interp3 = CubicInterpolate(points[2][0], points[2][1], points[2][2], points[2][3], FracX);
    const NOISE_DATATYPE interp4 = CubicInterpolate(points[3][0], points[3][1], points[3][2], points[3][3], FracX);
 
 
    const NOISE_DATATYPE FracY = a_Y - BaseY;
    return CubicInterpolate(interp1, interp2, interp3, interp4, FracY);
}
 
 
 
 
 
NOISE_DATATYPE cNoise::CubicNoise3D(NOISE_DATATYPE a_X, NOISE_DATATYPE a_Y, NOISE_DATATYPE a_Z) const
{
    const int BaseX = FAST_FLOOR(a_X);
    const int BaseY = FAST_FLOOR(a_Y);
    const int BaseZ = FAST_FLOOR(a_Z);
 
    const NOISE_DATATYPE points1[4][4] =
    {
        { IntNoise3D(BaseX - 1, BaseY - 1, BaseZ - 1), IntNoise3D(BaseX, BaseY - 1, BaseZ - 1), IntNoise3D(BaseX + 1, BaseY - 1, BaseZ - 1), IntNoise3D(BaseX + 2, BaseY - 1, BaseZ - 1), },
        { IntNoise3D(BaseX - 1, BaseY,     BaseZ - 1), IntNoise3D(BaseX, BaseY,     BaseZ - 1), IntNoise3D(BaseX + 1, BaseY,     BaseZ - 1), IntNoise3D(BaseX + 2, BaseY,     BaseZ - 1), },
        { IntNoise3D(BaseX - 1, BaseY + 1, BaseZ - 1), IntNoise3D(BaseX, BaseY + 1, BaseZ - 1), IntNoise3D(BaseX + 1, BaseY + 1, BaseZ - 1), IntNoise3D(BaseX + 2, BaseY + 1, BaseZ - 1), },
        { IntNoise3D(BaseX - 1, BaseY + 2, BaseZ - 1), IntNoise3D(BaseX, BaseY + 2, BaseZ - 1), IntNoise3D(BaseX + 1, BaseY + 2, BaseZ - 1), IntNoise3D(BaseX + 2, BaseY + 2, BaseZ - 1), },
    };
 
    const NOISE_DATATYPE FracX = (a_X) - BaseX;
    const NOISE_DATATYPE x1interp1 = CubicInterpolate(points1[0][0], points1[0][1], points1[0][2], points1[0][3], FracX);
    const NOISE_DATATYPE x1interp2 = CubicInterpolate(points1[1][0], points1[1][1], points1[1][2], points1[1][3], FracX);
    const NOISE_DATATYPE x1interp3 = CubicInterpolate(points1[2][0], points1[2][1], points1[2][2], points1[2][3], FracX);
    const NOISE_DATATYPE x1interp4 = CubicInterpolate(points1[3][0], points1[3][1], points1[3][2], points1[3][3], FracX);
 
    const NOISE_DATATYPE points2[4][4] =
    {
        { IntNoise3D(BaseX - 1, BaseY - 1, BaseZ), IntNoise3D(BaseX, BaseY - 1, BaseZ), IntNoise3D(BaseX + 1, BaseY - 1, BaseZ), IntNoise3D(BaseX + 2, BaseY - 1, BaseZ), },
        { IntNoise3D(BaseX - 1, BaseY,     BaseZ), IntNoise3D(BaseX, BaseY,     BaseZ), IntNoise3D(BaseX + 1, BaseY,     BaseZ), IntNoise3D(BaseX + 2, BaseY,     BaseZ), },
        { IntNoise3D(BaseX - 1, BaseY + 1, BaseZ), IntNoise3D(BaseX, BaseY + 1, BaseZ), IntNoise3D(BaseX + 1, BaseY + 1, BaseZ), IntNoise3D(BaseX + 2, BaseY + 1, BaseZ), },
        { IntNoise3D(BaseX - 1, BaseY + 2, BaseZ), IntNoise3D(BaseX, BaseY + 2, BaseZ), IntNoise3D(BaseX + 1, BaseY + 2, BaseZ), IntNoise3D(BaseX + 2, BaseY + 2, BaseZ), },
    };
 
    const NOISE_DATATYPE x2interp1 = CubicInterpolate(points2[0][0], points2[0][1], points2[0][2], points2[0][3], FracX);
    const NOISE_DATATYPE x2interp2 = CubicInterpolate(points2[1][0], points2[1][1], points2[1][2], points2[1][3], FracX);
    const NOISE_DATATYPE x2interp3 = CubicInterpolate(points2[2][0], points2[2][1], points2[2][2], points2[2][3], FracX);
    const NOISE_DATATYPE x2interp4 = CubicInterpolate(points2[3][0], points2[3][1], points2[3][2], points2[3][3], FracX);
 
    const NOISE_DATATYPE points3[4][4] =
    {
        { IntNoise3D(BaseX - 1, BaseY - 1, BaseZ + 1), IntNoise3D(BaseX, BaseY - 1, BaseZ + 1), IntNoise3D(BaseX + 1, BaseY - 1, BaseZ + 1), IntNoise3D(BaseX + 2, BaseY - 1, BaseZ + 1), },
        { IntNoise3D(BaseX - 1, BaseY,     BaseZ + 1), IntNoise3D(BaseX, BaseY,     BaseZ + 1), IntNoise3D(BaseX + 1, BaseY,     BaseZ + 1), IntNoise3D(BaseX + 2, BaseY,     BaseZ + 1), },
        { IntNoise3D(BaseX - 1, BaseY + 1, BaseZ + 1), IntNoise3D(BaseX, BaseY + 1, BaseZ + 1), IntNoise3D(BaseX + 1, BaseY + 1, BaseZ + 1), IntNoise3D(BaseX + 2, BaseY + 1, BaseZ + 1), },
        { IntNoise3D(BaseX - 1, BaseY + 2, BaseZ + 1), IntNoise3D(BaseX, BaseY + 2, BaseZ + 1), IntNoise3D(BaseX + 1, BaseY + 2, BaseZ + 1), IntNoise3D(BaseX + 2, BaseY + 2, BaseZ + 1), },
    };
 
    const NOISE_DATATYPE x3interp1 = CubicInterpolate(points3[0][0], points3[0][1], points3[0][2], points3[0][3], FracX);
    const NOISE_DATATYPE x3interp2 = CubicInterpolate(points3[1][0], points3[1][1], points3[1][2], points3[1][3], FracX);
    const NOISE_DATATYPE x3interp3 = CubicInterpolate(points3[2][0], points3[2][1], points3[2][2], points3[2][3], FracX);
    const NOISE_DATATYPE x3interp4 = CubicInterpolate(points3[3][0], points3[3][1], points3[3][2], points3[3][3], FracX);
 
    const NOISE_DATATYPE points4[4][4] =
    {
        { IntNoise3D(BaseX - 1, BaseY - 1, BaseZ + 2), IntNoise3D(BaseX, BaseY - 1, BaseZ + 2), IntNoise3D(BaseX + 1, BaseY - 1, BaseZ + 2), IntNoise3D(BaseX + 2, BaseY - 1, BaseZ + 2), },
        { IntNoise3D(BaseX - 1, BaseY,     BaseZ + 2), IntNoise3D(BaseX, BaseY,     BaseZ + 2), IntNoise3D(BaseX + 1, BaseY,     BaseZ + 2), IntNoise3D(BaseX + 2, BaseY,     BaseZ + 2), },
        { IntNoise3D(BaseX - 1, BaseY + 1, BaseZ + 2), IntNoise3D(BaseX, BaseY + 1, BaseZ + 2), IntNoise3D(BaseX + 1, BaseY + 1, BaseZ + 2), IntNoise3D(BaseX + 2, BaseY + 1, BaseZ + 2), },
        { IntNoise3D(BaseX - 1, BaseY + 2, BaseZ + 2), IntNoise3D(BaseX, BaseY + 2, BaseZ + 2), IntNoise3D(BaseX + 1, BaseY + 2, BaseZ + 2), IntNoise3D(BaseX + 2, BaseY + 2, BaseZ + 2), },
    };
 
    const NOISE_DATATYPE x4interp1 = CubicInterpolate(points4[0][0], points4[0][1], points4[0][2], points4[0][3], FracX);
    const NOISE_DATATYPE x4interp2 = CubicInterpolate(points4[1][0], points4[1][1], points4[1][2], points4[1][3], FracX);
    const NOISE_DATATYPE x4interp3 = CubicInterpolate(points4[2][0], points4[2][1], points4[2][2], points4[2][3], FracX);
    const NOISE_DATATYPE x4interp4 = CubicInterpolate(points4[3][0], points4[3][1], points4[3][2], points4[3][3], FracX);
 
    const NOISE_DATATYPE FracY = (a_Y) - BaseY;
    const NOISE_DATATYPE yinterp1 = CubicInterpolate(x1interp1, x1interp2, x1interp3, x1interp4, FracY);
    const NOISE_DATATYPE yinterp2 = CubicInterpolate(x2interp1, x2interp2, x2interp3, x2interp4, FracY);
    const NOISE_DATATYPE yinterp3 = CubicInterpolate(x3interp1, x3interp2, x3interp3, x3interp4, FracY);
    const NOISE_DATATYPE yinterp4 = CubicInterpolate(x4interp1, x4interp2, x4interp3, x4interp4, FracY);
 
    const NOISE_DATATYPE FracZ = (a_Z) - BaseZ;
    return CubicInterpolate(yinterp1, yinterp2, yinterp3, yinterp4, FracZ);
}
 
 
 
 
 
// cCubicNoise:
 
cCubicNoise::cCubicNoise(int a_Seed) :
    m_Noise(a_Seed)
{
}
 
 
 
 
 
void cCubicNoise::Generate2D(
    NOISE_DATATYPE * a_Array,                        
    int a_SizeX, int a_SizeY,                        
    NOISE_DATATYPE a_StartX, NOISE_DATATYPE a_EndX,  
    NOISE_DATATYPE a_StartY, NOISE_DATATYPE a_EndY   
) const
{
    ASSERT(a_SizeX > 0);
    ASSERT(a_SizeY > 0);
    ASSERT(a_SizeX < MAX_SIZE);
    ASSERT(a_SizeY < MAX_SIZE);
    ASSERT(a_StartX < a_EndX);
    ASSERT(a_StartY < a_EndY);
 
    // Calculate the integral and fractional parts of each coord:
    int FloorX[MAX_SIZE];
    int FloorY[MAX_SIZE];
    NOISE_DATATYPE FracX[MAX_SIZE];
    NOISE_DATATYPE FracY[MAX_SIZE];
    int SameX[MAX_SIZE];
    int SameY[MAX_SIZE];
    int NumSameX, NumSameY;
    CalcFloorFrac(a_SizeX, a_StartX, a_EndX, FloorX, FracX, SameX, NumSameX);
    CalcFloorFrac(a_SizeY, a_StartY, a_EndY, FloorY, FracY, SameY, NumSameY);
 
    cCubicCell2D Cell(m_Noise, a_Array, a_SizeX, a_SizeY, FracX, FracY);
 
    Cell.InitWorkRnds(FloorX[0], FloorY[0]);
 
    // Calculate query values using Cell:
    int FromY = 0;
    for (int y = 0; y < NumSameY; y++)
    {
        int ToY = FromY + SameY[y];
        int FromX = 0;
        int CurFloorY = FloorY[FromY];
        for (int x = 0; x < NumSameX; x++)
        {
            int ToX = FromX + SameX[x];
            Cell.Generate(FromX, ToX, FromY, ToY);
            Cell.Move(FloorX[ToX], CurFloorY);
            FromX = ToX;
        }
        Cell.Move(FloorX[0], FloorY[ToY]);
        FromY = ToY;
    }
}
 
 
 
 
 
void cCubicNoise::Generate3D(
    NOISE_DATATYPE * a_Array,                        
    int a_SizeX, int a_SizeY, int a_SizeZ,           
    NOISE_DATATYPE a_StartX, NOISE_DATATYPE a_EndX,  
    NOISE_DATATYPE a_StartY, NOISE_DATATYPE a_EndY,  
    NOISE_DATATYPE a_StartZ, NOISE_DATATYPE a_EndZ   
) const
{
    ASSERT(a_SizeX < MAX_SIZE);
    ASSERT(a_SizeY < MAX_SIZE);
    ASSERT(a_SizeZ < MAX_SIZE);
    ASSERT(a_StartX < a_EndX);
    ASSERT(a_StartY < a_EndY);
    ASSERT(a_StartZ < a_EndZ);
 
    // Calculate the integral and fractional parts of each coord:
    int FloorX[MAX_SIZE];
    int FloorY[MAX_SIZE];
    int FloorZ[MAX_SIZE];
    NOISE_DATATYPE FracX[MAX_SIZE];
    NOISE_DATATYPE FracY[MAX_SIZE];
    NOISE_DATATYPE FracZ[MAX_SIZE];
    int SameX[MAX_SIZE];
    int SameY[MAX_SIZE];
    int SameZ[MAX_SIZE];
    int NumSameX, NumSameY, NumSameZ;
    CalcFloorFrac(a_SizeX, a_StartX, a_EndX, FloorX, FracX, SameX, NumSameX);
    CalcFloorFrac(a_SizeY, a_StartY, a_EndY, FloorY, FracY, SameY, NumSameY);
    CalcFloorFrac(a_SizeZ, a_StartZ, a_EndZ, FloorZ, FracZ, SameZ, NumSameZ);
 
    cCubicCell3D Cell(
        m_Noise, a_Array,
        a_SizeX, a_SizeY, a_SizeZ,
        FracX, FracY, FracZ
    );
 
    Cell.InitWorkRnds(FloorX[0], FloorY[0], FloorZ[0]);
 
    // Calculate query values using Cell:
    int FromZ = 0;
    for (int z = 0; z < NumSameZ; z++)
    {
        int ToZ = FromZ + SameZ[z];
        int CurFloorZ = FloorZ[FromZ];
        int FromY = 0;
        for (int y = 0; y < NumSameY; y++)
        {
            int ToY = FromY + SameY[y];
            int CurFloorY = FloorY[FromY];
            int FromX = 0;
            for (int x = 0; x < NumSameX; x++)
            {
                int ToX = FromX + SameX[x];
                Cell.Generate(FromX, ToX, FromY, ToY, FromZ, ToZ);
                Cell.Move(FloorX[ToX], CurFloorY, CurFloorZ);
                FromX = ToX;
            }
            Cell.Move(FloorX[0], FloorY[ToY], CurFloorZ);
            FromY = ToY;
        }  // for y
        Cell.Move(FloorX[0], FloorY[0], FloorZ[ToZ]);
        FromZ = ToZ;
    }  // for z
}
 
 
 
 
 
void cCubicNoise::CalcFloorFrac(
    int a_Size,
    NOISE_DATATYPE a_Start, NOISE_DATATYPE a_End,
    int * a_Floor, NOISE_DATATYPE * a_Frac,
    int * a_Same, int & a_NumSame
) const
{
    ASSERT(a_Size > 0);
 
    NOISE_DATATYPE val = a_Start;
    NOISE_DATATYPE dif = (a_End - a_Start) / (a_Size - 1);
    for (int i = 0; i < a_Size; i++)
    {
        a_Floor[i] = FAST_FLOOR(val);
        a_Frac[i] = val - a_Floor[i];
        val += dif;
    }
 
    // Mark up the same floor values into a_Same / a_NumSame:
    int CurFloor = a_Floor[0];
    int LastSame = 0;
    a_NumSame = 0;
    for (int i = 1; i < a_Size; i++)
    {
        if (a_Floor[i] != CurFloor)
        {
            a_Same[a_NumSame] = i - LastSame;
            LastSame = i;
            a_NumSame += 1;
            CurFloor = a_Floor[i];
        }
    }  // for i - a_Floor[]
    if (LastSame < a_Size)
    {
        a_Same[a_NumSame] = a_Size - LastSame;
        a_NumSame += 1;
    }
}
 
 
 
 
 
// cImprovedNoise:
 
cImprovedNoise::cImprovedNoise(int a_Seed)
{
    // Initialize the permutations with identity:
    for (int i = 0; i < 256; i++)
    {
        m_Perm[i] = i;
    }
 
    // Randomize the permutation table - swap each element with a random other element:
    cNoise noise(a_Seed);
    for (int i = 0; i < 256; i++)
    {
        int rnd = (noise.IntNoise1DInt(i) / 7) % 256;
        std::swap(m_Perm[i], m_Perm[rnd]);
    }
 
    // Copy the lower 256 entries into upper 256 entries:
    for (int i = 0; i < 256; i++)
    {
        m_Perm[i + 256] = m_Perm[i];
    }
}
 
 
 
 
 
void cImprovedNoise::Generate2D(
    NOISE_DATATYPE * a_Array,
    int a_SizeX, int a_SizeY,
    NOISE_DATATYPE a_StartX, NOISE_DATATYPE a_EndX,
    NOISE_DATATYPE a_StartY, NOISE_DATATYPE a_EndY
) const
{
    size_t idx = 0;
    for (int y = 0; y < a_SizeY; y++)
    {
        NOISE_DATATYPE ratioY = static_cast<NOISE_DATATYPE>(y) / (a_SizeY - 1);
        NOISE_DATATYPE noiseY = Lerp(a_StartY, a_EndY, ratioY);
        int noiseYInt = FAST_FLOOR(noiseY);
        int yCoord = noiseYInt & 255;
        NOISE_DATATYPE noiseYFrac = noiseY - noiseYInt;
        NOISE_DATATYPE fadeY = Fade(noiseYFrac);
        for (int x = 0; x < a_SizeX; x++)
        {
            NOISE_DATATYPE ratioX = static_cast<NOISE_DATATYPE>(x) / (a_SizeX - 1);
            NOISE_DATATYPE noiseX = Lerp(a_StartX, a_EndX, ratioX);
            int noiseXInt = FAST_FLOOR(noiseX);
            int xCoord = noiseXInt & 255;
            NOISE_DATATYPE noiseXFrac = noiseX - noiseXInt;
            NOISE_DATATYPE fadeX = Fade(noiseXFrac);
 
            // Hash the coordinates:
            int A  = m_Perm[xCoord] + yCoord;
            int AA = m_Perm[A];
            int AB = m_Perm[A + 1];
            int B  = m_Perm[xCoord + 1] + yCoord;
            int BA = m_Perm[B];
            int BB = m_Perm[B + 1];
 
            // Lerp the gradients:
            a_Array[idx++] = Lerp(
                Lerp(Grad(m_Perm[AA], noiseXFrac, noiseYFrac,     0), Grad(m_Perm[BA], noiseXFrac - 1, noiseYFrac,     0), fadeX),
                Lerp(Grad(m_Perm[AB], noiseXFrac, noiseYFrac - 1, 0), Grad(m_Perm[BB], noiseXFrac - 1, noiseYFrac - 1, 0), fadeX),
                fadeY
            );
        }  // for x
    }  // for y
}
 
 
 
 
 
void cImprovedNoise::Generate3D(
    NOISE_DATATYPE * a_Array,
    int a_SizeX, int a_SizeY, int a_SizeZ,
    NOISE_DATATYPE a_StartX, NOISE_DATATYPE a_EndX,
    NOISE_DATATYPE a_StartY, NOISE_DATATYPE a_EndY,
    NOISE_DATATYPE a_StartZ, NOISE_DATATYPE a_EndZ
) const
{
    size_t idx = 0;
    for (int z = 0; z < a_SizeZ; z++)
    {
        NOISE_DATATYPE ratioZ = static_cast<NOISE_DATATYPE>(z) / (a_SizeZ - 1);
        NOISE_DATATYPE noiseZ = Lerp(a_StartZ, a_EndZ, ratioZ);
        int noiseZInt = FAST_FLOOR(noiseZ);
        int zCoord = noiseZInt & 255;
        NOISE_DATATYPE noiseZFrac = noiseZ - noiseZInt;
        NOISE_DATATYPE fadeZ = Fade(noiseZFrac);
        for (int y = 0; y < a_SizeY; y++)
        {
            NOISE_DATATYPE ratioY = static_cast<NOISE_DATATYPE>(y) / (a_SizeY - 1);
            NOISE_DATATYPE noiseY = Lerp(a_StartY, a_EndY, ratioY);
            int noiseYInt = FAST_FLOOR(noiseY);
            int yCoord = noiseYInt & 255;
            NOISE_DATATYPE noiseYFrac = noiseY - noiseYInt;
            NOISE_DATATYPE fadeY = Fade(noiseYFrac);
            for (int x = 0; x < a_SizeX; x++)
            {
                NOISE_DATATYPE ratioX = static_cast<NOISE_DATATYPE>(x) / (a_SizeX - 1);
                NOISE_DATATYPE noiseX = Lerp(a_StartX, a_EndX, ratioX);
                int noiseXInt = FAST_FLOOR(noiseX);
                int xCoord = noiseXInt & 255;
                NOISE_DATATYPE noiseXFrac = noiseX - noiseXInt;
                NOISE_DATATYPE fadeX = Fade(noiseXFrac);
 
                // Hash the coordinates:
                int A  = m_Perm[xCoord] + yCoord;
                int AA = m_Perm[A] + zCoord;
                int AB = m_Perm[A + 1] + zCoord;
                int B  = m_Perm[xCoord + 1] + yCoord;
                int BA = m_Perm[B] + zCoord;
                int BB = m_Perm[B + 1] + zCoord;
 
                // Lerp the gradients:
                // TODO: This may be optimized by swapping the coords and recalculating most lerps only "once every x"
                a_Array[idx++] = Lerp(
                    Lerp(
                        Lerp(Grad(m_Perm[AA], noiseXFrac, noiseYFrac,     noiseZFrac), Grad(m_Perm[BA], noiseXFrac - 1, noiseYFrac,     noiseZFrac), fadeX),
                        Lerp(Grad(m_Perm[AB], noiseXFrac, noiseYFrac - 1, noiseZFrac), Grad(m_Perm[BB], noiseXFrac - 1, noiseYFrac - 1, noiseZFrac), fadeX),
                        fadeY
                    ),
                    Lerp(
                        Lerp(Grad(m_Perm[AA + 1], noiseXFrac, noiseYFrac,     noiseZFrac - 1), Grad(m_Perm[BA + 1], noiseXFrac - 1, noiseYFrac,     noiseZFrac - 1), fadeX),
                        Lerp(Grad(m_Perm[AB + 1], noiseXFrac, noiseYFrac - 1, noiseZFrac - 1), Grad(m_Perm[BB + 1], noiseXFrac - 1, noiseYFrac - 1, noiseZFrac - 1), fadeX),
                        fadeY
                    ),
                    fadeZ
                );
            }  // for x
        }  // for y
    }  // for z
}
 
 
 
 
 
NOISE_DATATYPE cImprovedNoise::GetValueAt(int a_X, int a_Y, int a_Z)
{
    // Hash the coordinates:
    a_X = a_X & 255;
    a_Y = a_Y & 255;
    a_Z = a_Z & 255;
    int A  = m_Perm[a_X] + a_Y;
    int AA = m_Perm[A] + a_Z;
 
    return Grad(m_Perm[AA], 1, 1, 1);
}