noise.cpp

#define FASTLED_INTERNAL
#include "FastLED.h"

FASTLED_NAMESPACE_BEGIN

#define P(x) FL_PGM_READ_BYTE_NEAR(p + x)

FL_PROGMEM static uint8_t const p[] = { 151,160,137,91,90,15,
   131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,
   190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,
   88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166,
   77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,
   102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196,
   135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123,
   5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,
   223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9,
   129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228,
   251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107,
   49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,
   138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180,151
   };


#if FASTLED_NOISE_ALLOW_AVERAGE_TO_OVERFLOW == 1
#define AVG15(U,V) (((U)+(V)) >> 1)
#else
// See if we should use the inlined avg15 for AVR with MUL instruction
#if defined(__AVR__) && (LIB8_ATTINY == 0)
#define AVG15(U,V) (avg15_inline_avr_mul((U),(V)))
// inlined copy of avg15 for AVR with MUL instruction; cloned from math8.h
// Forcing this inline in the 3-D 16bit noise produces a 12% speedup overall,
// at a cost of just +8 bytes of net code size.
static int16_t inline __attribute__((always_inline))  avg15_inline_avr_mul( int16_t i, int16_t j)
{
    asm volatile(
                 /* first divide j by 2, throwing away lowest bit */
                 "asr %B[j]          \n\t"
                 "ror %A[j]          \n\t"
                 /* now divide i by 2, with lowest bit going into C */
                 "asr %B[i]          \n\t"
                 "ror %A[i]          \n\t"
                 /* add j + C to i */
                 "adc %A[i], %A[j]   \n\t"
                 "adc %B[i], %B[j]   \n\t"
                 : [i] "+a" (i)
                 : [j] "a"  (j) );
    return i;
}
#else
#define AVG15(U,V) (avg15((U),(V)))
#endif
#endif

//
// #define FADE_12
#define FADE_16

#ifdef FADE_12
#define FADE logfade12
#define LERP(a,b,u) lerp15by12(a,b,u)
#else
#define FADE(x) scale16(x,x)
#define LERP(a,b,u) lerp15by16(a,b,u)
#endif
static int16_t inline __attribute__((always_inline))  grad16(uint8_t hash, int16_t x, int16_t y, int16_t z) {
#if 0
  switch(hash & 0xF) {
    case  0: return (( x) + ( y))>>1;
    case  1: return ((-x) + ( y))>>1;
    case  2: return (( x) + (-y))>>1;
    case  3: return ((-x) + (-y))>>1;
    case  4: return (( x) + ( z))>>1;
    case  5: return ((-x) + ( z))>>1;
    case  6: return (( x) + (-z))>>1;
    case  7: return ((-x) + (-z))>>1;
    case  8: return (( y) + ( z))>>1;
    case  9: return ((-y) + ( z))>>1;
    case 10: return (( y) + (-z))>>1;
    case 11: return ((-y) + (-z))>>1;
    case 12: return (( y) + ( x))>>1;
    case 13: return ((-y) + ( z))>>1;
    case 14: return (( y) + (-x))>>1;
    case 15: return ((-y) + (-z))>>1;
  }
#else
  hash = hash&15;
  int16_t u = hash<8?x:y;
  int16_t v = hash<4?y:hash==12||hash==14?x:z;
  if(hash&1) { u = -u; }
  if(hash&2) { v = -v; }

  return AVG15(u,v);
#endif
}

static int16_t inline __attribute__((always_inline)) grad16(uint8_t hash, int16_t x, int16_t y) {
  hash = hash & 7;
  int16_t u,v;
  if(hash < 4) { u = x; v = y; } else { u = y; v = x; }
  if(hash&1) { u = -u; }
  if(hash&2) { v = -v; }

  return AVG15(u,v);
}

static int16_t inline __attribute__((always_inline)) grad16(uint8_t hash, int16_t x) {
  hash = hash & 15;
  int16_t u,v;
  if(hash > 8) { u=x;v=x; }
  else if(hash < 4) { u=x;v=1; }
  else { u=1;v=x; }
  if(hash&1) { u = -u; }
  if(hash&2) { v = -v; }

  return AVG15(u,v);
}

// selectBasedOnHashBit performs this:
//   result = (hash & (1<<bitnumber)) ? a : b
// but with an AVR asm version that's smaller and quicker than C
// (and probably not worth including in lib8tion)
static int8_t inline __attribute__((always_inline)) selectBasedOnHashBit(uint8_t hash, uint8_t bitnumber, int8_t a, int8_t b) {
    int8_t result;
#if !defined(__AVR__)
    result = (hash & (1<<bitnumber)) ? a : b;
#else
    asm volatile(
        "mov %[result],%[a]          \n\t"
        "sbrs %[hash],%[bitnumber]   \n\t"
        "mov %[result],%[b]          \n\t"
        : [result] "=r" (result)
        : [hash] "r" (hash),
          [bitnumber] "M" (bitnumber),
          [a] "r" (a),
          [b] "r" (b)
        );
#endif
    return result;
}

static int8_t  inline __attribute__((always_inline)) grad8(uint8_t hash, int8_t x, int8_t y, int8_t z) {
#if 0
  switch(hash & 0xF) {
    case  0: return (( x) + ( y))>>1;
    case  1: return ((-x) + ( y))>>1;
    case  2: return (( x) + (-y))>>1;
    case  3: return ((-x) + (-y))>>1;
    case  4: return (( x) + ( z))>>1;
    case  5: return ((-x) + ( z))>>1;
    case  6: return (( x) + (-z))>>1;
    case  7: return ((-x) + (-z))>>1;
    case  8: return (( y) + ( z))>>1;
    case  9: return ((-y) + ( z))>>1;
    case 10: return (( y) + (-z))>>1;
    case 11: return ((-y) + (-z))>>1;
    case 12: return (( y) + ( x))>>1;
    case 13: return ((-y) + ( z))>>1;
    case 14: return (( y) + (-x))>>1;
    case 15: return ((-y) + (-z))>>1;
  }
#else

  hash &= 0xF;

  int8_t u, v;
  //u = (hash&8)?y:x;
  u = selectBasedOnHashBit( hash, 3, y, x);

#if 1
  v = hash<4?y:hash==12||hash==14?x:z;
#else
  // Verbose version for analysis; generates idenitical code.
  if( hash < 4) { // 00 01 02 03
      v = y;
  } else {
      if( hash==12 || hash==14) { // 0C 0E
          v = x;
      } else {
          v = z; // 04 05 06 07   08 09 0A 0B   0D  0F
      }
  }
#endif

  if(hash&1) { u = -u; }
  if(hash&2) { v = -v; }

  return avg7(u,v);
#endif
}

static int8_t inline __attribute__((always_inline)) grad8(uint8_t hash, int8_t x, int8_t y)
{
  // since the tests below can be done bit-wise on the bottom
  // three bits, there's no need to mask off the higher bits
  //  hash = hash & 7;

  int8_t u,v;
  if( hash & 4) {
      u = y; v = x;
  } else {
      u = x; v = y;
  }

  if(hash&1) { u = -u; }
  if(hash&2) { v = -v; }

  return avg7(u,v);
}

static int8_t inline __attribute__((always_inline)) grad8(uint8_t hash, int8_t x)
{
  // since the tests below can be done bit-wise on the bottom
  // four bits, there's no need to mask off the higher bits
  //    hash = hash & 15;

  int8_t u,v;
  if(hash & 8) {
      u=x; v=x;
  } else {
    if(hash & 4) {
        u=1; v=x;
    } else {
        u=x; v=1;
    }
  }

  if(hash&1) { u = -u; }
  if(hash&2) { v = -v; }

  return avg7(u,v);
}


#ifdef FADE_12
uint16_t logfade12(uint16_t val) {
  return scale16(val,val)>>4;
}

static int16_t inline __attribute__((always_inline)) lerp15by12( int16_t a, int16_t b, fract16 frac)
{
   //if(1) return (lerp(frac,a,b));
    int16_t result;
    if( b > a) {
        uint16_t delta = b - a;
        uint16_t scaled = scale16(delta,frac<<4);
        result = a + scaled;
     } else {
        uint16_t delta = a - b;
        uint16_t scaled = scale16(delta,frac<<4);
      result = a - scaled;
     }
    return result;
}
#endif

static int8_t inline __attribute__((always_inline)) lerp7by8( int8_t a, int8_t b, fract8 frac)
{
    // int8_t delta = b - a;
    // int16_t prod = (uint16_t)delta * (uint16_t)frac;
    // int8_t scaled = prod >> 8;
    // int8_t result = a + scaled;
    // return result;
    int8_t result;
    if( b > a) {
        uint8_t delta = b - a;
        uint8_t scaled = scale8( delta, frac);
        result = a + scaled;
    } else {
        uint8_t delta = a - b;
        uint8_t scaled = scale8( delta, frac);
        result = a - scaled;
    }
    return result;
}

int16_t inoise16_raw(uint32_t x, uint32_t y, uint32_t z)
{
  // Find the unit cube containing the point
  uint8_t X = (x>>16)&0xFF;
  uint8_t Y = (y>>16)&0xFF;
  uint8_t Z = (z>>16)&0xFF;

  // Hash cube corner coordinates
  uint8_t A = P(X)+Y;
  uint8_t AA = P(A)+Z;
  uint8_t AB = P(A+1)+Z;
  uint8_t B = P(X+1)+Y;
  uint8_t BA = P(B) + Z;
  uint8_t BB = P(B+1)+Z;

  // Get the relative position of the point in the cube
  uint16_t u = x & 0xFFFF;
  uint16_t v = y & 0xFFFF;
  uint16_t w = z & 0xFFFF;

  // Get a signed version of the above for the grad function
  int16_t xx = (u >> 1) & 0x7FFF;
  int16_t yy = (v >> 1) & 0x7FFF;
  int16_t zz = (w >> 1) & 0x7FFF;
  uint16_t N = 0x8000L;

  u = FADE(u); v = FADE(v); w = FADE(w);


  // skip the log fade adjustment for the moment, otherwise here we would
  // adjust fade values for u,v,w
  int16_t X1 = LERP(grad16(P(AA), xx, yy, zz), grad16(P(BA), xx - N, yy, zz), u);
  int16_t X2 = LERP(grad16(P(AB), xx, yy-N, zz), grad16(P(BB), xx - N, yy - N, zz), u);
  int16_t X3 = LERP(grad16(P(AA+1), xx, yy, zz-N), grad16(P(BA+1), xx - N, yy, zz-N), u);
  int16_t X4 = LERP(grad16(P(AB+1), xx, yy-N, zz-N), grad16(P(BB+1), xx - N, yy - N, zz - N), u);

  int16_t Y1 = LERP(X1,X2,v);
  int16_t Y2 = LERP(X3,X4,v);

  int16_t ans = LERP(Y1,Y2,w);

  return ans;
}

uint16_t inoise16(uint32_t x, uint32_t y, uint32_t z) {
  int32_t ans = inoise16_raw(x,y,z);
  ans = ans + 19052L;
  uint32_t pan = ans;
  // pan = (ans * 220L) >> 7.  That's the same as:
  // pan = (ans * 440L) >> 8.  And this way avoids a 7X four-byte shift-loop on AVR.
  // Identical math, except for the highest bit, which we don't care about anyway,
  // since we're returning the 'middle' 16 out of a 32-bit value anyway.
  pan *= 440L;
  return (pan>>8);

  // // return scale16by8(pan,220)<<1;
  // return ((inoise16_raw(x,y,z)+19052)*220)>>7;
  // return scale16by8(inoise16_raw(x,y,z)+19052,220)<<1;
}

int16_t inoise16_raw(uint32_t x, uint32_t y)
{
  // Find the unit cube containing the point
  uint8_t X = x>>16;
  uint8_t Y = y>>16;

  // Hash cube corner coordinates
  uint8_t A = P(X)+Y;
  uint8_t AA = P(A);
  uint8_t AB = P(A+1);
  uint8_t B = P(X+1)+Y;
  uint8_t BA = P(B);
  uint8_t BB = P(B+1);

  // Get the relative position of the point in the cube
  uint16_t u = x & 0xFFFF;
  uint16_t v = y & 0xFFFF;

  // Get a signed version of the above for the grad function
  int16_t xx = (u >> 1) & 0x7FFF;
  int16_t yy = (v >> 1) & 0x7FFF;
  uint16_t N = 0x8000L;

  u = FADE(u); v = FADE(v);

  int16_t X1 = LERP(grad16(P(AA), xx, yy), grad16(P(BA), xx - N, yy), u);
  int16_t X2 = LERP(grad16(P(AB), xx, yy-N), grad16(P(BB), xx - N, yy - N), u);

  int16_t ans = LERP(X1,X2,v);

  return ans;
}

uint16_t inoise16(uint32_t x, uint32_t y) {
  int32_t ans = inoise16_raw(x,y);
  ans = ans + 17308L;
  uint32_t pan = ans;
  // pan = (ans * 242L) >> 7.  That's the same as:
  // pan = (ans * 484L) >> 8.  And this way avoids a 7X four-byte shift-loop on AVR.
  // Identical math, except for the highest bit, which we don't care about anyway,
  // since we're returning the 'middle' 16 out of a 32-bit value anyway.
  pan *= 484L;
  return (pan>>8);
    
  // return (uint32_t)(((int32_t)inoise16_raw(x,y)+(uint32_t)17308)*242)>>7;
  // return scale16by8(inoise16_raw(x,y)+17308,242)<<1;
}

int16_t inoise16_raw(uint32_t x)
{
  // Find the unit cube containing the point
  uint8_t X = x>>16;

  // Hash cube corner coordinates
  uint8_t A = P(X);
  uint8_t AA = P(A);
  uint8_t B = P(X+1);
  uint8_t BA = P(B);

  // Get the relative position of the point in the cube
  uint16_t u = x & 0xFFFF;

  // Get a signed version of the above for the grad function
  int16_t xx = (u >> 1) & 0x7FFF;
  uint16_t N = 0x8000L;

  u = FADE(u);

  int16_t ans = LERP(grad16(P(AA), xx), grad16(P(BA), xx - N), u);

  return ans;
}

uint16_t inoise16(uint32_t x) {
  return ((uint32_t)((int32_t)inoise16_raw(x) + 17308L)) << 1;
}

int8_t inoise8_raw(uint16_t x, uint16_t y, uint16_t z)
{
  // Find the unit cube containing the point
  uint8_t X = x>>8;
  uint8_t Y = y>>8;
  uint8_t Z = z>>8;

  // Hash cube corner coordinates
  uint8_t A = P(X)+Y;
  uint8_t AA = P(A)+Z;
  uint8_t AB = P(A+1)+Z;
  uint8_t B = P(X+1)+Y;
  uint8_t BA = P(B) + Z;
  uint8_t BB = P(B+1)+Z;

  // Get the relative position of the point in the cube
  uint8_t u = x;
  uint8_t v = y;
  uint8_t w = z;

  // Get a signed version of the above for the grad function
  int8_t xx = ((uint8_t)(x)>>1) & 0x7F;
  int8_t yy = ((uint8_t)(y)>>1) & 0x7F;
  int8_t zz = ((uint8_t)(z)>>1) & 0x7F;
  uint8_t N = 0x80;

  // u = FADE(u); v = FADE(v); w = FADE(w);
  u = scale8_LEAVING_R1_DIRTY(u,u); v = scale8_LEAVING_R1_DIRTY(v,v); w = scale8(w,w);

  int8_t X1 = lerp7by8(grad8(P(AA), xx, yy, zz), grad8(P(BA), xx - N, yy, zz), u);
  int8_t X2 = lerp7by8(grad8(P(AB), xx, yy-N, zz), grad8(P(BB), xx - N, yy - N, zz), u);
  int8_t X3 = lerp7by8(grad8(P(AA+1), xx, yy, zz-N), grad8(P(BA+1), xx - N, yy, zz-N), u);
  int8_t X4 = lerp7by8(grad8(P(AB+1), xx, yy-N, zz-N), grad8(P(BB+1), xx - N, yy - N, zz - N), u);

  int8_t Y1 = lerp7by8(X1,X2,v);
  int8_t Y2 = lerp7by8(X3,X4,v);

  int8_t ans = lerp7by8(Y1,Y2,w);

  return ans;
}

uint8_t inoise8(uint16_t x, uint16_t y, uint16_t z) {
  return scale8(76+(inoise8_raw(x,y,z)),215)<<1;
}

int8_t inoise8_raw(uint16_t x, uint16_t y)
{
  // Find the unit cube containing the point
  uint8_t X = x>>8;
  uint8_t Y = y>>8;

  // Hash cube corner coordinates
  uint8_t A = P(X)+Y;
  uint8_t AA = P(A);
  uint8_t AB = P(A+1);
  uint8_t B = P(X+1)+Y;
  uint8_t BA = P(B);
  uint8_t BB = P(B+1);

  // Get the relative position of the point in the cube
  uint8_t u = x;
  uint8_t v = y;

  // Get a signed version of the above for the grad function
  int8_t xx = ((uint8_t)(x)>>1) & 0x7F;
  int8_t yy = ((uint8_t)(y)>>1) & 0x7F;
  uint8_t N = 0x80;

  // u = FADE(u); v = FADE(v); w = FADE(w);
  u = scale8_LEAVING_R1_DIRTY(u,u); v = scale8(v,v);

  int8_t X1 = lerp7by8(grad8(P(AA), xx, yy), grad8(P(BA), xx - N, yy), u);
  int8_t X2 = lerp7by8(grad8(P(AB), xx, yy-N), grad8(P(BB), xx - N, yy - N), u);

  int8_t ans = lerp7by8(X1,X2,v);

  return ans;
  // return scale8((70+(ans)),234)<<1;
}

uint8_t inoise8(uint16_t x, uint16_t y) {
  return scale8(69+inoise8_raw(x,y),237)<<1;
}

int8_t inoise8_raw(uint16_t x)
{
  // Find the unit cube containing the point
  uint8_t X = x>>8;

  // Hash cube corner coordinates
  uint8_t A = P(X);
  uint8_t AA = P(A);
  uint8_t B = P(X+1);
  uint8_t BA = P(B);

  // Get the relative position of the point in the cube
  uint8_t u = x;

  // Get a signed version of the above for the grad function
  int8_t xx = ((uint8_t)(x)>>1) & 0x7F;
  uint8_t N = 0x80;

  u = scale8(u,u);

  int8_t ans = lerp7by8(grad8(P(AA), xx), grad8(P(BA), xx - N), u);

  return ans;
  // return scale8((70+(ans)),234)<<1;
}

uint8_t inoise8(uint16_t x) {
  return scale8(69+inoise8_raw(x), 255)<<1;
}

// struct q44 {
//   uint8_t i:4;
//   uint8_t f:4;
//   q44(uint8_t _i, uint8_t _f) {i=_i; f=_f; }
// };

// uint32_t mul44(uint32_t v, q44 mulby44) {
//     return (v *mulby44.i)  + ((v * mulby44.f) >> 4);
// }
//
// uint16_t mul44_16(uint16_t v, q44 mulby44) {
//     return (v *mulby44.i)  + ((v * mulby44.f) >> 4);
// }

void fill_raw_noise8(uint8_t *pData, uint8_t num_points, uint8_t octaves, uint16_t x, int scale, uint16_t time) {
  uint32_t _xx = x;
  uint32_t scx = scale;
  for(int o = 0; o < octaves; o++) {
    for(int i = 0,xx=_xx; i < num_points; i++, xx+=scx) {
          pData[i] = qadd8(pData[i],inoise8(xx,time)>>o);
    }

    _xx <<= 1;
    scx <<= 1;
  }
}

void fill_raw_noise16into8(uint8_t *pData, uint8_t num_points, uint8_t octaves, uint32_t x, int scale, uint32_t time) {
  uint32_t _xx = x;
  uint32_t scx = scale;
  for(int o = 0; o < octaves; o++) {
    for(int i = 0,xx=_xx; i < num_points; i++, xx+=scx) {
      uint32_t accum = (inoise16(xx,time))>>o;
      accum += (pData[i]<<8);
      if(accum > 65535) { accum = 65535; }
      pData[i] = accum>>8;
    }

    _xx <<= 1;
    scx <<= 1;
  }
}

void fill_raw_2dnoise8(uint8_t *pData, int width, int height, uint8_t octaves, q44 freq44, fract8 amplitude, int skip, uint16_t x, int scalex, uint16_t y, int scaley, uint16_t time) {
  if(octaves > 1) {
    fill_raw_2dnoise8(pData, width, height, octaves-1, freq44, amplitude, skip+1, x*freq44, freq44 * scalex, y*freq44, freq44 * scaley, time);
  } else {
    // amplitude is always 255 on the lowest level
    amplitude=255;
  }

  scalex *= skip;
  scaley *= skip;

  fract8 invamp = 255-amplitude;
  uint16_t xx = x;
  for(int i = 0; i < height; i++, y+=scaley) {
    uint8_t *pRow = pData + (i*width);
    xx = x;
    for(int j = 0; j < width; j++, xx+=scalex) {
      uint8_t noise_base = inoise8(xx,y,time);
      noise_base = (0x80 & noise_base) ? (noise_base - 127) : (127 - noise_base);
      noise_base = scale8(noise_base<<1,amplitude);
      if(skip == 1) {
        pRow[j] = scale8(pRow[j],invamp) + noise_base;
      } else {
        for(int ii = i; ii<(i+skip) && ii<height; ii++) {
          uint8_t *pRow = pData + (ii*width);
          for(int jj=j; jj<(j+skip) && jj<width; jj++) {
            pRow[jj] = scale8(pRow[jj],invamp) + noise_base;
          }
        }
      }
    }
  }
}

void fill_raw_2dnoise8(uint8_t *pData, int width, int height, uint8_t octaves, uint16_t x, int scalex, uint16_t y, int scaley, uint16_t time) {
  fill_raw_2dnoise8(pData, width, height, octaves, q44(2,0), 128, 1, x, scalex, y, scaley, time);
}

void fill_raw_2dnoise16(uint16_t *pData, int width, int height, uint8_t octaves, q88 freq88, fract16 amplitude, int skip, uint32_t x, int scalex, uint32_t y, int scaley, uint32_t time) {
  if(octaves > 1) {
    fill_raw_2dnoise16(pData, width, height, octaves-1, freq88, amplitude, skip, x *freq88 , scalex *freq88, y * freq88, scaley * freq88, time);
  } else {
    // amplitude is always 255 on the lowest level
    amplitude=65535;
  }

  scalex *= skip;
  scaley *= skip;
  fract16 invamp = 65535-amplitude;
  for(int i = 0; i < height; i+=skip, y+=scaley) {
    uint16_t *pRow = pData + (i*width);
    for(int j = 0,xx=x; j < width; j+=skip, xx+=scalex) {
      uint16_t noise_base = inoise16(xx,y,time);
      noise_base = (0x8000 & noise_base) ? noise_base - (32767) : 32767 - noise_base;
      noise_base = scale16(noise_base<<1, amplitude);
      if(skip==1) {
        pRow[j] = scale16(pRow[j],invamp) + noise_base;
      } else {
        for(int ii = i; ii<(i+skip) && ii<height; ii++) {
          uint16_t *pRow = pData + (ii*width);
          for(int jj=j; jj<(j+skip) && jj<width; jj++) {
            pRow[jj] = scale16(pRow[jj],invamp) + noise_base;
          }
        }
      }
    }
  }
}

int32_t nmin=11111110;
int32_t nmax=0;

void fill_raw_2dnoise16into8(uint8_t *pData, int width, int height, uint8_t octaves, q44 freq44, fract8 amplitude, int skip, uint32_t x, int scalex, uint32_t y, int scaley, uint32_t time) {
  if(octaves > 1) {
    fill_raw_2dnoise16into8(pData, width, height, octaves-1, freq44, amplitude, skip+1, x*freq44, scalex *freq44, y*freq44, scaley * freq44, time);
  } else {
    // amplitude is always 255 on the lowest level
    amplitude=255;
  }

  scalex *= skip;
  scaley *= skip;
  uint32_t xx;
  fract8 invamp = 255-amplitude;
  for(int i = 0; i < height; i+=skip, y+=scaley) {
    uint8_t *pRow = pData + (i*width);
    xx = x;
    for(int j = 0; j < width; j+=skip, xx+=scalex) {
      uint16_t noise_base = inoise16(xx,y,time);
      noise_base = (0x8000 & noise_base) ? noise_base - (32767) : 32767 - noise_base;
      noise_base = scale8(noise_base>>7,amplitude);
      if(skip==1) {
        pRow[j] = qadd8(scale8(pRow[j],invamp),noise_base);
      } else {
        for(int ii = i; ii<(i+skip) && ii<height; ii++) {
          uint8_t *pRow = pData + (ii*width);
          for(int jj=j; jj<(j+skip) && jj<width; jj++) {
            pRow[jj] = scale8(pRow[jj],invamp) + noise_base;
          }
        }
      }
    }
  }
}

void fill_raw_2dnoise16into8(uint8_t *pData, int width, int height, uint8_t octaves, uint32_t x, int scalex, uint32_t y, int scaley, uint32_t time) {
  fill_raw_2dnoise16into8(pData, width, height, octaves, q44(2,0), 171, 1, x, scalex, y, scaley, time);
}

void fill_noise8(CRGB *leds, int num_leds,
            uint8_t octaves, uint16_t x, int scale,
            uint8_t hue_octaves, uint16_t hue_x, int hue_scale,
            uint16_t time) {
  uint8_t V[num_leds];
  uint8_t H[num_leds];

  memset(V,0,num_leds);
  memset(H,0,num_leds);

  fill_raw_noise8(V,num_leds,octaves,x,scale,time);
  fill_raw_noise8(H,num_leds,hue_octaves,hue_x,hue_scale,time);

  for(int i = 0; i < num_leds; i++) {
    leds[i] = CHSV(H[i],255,V[i]);
  }
}

void fill_noise16(CRGB *leds, int num_leds,
            uint8_t octaves, uint16_t x, int scale,
            uint8_t hue_octaves, uint16_t hue_x, int hue_scale,
            uint16_t time, uint8_t hue_shift) {
  uint8_t V[num_leds];
  uint8_t H[num_leds];

  memset(V,0,num_leds);
  memset(H,0,num_leds);

  fill_raw_noise16into8(V,num_leds,octaves,x,scale,time);
  fill_raw_noise8(H,num_leds,hue_octaves,hue_x,hue_scale,time);

  for(int i = 0; i < num_leds; i++) {
    leds[i] = CHSV(H[i] + hue_shift,255,V[i]);
  }
}

void fill_2dnoise8(CRGB *leds, int width, int height, bool serpentine,
            uint8_t octaves, uint16_t x, int xscale, uint16_t y, int yscale, uint16_t time,
            uint8_t hue_octaves, uint16_t hue_x, int hue_xscale, uint16_t hue_y, uint16_t hue_yscale,uint16_t hue_time,bool blend) {
  uint8_t V[height][width];
  uint8_t H[height][width];

  memset(V,0,height*width);
  memset(H,0,height*width);

  fill_raw_2dnoise8((uint8_t*)V,width,height,octaves,x,xscale,y,yscale,time);
  fill_raw_2dnoise8((uint8_t*)H,width,height,hue_octaves,hue_x,hue_xscale,hue_y,hue_yscale,hue_time);

  int w1 = width-1;
  int h1 = height-1;
  for(int i = 0; i < height; i++) {
    int wb = i*width;
    for(int j = 0; j < width; j++) {
      CRGB led(CHSV(H[h1-i][w1-j],255,V[i][j]));

      int pos = j;
      if(serpentine && (i & 0x1)) {
        pos = w1-j;
      }

      if(blend) {
        leds[wb+pos] >>= 1; leds[wb+pos] += (led>>=1);
      } else {
        leds[wb+pos] = led;
      }
    }
  }
}

void fill_2dnoise16(CRGB *leds, int width, int height, bool serpentine,
            uint8_t octaves, uint32_t x, int xscale, uint32_t y, int yscale, uint32_t time,
            uint8_t hue_octaves, uint16_t hue_x, int hue_xscale, uint16_t hue_y, uint16_t hue_yscale,uint16_t hue_time, bool blend, uint16_t hue_shift) {
  uint8_t V[height][width];
  uint8_t H[height][width];

  memset(V,0,height*width);
  memset(H,0,height*width);

  fill_raw_2dnoise16into8((uint8_t*)V,width,height,octaves,q44(2,0),171,1,x,xscale,y,yscale,time);
  // fill_raw_2dnoise16into8((uint8_t*)V,width,height,octaves,x,xscale,y,yscale,time);
  // fill_raw_2dnoise8((uint8_t*)V,width,height,hue_octaves,x,xscale,y,yscale,time);
  fill_raw_2dnoise8((uint8_t*)H,width,height,hue_octaves,hue_x,hue_xscale,hue_y,hue_yscale,hue_time);


  int w1 = width-1;
  int h1 = height-1;
  hue_shift >>= 8;

  for(int i = 0; i < height; i++) {
    int wb = i*width;
    for(int j = 0; j < width; j++) {
      CRGB led(CHSV(hue_shift + (H[h1-i][w1-j]),196,V[i][j]));

      int pos = j;
      if(serpentine && (i & 0x1)) {
        pos = w1-j;
      }

      if(blend) {
        leds[wb+pos] >>= 1; leds[wb+pos] += (led>>=1);
      } else {
        leds[wb+pos] = led;
      }
    }
  }
}

FASTLED_NAMESPACE_END