//Менять 126 вместо 255  //Perlin noise fire procedure    
//reddit.com/r/FastLED/comments/hgu16i/my_fire_effect_implementation_based_on_perlin
//idea ti make perlin noise with time offset X and Z coord 
//this automatic scroll fire pattern   and distort fire noise.
//then substract Y based coord value to shift fire color (not brightness) in palette. 
//fadeout color from bottom matrix to up.
//need some palette tweak for good looking fire color
#include "FastLED.h"
#define NUM_ROWS 16
#define NUM_COLS 16
#define NUM_LEDS NUM_ROWS * NUM_COLS
#define DATA_PIN 3
#define BRIGHTNESS 255
CRGB leds[NUM_LEDS];  // array of leds
 
DEFINE_GRADIENT_PALETTE(firepal) {// fire palette,  firepal - что за тип?
   0,     0,  0,   0,   //black
  32,   255,  0,   0,   // red
  190,  255, 255,  0,  //yellow
  255,  255, 255, 255  // white
};  
CRGBPalette16 myPal = firepal;  
void setup() {
  FastLED.addLeds<NEOPIXEL, DATA_PIN>(leds, NUM_LEDS);
  FastLED.setBrightness(BRIGHTNESS);
} 
void loop() { //Огонь   abs8(), qsub8 ()    8-bit
 int  a = millis();
 for(int i=0; i < NUM_COLS; i++) {
   for(int j=0; j < NUM_ROWS; j++) {                //960 max
   leds[XY(i,j)]=ColorFromPalette(myPal, qsub8(inoise8(i*60,j*60+a,a/3), 
    abs8(j-(NUM_ROWS-1))*255/(NUM_ROWS-1)),BRIGHTNESS);    
      }                                                              
  }
  FastLED.delay(5);    // что это?
} 
uint8_t XY(uint8_t x, uint8_t y) { return (y * NUM_COLS + x);}     
//or generate XY function for your matrix there:
//https://macetech.github.io/FastLED-XY-Map-Generator/