twist pattern

// twist pattern
//fastled 16x16 matrix demo
//Yaroslaw Turbin 21.08.2020

#include "FastLED.h"

// Matrix size
#define NUM_ROWS 16
#define NUM_COLS 16

// LEDs pin
#define DATA_PIN 3

// LED brightness
#define BRIGHTNESS 255

#define NUM_LEDS NUM_ROWS * NUM_COLS

// Define the array of leds
CRGB leds[NUM_LEDS];
   byte hue =0;

void setup() {
  FastLED.addLeds<NEOPIXEL, DATA_PIN>(leds, NUM_LEDS);
  FastLED.setBrightness(BRIGHTNESS);
}

void loop() {



  for (uint8_t i = 0; i < NUM_COLS; i+=4)    {
    for (uint8_t j = 0; j < NUM_ROWS; j+=4) {

    patt1 (i,j, 128+hue+j*2, hue+i*2);
    patt2 (i+2,j, 128+hue+j*2,hue+i*2);
    patt2 (i,j+2, 128+hue+j*2,hue+i*2);
    patt1 (i+2,j+2, 128+hue+j*2,hue+i*2);

    }}

  FastLED.delay(10);
  hue +=1;
}



uint16_t XY (uint8_t x, uint8_t y) { return (y * NUM_COLS + x);}


void patt1 (uint8_t i, uint8_t j, uint8_t color1, uint8_t color2  ) {
  //  leds[XY (i, j)] =  CHSV (0, 255, 0); //color of background
    leds[XY (i+1, j)] =  CHSV (color1, 255, BRIGHTNESS);
    leds[XY (i+1, j+1)] =  CHSV (color1, 255, BRIGHTNESS);
    leds[XY (i, j+1)] =  CHSV (color2, 255, BRIGHTNESS);
}

void patt2 (uint8_t i, uint8_t j, uint8_t color1, uint8_t color2) {
 //   leds[XY (i, j)] =  CHSV (0, 255, 0);  //color of background
    leds[XY (i+1, j)] =  CHSV (color1, 255, BRIGHTNESS);
    leds[XY (i+1, j+1)] =  CHSV (color2, 255, BRIGHTNESS);
    leds[XY (i, j+1)] =  CHSV (color2, 255, BRIGHTNESS);
}