#include "FastLED.h"
#define DATA_PIN 4
#define BRIGHTNESS 255
#define NUM_LEDS 256
#define LED_COLS 16
#define LED_ROWS 16
#define LED_TYPE    WS2812B
#define COLOR_ORDER GRB
CRGB leds[NUM_LEDS];
//#define FRAMES_PER_SECOND 60
const uint8_t kMatrixWidth = 16;
const uint8_t kMatrixHeight = 16;

const bool    kMatrixSerpentineLayout = false;


void setup() {
  FastLED.addLeds<LED_TYPE,DATA_PIN,COLOR_ORDER>(leds, NUM_LEDS); //setCorrection(TypicalLEDStrip);
  //FastLED.addLeds<LED_TYPE,DATA_PIN,CLK_PIN,COLOR_ORDER>(leds, NUM_LEDS).setCorrection(TypicalLEDStrip);
  FastLED.setBrightness(BRIGHTNESS);
 //Serial.begin(115200);
}

void loop() 
{
   float t=millis()/250.0;
 
  for (int i = 0; i < LED_COLS; i++) { 
  for (int j = 0; j < LED_ROWS; j++) {
    byte ind = sin8(i*8+sin8(i*2+6*t))/2+sin8(j*8+sin8(j*2+t*7)/2);
  //  byte ind = sin8(i*16*sin(PI*j/32+t)+j*8*cos(2*PI*i/32+t*2))>>1;
  //  byte ind = sin8(i*j)/2-sin8(i*8+t)/2+sin8(i*i+j*j+t)/2;
  //  byte ind = sin8((i<<4)+t)/2+sin8((j<<4)+t)/2;

    leds [XY(i,j)] = CHSV (ind,255,255);
  }
  }
      FastLED.show();

}
 
uint16_t XY( uint8_t x, uint8_t y)
{
  uint16_t i;
  if( kMatrixSerpentineLayout == false) {
    i = (y * kMatrixWidth) + x;
  }
  if( kMatrixSerpentineLayout == true) {
    if( y & 0x01) {
      // Odd rows run backwards
      uint8_t reverseX = (kMatrixWidth - 1) - x;
      i = (y * kMatrixWidth) + reverseX;
    } else {
      // Even rows run forwards
      i = (y * kMatrixWidth) + x;
    }
  }
  return i;
}