#include <FastLED.h>
#define TIMING 0
#define LED_PIN 3
#define NUM_LEDS 1630
#define LED_TYPE WS2812
#define COLOR_ORDER GRB
CRGB leds[NUM_LEDS];
const uint8_t led_count[] = {160, 145, 142, 135, 125, 118, 110, 102, 95, 86, 78, 70, 62, 53, 45, 37, 29, 21, 12, 4, 1};
#define NUM_RINGS (sizeof(led_count) / sizeof(led_count[0]))
#define FIRE_WIDTH 64
#define FIRE_HEIGHT NUM_RINGS
static uint8_t heat[FIRE_WIDTH][FIRE_HEIGHT];
CRGBPalette256 currentPalette;
void setup() {
Serial.begin(115200);
FastLED.addLeds<LED_TYPE, LED_PIN, COLOR_ORDER>(leds, NUM_LEDS);
uint8_t i = 0;
do {
currentPalette[i] = HeatColor(i);
} while (++i);
}
void loop() {
unsigned long t1 = micros();
Fire2012(random8() / 2 + 128);
unsigned long t2 = micros();
CRGB *led = leds;
uint8_t ring = 0;
// map the modified Fire2012() onto the rings
do {
uint8_t count = led_count[ring];
uint16_t td = FIRE_WIDTH * 255 / count;
uint16_t t = 0;
for (uint8_t i = 0; i < count ; i++) {
uint8_t h = heat[t >> 8][FIRE_HEIGHT - 1 - ring];
*led++ = currentPalette[h];
t += td;
}
} while (++ring < NUM_RINGS);
unsigned long t3 = micros();
FastLED.show();
if (TIMING) {
static unsigned long t2_sum, t3_sum;
t2_sum += t2 - t1;
t3_sum += t3 - t2;
static byte frame;
if (!(++frame % 64)) {
Serial.print(F("fire "));
Serial.print(t2_sum / 64);
Serial.print(F("us\tmap "));
Serial.print(t3_sum / 64);
Serial.print(F(" us\t"));
Serial.println(FastLED.getFPS());
t2_sum = t3_sum = 0;
}
}
}
void Fire2012(uint8_t activity) {
for (uint8_t h = 0; h < FIRE_WIDTH; h++) {
// Step 1. Cool down every cell a little
for( uint8_t i = 1; i < FIRE_HEIGHT - 1; i++) {
heat[h][i] = qsub8( heat[h][i], random8(32));
}
// Step 2. Heat from each cell drifts 'up' and diffuses a little
for( uint8_t k = FIRE_HEIGHT - 1; k >= 1; k--) {
uint8_t hleft = (h + FIRE_WIDTH - 1) % FIRE_WIDTH;
uint8_t hright = (h+1) % FIRE_WIDTH;
heat[h][k] = (heat[h][k]
+ heat[hleft][k - 1]
+ heat[h][k - 1]
+ heat[hright][k - 1] ) / 4;
}
if( random8() < activity ) {
heat[h][0] = qadd8( heat[h][0], random8(64));
} else {
heat[h][0] = qsub8( heat[h][0], random8(64));
}
}
}