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@atuline
Created Apr 18, 2019
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FastLED RGBW with gamma correction and Perlin noise
/* FastLED RGBW with gamma correction over Perlin Noise
*
* By: Andrew Tuline
*
* Date: March, 2019
*
* Example sketch using FastLED for RGBW strips (SK6812) along with gamma correction.
*
* The RGBW component was written by David Madison and originally by Jim Bumgardner.
*/
#include "FastLED.h"
const uint8_t PROGMEM gamma8[] = {
// 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // Change these two lines from '0' to '1' below
// 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2,
2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5,
5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 9, 9, 9, 10,
10, 10, 11, 11, 11, 12, 12, 13, 13, 13, 14, 14, 15, 15, 16, 16,
17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22, 23, 24, 24, 25,
25, 26, 27, 27, 28, 29, 29, 30, 31, 32, 32, 33, 34, 35, 35, 36,
37, 38, 39, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 50,
51, 52, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 66, 67, 68,
69, 70, 72, 73, 74, 75, 77, 78, 79, 81, 82, 83, 85, 86, 87, 89,
90, 92, 93, 95, 96, 98, 99,101,102,104,105,107,109,110,112,114,
115,117,119,120,122,124,126,127,129,131,133,135,137,138,140,142,
144,146,148,150,152,154,156,158,160,162,164,167,169,171,173,175,
177,180,182,184,186,189,191,193,196,198,200,203,205,208,210,213,
215,218,220,223,225,228,231,233,236,239,241,244,247,249,252,255 };
/* FastLED_RGBW
*
* Hack to enable SK6812 RGBW strips to work with FastLED.
*
* Original code by Jim Bumgardner (http://krazydad.com).
* Modified by David Madison (http://partsnotincluded.com).
*
*/
struct CRGBW {
union {
struct {
union {
uint8_t g;
uint8_t green;
};
union {
uint8_t r;
uint8_t red;
};
union {
uint8_t b;
uint8_t blue;
};
union {
uint8_t w;
uint8_t white;
};
};
uint8_t raw[4];
};
CRGBW(){}
CRGBW(uint8_t rd, uint8_t grn, uint8_t blu, uint8_t wht){
r = rd;
g = grn;
b = blu;
w = wht;
}
inline void operator = (const CRGB c) __attribute__((always_inline)){
this->r = c.r;
this->g = c.g;
this->b = c.b;
this->white = 0;
}
};
inline uint16_t getRGBWsize(uint16_t nleds){
uint16_t nbytes = nleds * 4;
if(nbytes % 3 > 0) return nbytes / 3 + 1;
else return nbytes / 3;
}
#define NUM_LEDS 30
#define DATA_PIN 12
CRGBW leds[NUM_LEDS];
CRGB *ledsRGB = (CRGB *) &leds[0];
const uint8_t max_bright = 255;
uint8_t highval = 0;
uint8_t lowval = 255;
long dist; // A random number for our noise generator.
uint16_t xscale = 500; // Wouldn't recommend changing this on the fly, or the animation will be really blocky.
uint16_t yscale = 500; // Wouldn't recommend changing this on the fly, or the animation will be really blocky.
void setup() {
Serial.begin(57600);
delay(1000); // Slow power up delay.
FastLED.addLeds<WS2812B, DATA_PIN, RGB>(ledsRGB, getRGBWsize(NUM_LEDS));
FastLED.setBrightness(max_bright);
set_max_power_in_volts_and_milliamps(5, 500); // FastLED Power management set at 5V, 500mA.
} // setup()
void loop(){
fillnoise8();
FastLED.show();
} // loop()
void fillnoise8() {
for(int i = 0; i < NUM_LEDS; i++) { // Just ONE loop to fill up the LED array as all of the pixels change.
uint8_t index = inoise8(i*xscale-dist, dist+i*yscale) % 255; // Get a value from the noise function. I'm using both x and y axis.
index = constrain(index, 42, 186);
index = map(index,42, 186,1,255);
if(index <lowval) lowval = index; // Use this to get an idea as to the range of the NOISE function.
if(index >highval) highval = index;
uint8_t results = pgm_read_byte(&gamma8[index]); // That sinewave is now corrected via the lookup table, which is quick, but consumes flash.
leds[i] = CRGBW(0,0,0,results); // or results*results/255
Serial.print(results); Serial.print(" "); Serial.print(lowval); Serial.print(" "); Serial.println(highval);
}
dist = millis()/16;
// dist += beatsin8(10,1,4); // Moving along the distance (that random number we started out with). Vary it a bit with a sine wave.
// In some sketches, I've used millis() instead of an incremented counter. Works great.
} // fillnoise8()
@jsonpoindexter

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@jsonpoindexter jsonpoindexter commented Apr 28, 2020

I just wanted to let you know I love you contributions to the LED community. Thank you!

@atuline

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Owner Author

@atuline atuline commented Apr 28, 2020

I just wanted to let you know I love you contributions to the LED community. Thank you!
Thanks very much. It's been a real fun hobby these past several years.

@soundmasteraj

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@soundmasteraj soundmasteraj commented Mar 10, 2021

Thank you as well, this has helped immensely! Much appreciated!

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