Sinelon with multiple list pixels

sinelon_pixels

/* sinelon_pixels 
 *  
 *  Moves multiple pixels back and forth using waves of one form or another.
 *  
 *
 * By: Mark Kriegsman
 *
 * Modified by: Andrew Tuline
 *
 * Date: January 2018
 *
 * This uses the built in beat in FastLED to move one or more pixels back and forth.
 * 
 * Method 1, usies beatsin8() is a nice smooth sinewave.
 * Method 2, uses triwave8() which is a triangle wave.
 * Method 3 counts the pixels up and down. Oh wait, I didn't include method 3 because I REALLY don't want to add a bunch of 'if' statements and use elementary school arithmetic to count pixels up and down. Ugh!
 * 
 * Note that triwave8() isn't as easy to use as beatsin8. Sad panda.
 *
 */


#include "FastLED.h"                                          // FastLED library. Preferably the latest copy of FastLED 2.1.

#if FASTLED_VERSION < 3001000
#error "Requires FastLED 3.1 or later; check github for latest code."
#endif 

// Fixed definitions cannot change on the fly.
#define LED_DT 12                                             // Data pin to connect to the strip.
#define LED_CK 11                                             // Clock pin for WS2801 or APA102.
#define COLOR_ORDER BGR                                       // It's GRB for WS2812 and BGR for APA102.
#define LED_TYPE APA102                                       // Using APA102, WS2812, WS2801. Don't forget to modify LEDS.addLeds to suit.
#define NUM_LEDS 40                                           // Number of LED's.

// Global variables can be changed on the fly.
uint8_t max_bright = 128;                                      // Overall brightness definition. It can be changed on the fly.

struct CRGB leds[NUM_LEDS];                                    // Initialize our LED array.

CRGBPalette16 currentPalette;
CRGBPalette16 targetPalette;
TBlendType    currentBlending;                                // NOBLEND or LINEARBLEND


// Define variables used by the sequences.

#define ledlen 3                                              // Number of LED's to move back and forth.

uint8_t thisbeat =  10;                                        // Beats per minute for first part of dot.
uint8_t thisfade =   240;                                     // How quickly does it fade? Lower = slower fade rate.
uint8_t  thissat = 255;                                       // The saturation, where 255 = brilliant colours.
uint8_t  thisbri = 255;                                       // Brightness of a sequence.
uint8_t    myhue =   0;                                       // Hue, or palette index #.

int    thisdelay = 10;



void setup() {
  
  Serial.begin(57600);                                        // Initialize serial port for debugging.
  delay(1000);                                                // Soft startup to ease the flow of electrons.

//  LEDS.addLeds<LED_TYPE, LED_DT, COLOR_ORDER>(leds, NUM_LEDS);        // Use this for WS2812B
  LEDS.addLeds<LED_TYPE, LED_DT, LED_CK, COLOR_ORDER>(leds, NUM_LEDS);  // Use this for WS2801 or APA102

  currentBlending = LINEARBLEND;
  currentPalette = PartyColors_p;
  
  FastLED.setBrightness(max_bright);
  set_max_power_in_volts_and_milliamps(5, 500);                     // FastLED Power management set at 5V, 500mA.
  
} // setup()



void loop () {

  EVERY_N_MILLISECONDS(thisdelay) {                                 // FastLED based non-blocking delay to update/display the sequence.
    sinelon_pixels();                                               // Call our sequence.
  }

  FastLED.show();

} // loop()



void sinelon_pixels() {                                             // a colored dot sweeping back and forth, with fading trails
  
  fadeToBlackBy( leds, NUM_LEDS, thisfade);
  
  int pos1 = beatsin8(thisbeat,0,NUM_LEDS-ledlen);                  // This is METHOD 1. 

  int pos2 = triwave8(millis()/20);                                 // Which goes from 0 to 255.                                                            
  pos2 = (pos2*(NUM_LEDS-ledlen+1))/255;                            // We need to map that go go to NUM_LEDS-ledlen
   

  for(int i=0; i<ledlen; i++)
    leds[(i+pos2)%(NUM_LEDS)] = ColorFromPalette(currentPalette, myhue, thisbri, currentBlending);    // Try both the pos1 and pos2 variables!! Add the modulo operator for safety.

} // sinelon_pixels()