a pattern for an infinity mirror cleaned up and no longer requires first color to be CRGB::Black

color_bar_chase.ino

#include <FastLED.h>

#define NUM_LEDS 30
#define DATA_PIN 6

int FrameDelay = 100;
int colorBarPosition = 1;
int frameCounter = 0;

//list of colors these are RGB hex colors
long colorPallet[] = {
	CRGB::Blue,
	CRGB::OrangeRed,
	CRGB::Purple,
	CRGB::Yellow,
	CRGB::Red,
	CRGB::Green,
	CRGB::DeepPink,
	CRGB::DarkCyan,
	
};

// calculate number of colors in the array, needed later
int numberofColors=(sizeof(colorPallet)/sizeof(colorPallet[0]));
// calculate color bar length based on number of leds
int colorBarLength = (NUM_LEDS/numberofColors)*4;
int palletPosition = 0;
bool clearLEDS = false;

// setup LED array
CRGBArray<NUM_LEDS> leds;

void setup()
{
	delay(3000); // sanity delay for recovery if needed
	FastLED.addLeds<WS2812B, DATA_PIN, GRB>(leds, NUM_LEDS);
	FastLED.clear();
	FastLED.setBrightness (128);
	FastLED.show();
}

void loop()
{
	EVERY_N_MILLISECONDS(FrameDelay)
	{
		// loop to shift LED values lower the array
		for (int x=0; x<NUM_LEDS-1; x++)
		{
			leds[x] = leds[x+1];
		}
		
		// set last LED to the correct color based on color bar position and color bar length
		if ((colorBarPosition <= colorBarLength) && !clearLEDS)
		{
			leds[NUM_LEDS-1] = colorPallet[palletPosition];
			colorBarPosition++;
		}
		
		// check pallet position and bar position if at the end of both, start clear process
		if ((palletPosition == numberofColors-1) && (colorBarPosition > colorBarLength) && !clearLEDS)
		{
			//set last LED to black(0x000000)
			leds[NUM_LEDS-1]=CRGB::Black;
			// reset variables to start for bar positions
			palletPosition = 0;
			colorBarPosition = 1;
			//set clear LEDS flag to complete clearing
			clearLEDS= true;
			
		}
		if ((colorBarPosition > colorBarLength) && !clearLEDS)
		{
			// reset bar position and step to next color
			colorBarPosition = 1;
			palletPosition = palletPosition+1;
		}
		// check if clearing process is complete, if so clear flag
		if (clearLEDS && !leds(0,NUM_LEDS-1))
		{
			clearLEDS = false;
		}
	}

	FastLED.show ();
	
}

I updated this file to make it easier to adapt to other projects.

I also eliminated the need to have CRGB::Black as the first color in the color pallet.

Hi
I am working with the above code. It is working fine.
But I couldn't understand how the pixels shift from last LED

for (int x=0; x<NUM_LEDS-1; x++)
{
leds[x] = leds[x+1];
}

Also please explain quoted above what it does?

Thanks in advance

I just noticed this question.

It copies the value of leds[x+1] to leds[x] for each led in the array.

each line below is a single loop of the for loop
leds[1] copied to leds[0]
leds[2] copied to leds[1]
leds[3] copied to leds[2]
...
leds[NUM_LEDS-1] copied to leds[NUM_LEDS-2]

Does this help?