neopixel bus multipin output using buffer blt layoutmap

npbexample.ino

// test parallel output on multiple pins on ESP32 using RMT technique against RGB fans (ws2812b leds)
// 8 channels (pins) are possible with this ESP32 RMT method.

#include <NeoPixelBus.h>
#include <arduino.h>

// manually configure these params:
const uint16_t strip01_PixelCount = 18;
const uint8_t strip01_PixelPin = 2;

const uint16_t strip02_PixelCount = 18;
const uint8_t strip02_PixelPin = 13;

// calculate total pixel count for use later:
const uint16_t totalPixelCount = strip01_PixelCount + strip02_PixelCount;


// these are the "output" objects, but we'll use a "buffer" to collect the led color info, then assign peices of the buffer to these real pins:
NeoPixelBus<NeoGrbFeature, NeoEsp32Rmt0Ws2812xMethod> strip01(strip01_PixelCount, strip01_PixelPin);
NeoPixelBus<NeoGrbFeature, NeoEsp32Rmt1Ws2812xMethod> strip02(strip02_PixelCount, strip02_PixelPin);

// create the "input" LED array to store the LED data, use the "buffer" method so the LEDs array can be used later:
// wants    name, width, height, pixels
//
//  The buffer is a bitmap. so it has a height, width. Our use case is a single "strip" of leds put together by WLED
//  so the width of this bitmap really represents our total pixel count:
//
NeoBuffer<NeoBufferMethod<NeoGrbFeature>> strip00(totalPixelCount,1,NULL);

#define colorSaturation 128

RgbColor red(colorSaturation, 0, 0);
RgbColor green(0, colorSaturation, 0);
RgbColor blue(0, 0, colorSaturation);
RgbColor white(colorSaturation);
RgbColor black(0);

HslColor hslRed(red);
HslColor hslGreen(green);
HslColor hslBlue(blue);
HslColor hslWhite(white);
HslColor hslBlack(black);

// create a new layout map for later use to move the buffer pixels out to NeoPixelBus objects
// in our case, width is equal to total pixel count, and height is 1, since its not a panel.

// create a "NeoTopology" object, named "topo" that defines a qty to fill into. 
// This is measured in pixels, so the first entry is "1", instead of "0" as used the coordinate system.
NeoTopology<RowMajorLayout> topo(totalPixelCount, 1);


uint16_t LayoutMap(int16_t x, int16_t y)
{
  return topo.MapProbe(x, y);
}

void setup()
{

    // required init:
    strip01.Begin();
    strip02.Begin();

    // reset them to off:
    strip01.Show();
    strip02.Show();

    // set the entire buffer to black color to set off for all pixels:
    strip00.ClearTo(black);

}

void loop()
{

// assign color to the buffer object LEDs instead: (notice the x/y coordiinate, just use 0 since we're using a "single row" bitmap)
    strip00.SetPixelColor(35,0, red);
    strip00.SetPixelColor(34,0, red);
    strip00.SetPixelColor(33,0, red);
    strip00.SetPixelColor(32,0, red);
    strip00.SetPixelColor(31,0, red);
    strip00.SetPixelColor(30,0, red);
    strip00.SetPixelColor(29,0, white);
    strip00.SetPixelColor(28,0, white);
    strip00.SetPixelColor(27,0, white);
    strip00.SetPixelColor(26,0, white);
    strip00.SetPixelColor(25,0, white);
    strip00.SetPixelColor(24,0, white);
    strip00.SetPixelColor(23,0, green);
    strip00.SetPixelColor(22,0, green);
    strip00.SetPixelColor(21,0, green);
    strip00.SetPixelColor(20,0, green);
    strip00.SetPixelColor(19,0, green);
    strip00.SetPixelColor(18,0, green);

    strip00.SetPixelColor(17,0, red);
    strip00.SetPixelColor(16,0, green);
    strip00.SetPixelColor(15,0, blue);
    strip00.SetPixelColor(14,0, white);
    strip00.SetPixelColor(13,0, red);
    strip00.SetPixelColor(12,0, green);
    strip00.SetPixelColor(11,0, blue);
    strip00.SetPixelColor(10,0, white);
    strip00.SetPixelColor(9,0, red);
    strip00.SetPixelColor(8,0, green);
    strip00.SetPixelColor(7,0, blue);
    strip00.SetPixelColor(6,0, white);
    strip00.SetPixelColor(5,0, red);
    strip00.SetPixelColor(4,0, green);
    strip00.SetPixelColor(3,0, blue);
    strip00.SetPixelColor(2,0, white);
    strip00.SetPixelColor(1,0, red);
    strip00.SetPixelColor(0,0, green);


    // now we need to divy out the pixels from the buffer (NeoBuffer object) to the actual strips (NeoPixelBus objects)

    // use the more complicated form of the Blt method:  https://github.com/Makuna/NeoPixelBus/wiki/NeoBuffer-object

    // send pixels from strip00 using Blt, to strip01, starting at buffer index 0,0 (width,height coordinate of starting pixel), to strip01's starting coordinate 0,0, consisting of: 18 pixels wide, 1 pixel tall.
    // using the LayoutMap
    strip00.Blt(strip01, 0, 0, 0, 0, strip01_PixelCount, 1, LayoutMap);

    // send pixels from strip00 using Blt, to strip02, starting at buffer index 18,0 (width,height coordinate of starting pixel), to strip01's starting coordinate 0,0 consisting of: 18 pixels wide, 1 pixel tall, using the layoutmap.
    strip00.Blt(strip02, 18, 0, 0, 0, 18, 1, LayoutMap);

    strip01.Show();
    strip02.Show();

    delay(2000);

}