// Adafruit_NeoMatrix example for single NeoPixel Shield.
// Scrolls 'Howdy' across the matrix in a portrait (vertical) orientation.

#include <Adafruit_GFX.h>
#include <Adafruit_NeoMatrix.h>
#include <Adafruit_NeoPixel.h>
#ifndef PSTR
 #define PSTR // Make Arduino Due happy
#endif

#define PIN 2

// MATRIX DECLARATION:
// Parameter 1 = width of NeoPixel matrix
// Parameter 2 = height of matrix
// Parameter 3 = pin number (most are valid)
// Parameter 4 = matrix layout flags, add together as needed:
//   NEO_MATRIX_TOP, NEO_MATRIX_BOTTOM, NEO_MATRIX_LEFT, NEO_MATRIX_RIGHT:
//     Position of the FIRST LED in the matrix; pick two, e.g.
//     NEO_MATRIX_TOP + NEO_MATRIX_LEFT for the top-left corner.
//   NEO_MATRIX_ROWS, NEO_MATRIX_COLUMNS: LEDs are arranged in horizontal
//     rows or in vertical columns, respectively; pick one or the other.
//   NEO_MATRIX_PROGRESSIVE, NEO_MATRIX_ZIGZAG: all rows/columns proceed
//     in the same order, or alternate lines reverse direction; pick one.
//   See example below for these values in action.
// Parameter 5 = pixel type flags, add together as needed:
//   NEO_KHZ800  800 KHz bitstream (most NeoPixel products w/WS2812 LEDs)
//   NEO_KHZ400  400 KHz (classic 'v1' (not v2) FLORA pixels, WS2811 drivers)
//   NEO_GRB     Pixels are wired for GRB bitstream (most NeoPixel products)
//   NEO_GRBW    Pixels are wired for GRBW bitstream (RGB+W NeoPixel products)
//   NEO_RGB     Pixels are wired for RGB bitstream (v1 FLORA pixels, not v2)


// Example for NeoPixel Shield.  In this application we'd like to use it
// as a 5x8 tall matrix, with the USB port positioned at the top of the
// Arduino.  When held that way, the first pixel is at the top right, and
// lines are arranged in columns, progressive order.  The shield uses
// 800 KHz (v2) pixels that expect GRB color data.
Adafruit_NeoMatrix matrix = Adafruit_NeoMatrix(16, 16, PIN,
  NEO_MATRIX_TOP     + NEO_MATRIX_RIGHT +
  NEO_MATRIX_COLUMNS + NEO_MATRIX_PROGRESSIVE,
  NEO_GRB            + NEO_KHZ800);


int16_t x = matrix.width();
uint8_t color_index = 0;
char text[] = "ARVIND PATIL";
int scroll_limit = sizeof(text) * 6; // each text character is 6 pixels wide

void setup() {
  matrix.begin();
  matrix.setTextWrap(false);
  matrix.setBrightness(240);
  matrix.setTextColor(matrix.Color(255, 0, 0)); // default color is red
}

void loop() {
  matrix.fillScreen(0);
  matrix.setCursor(x, 0);
  matrix.print(text);

  if(--x < -scroll_limit) {
    x = matrix.width();
    color_index = 0; // reset the rainbow color index
  }
  matrix.setTextColor(color_wheel(color_index));
  color_index += max(1, 256 / scroll_limit);
  matrix.show();
  delay(100);
}

uint16_t color_wheel(uint8_t pos) {
  pos = 255 - pos;
  if(pos < 85) {
//  return ((uint32_t)(255 - pos * 3) << 16) | ((uint32_t)(0) << 8) | (pos * 3);
    return matrix.Color((uint16_t)(255 - pos * 3), 0, (pos * 3));
  } else if(pos < 170) {
    pos -= 85;
//  return ((uint32_t)(0) << 16) | ((uint32_t)(pos * 3) << 8) | (255 - pos * 3);
    return matrix.Color(0, (uint32_t)(pos * 3), (255 - pos * 3));
  } else {
    pos -= 170;
//  return ((uint32_t)(pos * 3) << 16) | ((uint32_t)(255 - pos * 3) << 8) | (0);
    return matrix.Color((uint16_t)(pos * 3), (uint32_t)(255 - pos * 3), 0);
  }
}