Question about Scroll Display Left

Projects Programming
5

This is what I came up with. I modified another users sketch that I had.
You will need to change a few things to get it to work on your screen. Also it would be better if this was made into a class.

#include <Wire.h> 
#include <LiquidCrystal_I2C.h>
#define N_CHARS  ((sizeof(Compass)/sizeof(Compass[0]))-1)

LiquidCrystal_I2C lcd(0x20,20,4);  // set the LCD address to 0x20 for a 16 chars and 2 line display

char Compass[21] = {
  "N....E....S....W...."};
  
int index = 19, index2 = 0;
unsigned long time = 0, time2 = 0;

void setup()
{
  lcd.init();                      // initialize the lcd  
  lcd.backlight();
}

void loop() 
{
  setHeadingRight(0, 1000);
  setHeadingLeft(1, 500);
}

void setHeadingRight(byte row, unsigned long duration) 
{
  if(millis() - time > duration)
  {
    time = millis();
    if(index >= 0)
    { 
      index--;
      for (int i = 0; i < N_CHARS; i++) 
      {
        lcd.setCursor(i,row);
        if(index == N_CHARS) index = 0;
        lcd.print(Compass[index++]);	
      }
    }
    else index = 19;
  }
}

void setHeadingLeft(byte row, unsigned long duration2) 
{
  if(millis() - time2 > duration2)
  {
    time2 = millis();
    if(index2 < 20) 
    {
      index2++;
      for (int i = 0; i < N_CHARS; i++) 
      {
        lcd.setCursor(i,row);
        if(index2 == N_CHARS) index2 = 0;
        lcd.print(Compass[index2++]);	
      }
    }
    else index2 = 0;
  }
}