outputShiftString.ino

// helper function for mode-array
void outputShiftString() {
  char text[] = TEXT;
  outputShiftString(text);
}

//Shifts string through matrix
void outputShiftString(char * text){
  char *t;
  static int i = 0;
  static int xOffset = 0;
  static int yOffset = 0;
  static bool fistrun = true;

  /* iterate over text characters
   * loop takes car of two characters a the same time
  */

  if (countdown == 0){
    //remember last drawn char
    t = text;
    t = t + i;

    // if first character start from left side
    if (fistrun){
      xOffset=7;
      fistrun=false;
    }
    // draw char
    displayCharacterOffset(ASCII[(int)*t],xOffset,yOffset);
    
    // *********second charcter part***********
    if (xOffset < 0) {
      displayCharacterOffset(ASCII[(int)*(t+1)],xOffset+8,yOffset);
    }
    
    countdown = TEXT_SHIFT_SPEED_MS;
    
    //reset if end of string
    if(*t == '\0'){
      i = 0;     
      //xOffset=0;   
      fistrun = true;  
    }
    // if charachter shift completed
    if(xOffset <= -8){
      xOffset=0;
      i++;
    }
    //set X offset for next cycle
    xOffset--;
  }
}