#include "U8glib.h"
U8GLIB_SSD1306_128X64 u8g(U8G_I2C_OPT_NONE|U8G_I2C_OPT_DEV_0);  // I2C / TWI
const int SCREEN_WIDTH = 128;
const int SCREEN_HEIGHT = 64;
float radius = min(SCREEN_HEIGHT, SCREEN_WIDTH) / 2 - 1;

const int X_CENTER = SCREEN_WIDTH / 2;
const int Y_CENTER = SCREEN_HEIGHT / 2;

void draw(void) {
  // Increase OLED brightness
  u8g.setContrast(255); // Set the OLED brightness to maximum

  // Draw 4 concentric circles with a common center
  for (int i = 0; i < 4; i++) {
    u8g.drawCircle(X_CENTER, Y_CENTER, radius - (i * 10));
  }

  // Print "Modified by Arvind" in the empty space of OLED
  u8g.setFont(u8g_font_chikita);
  //u8g.drawStr(0, 50, "Modified ");
  delay(800);
  u8g.drawStr(0, 60, "by Arvind");
   delay(800);
  u8g.drawStr(0, 10, "concentric");
   delay(800);
  u8g.drawStr(0, 20, "circles");
  delay(800);
}

void setup(void) {
  // flip screen, if required
  // u8g.setRot180();
}

void loop(void) {
 
  u8g.firstPage();
  do {
    draw();
  } while (u8g.nextPage());

  // Rebuild the picture after some delay
  delay(500);
}