#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

// Canvas size
const int a = 128;
const int b = 64;
const int reset = -1;
int info,x=0,y=b,oldstate1=0,oldstate2=0;
// Create display
Adafruit_SSD1306 display(a, b, &Wire, reset);

void setup() {
  Serial.begin(115200);
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println("SSD1306 allocation failed");
    for (;;)
      ;  // Don't proceed, loop forever
  }
  display.display();
  delay(500);
  display.clearDisplay();
  delay(200);
}
void display_text(String text, int u, int v) {
  display.setTextSize(1);       // Normal 1:1 pixel scale
  display.setTextColor(WHITE);  // Draw white text
  display.setCursor(u, v);      // Start at top-left corner
  display.println(text);
  display.display();
}
/*
void draw_fill(int xx,int yy,int widt,int heit){
  display.fillRect(xx,yy,widt,heit,WHITE);
}*/
void loop() {
  //display.clearDisplay();
  Serial.println(info);
  info=analogRead(A0)/8;
  //display_text("Filled rectangle..",0,5);
  display_text("Graphical wave...",0,5);
  if(info!=oldstate1){oldstate1=info;
     if(x>125){x=0;display.clearDisplay();}
     if(info>oldstate2){oldstate2=info;
        x++;y--;
        display.drawPixel(x,y,WHITE);
        display.display();
     }
     else if(info<oldstate2){oldstate2=info;
       x++;y++;
       display.drawPixel(x,y,WHITE);
       display.display();
       }}
}