#include <LedControl.h>
LedControl lc = LedControl (11,13,10,3);
#define echoPin 3 // attach pin D2 Arduino to pin Echo of HC-SR04
#define trigPin 2 //attach pin D3 Arduino to pin Trig of HC-SR04 // defines variables
int duration; // variable for the duration of sound wave travel
int distance;//variable for the distance measurement
byte dot[8]= {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};

void setup()
{
  lc.shutdown(0,false); //sets up 8x8 matrix
	lc.setIntensity(0,50); // Set brightness to a medium value
	lc.clearDisplay(0); // Clear the display
	pinMode(trigPin, OUTPUT); // Sets the trigPin as an OUTPUT
	pinMode(echoPin, INPUT); // Sets the echoPin as an INPUT
}

void printByte(byte character [], int panel) {
  int i = 0;
  for (i = 0; i < 8; i++) {
    lc.setRow(panel, i, character[i]);
  }
}

void loop()
{
  int panel; // which panel to us
  //byte red[8]= {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
  int value = analogRead(A0); // read of potentiometer value
  int scale = map(value, 0, 1023, 0, 17); // 16 rows, plus one
  digitalWrite(trigPin, LOW);
	delayMicroseconds(2);// Sets the trigPin HIGH (ACTIVE) for 10 microseconds
	digitalWrite(trigPin, HIGH);
	delayMicroseconds(10); //Creates a ten microsecond delay
	digitalWrite(trigPin, LOW); // Reads the echoPin, returns the sound wave travel time in microseconds

	duration = pulseIn(echoPin, HIGH);// Calculating the distance
	distance = duration * 0.034 / 2; // Speed of sound wave divided by 2 (go and back)
  /*if (distance > 200)
  {
  panel = 0;
	int scale = map(distance, 0 , 400, 0, 8);  // Mapping 0 to 400CM with 0 to 8 rows
	for (int i=0;i<8;i++){
		if (i<= scale){
			dot[i] = 0xff;
      
		}
		else{
			dot[i] = 0x00;
      
		}
	}
  }*/

  if (value > 512) { // if raw potentiometer is above middle, use panel 0, subtract 8 for row 
    panel = 0;
    scale = scale - 8;
  } else { // if raw potentiometer is below middle, use panel 1, subtract row from 8
    panel = 1;
    scale = 8 - scale;
  }
  for (int j = 0; j < scale; j++) {
    dot[j] = 0xff;
  }
  printByte(dot, panel);
  //printByte(red, panel);
	delay(100);
}