// Bellicose Birds code by Chris Orban

float Q = 0; //initial value
float I = 0; //initial value

float Vcap;
float C = 0.375;

float Vbatt = 10; // Volts

float R = 5; // Ohms

float dt = 0.1;

boolean battery_is_connected = false;

DPGraph graph1 = new DPGraph();
DPGraph graph2 = new DPGraph();

PImage imgConnected;
PImage imgDisconnected;

void setup() {
  size(750,500);
  smooth();

  Q = 0;
  I = 0;
  
  graph1.colorFunction = color(255,177,100); //orange
  graph1.xTitle = "time";

  graph2.colorFunction = color(0,191,191); //aqua

  imgDisconnected = loadImage("http://www.physics.ohio-state.edu/~orban/physics1251lab_2016/RCdisconnected.png");
  imgConnected = loadImage("http://www.physics.ohio-state.edu/~orban/physics1251lab_2016/RCconnected.png");
}

// For people with C and C++ experience, draw() is
// very similar to main(), except that draw() 
// is run over and over again 
void draw() {
  
  if (keyPressed) {
   if (key == 'c') battery_is_connected = true;
   if (key == 'd') battery_is_connected = false;
  }
  
  if ( battery_is_connected == true) {
    I = 0; 
    Vcap = Vbatt;
    Q = C*Vcap;
  } else { // battery is not connected
    I = Vcap/R;
    Q += -I*dt;
    Vcap = Q/C;
  }
  
  // This will clear the screen and re-draw it
  display();

  graph1.addPoint(Q);
  graph1.display();
  //println("Q = ",Q); // Uncomment if curious about precise value of Q
  
  graph2.addPoint(I);
  graph2.display();
  //println("I = ",I); // Uncomment if curious about precise value of I

} // end draw()