Led[] ledCube = new Led[64];

// detection tollerance for mouse hovering led
int tollerance = 5;
float ledPosArray[][]; // coordinates of leds on screen (see method for use)
int cubeSize = 150;

// widht and height of window
int wWidth = 640;
int wHeight = 480;

// scene center
int cx = wWidth/2;
int cy = wHeight/2;
int cz = -cubeSize/2;

// camera positions
float camEyeX = 0;
float camEyeY = 0;
float camEyeZ = 0;
float viewX = 0;
float viewY = 0;
float viewZ = 0;
float camUpX = 0;
float camUpY = 1;
float camUpZ = 0;

// Polar coordinates for camera
float theta = 0;      
float phi = 90;       
float rho = 300;   //distance from cam to point of view

void setup(){
  int c = 0; // counter = number of leds
  ledPosArray = new float[64][2]; // init screen coordinates array
  for (int i = 0; i < 4; i++) {
    for (int j = 0; j < 4; j++) {
      for (int k = 0; k < 4; k++) {
        ledCube[c] = new Led(j,-i,-k, false, 120, col, i+1);
        c++;
      }
    }
  }
  size(wWidth,wHeight, P3D);
}

void draw(){
  background(0);
  pointLight(150,255,255,200,200,200);
  noLights();
  noStroke();
  noSmooth();
  fill(160);
  drawAxis(); // debug
  updateCamPosition();
  camera(camEyeX,camEyeY,camEyeZ,viewX,viewY,viewZ,camUpX,camUpY,camUpZ);
  translate(-(cubeSize / 2), (cubeSize / 2), (cubeSize / 2));
  updateArray(); // update coordinates of spheres on screen for mouse hover detection
  box(8); // debug : identifies start point for the construction of the cube
  drawCube();
}

// One Led (sphere) of the cube and its properties
class Led {
  int x;
  int y;
  int z;
  boolean isOn; // true when led is lit
  boolean isHover = false; // true when mouse hover
  color ledColor;
  int activeCol; // columns 1 to 16 (in dev, not used yet)
  int activePlan; // number of cube active plan where the Led belongs (1 low level to 4 high level) (in dev, not used yet)

// constructor
  Led (int xPos, int yPos, int zPos, boolean state, color col, int column, int line) {
    x = xPos;
    y = yPos;
    z = zPos;
    isOn = state; // Led On/Off
    ledColor = col;
    activeCol = column; // position of LED in cube (x and z axis) (in dev, not used yet)
    activePlan = line; // position of LED in cube (plane = y axis) (in dev, not used yet)
  }
  
// Led display method  
  void display() {
    pushMatrix();
    translate(x * (cubeSize / 3), y * (cubeSize / 3), z * (cubeSize / 3));
    if (isOn) 
    {
      fill(color(0,0,255));
    }
    else if (isHover)
    {
      fill(color(255,0,0));
    }
    else 
    {
      fill(color(166,166,166));
    }
    box(4);
    popMatrix();
  }
}

// for debug : draw axis x (green), y (blue) and z (red)
void drawAxis(){
  stroke(0,255,0);
  line(0,0,0,100,0,0);
  stroke(0,0,255);
  line(0,0,0,0,100,0);
  stroke(255,0,0);
  line(0,0,0,0,0,-100);
  noStroke();
}

// draw cube with spheres
void drawCube() {
   for (int i = 0; i < 64; i++) {
    ledCube[i].display();
  } 
}

// calculate x and y screen : list[led_number][coordinates] with coordinates = 0 (x) and 1 (y)
void updateArray(){
 for (int i = 0; i < 64; i++) {
   ledPosArray[i][0] = (int)screenX(ledCube[i].x,ledCube[i].y,ledCube[i].z); 
   ledPosArray[i][1] = (int)screenY(ledCube[i].x,ledCube[i].y,ledCube[i].z); 
 } 
}

// update position of camera moved with mouse click and drag
void updateCamPosition(){
    camEyeX = rho * cos(radians(theta)) * cos(radians(phi));
    camEyeY = rho * sin(radians(theta));
    camEyeZ = rho * cos(radians(theta)) * sin(radians(phi));
    
      //Prevent flipping if camera moves past top or bottom of cube
      if ((theta > 90.0 && theta < 270.0) || (theta < -90.0 && theta > -270.0))
    {
      camUpY = -1.0;
    }
    else
    {
      camUpY = 1.0;
    }
}

// colorize spheres when mouse hover or selected
void mousePressed()
{
  for (int i=0 ; i < 64 ; i++) {
  if (ledCube[i].isHover && !ledCube[i].isOn) ledCube[i].isOn = true;
  else if (ledCube[i].isHover && ledCube[i].isOn) ledCube[i].isOn = false;
  }

}

// rotate camera whith mouse click and drag
void mouseDragged(){
  if (mouseButton == LEFT){
    theta = theta + (pmouseY - mouseY);
    phi = phi - (pmouseX - mouseX);
  }
  if (mouseButton == RIGHT){
    rho = rho - (pmouseY - mouseY);    
  }
}

// detects mouse hover and change state
void mouseMoved()
{
  for (int i=0 ; i < 64 ; i++)
  {
    if (mouseX >= ledPosArray[i][0] - tollerance && mouseX <= ledPosArray[i][0] + tollerance && mouseY >= ledPosArray[i][1] - tollerance && mouseY <= ledPosArray[i][1] + tollerance)
    //if (mouseX >= ledCube[i].x - tollerance && mouseX <= ledCube[i].x + tollerance && mouseY >= ledCube[i].y + tollerance && mouseY <= ledCube[i].y - tollerance)
    {
      ledCube[i].isHover = true;
    }
    else
      ledCube[i].isHover = false;
  }
}