// simple project with rotating 3D cube using Arduino UNO and Transparent 128x64 OLED Display, 
// created by upir, 2022
// youtube channel: https://www.youtube.com/upir_upir
// full tutoral is here: https://youtu.be/kBAcaA7NAlA

// Turbo pressure gauge tutorial: https://youtu.be/JXmw1xOlBdk
// Transparent OLED tutorial: https://youtu.be/hIFDcksXgBk
// Knob + OLED tutorial: https://youtu.be/NPfaLKKsf_Q

// useful links:
// u8g documentation: https://github.com/olikraus/u8glib/wiki/userreference
// Wokwi starting project: https://wokwi.com/arduino/projects/300867986768527882
// Arduino UNO: http://store.arduino.cc/products/arduino-uno-rev3
// Arduino UNO MINI: https://store.arduino.cc/products/uno-mini-le
// Multidimensional arrays: https://www.tutorialspoint.com/arduino/arduino_multi_dimensional_arrays.htm
// 2D Rotation: https://en.wikipedia.org/wiki/Rotation_(mathematics)
// Normal OLED Display: https://www.aliexpress.com/item/4001051535838.html
// Transparent OLED Display: https://a.aliexpress.com/_mKGmhKg
// Big OLED Display: https://www.aliexpress.com/item/1005003091769556.html
// Arduino breadboard prototyping shield: https://www.adafruit.com/product/2077



#include "U8glib.h" // u8g library, note there is a newer version u8g2, please use the older one

#define VERT_PIN A0
#define HORZ_PIN A1
#define SEL_PIN  2

// uncomment the correct connection - fast I2C, slow I2C, SPI
U8GLIB_SSD1306_128X64 u8g(U8G_I2C_OPT_DEV_0 | U8G_I2C_OPT_NO_ACK | U8G_I2C_OPT_FAST); // Fast I2C / TWI
//U8GLIB_SSD1306_128X64 u8g(U8G_I2C_OPT_DEV_0 | U8G_I2C_OPT_NO_ACK); // slow I2C / TWI     -- I had to use "slow I2C" in my case
//U8GLIB_SSD1306_128X64 u8g(13, 11, 8, 9, 10); // SPI connection  - SCL = 13, SDA = 11, RES = 10, DC = 9, CS = 8

int points[8][2]; // eight 2D points for the cube, values will be calculated in the code

int orig_points [8][3] = {  // eight 3D points - set values for 3D cube
{-1,-1, 1},
{1,-1,1},
{1,1,1},
{-1,1,1},
{-1,-1,-1},
{1,-1,-1},
{1,1,-1},
{-1,1,-1}
};

int orig_points_tri [4][3] = {
{-1,-1,-1},
{-1,1,-1},
{1,1,-1},
{-1,-1,1} //{0,0,1}
};

int orig_points_tri2 [4][3] = {
{1,-0.866,0},
{-0.5,-0.866,0.866},
{-0.5,-0.866,-0.866},
{1,0.5482,0}
};

int var = 1;
int p;
bool once;

float rotated_3d_points [8][3];   // eight 3D points - rotated around Y axis
float Zrotated_3d_points [8][3];  // eight 3D points - rotated around Z axis
float angle_deg = 60.0;           // rotation around the Y axis
float angle_user1 = 0;
float z_offset = -4;            // offset on Z axis
float cube_size = 70.0;           // cube size (multiplier)
//float time_frame;               // ever increasing time value

void setup() {

  Serial.begin(9600);

  u8g.setColorIndex(1); // set color to white

  pinMode(VERT_PIN, INPUT);
  pinMode(HORZ_PIN, INPUT);
  pinMode(SEL_PIN, INPUT_PULLUP);
}

void loop() {

  int horz = analogRead(HORZ_PIN);                   // HORZ_PIN goes from 0 (right) to 1023 (left)
  int vert = analogRead(VERT_PIN);                   // VERT_PIN goes from 0 (bottom) to 1023 (top)
  bool selPressed = digitalRead(SEL_PIN) == LOW;     // selPressed is true is the joystick is pressed
  

  horz = map(horz, 0, 1023, 0, 200);     // horz goes from 0 (right) to 200 (left)
  vert = map(vert, 0, 1023, 0, 200);     // vert goes from 0 (bottom) to 200 (top)

  //Serial.print("horz = ");
  //Serial.println(horz);

  if (horz > 150) {
    angle_user1 = -5;
  }
  else if (120 < horz && horz < 150 ) {
    angle_user1 = -2;
  }
  else if (50 < horz && horz < 80){
    angle_user1 = 2;
  }
  else if (horz < 50){
    angle_user1 = 5;
  }
  else {
    angle_user1 = 0;
  }
  

  // increase the angle by 5° increments
  if (angle_deg < 360) {
    angle_deg = angle_deg + angle_user1;
  } else {
    angle_deg = 0;
  }


  if (selPressed && !once){
    var += 1;
    if (var > 2){
      var = 1;
    }
    once = true;
  }

  if (!selPressed) {
    once = false;
  }

  switch (var) {
  case 1:

    // calculate the points
  for (int i=0; i<8; i++) {
    // rotate 3d points around the Y axis (rotating X nad Z positions)
    rotated_3d_points [i][0] = orig_points [i][0] * cos(radians(angle_deg)) - orig_points [i][2] * sin(radians(angle_deg));
    rotated_3d_points [i][1] = orig_points [i][1];
    rotated_3d_points [i][2] = orig_points [i][0] * sin(radians(angle_deg)) + orig_points [i][2] * cos(radians(angle_deg)) + z_offset;  

    // rotate 3d points around the Z axis (rotating X and Y positions)
    Zrotated_3d_points [i][0] = rotated_3d_points [i][0] * cos(radians(angle_deg)) - rotated_3d_points [i][1] * sin(radians(angle_deg));
    Zrotated_3d_points [i][1] = rotated_3d_points [i][0] * sin(radians(angle_deg)) + rotated_3d_points [i][1] * cos(radians(angle_deg));
    Zrotated_3d_points [i][2] = rotated_3d_points [i][2] ;

    // project 3d points into 2d space with perspective divide -- 2D x = x/z,   2D y = y/z
    points[i][0] = round(64 + rotated_3d_points [i][0] / rotated_3d_points [i][2] * cube_size);
    points[i][1] = round(32 + rotated_3d_points [i][1] / rotated_3d_points [i][2] * cube_size);    
  }


  u8g.firstPage();
  do {
      // connect the lines between the individual points
      u8g.drawLine(points[ 0 ][ 0 ], points[ 0 ][ 1 ] , points[ 1 ][ 0 ] , points[ 1 ][ 1 ] );  // connect points 0-1
      u8g.drawLine(points[ 1 ][ 0 ], points[ 1 ][ 1 ] , points[ 2 ][ 0 ] , points[ 2 ][ 1 ] );  // connect points 1-2  
      u8g.drawLine(points[ 2 ][ 0 ], points[ 2 ][ 1 ] , points[ 3 ][ 0 ] , points[ 3 ][ 1 ] );  // connect points 2-3      
      u8g.drawLine(points[ 3 ][ 0 ], points[ 3 ][ 1 ] , points[ 0 ][ 0 ] , points[ 0 ][ 1 ] );  // connect points 3-0      

      u8g.drawLine(points[ 4 ][ 0 ], points[ 4 ][ 1 ] , points[ 5 ][ 0 ] , points[ 5 ][ 1 ] );  // connect points 4-5
      u8g.drawLine(points[ 5 ][ 0 ], points[ 5 ][ 1 ] , points[ 6 ][ 0 ] , points[ 6 ][ 1 ] );  // connect points 5-6  
      u8g.drawLine(points[ 6 ][ 0 ], points[ 6 ][ 1 ] , points[ 7 ][ 0 ] , points[ 7 ][ 1 ] );  // connect points 6-7      
      u8g.drawLine(points[ 7 ][ 0 ], points[ 7 ][ 1 ] , points[ 4 ][ 0 ] , points[ 4 ][ 1 ] );  // connect points 7-4  

      u8g.drawLine(points[ 0 ][ 0 ], points[ 0 ][ 1 ] , points[ 4 ][ 0 ] , points[ 4 ][ 1 ] );  // connect points 0-4
      u8g.drawLine(points[ 1 ][ 0 ], points[ 1 ][ 1 ] , points[ 5 ][ 0 ] , points[ 5 ][ 1 ] );  // connect points 1-5  
      u8g.drawLine(points[ 2 ][ 0 ], points[ 2 ][ 1 ] , points[ 6 ][ 0 ] , points[ 6 ][ 1 ] );  // connect points 2-6      
      u8g.drawLine(points[ 3 ][ 0 ], points[ 3 ][ 1 ] , points[ 7 ][ 0 ] , points[ 7 ][ 1 ] );  // connect points 3-7                 


  } while ( u8g.nextPage() );   // u8g library specific, has to be there
    break;

  case 2:
   // calculate the points
  for (int i=0; i<4; i++) {
    // rotate 3d points around the Y axis (rotating X nad Z positions)
    rotated_3d_points [i][0] = orig_points_tri [i][0] * cos(radians(angle_deg)) - orig_points_tri [i][2] * sin(radians(angle_deg));
    rotated_3d_points [i][1] = orig_points_tri [i][1];
    rotated_3d_points [i][2] = orig_points_tri [i][0] * sin(radians(angle_deg)) + orig_points_tri [i][2] * cos(radians(angle_deg)) + z_offset;  

    // rotate 3d points around the Z axis (rotating X and Y positions)
    Zrotated_3d_points [i][0] = orig_points_tri2 [i][0] * cos(radians(angle_deg)) - orig_points_tri2 [i][1] * sin(radians(angle_deg));
    Zrotated_3d_points [i][1] = orig_points_tri2 [i][0] * sin(radians(angle_deg)) + orig_points_tri2 [i][1] * cos(radians(angle_deg));
    Zrotated_3d_points [i][2] = orig_points_tri2 [i][2] + z_offset;

    // project 3d points into 2d space with perspective divide -- 2D x = x/z,   2D y = y/z
    points[i][0] = round(64 + rotated_3d_points [i][0] / rotated_3d_points [i][2] * cube_size);
    points[i][1] = round(32 + rotated_3d_points [i][1] / rotated_3d_points [i][2] * cube_size);    
  }

  u8g.firstPage();
  do {
      // connect the lines between the individual points
      u8g.drawLine(points[ 0 ][ 0 ], points[ 0 ][ 1 ] , points[ 1 ][ 0 ] , points[ 1 ][ 1 ] );  // connect points 0-1
      u8g.drawLine(points[ 1 ][ 0 ], points[ 1 ][ 1 ] , points[ 2 ][ 0 ] , points[ 2 ][ 1 ] );  // connect points 1-2  
      u8g.drawLine(points[ 2 ][ 0 ], points[ 2 ][ 1 ] , points[ 0 ][ 0 ] , points[ 0 ][ 1 ] );  // connect points 2-0   

      u8g.drawLine(points[ 0 ][ 0 ], points[ 0 ][ 1 ] , points[ 3 ][ 0 ] , points[ 3 ][ 1 ] );  // connect points 0-3      
      u8g.drawLine(points[ 3 ][ 0 ], points[ 3 ][ 1 ] , points[ 1 ][ 0 ] , points[ 1 ][ 1 ] );  // connect points 3-1

      u8g.drawLine(points[ 3 ][ 0 ], points[ 3 ][ 1 ] , points[ 2 ][ 0 ] , points[ 2 ][ 1 ] );  // connect points 3-2                 


  } while ( u8g.nextPage() );   // u8g library specific, has to be there
    break;

  default:

    break;
}

  

}