The fact that PHPoC supports WebSocket really interests me. I can program web-based games on my IoT board .
So let the game begin.

I made a similar one using Arduino. Check it out here:

https://www.hackster.io/Homer/arduin...ck-game-cb1b30

Demonstration



This classic game may make some of us feel childhood nostalgia. The game-play is simple, try to avoid hitting opponent cars and get many scores as possible. The car can switch between 5 lanes, and there are 15 different speeds. As speed increases, cars will run faster, making the game more difficult.

Hardware components

PHPoC Blue × 1
[Catalex] Rotary Angle Sensor × 1
USB Wifi dongle × 1



Data Flow

PHPoC ---> Web browser

Players interact with the rotary angle sensor. The input signal value of rotary angle sensor is used to switch the car's position.
PHPoC reads the value from rotary angle sensor. The input ADC values are divided into 5 different levels. Switching between levels means changing the lane. Simply, if the input signal is switched to another level, PHPoC will update level to Web browser via WebSocket. Then, JavaScript function will update the position (lane) of the car. JavaScript program will continuously update the position of opponents and game speed as well.


Schematics

Connect pin GND, VCC, and SIG of rotary angle sensor to GND, 3.3V and AD0 of PHPoC, respectively.


Click image for larger version  Name:	rotary.jpg Views:	1 Size:	53.6 KB ID:	370




Source Code
Source code includes:

init.php : it's run when system boots and specifies which file is run next

PHP Code:
<?php

system
("php task0.php");

?>

task0.php: This file contains server side code. It is run in infinite loop to read the signal value from rotary angle sensor and send it to web browser via WebSocket.
PHP Code:
<?php

if(_SERVER("REQUEST_METHOD"))
   exit; 
// avoid php execution via http request

include "/lib/sd_340.php";
include 
"/lib/sn_tcp_ws.php";

adc_setup(00); // adc0, channel 0
ws_setup(0"game""text.phpoc");
$adc_min 2048.0 2.5*400;
$last_adc_in 0;
while(
1)
{
   if(
ws_state(0) == TCP_CONNECTED)
   {
      
$adc_in adc_in(030);
      if(
abs($adc_in $last_adc_in) > 5)
      {

         
$adc_5 = (int)floor((float)(($adc_in $adc_min) / 400));

         if (
$adc_5<0)
         {
            
$adc_5 =0;
         }
         else
         if (
$adc_5>4)
            {
               
$adc_5 =4;
            }

         
ws_write(0, (string)$adc_5 "\r\n");

         
$last_adc_in $adc_in;
      }
   }
}

?>

index.php: This file contains client side code.
PHP Code:
<!DOCTYPE html>
<html>
<head>
<title>PHPoC - Web-based Game</title>
<meta name="viewport" content="width=device-width, initial-scale=0.7, maximum-scale=0.7">
<style>
body { text-align: center; font-size: 15pt; font-family: Arial, Helvetica, sans-serif;}
h1 { font-weight: bold; font-size: 25pt; }
h2 { font-weight: bold; font-size: 15pt; }
button { font-weight: bold; font-size: 15pt; }
</style>
<script>


var cvs_width = 480, cvs_height = 400;

function object(x, y)
{
    this.x = x;
    this.y = y;
}

function racing_car(x, y)
{
   this.last_x = -1;
    this.x = x;
    this.y = y;
}

var ws = null;
var ctx = null;

var user_car = null;
var opponent_cars = null;
var sidelines = null;
var cur_score = null;


var level_up = null;
var cur_level   = null;
var speed_default = null;
var speed_delta   = null;
var updated_speed = null;
var updated_timer = null;
var is_crashed = null;
var is_not_finished = null;

var car_width = null;
var car_height = null;
var line_width = null;
var block_size = null;
var line_distance = null;
var rect_line_width = null;
var blink_times = null;


function init()
{

   cur_score = 0;

   level_up = 0;
   cur_level = 0;
   speed_default = 300;
   speed_delta = 20;
   updated_speed = get_speed();

   is_crashed = false;
   is_not_finished = true;  
   blink_times = 0;

   var width = window.innerWidth;
   var height = window.innerHeight;

   var ratio_x = (width - 250) / cvs_width;
   var ratio_y = (height - 250) / cvs_height;
   var ratio = (ratio_x < ratio_y) ? ratio_x : ratio_y;

   cvs_width *= ratio;
   cvs_height *= ratio;

   block_size = cvs_height/24;
   car_width = 3;
   car_height = 4;

   line_width = 2*ratio;
   line_distance = 3*ratio;
   rect_line_width = 1*ratio;


   var canvas = document.getElementById("remote");
   canvas.width = cvs_width;  
   canvas.height = cvs_height;
   ctx = canvas.getContext("2d");
   ctx.translate(100, 0);

   opponent_cars = [];
   for (var i = 0; i<3; i++)
   {
      opponent_cars.push(new object((Math.floor(Math.random() * 5))*car_width, -(8+2*Math.floor(Math.random()))));
      opponent_cars.push(new object((Math.floor(Math.random() * 5))*car_width, -(24+2*Math.floor(Math.random()))));
   }

   sidelines = [];

   for (var i = 0; i<7; i++)
   {
      sidelines.push(new object(-2, 4*i));
      sidelines.push(new object(16, 4*i));
   }      

   user_car = new racing_car(2*car_width, 20);

   draw_car(user_car, false);
   draw_sideline();
   draw_grid();

}

function connect_onclick()
{
   if(ws == null)
   {
      var ws_host_addr = "<?echo _SERVER("HTTP_HOST")?>";
      ws = new WebSocket("ws://" + ws_host_addr + "/game", "text.phpoc");
      document.getElementById("ws_state").innerHTML = "CONNECTING";
      ws.onopen = ws_onopen;
      ws.onclose = ws_onclose;
      ws.onmessage = ws_onmessage;
   }
   else
      ws.close();
}


function ws_onopen()
{
   document.getElementById("ws_state").innerHTML = "<font color='blue'>CONNECTED</font>";
   document.getElementById("bt_connect").innerHTML = "DISCONNECT";
   ws.send("init\r\n");
   updated_timer = setInterval(game_process, updated_speed);  
}


function ws_onclose()
{
   document.getElementById("ws_state").innerHTML = "<font color='gray'>NOT CONNECTED</font>";
   document.getElementById("bt_connect").innerHTML = "CONNECT";
   ws.onopen = null;
   ws.onclose = null;
   ws.onmessage = null;
   ws = null;
   clearInterval(updated_timer);
}


function ws_onmessage(e_msg)
{
   if (is_not_finished == true)
   {
      e_msg = e_msg || window.event;    
      user_car.x = parseInt(e_msg.data)*car_width;
   }
}

function get_speed()
{
   return (speed_default - speed_delta*cur_level)
}


function draw_score()
{
   ctx.font = 1.5*block_size+"px Georgia";
   ctx.fillText("SCORES",18*block_size,10*block_size);
   ctx.font = 1.25*block_size+"px Georgia";
   ctx.fillText(""+ cur_score,20*block_size,12*block_size);      

}


function draw_car(obj, is_broken)
{

   ctx.save();
   ctx.translate(obj.x*block_size,obj.y*block_size);
   if (is_broken == false)
   {
      ctx.fillStyle = "#020202";
   }
   else
   {
      ctx.fillStyle = "#202020";
   }
    ctx.fillRect(0, block_size, 3*block_size, block_size);
   ctx.fillRect(block_size, 0, block_size, 3*block_size);
    ctx.fillRect(0, 3*block_size, block_size, block_size);
    ctx.fillRect(2*block_size, 3*block_size, block_size, block_size);

   draw_rectangle(1,0);
   draw_rectangle(1,1);
   draw_rectangle(1,2);
   draw_rectangle(0,1);
   draw_rectangle(2,1);
   draw_rectangle(0,3);
   draw_rectangle(2,3);
    ctx.restore();
}


function draw_rectangle(x,y)
{

   ctx.beginPath();
   ctx.lineWidth= rect_line_width;
   ctx.strokeStyle="#FFFFFF";
   ctx.rect(x*block_size+line_distance,y*block_size+l  ine_distance,block_size-2*line_distance,block_size - 2*line_distance);
   ctx.stroke();
}



function draw_grid()
{

   ctx.save();
   ctx.translate(-2*block_size,0);
   ctx.lineWidth = line_width;      
   ctx.strokeStyle = "#FCFCFC";

   for( var x_id = 0; x_id <= 19; x_id++)
   {
      ctx.beginPath();
      ctx.moveTo(x_id*block_size,0);
      ctx.lineTo(x_id*block_size,block_size*24);
      ctx.stroke();
   }

   for( var y_id = 0; y_id <= 24; y_id++)
   {
      ctx.beginPath();
      ctx.moveTo(0, y_id*block_size);
      ctx.lineTo(block_size*19, y_id*block_size);
      ctx.stroke();
   }  
   ctx.restore();
}


function draw_sideline()
{
   var move_down = 1;
   if (is_not_finished == false)
   {
      move_down = 0;
   }
   for( var y_id = 0; y_id < 14; y_id++)
   {
      ctx.fillStyle = "#020202";
      ctx.fillRect(sidelines[y_id].x*block_size , sidelines[y_id].y*block_size , block_size, 2*block_size);
      draw_rectangle(sidelines[y_id].x,sidelines[y_id].y);
      draw_rectangle(sidelines[y_id].x,sidelines[y_id].y+1);
      sidelines[y_id].y += move_down;
      if (sidelines[y_id].y > (user_car.y + car_height))
      {
         sidelines[y_id].y -= 7*car_height;
      }
   }

}


function move_opponent_cars()
{  
   for (var car_id = 0; car_id < 6; car_id++)
   {
      cur_y = opponent_cars[car_id].y;
      if (cur_y <= (user_car.y + 3))
      {
         opponent_cars[car_id].y += 1;
      }
      else
      {
         cur_score += 1;        
         opponent_cars[car_id].x = (Math.floor(Math.random() * 5))*car_width;
         opponent_cars[car_id].y += (-8*car_height+1);
      }

   }

   level_up = Math.floor(cur_score/10);

   if (level_up>cur_level)
   {
         clearInterval(updated_timer);
         cur_level = level_up;
         updated_speed = get_speed();      
         if (updated_speed == 0)
         {
            game_over();
            return;
         }  
         updated_timer = setInterval(game_process, updated_speed);

   }

   while (shuffle_needed())
   {
      for (var car_id = 0; car_id < 5; car_id++)
      {
         for (var car_id_2nd = car_id+1; car_id_2nd < 6; car_id_2nd++)
         {

            while ((opponent_cars[car_id_2nd].y == opponent_cars[car_id].y)&&
            (Math.abs(opponent_cars[car_id_2nd].x - opponent_cars[car_id].x)<= car_width))
               {

               if (Math.random()>0.5)
               {
                  opponent_cars[car_id_2nd].x = Math.floor(Math.random()* 5)*car_width;
               }
               else
               {                  
                  opponent_cars[car_id_2nd].y -= Math.ceil(Math.random())*car_height;
               }
               }

            while ((opponent_cars[car_id_2nd].x == opponent_cars[car_id].x)&&
            (Math.abs(opponent_cars[car_id_2nd].y - opponent_cars[car_id].y)< 2*car_height))
               {
                  opponent_cars[car_id_2nd].y -= Math.ceil(Math.random())*2;
               }


         }
      }

   }

}



function shuffle_needed()
{
   for (var car_id = 0; car_id < 5; car_id++)
   {
      for (var car_id_2nd = car_id+1; car_id_2nd < 6; car_id_2nd++)
      {

         if ((opponent_cars[car_id_2nd].x == opponent_cars[car_id].x)&&
         (Math.abs(opponent_cars[car_id_2nd].y - opponent_cars[car_id].y)< 2*car_height))
            return true;

         if ((opponent_cars[car_id_2nd].y == opponent_cars[car_id].y)&&
         (Math.abs(opponent_cars[car_id_2nd].x - opponent_cars[car_id].x)<= car_width))  
            return true;            

      }
   }
   return false;

}



function check_crash()
{
   var crash_car_id = null;
   for (var car_id = 0; car_id < 6; car_id++)
   {
      cur_y = opponent_cars[car_id].y;
      if ((cur_y > (user_car.y - car_height)) && (cur_y < (user_car.y + car_height)-1))
      {

         if (((opponent_cars[car_id].x < user_car.x) && (opponent_cars[car_id].x > user_car.last_x)) ||
         ((opponent_cars[car_id].x>user_car.x) && (opponent_cars[car_id].x < user_car.last_x)) || (opponent_cars[car_id].x == user_car.x))
         {

            is_not_finished = false;
            crash_car_id = car_id;  

            if ((Math.abs(opponent_cars[car_id].x - user_car.last_x)) <= (Math.abs(opponent_cars[crash_car_id].x - user_car.last_x)))
            {
               crash_car_id = car_id;  
               user_car.x = opponent_cars[crash_car_id].x;
            }

         }

      }            
   }

   return (!is_not_finished);  
}


function game_over()
{
   ctx.clearRect(-100, 0, cvs_width, cvs_height);

   ctx.font = 2*block_size+ "px Georgia";

   if (is_crashed == true)
   {
      ctx.fillText("GAME OVER", 5*block_size, 10*block_size);  
   }
   else
   {
      ctx.fillText("CONGRATULATION", 2*block_size, 10*block_size);
   }

   ctx.font = 1.5*block_size + "px Georgia";
   ctx.fillText("SCORES", 8*block_size, 12*block_size);
   ctx.font = 1.25*block_size + "px Georgia";
   ctx.fillText(""+ cur_score, 10*block_size, 14*block_size);


}


function blinking()
{

   ctx.clearRect(-100, 0, cvs_width, cvs_height);

   for (var car_id = 0; car_id < 6; car_id++)
   {
      draw_car(opponent_cars[car_id], false);
   }

   draw_score();
   draw_sideline();      
   draw_grid();

   if ((blink_times % 2)==0){        
      draw_car(user_car, true);                  
   }

   if (blink_times > 4)
   {      
      game_over();
   }
   else
   {
      setTimeout(function(){blinking();}, 500);
      blink_times ++;
   }

}


function update_scene()
{
   if (is_not_finished == true)
   {
      ctx.clearRect(-100, 0, cvs_width, cvs_height);


      for (var car_id = 0; car_id < 6; car_id++)
      {
         draw_car(opponent_cars[car_id],false);
      }

      draw_car(user_car,false);      
      draw_score();      
      draw_sideline();      
      draw_grid();

      user_car.last_x = user_car.x;  
   }
}


function game_process()
{
   if(ws != null)
   {      


      is_crashed = check_crash();  


      if (is_crashed==true)
      {        
         clearInterval(updated_timer);
         blinking();

         return;
      }      

      move_opponent_cars();  
      update_scene();


   }
}


window.onload = init;
</script>
</head>

<body>
<center>
<p>
<h1>PHPoC - Car Race </br> Brick Game</h1>
</p>
<canvas id="remote" width="500" height="400" Horizontal-align="middle";></canvas>
<h2>
<p>
WebSocket : <span id="ws_state">null</span>
</p>
<button id="bt_connect" type="button" onclick="connect_onclick();">CONNECT</button>
</h2>
</center>
</body>
</html>