Monthly Archives: December 2020

Blob Game with Collision Detection

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<!DOCTYPE html>
<html>
<head>
<style>
body {background-color: Plum;}
canvas{ border: 2px solid black;}
</style>
</head>
<body>
  <img id="link1"  src="link1 (2).png" alt="Link1" style="display:none">
  <img id="link2"  src="link2 (2).png" alt="Link2" style="display:none">
  <img id="grass1"  src="grass1.png" alt="Link2" style="display:none">
  <img id="grass2"  src="grass2.png" alt="Link2" style="display:none">
  <img id="grass3"  src="grass3.png" alt="Link2" style="display:none">
  <img id="grass4"  src="grass4.png" alt="Link2" style="display:none">
  <img id="rock1"  src="rock1.png" alt="Link2" style="display:none">
  <canvas id = "game"></canvas>
<script>
  var Key = {  
    _pressed: {},
    LEFT: 37,
    UP: 38,
    RIGHT: 39,
    DOWN: 40,

    isDown: function(keyCode){
      return this._pressed[keyCode];
    },
 
    onKeydown: function(event) {
      this._pressed[event.keyCode] = true;
    },
 
    onKeyup: function(event) {
      delete this._pressed[event.keyCode];
    }
  };
 
  window.addEventListener('keyup', function(event) {Key.onKeyup(event); }, false);
  window.addEventListener('keydown', function(event) {Key.onKeydown(event); }, false);
  
  var OBSTACLES = [
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,1,1,0,0,0,0,0,0,0,0,0,0],
    [0,1,0,1,0,0,1,0,0,0,0,0,0,0],
    [0,1,1,1,0,1,0,1,0,0,0,0,0,0],
    [0,1,0,1,0,1,1,1,0,0,0,0,0,0],
    [0,1,1,1,0,1,0,1,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,1]
    ];
  
  var canvas = document.getElementById('game');
  canvas.width = 1400; //window.innerWidth;
  canvas.height =900; //window.innerHeight;
  var grid = 100;
  var player_width = document.getElementById("link1").width;
  var player_height = document.getElementById("link1").height;
  //var player_width = document.getElementById("rock1").width;
  //var player_height = document.getElementById("rock1").height;
  console.log(player_width, player_height);
  
  function isCollidedOb(x,y,width,height,obarray){
    upperleft = [[Math.floor(y/grid)],[Math.floor(x/grid)]];
    lowerleft =  [[Math.floor((y+height)/grid)],[Math.floor((x)/grid)]];
    upperright = [[Math.floor((y)/grid)],[Math.floor((x+width)/grid)]];
    lowerright = [[Math.floor((y+height)/grid)],[Math.floor((x+width)/grid)]];
    console.log(upperleft[0],lowerleft,upperright[0],lowerright);
    if(obarray[upperleft[0]][upperleft[1]] || obarray[lowerleft[0]][lowerleft[1]] || obarray[upperright[0]][upperright[1]] || obarray[lowerright[0]][lowerright[1]]){
      return true;
    }
    return false;
  }
  
   function drawObs(obarray,grid){
      for (let i = 0; i < obarray.length; i++) {
          for (let j = 0; j <  obarray[i].length; j++) {
              if (obarray[i][j]){
                ctx.drawImage(rock1,j*grid,i*grid);
              }
          }
      }
   }
  
  var x = 50;
  var y = 50;
  var toggle = 1;
 
  var grass1 = document.getElementById("grass1");
  var rock1 = document.getElementById("rock1");
  var ctx = canvas.getContext('2d');
 
  var goalX = Math.random() * window.innerWidth;
  var goalY = Math.random() * window.innerHeight;
  var playerSize = 50;
  var goalSize = 15;

  var speed = 3;
  function draw() {
   
    ctx.clearRect(0, 0, canvas.width, canvas.height);
    ctx.fillStyle = "rgb(24, 255, 0)";
    ctx.fillRect(0, 0, canvas.width, canvas.height);
    drawObs(OBSTACLES,grid);
    ctx.drawImage(grass1, 200, 200);
    
    //MOVE UP
    if(Key.isDown(Key.UP)){
      toggle += 1;
      if(y < 0){
        y= canvas.height-player_height;
      }
      if(!isCollidedOb(x,Math.abs(y-speed),player_width,player_height,OBSTACLES)){
        y-=speed;
      }
    }
    
    //MOVE DOWN
    if(Key.isDown(Key.DOWN)){
      toggle += 1;
      if(y > canvas.height){
        y= y%canvas.height;
      }
      if(!isCollidedOb(x,y+speed,player_width,player_height,OBSTACLES)){
        y+=speed;
      } 
    }
    
    //MOVE LEFT
    if(Key.isDown(Key.LEFT)){
      toggle += 1;
      if(x < 0){
        x = canvas.width-player_width;
      }
      if(!isCollidedOb(x-speed,y,player_width,player_height,OBSTACLES)){
        x-=speed;
      }
    }
    
    //MOVE RIGHT
    if(Key.isDown(Key.RIGHT)){
      toggle += 1;
      if(x > canvas.width){
        x= x%canvas.width;
      }
      if(!isCollidedOb(x+speed,y,player_width,player_height,OBSTACLES)){
        x+=speed;
      }
    }
   
    if ((Math.abs(x-goalX))**2 + (Math.abs(y-goalY))**2 < (playerSize+goalSize)**2){
      //playerSize += 5;
      goalX = Math.random() * canvas.width;
      goalY = Math.random() * canvas.height;
    }
    //var character = new Path2D();
    ////////////////////////////////////////////////////////////////////
     //var character = new Image();
    //toggle += 1;
    toggle %= 100;
    if(toggle > 50){
    var character = document.getElementById("link1");
      //character.src = document.getElementById("link1");
    } else {
    //character.src = document.getElementById("link2");}
    var character = document.getElementById("link2");}
    //character.addEventListener('load', function() {
     // execute drawImage statements here
    ctx.drawImage(character, x, y);
    
    var goal = new Path2D();
    goal.arc(goalX, goalY, goalSize, 0, 2 * Math.PI);
   
    ctx.fillStyle = "#FF0000"
    //ctx.fill(character);
   
    ctx.fill(goal)
  }
  setInterval(draw, 10);
 
</script>
</body>
</html>