JSFiddle - React, Tailwind, and code Playground

HTML

<canvas style="z-index: 0;" id="canvas" width="480" height="380"></canvas>  
<div id="debug1"></div>
<div id="debug2"></div>
<div id="debug3"></div>
<div id="debug4"></div>
<div id="debug5"></div>
<canvas style="z-index: 0;" id="topdowncanvas" width="480" height="480"></canvas>

JavaScript

var canvas = document.getElementById('canvas');
                var ctx = document.getElementById('canvas').getContext('2d');

                var topdown = document.getElementById('topdowncanvas');
                var topdownCtx = document.getElementById('topdowncanvas').getContext('2d');

                var rightKey = false,
                leftKey = false,
                upKey = false,
                downKey = false;

                var timeAtLastFrame = new Date().getTime();
                var idealTimePerFrame = 1000 / 30;
                var leftover = 0.0;
                var frames = 0;

                var playerX = 50;
                var playerY = 50;

                playerX = Math.floor(Math.random() * 8000);
                playerY = Math.floor(Math.random() * 8000);

                var isometricTiles = new Array();
                var topdownTiles = new Array();

                var tileMap = new Array();

                for (x = 0; x < 250; x++) {
                    var row = new Array();
                    for (y = 0; y < 250; y++) {
                        row[y] = Math.floor(Math.random() * 3);
                    }
                    tileMap[x] = row;
                }

              

                init();


                function init() {
                    loadImg();
                    document.addEventListener('keydown', keyDown, false);
                    document.addEventListener('keyup', keyUp, false);
                    setInterval(gameLoop, 1000 / 30);
                    topdown.addEventListener('mousemove', mouseMove);
                }

                function mouseMove (e) {
                    var offset = topdown.offsetTop;
                    var x = e.pageX;
                    var y = e.pageY-offset;
                    //alert ( y ); 240
                    //draw ( x, y );
                    positionToUser ( x, y );
                }

                function positionFromUser ( x, y ) {
    
            ...