F

function Player(){
  this.x = width/2+10;
  this.y = height/2-20;
  this.grounded = true;
  this.show = function(){
    fill(255);
    square(this.x,this.y,20);
  }
  this.testCollisions = function(other){
    if (this.x < other.x+other.w && other.x < this.x+this.w &&
        this.y < other.y+other.h && other.y < this.y+this.h) {
      print("collision")
          this.grounded = true;
    } else {
          this.grounded = false;
    }
  }
  this.affectGravity = function(){
    if (!this.grounded)
      this.y+=1;
  }
}

function Block(x,y,grassed){
  this.grassed = grassed; // bool
  this.x = x; // float
  this.y = y;
  this.h = 40;
  this.w = 40;
  this.gh = 15;
  this.gw = 40;
  this.render = function(){
    if (this.grassed){
      fill("#AF7250");
      rect(this.x,this.y,this.w,this.h);
      fill("#869336");
      rect(this.x,this.y,this.gw,this.gh);
    }
  }
}

var block;
var player;
var grounded = true;
function setup() {
  createCanvas(400, 400);
  block = new Block(height/2,width/2,true);
  player = new Player();
}

function draw() {
  background(120);
  block.render();
  player.show();
  if (keyIsDown(LEFT_ARROW)){
    player.x --;
  } else if (keyIsDown(RIGHT_ARROW)){
    player.x ++;
  }
  strokeWeight(1);
  player.testCollisions(block);
  player.affectGravity();
  console.log(player.grounded);
}
function keyPressed(){
  if (player.grounded && keyCode === 32){
    for (let i = 0; i < 10; i++)
      player.y-=1;
  }
}