Ok

void setup() {
  size(displayWidth, displayHeight ) ;
  orientation(LANDSCAPE) ;
  noStroke() ;
  textFont(createFont("Arial", 200));
}

int px = 860;
int py = 440;
float ok = -15;
int ok1 = 0;
int ok2 = 0;
int text = 200;
int cx = 1830;
int cx1 = 1830;
int cx2 = 1830;
int cx3 = 1830;
int cx4 = 1830;

boolean jump = false;
boolean start = true;
boolean play = false;
boolean dead = false;

void draw() {
  fill(0, 0, 100);
  rect(0, 0, displayWidth, displayHeight ) ;
  fill(0,0,200);
  rect(random(0,1870),random(0,490),50,50);
  rect(random(0,1870),random(0,490),50,50);
  rect(random(0,1870),random(0,490),50,50);
  fill(10,25,35);
  rect(0, 540, displayWidth, 540);
  fill(7,20,30);
  rect(0,640,displayWidth, 440);
  fill(5,15,20);
  rect(0,740,displayWidth, 340);
  fill(3,10,15);
  rect(0,840,displayWidth, 240);
  fill(1, 5,6);
  rect(0,940,displayWidth, 140);
  fill(0);
  rect(0,1040,displayWidth, 40);
  fill(44,155,173);
  rect(px, py, 100, 100);
  fill(32,191,218);
  rect(px+10,py+10,80,80);
  fill(22,207,230);
  rect(px+20,py+20,60,60);
  fill(0,227,255);
  rect(px+30,py+30,40,40);


  if (start &&! play) {
    cx1 = 1830;
    dead = false;
    px = 860;
    fill(0, 100, 100, text);
    text("START", 610, 340);
    ok1++;
    if (ok1 ==25) {
      if (text ==0) {
        text = 200;
      } else {
        text = 0;
      }
      ok1 = 0;
    }
    if (mouseX >=600 && mouseX <= 1280 && mouseY <=350 && mouseY >=150) {
      start = false;
      play = true;
      cx = 1830;
    }
  }

  if (play) {
    fill(71, 0, 255);
    rect(cx, 490, 50, 50) ;
    cx-=10;
    if (cx <= 1000) {
      fill(133,0,0);
      rect(cx1, 440, 100, 100);


      cx1-=10;
      if (px+100>=cx1 && px+100<=cx1+100 && py<=440) {
        if (! mousePressed) {
          jump = false;
        }
      }
      if(py+100>=441&&px+100>cx1&&px+100<=cx1+100){
        dead = true;
      }
      if (px>=cx1+100 && py<=440 && py<=859 && ! jump) {
        py+=10;
      }
    }
    if ((px >= cx && px <= cx+50 && py+100>=490) || (px +100>= cx && px +100<= cx+50 && py + 100>=490) ) {
      dead = true;
      play = false;
    }

    if(cx1<=1650){
      fill(0) ;
      rect(cx2, 400,100,140);
      fill(71,0,255);
      rect(cx2+20,410,60, 120);
      cx2-=10;
      if(((px+90 >= cx2 && px +100 <= cx2+100)||(px<=cx2+100 && px >= cx2)) && py +100 >= 400){
        dead = true;
        play = false;
      }
    }
  }

  if (dead) {
    start = true;
    play = false;
    cx = 1880;
    py = 440;
    cx1 = 1830;
    cx2 = 1830;
  }

  if (mousePressed) {
    jump = true;
  }

  if (jump) {
    py+=ok;
    ok+=1;
    if (py>=440) {
      ok = -15.0;
      jump = false;
    }
  }
  else{
    ok = - 15;
  }

  if(py>440){
    py = 440;
  }
}