Issue with FirstPersonController in Ursina

I’m using the Ursina engine to create a 3D game. However, when I try to load the FirstPersonCharacter, all I got is a grey background (normal) and a very small magenta square, in the center, tilted at 45°. What is that ?

I was first trying to make my own mechanics for a first person character, move the camera according to the mouse position (I have this), and I was playing with math and stuff for movements… I was looking at this video (https://www.youtube.com/watch?v=DHSRaVeQxIk) for totally something else, and I found out about the FirstPersonController.

But, with the (almost) same code as him, it doesn’t work ! What’s that issue, has someone already ran into it ? Is FirstPersonController broken ? Or is my brain broken ?

Edit : found out in the ursina cheatsheet that the small magenta tilted square is the cursor. But I still can’t move, can’t have gravity or anything ? And I can’t see my floor.

Second edit : using some piece of code the ursina cheatsheet provided, arranged, I can now see my floor. But I can only move the camera on 1 axis (up and down), I can’t move, no gravity, nothing…

Here is my code :

from ursina import *
from ursina.prefabs.first_person_controller import FirstPersonController

app = Ursina()

window.title = 'The lab'
window.borderless = False
window.fullscreen = True
window.exit_button.visible = False
window.fps_counter.enabled = True

floorcubes = []
for i in range(-20, 20, 2):
    for j in range(-20, 20, 2):
        floorcubes.append(Entity(model='cube', color=color.white, scale=(2,2,2), position = (i, 0, j)))
player = FirstPersonController()
app.run()

Here is the code provided in the ursina cheatsheet, arranged a bit :

from ursina import *
from ursina.prefabs.first_person_controller import FirstPersonController
app = Ursina()
ground = Entity(model='plane', scale=(100,1,100), color=color.yellow.tint(-.2), texture='white_cube', texture_scale=(100,100), collider='box', position = (0, -2, 0), grounded = True)
e = Entity(model='cube', scale=(1,5,10), x=2, y=.01, rotation_y=45, collider='box', texture='white_cube')
e.texture_scale = (e.scale_z, e.scale_y)
e = Entity(model='cube', scale=(1,5,10), x=-2, y=.01, collider='box', texture='white_cube')
e.texture_scale = (e.scale_z, e.scale_y)

player = FirstPersonController(model='cube', y=2, origin_y=-.5, gravity = 1)
player.gun = None

gun = Button(parent=scene, model='cube', color=color.blue, origin_y=-.5, position=(3,0,3), collider='box')
gun.on_click = Sequence(Func(setattr, gun, 'parent', camera), Func(setattr, player, 'gun', gun))

gun_2 = duplicate(gun, z=7, x=8)
slope = Entity(model='cube', collider='box', position=(0,0,8), scale=6, rotation=(45,0,0), texture='brick', texture_scale=(8,8))
slope = Entity(model='cube', collider='box', position=(5,0,10), scale=6, rotation=(80,0,0), texture='brick', texture_scale=(8,8))

def input(key):
    if key == 'left mouse down' and player.gun:
        gun.blink(color.orange)
        bullet = Entity(parent=gun, model='cube', scale=.1, color=color.black)
        bullet.world_parent = scene
        bullet.animate_position(bullet.position+(bullet.forward*50), curve=curve.linear, duration=1)
        destroy(bullet, delay=1)
app.run()

Thanks to the answer, I have now :

from ursina import *
from ursina.prefabs.first_person_controller import FirstPersonController
import pyautogui
import random
import math

app = Ursina()

is_fullscreen = True
window.title = 'The lab'
window.borderless = False
window.fullscreen = is_fullscreen
window.exit_button.visible = False
window.fps_counter.enabled = True

latest_mouse_pos = pyautogui.position()
pyautogui.FAILSAFE = False
sensibility = 2.5
mouse.visible = True


floorcube = Entity(model="cube", color = color.white, scale=(20, 1, 20), collider="box", position=(0, -100, 0))


def update():
    global latest_mouse_pos
    if held_keys['f']:
        camera.fov += 1
    if held_keys['r']:
        camera.fov -= 1

player = FirstPersonController()

app.run()