I wanted to make a game, where player can move to any arrow and get a point for so.

I can render the text, but cannot update it.

I researched but no answer is there.

My code was:

import pygame, sys
from pygame.locals import *
import random
import time

pygame.init()
 
FPS = 60
FramePerSec = pygame.time.Clock()

BLACK = (0, 0, 0)
WHITE = (255, 255, 255) 
GRAY = (200, 200, 200)

SCREEN_WIDTH = 400
SCREEN_HEIGHT = 600

running = True
display = pygame.display.set_mode((400,600))
display.fill(WHITE)
pygame.display.set_caption("Game")


class Up(pygame.sprite.Sprite):
      def __init__(self):
        super().__init__() 
        self.image = pygame.image.load("up.png")
        self.rect = self.image.get_rect()   
        self.rect.center=(40,0) 
        self._layer = self.rect.bottom 
 
      def move(self):
        self.rect.move_ip(0,10)
        if (self.rect.bottom > 600):
            self.rect.top = 0
            self.rect.center = (random.randint(30, 370), 0)
 
      def draw(self, surface):
        surface.blit(self.image, self.rect) 

class Down(pygame.sprite.Sprite):
      def __init__(self):
        super().__init__() 
        self.image = pygame.image.load("down.png")
        self.rect = self.image.get_rect()   
        self.rect.center=(40,0) 
        self._layer = self.rect.bottom 
 
      def move(self):
        self.rect.move_ip(0,10)
        if (self.rect.bottom > 600):
            self.rect.top = 0
            self.rect.center = (random.randint(30, 370), 0)
 
      def draw(self, surface):
        surface.blit(self.image, self.rect)

class Left(pygame.sprite.Sprite):
      def __init__(self):
        super().__init__() 
        self.image = pygame.image.load("left.png")
        self.rect = self.image.get_rect()   
        self.rect.center=(random.randint(40,SCREEN_WIDTH-40),0) 
        self._layer = self.rect.bottom 
 
      def move(self):
        self.rect.move_ip(0,10)
        if (self.rect.bottom > 600):
            self.rect.top = 0
            self.rect.center = (random.randint(30, 370), 0)
 
      def draw(self, surface):
        surface.blit(self.image, self.rect) 

class Right(pygame.sprite.Sprite):
      def __init__(self):
        super().__init__() 
        self.image = pygame.image.load("right.png")
        self.rect = self.image.get_rect()   
        self.rect.center=(random.randint(40,SCREEN_WIDTH-40),0)
        self._layer = self.rect.bottom 
 
      def move(self):
        self.rect.move_ip(0,10)
        if (self.rect.bottom > 600):
            self.rect.top = 0
            self.rect.center = (random.randint(30, 370), 0)
 
      def draw(self, surface):
        surface.blit(self.image, self.rect) 


E1 = Up()
E2 = Down()
E3 = Left()
E4 = Right()

global rt, score
rt, score = 2, 0,
text = f"Score: {score}"

def change(val):
    global rt
    rt = val

def getpoint():
    global score, text
    score += 1
    text = f"Score: {score}"

font = pygame.font.SysFont("Arial.ttf", 18)
img = font.render(f'Score: {score}', True, BLACK)
display.blit(img, (20, 20))

class Player(pygame.sprite.Sprite):
    def __init__(self): 
        super().__init__() 
        self.image = pygame.image.load("Player.png")
        self.rect = self.image.get_rect()
        self.rect.center = (160, 520)
    def update(self):
        pressed_keys = pygame.key.get_pressed()
        if self.rect.left > 0:
            if pressed_keys[K_LEFT]:
                self.rect.move_ip(-10, 0)
        if self.rect.right < SCREEN_WIDTH:        
            if pressed_keys[K_RIGHT]:
                self.rect.move_ip(10, 0)
        
        collide = {
            "1": "self.rect.colliderect(E1.rect)",
            "2": "self.rect.colliderect(E2.rect)",
            "3": "self.rect.colliderect(E3.rect)",
            "4": "self.rect.colliderect(E4.rect)"
        }

        if eval(collide[str(rt)]):
            change(random.randint(1, 4))
            getpoint()
 
    def draw(self, surface):
        surface.blit(self.image, self.rect)     
 
         
P1 = Player()

font = pygame.font.SysFont(None, 48)
img = font.render(text, True, BLACK)
rect = img.get_rect()
rect.topleft = (20, 20)

while running:   
    for event in pygame.event.get():              
        if event.type == QUIT:
            running = False
    
    P1.update()
    eval(f"E{rt}.move()")

    display.fill(WHITE)
    display.blit(img, rect)
    P1.draw(display)
    eval(f"E{rt}.draw(display)") 
    pygame.display.update()
    FramePerSec.tick(FPS)

pygame.quit()

---

My game assets:

down.png:

up.png:

left.png:

right.png:

Player.png:

---

Output: Score displayed does not change

I need to get the score in screen changing, the variable "score" changes.

>Solution :

It is not enough to change the variable score. The rendered txt does not magically change when you change the score. The image surface is not somehow tied toe the vaiable score. You have to render the text again.

def getpoint():
    global score, text, img 
    score += 1
    text = f"Score: {score}"
    img = font.render(text , True, BLACK)