How to select individual sprites for movement by clicking them?

Question

I am struggling to be able to move individual cars in my game. I want it so that when you click on a car and move the arrow keys, the selected car is the only one that moves. I have created a Point class and begun to write some code about that colliding with the cars to select them however I'm unsure what to do next. Can anyone help me to be able to select different cars by clicking on them and then be able to move that car alone.

Here is my code:

import pygame, random, time

pygame.init()

class Point(pygame.sprite.Sprite):
    def __init__(self,x,y):
        super().__init__()
        self.rect=pygame.Rect(x,y,0,0)


class Car(pygame.sprite.Sprite):
    def __init__(self,image,spawnx,spawny):
        super().__init__()

                
        self.image= pygame.Surface((100,100))
        self.image = image


        self.type = "car"

        self.rect = self.image.get_rect()
        self.rect.x = spawnx
        self.rect.y = spawny

      
    

        cars.add(self)

    def move(self, dx, dy):
        self.rect.x += dx
        self.rect.y += dy



screen = pygame.display.set_mode((1150, 650))
background_image = pygame.image.load("carpark2.jpg")



cars=pygame.sprite.Group()


clock = pygame.time.Clock()

done = False


black=Car(pygame.image.load("blackcar.png").convert_alpha(),100,100)
blue=Car(pygame.image.load("bluecar.png").convert_alpha(),200,100)
yellow=Car(pygame.image.load("yellowcar.png").convert_alpha(),300,100)
purple=Car(pygame.image.load("purplecar.png").convert_alpha(),400,100)
orange=Car(pygame.image.load("orangecar.png").convert_alpha(),500,100)
white=Car(pygame.image.load("whitecar.png").convert_alpha(),600,100)
green=Car(pygame.image.load("greencar.png").convert_alpha(),700,100)
brown=Car(pygame.image.load("browncar.png").convert_alpha(),800,100)
pink=Car(pygame.image.load("pinkcar.png").convert_alpha(),900,100)

current_car=Car(pygame.image.load("redcar.png").convert_alpha(),100,400)


while done==False:

    clock.tick(30)
    
        
    for event in pygame.event.get():

        if event.type == pygame.MOUSEBUTTONDOWN:
            x,y = event.pos

            for car in pygame.sprite.spritecollide(Point(x,y,), cars, False):
                current_car.deselect()
                current_car = car.select()

                
        if event.type == pygame.KEYDOWN:

            if event.key == pygame.K_LEFT:
                current_car.move(-50,0)
            if event.key == pygame.K_RIGHT:
                current_car.move(50,0)
                
            if event.key == pygame.K_UP:
                black.move(0,-50)
            if event.key == pygame.K_DOWN:
                black.move(0,50)



    screen.blit(background_image, [0, 0])
    cars.draw(screen)
    


    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            done = True

    pygame.display.flip()

pygame.quit()

Did you change `self.rect=pygame.Rect(x,y,0,0)` to `self.rect=pygame.Rect(x, y, 1, 1)`? — Rabbid76, Aug 18 '21 at 17:05

Rabbid76 · Answer 1 · 2021-08-18T17:05:59.123

The pygame.Rect object needs to have a size of at least 1x1:

~~self.rect=pygame.Rect(x,y,0,0)~~

self.rect=pygame.Rect(x, y, 1, 1)

Anyway, I recommend to use pygame.Rect.collidepoint instead of pygame.sprite.spritecollide.
You don't need a select and deselect method at all. Just set current_car = car:

for car in cars:
    if car.rect.collidepoint(x, y):
        current_car = car

Application loop:

while done==False:
    clock.tick(30)
       
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            done = True

        if event.type == pygame.MOUSEBUTTONDOWN:
            x,y = event.pos
            for car in cars:
                if car.rect.collidepoint(x, y):
                    current_car = car
      
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_LEFT:
                current_car.move(-50,0)
            if event.key == pygame.K_RIGHT:
                current_car.move(50,0)
            if event.key == pygame.K_UP:
                current_car.move(0,-50)
            if event.key == pygame.K_DOWN:
                current_car.move(0,50)

    screen.blit(background_image, [0, 0])
    cars.draw(screen)
    pygame.display.flip()

How to select individual sprites for movement by clicking them?

1 Answers1