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pythonpygamedraw

How to delete a single pygame drawing from the screen?


When the big circle touches the little circles I want the little circle that it touched to disappear from the screen. However, I can't figure out how exactly you delete an individual drawing in pygame. How do I fix this issue? does pygame have this feature built-in?

from pygame import *
import random as rd
import math as m

init()
screen = display.set_mode((800, 600))

p_1_x = 200
p_1_y = 200
p_1_change_x = 0
p_1_change_y = 0

def p_1(x, y):
    player_1 = draw.circle(screen, (0, 0, 0), (x, y), 15)

def pick_up(x, y, xx, yy):
    distance = m.sqrt(m.pow(xx - x, 2) + m.pow(yy - y, 2))
    if distance < 19:
        # I think the code to delete should go here
        pass

dots = []
locations = []

for i in range(5):
    x = rd.randint(100, 700)
    y = rd.randint(100, 500)
    locations.append((x, y))

while True:
    screen.fill((255, 255, 255))
    for events in event.get():
        if events.type == QUIT:
            quit()
        if events.type == KEYDOWN:
            if events.key == K_RIGHT:
                p_1_change_x = 1
            if events.key == K_LEFT:
                p_1_change_x = -1
            if events.key == K_UP:
                p_1_change_y += 1
            if events.key == K_DOWN:
                p_1_change_y -= 1

        if events.type == KEYUP:
            if events.key == K_RIGHT or K_LEFT or K_UP or K_DOWN:
                p_1_change_x = 0
                p_1_change_y = 0

    p_1_x += p_1_change_x
    p_1_y -= p_1_change_y
    for i, locate in enumerate(locations):
        dot = draw.circle(screen, (0, 0, 0), locate, 5)
        dots.append(dot)
        for l in enumerate(locate):
            pick_up(p_1_x, p_1_y, locate[0], locate[1])

    p_1(p_1_x, p_1_y)
    display.update()

Solution

  • Your code was so messy and hard to maintain, first I made 2 classes for Balls & Dots. I detect collision by pygame.Rect.colliderect, first I make 2 rectangle then I check the collision like this:

    def pick_up(ball, dot):
        ball_rect = Rect( ball.x - ball.SIZE , ball.y - ball.SIZE , ball.SIZE*2, ball.SIZE*2)
        dot_rect = Rect( dot.x - dot.SIZE , dot.y - dot.SIZE , dot.SIZE*2, dot.SIZE*2)
        if ball_rect.colliderect(dot_rect): 
            return True
        return False
    

    If collision detects I remove it from dots array in the while loop:

    for dot in dots:
        if pick_up(ball, dot): # if dot in range ball
                dots.remove(dot)
        dot.draw()
    

    Here is the whole source:

    from pygame import *
    import random as rd
    
    SCREEN_WIDTH = 800
    SCREEN_HEIGHT = 600
    NUMBER_OF_DOTS = 5
    
    class Ball():
        SIZE = 15
        def __init__(self, x, y):
            self.x = x
            self.y = y
            
        def draw(self):
            draw.circle(screen, (0, 0, 0), (self.x, self.y), Ball.SIZE)
        def move(self, vx, vy):
            self.x += vx
            self.y += vy
    
    class Dot():
        SIZE = 5    
        def __init__(self, x, y):
            self.x = x
            self.y = y
            
        def draw(self):
            draw.circle(screen, (0, 0, 0), (self.x, self.y), Dot.SIZE)
    
    
    def pick_up(ball, dot):
        ball_rect = Rect( ball.x - ball.SIZE , ball.y - ball.SIZE , ball.SIZE*2, ball.SIZE*2)
        dot_rect = Rect( dot.x - dot.SIZE , dot.y - dot.SIZE , dot.SIZE*2, dot.SIZE*2)
        if ball_rect.colliderect(dot_rect): 
            return True
        return False
    
    
    
    init()
    screen = display.set_mode((SCREEN_WIDTH, SCREEN_HEIGHT))
    
    dots = []
    ball = Ball(200,200)
    
    # generate dots
    for i in range(NUMBER_OF_DOTS):
        x = rd.randint(100, 700)
        y = rd.randint(100, 500)
        dots.append(Dot(x,y))
    
    # the main game loop
    while True:
        screen.fill((255, 255, 255))
        keys=key.get_pressed()
    
        for events in event.get():
            keys=key.get_pressed()
            if events.type == QUIT:
                quit()
    
        if keys[K_RIGHT]:
            ball.move(+1,0)
        if keys[K_LEFT]:
            ball.move(-1,0)
        if keys[K_UP]:
            ball.move(0,-1)
        if keys[K_DOWN]:
            ball.move(0,+1)
    
        for dot in dots:
            dot.draw()
            
            if pick_up(ball, dot):
                    dots.remove(dot)
    
        ball.draw()
        display.update()
        time.delay(1) # Speed down
    

    Update1:

    PyGame Rectangle Collision http://www.pygame.org/docs/ref/rect.html#pygame.Rect.colliderect

    Update2:

    I make a repo in the github and did some changes,
    Dots are colorful, new dot gets random color and the ball gets bigger whenever eats a dot. shot

    https://github.com/peymanmajidi/Ball-And-Dots-Game__Pygame