meyer0095 meyer0095 - 3 months ago 11
Python Question

Pygame: Collision by Sides of Sprite

Is there a way in pygame to look for a collision between the a particular side of a sprite and a particular side of another sprite in pygame? For example, if the top of sprite A collides with the bottom of Sprite B, return True.

I am certain there is a way to do this, but I can't find any particular method in the documentation.

Thanks!

Answer

There is no function to get sides collision in PyGame.

But you could try to use pygame.Rect.collidepoint to test if A.rect.midleft, A.rect.midright, A.rect.midtop, A.rect.midbottom, A.rect.topleft, A.rect.bottomleft , A.rect.topright, A.rect.bottomright are inside B.rect (pygame.Rect).


EDIT:

Example code. Use arrows to move player and touch enemy.

(probably it is not optimal solution)

import pygame

WHITE = (255,255,255)
BLACK = (0  ,0  ,0  )
RED   = (255,0  ,0  )
GREEN = (0  ,255,0  )
BLUE  = (0  ,0  ,255)

class Player():

    def __init__(self, x=0, y=0, width=150, height=150):

        self.rect = pygame.Rect(x, y, width, height)

        self.speed_x = 5
        self.speed_y = 5

        self.move_x = 0
        self.move_y = 0

        self.collision = [False] * 9

        self.font = pygame.font.SysFont("", 32)
        self.text = "";

    def set_center(self, screen):
        self.rect.center = screen.get_rect().center

    def event_handler(self, event):
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_LEFT:
                self.move_x -= self.speed_x
            elif event.key == pygame.K_RIGHT:
                self.move_x += self.speed_x
            elif event.key == pygame.K_UP:
                self.move_y -= self.speed_y
            elif event.key == pygame.K_DOWN:
                self.move_y += self.speed_y

        elif event.type == pygame.KEYUP:
            if event.key == pygame.K_LEFT:
                self.move_x += self.speed_x
            elif event.key == pygame.K_RIGHT:
                self.move_x -= self.speed_x
            elif event.key == pygame.K_UP:
                self.move_y += self.speed_y
            elif event.key == pygame.K_DOWN:
                self.move_y -= self.speed_y

    def update(self):
        self.rect.x += self.move_x
        self.rect.y += self.move_y

    def draw(self, screen):

        pygame.draw.rect(screen, WHITE, self.rect, 2)
        self.draw_point(screen, self.rect.topleft, self.collision[0])
        self.draw_point(screen, self.rect.topright, self.collision[1])
        self.draw_point(screen, self.rect.bottomleft, self.collision[2])
        self.draw_point(screen, self.rect.bottomright, self.collision[3])

        self.draw_point(screen, self.rect.midleft, self.collision[4])
        self.draw_point(screen, self.rect.midright, self.collision[5])
        self.draw_point(screen, self.rect.midtop, self.collision[6])
        self.draw_point(screen, self.rect.midbottom, self.collision[7])

        self.draw_point(screen, self.rect.center, self.collision[8])

    def draw_point(self, screen, pos, collision):
        if not collision:
            pygame.draw.circle(screen, GREEN, pos, 5)
        else:
            pygame.draw.circle(screen, RED, pos, 5)

    def check_collision(self, rect):
        self.collision[0] = rect.collidepoint(self.rect.topleft)
        self.collision[1] = rect.collidepoint(self.rect.topright)
        self.collision[2] = rect.collidepoint(self.rect.bottomleft)
        self.collision[3] = rect.collidepoint(self.rect.bottomright)

        self.collision[4] = rect.collidepoint(self.rect.midleft)
        self.collision[5] = rect.collidepoint(self.rect.midright)
        self.collision[6] = rect.collidepoint(self.rect.midtop)
        self.collision[7] = rect.collidepoint(self.rect.midbottom)

        self.collision[8] = rect.collidepoint(self.rect.center)

    def render_collision_info(self):

        text = "collision: "
        print "collision:",

        if self.collision[0] or self.collision[2] or self.collision[4]:
            text += "left "
            print "left",

        if self.collision[1] or self.collision[3] or self.collision[5]:
            text += "right "
            print "right",

        if self.collision[0] or self.collision[1] or self.collision[6]:
            text += "top "
            print "top",

        if self.collision[2] or self.collision[3] or self.collision[7]:
            text += "bottom "
            print "bottom",

        if self.collision[8]:
            text += "center "
            print "center",

        print

        self.text = self.font.render(text, 1, WHITE)

    def draw_collision_info(self, screen, pos):
        screen.blit(self.text, pos)

#----------------------------------------------------------------------

class Game():

    def __init__(self):

        pygame.init()

        self.screen = pygame.display.set_mode( (800,600) )
        pygame.display.set_caption("Side Collision")

        self.player = Player()
        self.enemy  = Player()
        self.enemy.set_center(self.screen)


    def run(self):
        clock = pygame.time.Clock()

        RUNNING = True

        while RUNNING:

            # --- events ----

            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    RUNNING = False

                elif event.type == pygame.KEYDOWN:
                    if event.key == pygame.K_ESCAPE:
                        RUNNING = False

                self.player.event_handler(event)

            # --- updates ---

            self.player.update()
            self.enemy.update()

            self.player.check_collision(self.enemy.rect)
            self.enemy.check_collision(self.player.rect)
            self.player.render_collision_info()
            self.enemy.render_collision_info()

            # --- draws ----

            self.screen.fill(BLACK)

            self.player.draw(self.screen)
            self.enemy.draw(self.screen)

            self.player.draw_collision_info(self.screen, (0,0))
            self.enemy.draw_collision_info(self.screen, (0,32))

            pygame.display.update()

            # --- FPS ---

            clock.tick(30)

        pygame.quit()

#----------------------------------------------------------------------

Game().run()

enter image description here


EDIT (08.2016): version with colllisions rect, rect_ratio, circle

https://github.com/furas/my-python-codes/tree/master/pygame/collisions

enter image description here