获取碰撞的侧面：碰撞检测

Question

我正在尝试做一个平台游戏，其中没有斜坡。我正在尝试将碰撞检测降下来，但是我在pygame中找不到一种方法来获得哪一边与另一个Sprite发生了碰撞。有没有人能给我一个好的方法来做到这一点，那不是太庞大，但也能很好地工作在我的情况？

下面是我的玩家类：

class Player(pg.sprite.Sprite):
    def __init__(self,game):
        pg.sprite.Sprite.__init__(self)
        self.image = pg.Surface((30, 40))
        self.game = game
        self.image.fill(YELLOW)
        self.rect = self.image.get_rect()
        self.rect.center = (WIDTH / 2, HEIGHT / 2)
        self.pos = vec(WIDTH / 2, HEIGHT / 2)
        self.vel = vec(0, 0)
        self.acc = vec(0, 0)

    def jump(self):
        self.rect.y += 1
        hits = pg.sprite.spritecollide(self, self.game.platforms, False)
        self.rect.y -= 1
        if hits:
            self.vel.y = -15

    def update(self):
        self.acc = vec(0, PLAYER_GRAV)
        keys = pg.key.get_pressed()
        if keys[pg.K_LEFT]:
            self.acc.x = -PLAYER_ACC
        if keys[pg.K_RIGHT]:
            self.acc.x = PLAYER_ACC
        self.acc.x += self.vel.x * PLAYER_FRICTION
        self.vel += self.acc
        self.pos += self.vel + 0.5 * self.acc


        self.rect.midbottom = self.pos

class Platform(pg.sprite.Sprite):
    def __init__(self, x, y ,w, h):
        pg.sprite.Sprite.__init__(self)
        self.image = pg.Surface((w,h))
        self.image.fill(GREEN)
        self.rect = self.image.get_rect()
        self.rect.x = x
        self.rect.y = y
        self.centerx = x+(w/2)
        self.centery = y+(h/2)

hits = pg.sprite.spritecollide(self.player,self.platforms, False)

if hits:
    self.player.pos.y = hits[0].rect.top+1
    self.player.vel.y = 0

我已经将它添加到我的player类中，每次播放器更新时我都运行它，并且它工作...差一点。

def wall_collisions(self):
    self.rect.centerx = self.pos.x
    for wall in pg.sprite.spritecollide(self, self.walls, False):
        if self.vel.x > 0:
            self.rect.right = wall.rect.left
            self.vel.x = 0
        elif self.vel.x < 0:
            self.rect.left = wall.rect.right
            self.vel.x = 0
        self.pos.x = self.rect.centerx

    self.rect.centery = self.pos.y
    for wall in pg.sprite.spritecollide(self, self.walls, False):
        if self.vel.y > 0:
            self.rect.bottom = wall.rect.top
            self.vel.y = 0
        elif self.vel.y < 0:
            self.rect.top = wall.rect.bottom
            self.vel.y = 0
        self.pos.y = self.rect.centery

在平台顶部的碰撞起作用，在侧面的碰撞几乎总是起作用，除非我把玩家压在他们身上然后跳。如果我试图打在平台底部的球员，它会把我射到平台的任何一边。有人帮忙吗？

Answer 1

我找到了一个有效的解决办法。下面的代码工作得非常好。

def wall_collisions(self):
    self.rect.centerx = self.pos.x
    for wall in pg.sprite.spritecollide(self, self.walls, False):
        if self.vel.x > 0:
            self.rect.right = wall.rect.left
            self.vel.x = 0
        elif self.vel.x < 0:
            self.rect.left = wall.rect.right
            self.vel.x = 0
        self.pos.x = self.rect.centerx

    self.rect.centery = self.pos.y
    for wall in pg.sprite.spritecollide(self, self.walls, False):
        if self.vel.y > 0:
            self.rect.bottom = wall.rect.top
            self.vel.y = 0
        elif self.vel.y < 0:
            self.rect.top = wall.rect.bottom
            self.vel.y = 0
        self.pos.y = self.rect.centery