Question

我目前正在为pygame开发一个抽象层，在尝试检查与地图的碰撞时遇到了一个问题。我能够加载和显示地图，以及存储可碰撞的矩形。当我打印矩形列表时，我看到所有内容都已到位，但是当我遍历每个rect并尝试检查与另一个rect的碰撞时，即使rects没有碰撞，它也总是返回true。此外，当我尝试通过在每个部分上绘制一个红色轮廓的矩形来调试所有的部分时，即使我打印矩形时它也会打印出一个存在的矩形。

以下是框架中的一些片段：

class Tilemap(object):
"""This is the tilemap object, it takes an array of strings as its object, and places a surface where you have it in the strings. It only supports one surface per map, so you have to make multiple maps for floor, walls, etc."""
def __init__(self, level_surface,level_string = None, string_char = "#", surface = None, surface_dim = Vector2(50, 50),surface_color = (255, 255, 255)):
    self.level = level_string
    self.char = string_char
    self.surface = surface
    if self.surface is None:
        self.surface = pygame.Surface(surface_dim)
        self.surface.fill(surface_color)

    self.surface_width = self.surface.get_rect().w
    self.surface_height = self.surface.get_rect().h
    self.collision_list = []
    for y in xrange(len(self.level)):
        for x in xrange(len(self.level[y])):
            if self.level[y][x] is self.char:
                self.collision_list.insert(len(self.collision_list), Rect((x) * self.surface_width,(y) * self.surface_height, self.surface_width, self.surface_height))
    print self.collision_list
    for y in xrange(len(self.level)):
        for x in xrange(len(self.level[y])):
            if self.level[y][x] is self.char:
                level_surface.blit(self.surface.convert_alpha(), (self.surface_width * x, self.surface_height * y))

def replace_char_with(self, level_surface,char = ".", surface = None):
    for y in xrange(len(self.level)):
        for x in xrange(len(self.level[y])):
            if self.level[y][x] is char:
                level_surface.blit(surface.convert_alpha(), (surface.get_width() * x, surface.get_height() * y))

def check_col(self, rect):
    for tilerect in self.collision_list:
        if rect.x + rect.w > tilerect.x or rect.y + rect.h > tilerect.y or rect.x < tilerect.x + tilerect.w or rect.y < tilerect.y + tilerect.h:
            return True
        else:
            return False

def debug_draw(self, screen):
    for rect in self.collision_list:
        pygame.draw.rect(screen, (255, 0, 0), rect, 2)

Snippet＃2，测试代码：

def main():
from pygame.locals import K_w, K_a, K_s, K_d
pygame.init()
screen = pygame.display.set_mode((640, 480))
clock = pygame.time.Clock()
player = Sprite(pygame.image.load("trapdoor_tile.png"), Vector2(100, 100))
floor = ["########################################",
         "########################################",
         "#####...##.#.#..###.#.###..#############",
         "#####.######.#.#.####.##.#.#############",
         "######.###.#.##..##.#.###.##############",
         "#####.####.########.####################",
         "#####.#.##.###.#.##.#.##.#.#############",
         "########################################",
         "#######################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################"
         "########################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################",
         "########################################"]

walls = ["########################################",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "#......................................#",
         "########################################"]

level_surf = pygame.Surface((640, 480))
floor_map = Tilemap(level_surf, floor, "#", pygame.image.load("ground_tile.png").convert_alpha())
floor_map.replace_char_with(level_surf, ".", pygame.image.load("trapdoor_tile.png").convert_alpha())
wall_map = Tilemap(level_surf, walls, "#", pygame.image.load("wall_tile.png").convert_alpha())

while True:
    screen.fill((0, 0, 0))
    milliseconds = clock.tick(60) / 10.

    for event in pygame.event.get():
        if event.type == pygame.locals.QUIT:
            pygame.quit()
            raise SystemExit

    wall_map.debug_draw(screen);

    screen.blit(level_surf, Vector2(0, 0))

    if wall_map.check_col(player.dummyrect):
        player.colliding = True
        print "why!"
    else:
        player.colliding = False

    player.update(milliseconds)
    player.draw(screen)

    keystate = pygame.key.get_pressed()

    player.apply_drag()

    if keystate[K_w]:
        player.set_accel_y(-5)
    elif keystate[K_s]:
        player.set_accel_y(5)
    elif keystate[K_a]:
        player.set_accel_x(-5)
    elif keystate[K_d]:
        player.set_accel_x(5)

    pygame.display.flip()

创建播放器的精灵类：

class Sprite(object):
def __init__(self, surface = None, initial_position = (100, 100)):
    self.surface = surface
    self.rect = self.surface.get_rect(center = initial_position)
    self.acceleration = Vector2(0, 0)
    self.delta_time = None
    self.dummyrect = self.rect
    self.colliding = False

def update(self, delta_time):
    self.dummyrect = self.rect.move(self.acceleration.x * delta_time, self.acceleration.y * delta_time)
    if not self.colliding:
        self.rect = self.dummyrect
    else:
        self.dummyrect = self.rect
    self.delta_time = delta_time

def draw(self, screen):
    screen.blit(self.surface, self.rect)

def draw_to_cam(self, screen,camera):
    screen.blit(self.surface, camera.to_camera_coords(Vector2(self.rect.x, self.rect.y)))

def collide(self, rectangle):
    if self.rect.x + self.rect.w > rectangle.x:
        self.rect.x -= 1;
    if self.rect.x < rectangle.x + rectangle.w:
        self.rect.x += 1
    if self.rect.y < rectangle.y + rectangle.h:
        self.rect.y += 1;
    if self.rect.y + self.rect.h > rectangle.y:
        self.rect.y -= 1;

def set_accel_x(self, new_val):
    self.acceleration.x = new_val

def set_accel_y(self, new_val):
    self.acceleration.y = new_val

def apply_drag(self, drag_mul = 1):
    if self.acceleration.x > 0:
        self.acceleration.x -= self.delta_time * drag_mul
    else:
        self.acceleration.x += self.delta_time * drag_mul

    if self.acceleration.y > 0:
        self.acceleration.y -= self.delta_time * drag_mul
    else:
        self.acceleration.y += self.delta_time * drag_mul

    if self.acceleration.x < 0.1 or self.acceleration.x > -0.1:
        self.acceleration.x = 0
    if self.acceleration.x < 0.1 or self.acceleration.x > -0.1:
        self.acceleration.x = 0
    if self.acceleration.y < 0.1 or self.acceleration.y > -0.1:
        self.acceleration.y = 0
    if self.acceleration.y < 0.1 or self.acceleration.y > -0.1:
        self.acceleration.y = 0

def get_center(self):
    return Vector2(self.rect.centerx, self.rect.centery)

这是涉及的三个主要片段，我不知道为什么每次都会返回碰撞，但它似乎是这样做的。如果有人有答案，或至少解释，为什么会发生这种情况，请帮助兄弟！

Answer 1

在碰撞检查中需要一些and。

例如：

def check_col(self, rect):
    for tilerect in self.collision_list:
        collide_x = False
        collide_y = False
        # check x axis for collision
        if self.rect.x + self.rect.w > tilerect.x:
            collide_x = True
        elif self.rect.x < tilerect.x + tilerect.w:
            collide_x = True
        # check y axis for collision
        if self.rect.y < tilerect.y + tilerect.h:
            collide_y = True
        elif self.rect.y + self.rect.h > tilerect.y:
            collide_y = True
        # act on a collision on both axis
        if collide_x and collide_y:
            return True
        else:
            return False

Answer 2

你的check_col函数正在使用所有'或'运算符，这意味着只要满足一个条件，你就会为碰撞返回true。这是你的代码：

def check_col(self, rect):
for tilerect in self.collision_list:
    if rect.x + rect.w > tilerect.x or rect.y + rect.h > tilerect.y or rect.x < tilerect.x + tilerect.w or rect.y < tilerect.y + tilerect.h:
        return True
    else:
        return False

你想要的是更像这样的东西：

def check_col(self, rect):
    for tilerect in self.collision_list:
        if ((rect.x + rect.w > tilerect.x and rect.x <= tilerect.x + tilerect.width) or
            (tilerect.x + tilerect.width > rect.x and tilerect.x <= rect.x + rect.width)) and
            ((rect.y + rect.h > tilerect.y and rect.y <= tilerect.y + tilerect.height) or
            (tilerect.y + tilerect.height > rect.y and tilerect.y <= rect.y + rect.height))

            return true
        else:
            return false

此外，值得指出的是pygame的Rect类有自己的一组碰撞检测功能。要检测2个rects之间的冲突，可以使用rect.colliderect（Rect）。

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

Pygame：碰撞瓷砖不起作用

2 个答案: