Snake与pygame方法-像素重叠问题

Question

我开始玩pygame，到目前为止我做得还不错。我遇到了一个问题，并设法解决了它。解决方案是可能的。它不是100%正确的。我想在受试者的头部与食物相遇时实施一种进食方法。当X和Y的其余值等于被吃掉的蛇头时，这可能是一个相对简单的方法。由于某种原因，我无法完全理解像素的重叠，而且我的方法也不正确。

目前的问题是在像素和"像素"之间没有重叠；吃不完"；。

BACKGROUND = pygame.image.load("background.jpg")
WIDTH, HEIGHT = BACKGROUND.get_width(), BACKGROUND.get_height()
pygame.font.init()
WIN = pygame.display.set_mode((WIDTH, HEIGHT))

def checkForEat(self):
head = self.body[-1]
x = self.food.getPos()[0]
y= self.food.getPos()[1]
# if abs(head[0] - x ) < 9 and abs(head[1] - y ) < 9: -- This is my temporary solution
if head[0] == x  and head[1] == y:
self.food = Food()
self.eat()

我尽量不添加太多不必要的代码。

class Food:
def __init__(self):
self.color = (5, 5, 255)
self.pos = (random.randint(10,WIDTH-50),random.randint(10,HEIGHT-50))
def draw(self,win):
pygame.draw.circle(win,self.color, self.pos, 5)
def getPos(self):
return self.pos

class Snake:
START_POS = (85, 85)
def __init__(self):
self.food = Food()
self.block_size = 11
self.x , self.y = self.START_POS
self.body = self.create_body()
def create_body(self):
body = []
for i in range(self.length):
body.append((85,85+i*self.block_size))
return body

def draw(self,win):
WIN.blit(BACKGROUND, (0, 0))
self.food.draw(win)
for i in range(self.length):
pygame.draw.circle(win, (255, 0, 0), self.body[i], 5)

I'm not adding the rest of the program.
Just saying that apart from the problem I wrote above everything works fine.

Answer 1

使用pygame.Rect/pygame.Rect.colliderect检查食物的边界矩形是否与蛇的头部重叠：

class Food:
def __init__(self):
self.color = (5, 5, 255)
self.pos = (random.randint(10,WIDTH-50),random.randint(10,HEIGHT-50))
def draw(self,win):
pygame.draw.circle(win,self.color, self.pos, 5)
def getPos(self):
return self.pos
def getRect(self):
return pygame.Rect(self.pos[0]-5, self.pos[1]-5, 10, 10)

class Snake:
START_POS = (85, 85)
def __init__(self):
self.food = Food()
self.block_size = 11
self.x , self.y = self.START_POS
self.body = self.create_body()
# [...]
def checkForEat(self):
head = self.body[-1]
head_rect = pygame.Rect(head[0]-5, head[1]-5, self.block_size, self.block_size)

food_rect = self.food.getRect()

if food_rect.colliderect(head_rect):
self.food = Food()
self.eat()

另请参阅如何在pygame中检测碰撞？。

---

或者，您可以计算圆的圆心之间的欧几里得距离，并将该距离与半径之和进行比较：

class Snake:
# [...]
def checkForEat(self):
dx = self.food.getPos()[0] - self.body[-1][0]
dy = self.food.getPos()[1] - self.body[-1][1]
dist_center = math.hypot(dx, dy)
if dist_center <= 20:
self.food = Food()
self.eat()