To move the tank in the direction which is faced, wirte a method, that computes a direction vector, dependent on an velocity
argument and the self.angle
attribute. The nagle and the velocity define a vector by Polar coordinats.
Add the vector to it's current position (self.pos). Finally update the self.rect
attribute by the position:
class Tank(pygame.sprite.Sprite):
# [...]
def move(self, velocity):
direction = pygame.Vector2(0, velocity).rotate(-self.angle)
self.pos += direction
self.rect.center = round(self.pos[0]), round(self.pos[1])
Invoke the method when up or down is pressed:
class Game:
# [...]
def handle_events(self):
# [...]
if keys[pygame.K_UP]:
self.tank.move(-5)
if keys[pygame.K_DOWN]:
self.tank.move(5)
The movement direction of the bullets can be computed similar:
class Bullet(pygame.sprite.Sprite):
def __init__(self, tank):
#[...]
self.rect = self.image.get_rect()
self.angle = tank.angle
self.pos = pygame.Vector2(tank.pos)
self.rect.center = round(self.pos.x), round(self.pos.y)
self.direction = pygame.Vector2(0, -10).rotate(-self.angle)
def update(self):
self.pos += self.direction
self.rect.center = round(self.pos[0]), round(self.pos[1])
To make the bullet bounce, you have to reflect the direction when the bullet hits a border:
class Bullet(pygame.sprite.Sprite):
# [...]
def update(self):
self.pos += self.direction
self.rect.center = round(self.pos.x), round(self.pos.y)
if self.rect.left < 0:
self.direction.x *= -1
self.rect.left = 0
self.pos.x = self.rect.centerx
if self.rect.right > 1060:
self.direction.x *= -1
self.rect.right = 1060
self.pos.x = self.rect.centerx
if self.rect.top < 0:
self.direction.y *= -1
self.rect.top = 0
self.pos.y = self.rect.centery
if self.rect.bottom > 798:
self.direction.y *= -1
self.rect.right = 798
self.pos.y = self.rect.centery
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