子弹不能在鼠标的精确位置射击:(

时间:2015-10-19 18:24:15

标签: python pygame

所以我正在用pygame写一个游戏,玩家逃离僵尸街区并开枪杀死他们。我的子弹朝我的鼠标位置射击,这就是我想要的。然而,子弹似乎只能从大约10个不同的轴上射击。而不是360度圆圈中的任何地方。我如何解决这个问题,以便子弹总是直接指向鼠标光标而不是靠近它?

- 这是我的整个程序,所以你可以复制/粘贴它来试试游戏。注意子弹是如何完全不遵循鼠标位置的。怎么解决这个问题?子弹的代码将发布在整个游戏代码下方。 WASD移动,鼠标瞄准和射击,按下' P'退出:

import pygame
import math
import random

BLACK  = (0, 0, 0)
WHITE  = (255, 255, 255)
GREEN  = (0, 255, 0)
RED    = (255, 0, 0)
BLUE   = (0, 0, 255)
ORANGE = (255, 119, 0)
ZOMBIE_GREEN = (122, 172, 34)

cursor_x = 100
cursor_y = 100

class Player(pygame.sprite.Sprite):

    def __init__(self, color):
        super().__init__()

        # pygame.Surface will create a rectangle with the width and height given
        # and the command below it tells it to fill it in with that color
        self.image = pygame.Surface([15, 15])
        self.image.fill(color)
        self.rect = self.image.get_rect()

        # This defines the starting position (x, y)
        # of whatever sprite is passed through
        self.rect.x = 600
        self.rect.y = 300

        # This is the current speed it will move when drawn
        self.change_x = 0
        self.change_y = 0
        self.walls = None

    # Defines how the player will move
    def movement(self, x, y):
        self.change_x += x
        self.change_y += y


    # Updates the information so the screen shows the player moving
    def update(self):
        self.rect.x += self.change_x
        # Did this update cause us to hit a wall?
        block_hit_list = pygame.sprite.spritecollide(self, self.walls, False)
        for block in block_hit_list:
            # If we are moving right, set our right side to the left side of
            # the item we hit
            if self.change_x > 0:
                self.rect.right = block.rect.left
            else:
                # Otherwise if we are moving left, do the opposite.
                self.rect.left = block.rect.right

        self.rect.y += self.change_y
        # Check and see if we hit anything
        block_hit_list = pygame.sprite.spritecollide(self, self.walls, False)
        for block in block_hit_list:

            # Reset our position based on the top/bottom of the object.
            if self.change_y > 0:
                self.rect.bottom = block.rect.top
            else:
                self.rect.top = block.rect.bottom

class Enemy(pygame.sprite.Sprite):
    def __init__(self, color):
        super().__init__()
        self.image = pygame.Surface([20, 20])
        self.image.fill(color)
        self.rect = self.image.get_rect()
        self.rect.x = random.randrange(35, screen_width - 35)
        self.rect.y = random.randrange(35, screen_height - 135)
        self.change_x = 0
        self.change_y = 0
        self.walls = None

    def movement(self, x, y):
        self.change_x += x
        self.change_y += y

class Wall(pygame.sprite.Sprite):

    def __init__(self, color, x, y, width, height):
        super().__init__()

        self.image = pygame.Surface([width, height])
        self.image.fill(color)

        self.rect = self.image.get_rect()

        self.rect.x = x
        self.rect.y = y

class Cursor(pygame.sprite.Sprite):

    def __init__(self, width, height):
        super().__init__()

        self.image = pygame.Surface([width, height])
        self.image.fill(RED)

        self.rect = self.image.get_rect()
        self.walls = None

    # This updates the cursor to move along with your
    # mouse position (defined in control logic)
    def update(self):
        self.rect.x = cursor_x
        self.rect.y = cursor_y

class Bullet(pygame.sprite.Sprite):

    def __init__(self):
        super().__init__()

        self.image = pygame.Surface([8, 8])
        self.image.fill(ORANGE)
        self.rect = self.image.get_rect()

        self.rect.x = player.rect.x + 4
        self.rect.y = player.rect.y + 4

        self.walls = None
        self.change_x = 0
        self.change_y = 0

    def bullet_movement(self, cursor_pos_x, cursor_pos_y, player_pos_x, player_pos_y):
        bullet_vec_x = cursor.rect.x - player.rect.x
        bullet_vec_y = cursor.rect.y - player.rect.y
        vec_length = math.sqrt(bullet_vec_x ** 2 + bullet_vec_y ** 2) # Normalizing the Vector
        bullet_vec_x = (bullet_vec_x / vec_length) * 5 # These numbers determine how
        bullet_vec_y = (bullet_vec_y / vec_length) * 5 # fast the bullets travel
        self.change_x += bullet_vec_x
        self.change_y += bullet_vec_y

    def update(self):
        self.rect.x += self.change_x
        self.rect.y += self.change_y

pygame.init()

screen_size = pygame.display.Info()

#size = (900, 700)
#screen = pygame.display.set_mode(size)

size = (screen_size.current_w, screen_size.current_h)
screen = pygame.display.set_mode(
    ((screen_size.current_w, screen_size.current_h)),pygame.FULLSCREEN
    )

screen_width = screen_size.current_w
screen_height = screen_size.current_h

pygame.display.set_caption("Zombie Shooter")



wall_list = pygame.sprite.Group()
sprites_list = pygame.sprite.Group()
bullet_list = pygame.sprite.Group()
all_sprites_list = pygame.sprite.Group()

# Walls are made here = (x_coord for where it starts,
# y_coord for where it starts, width of wall, height of wall)
# These walls are made with fullscreen dimentions, not any set dimentions
# Left
wall = Wall(BLUE, 0, 0, 10, screen_height)
wall_list.add(wall)
all_sprites_list.add(wall)
# Top
wall = Wall(BLUE, 0, 0, screen_width, 10)
wall_list.add(wall)
all_sprites_list.add(wall)
# Bottom
wall = Wall(BLUE, 0, screen_height - 10, screen_width, 10)
wall_list.add(wall)
all_sprites_list.add(wall)
# Right
wall = Wall(BLUE, screen_width - 10, 0, 10, screen_width)
wall_list.add(wall)
all_sprites_list.add(wall)
# HUD Border
wall = Wall(BLUE, 0, screen_height - 100, screen_width, 10)
wall_list.add(wall)
all_sprites_list.add(wall)

# This creates the actual player with the parameters set in ( ).
# However, we must add the player to the all_sprites_list
# so that it will actually be drawn to the screen with the draw command
# placed right after the screen.fill(BLACK) command.
player = Player(WHITE)
player.walls = wall_list
all_sprites_list.add(player)

cursor = Cursor(7, 7)
cursor.walls = wall_list
all_sprites_list.add(cursor)

zombie = Enemy(ZOMBIE_GREEN)
for i in range(10):
    zombie = Enemy(ZOMBIE_GREEN)
    all_sprites_list.add(zombie)
    sprites_list.add(zombie)

bullet = Bullet()




done = False

clock = pygame.time.Clock()

pygame.mouse.set_visible(0)

# -------- Main Program Loop -----------
while not done:

    # --- Main event loop ---
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            done = True
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_p:
                done = True

        # Keyboard controls. The numbers inside change the speed of the player
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_a:
                player.movement(-4, 0)
            elif event.key == pygame.K_d:
                player.movement(4, 0)
            elif event.key == pygame.K_w:
                player.movement(0, -4)
            elif event.key == pygame.K_s:
                player.movement(0, 4)

        elif event.type == pygame.KEYUP:
            if event.key == pygame.K_a:
                player.movement(4, 0)
            elif event.key == pygame.K_d:
                player.movement(-4, 0)
            elif event.key == pygame.K_w:
                player.movement(0, 4)
            elif event.key == pygame.K_s:
                player.movement(0, -4)

        pos = pygame.mouse.get_pos()
        cursor_x = pos[0]
        cursor_y = pos[1]

        if cursor_x <= 10:
            cursor_x = 10
        if cursor_x >= (screen_width - 17):
            cursor_x = (screen_width - 17)

        if cursor_y <= 10:
            cursor_y = 10
        if cursor_y >= (screen_height - 107):
            cursor_y = (screen_height - 107)

        elif event.type == pygame.MOUSEBUTTONDOWN:
            bullet = Bullet()
            all_sprites_list.add(bullet)
            bullet_list.add(bullet)
            bullet.bullet_movement(cursor.rect.x, cursor.rect.y, player.rect.x, player.rect.y)

    all_sprites_list.update()

    pygame.mouse.set_visible(0)

    for bullet in bullet_list:
        block_hit_list = pygame.sprite.spritecollide(bullet, sprites_list, True)
        for i in block_hit_list:
            bullet_list.remove(bullet)
            all_sprites_list.remove(bullet)

    for bullet in bullet_list:
        block_hit_list = pygame.sprite.spritecollide(bullet, wall_list, False)
        for i in block_hit_list:
            bullet_list.remove(bullet)
            all_sprites_list.remove(bullet)

    # .update() will 'update' or change the screen with what
    # we've told it to everytime we run throught the loop. Without
    # this our player would not appear to move on the screen because
    # we wouldn't be telling the screen to change the coordinates of the player.
    cursor.update()
    bullet_list.update()



    screen.fill(BLACK)

    all_sprites_list.draw(screen)

    pygame.display.flip()

    clock.tick(60)

pygame.quit()

这里是如何计算子弹矢量的。可以编辑它以使子弹更准确地朝向红色光标位置吗?

class Bullet(pygame.sprite.Sprite):

    def __init__(self):
        super().__init__()

        self.image = pygame.Surface([8, 8])
        self.image.fill(ORANGE)
        self.rect = self.image.get_rect()

        self.rect.x = player.rect.x + 4
        self.rect.y = player.rect.y + 4

        self.walls = None
        self.change_x = 0
        self.change_y = 0

    def bullet_movement(self, cursor_pos_x, cursor_pos_y, player_pos_x, player_pos_y):
        bullet_vec_x = cursor.rect.x - player.rect.x
        bullet_vec_y = cursor.rect.y - player.rect.y
        vec_length = math.sqrt(bullet_vec_x ** 2 + bullet_vec_y ** 2) # Normalizing the Vector
        bullet_vec_x = (bullet_vec_x / vec_length) * 5 # These numbers determine how
        bullet_vec_y = (bullet_vec_y / vec_length) * 5 # fast the bullets travel
        self.change_x += bullet_vec_x
        self.change_y += bullet_vec_y

    def update(self):
        self.rect.x += self.change_x
        self.rect.y += self.change_y

1 个答案:

答案 0 :(得分:0)

我怀疑这是一个整数数学问题。在某些角度,您为子弹计算的速度需要在给定方向上移动一小部分像素,但pygame.rect仅支持整数坐标。

我不确定Pygame的类型是如何实现的,但我怀疑这意味着每帧都会丢弃更新位置的小数部分。因为许多速度矢量以相同的方式变圆,所以最终会得到比你想要的角度更有限的角度。

解决方案是维护您自己的(浮点)位置值。您的更新代码会将速度组件添加到浮点位置值,然后将更新的值复制到pygame.rect坐标。通过这种方式,舍入误差不会累积,您可以看到不同向量之间的差异。

class Bullet(pygame.sprite.Sprite):

    def __init__(self):
        super().__init__()

        self.image = pygame.Surface([8, 8])
        self.image.fill(ORANGE)
        self.rect = self.image.get_rect()

        self.pos_x = player.rect.x + 4   # Set up pos_x and pos_y here
        self.pos_y = player.rect.y + 4   # rather than rect.x and rect.y

        self.walls = None
        self.change_x = 0
        self.change_y = 0

    def bullet_movement(self, cursor_pos_x, cursor_pos_y, player_pos_x, player_pos_y):
        bullet_vec_x = cursor.rect.x - player.rect.x
        bullet_vec_y = cursor.rect.y - player.rect.y
        vec_length = math.sqrt(bullet_vec_x ** 2 + bullet_vec_y ** 2)
        bullet_vec_x = (bullet_vec_x / vec_length) * 5
        bullet_vec_y = (bullet_vec_y / vec_length) * 5
        self.change_x += bullet_vec_x
        self.change_y += bullet_vec_y

    def update(self):
        self.pos_x += self.change_x  # Update pos_x and pos_y. They will become floats
        self.pos_y += self.change_y  # which will let them maintain sub-pixel accuracy.

        self.rect.x = self.pos_x  # Copy the pos values into the rect, where they will be
        self.rect.y = self.pos_y  # rounded off. That's OK since we never read them back.

此代码存在一些赔率区域,例如您根本不使用bullet_movement函数的参数,而只是查找全局值playercursor(您还可以在player方法中查找__init__)。我没有修改过这些,但是你可能想要,一旦你控制了舍入问题。我还考虑将bullet_movement中的代码合并到__init__,因为在没有设置其移动的情况下,您也不希望创建项目符号。< / p>