这实际上就是问题的全部，在较早的版本中，跳转功能有效，但是由于在pygame窗口中为sprite添加了固定边框，因此它不再能够跳转，这里是完整的代码，尽管其中大多数无关紧要，请注意变量名称和含义：
#Imports
import pygame
import sys
import math
#Pygame Initialisation
pygame.init()
windowWidth=500
windowHeight=500
win = pygame.display.set_mode((windowWidth, windowHeight))
pygame.display.set_caption("ScreenShove WIP")
#Movement Initialisation ((c) means constant)
x=250 #X Position
y=434 #Y Position
dx=0 #Perceived Change in X
dy=0 #Perceived Change in Y
width=40 #Character Width (c)
height=60 #Character Height (c)
ax=3 #X axis acceleration (c)
ay=20 #Y axis acceleration (c)
xprev=0 #Previous X Position
yprev=0 #Previous Y Position
isJump=False#Is the sprite performing a jump?
dylock=0 #Counts the number of frames dy has been 0 in a jump
border=5 #Border size (c)
run = True
while run:
pygame.time.delay(20) #50 ish fps
#Add 1 indentation for all the following lines
#Exit Check
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
#Get Keypresses
keys = pygame.key.get_pressed()
#Y Movement Decay
assumeddx=x-xprev #Recalculates "dx" based on previous positions.
assumeddy=y-yprev #Recalculates "dy" based on previous positions.
xprev=x #Fixes "xprev" and "yprev" for the next frame.
yprev=y
if isJump == True: #If the sprite is performing a jump:
if keys[pygame.K_s] and y<windowHeight-height-border: #If the "s" key is pressed:
dy+=math.ceil(ay/2) #Increase the change in Y by half the Y axis acceleration constant
if assumeddy==0 or dy==0: #If the calculated or perceived change in Y is 0:
if dylock>=2: #If the change in Y is equal to 0 at least twice this jump:
isJump=False #Declare the sprite has finished performing a jump
dylock=0 #Reset the counter
dy=0 #Set the perceived change in Y to 0
else: #Otherwise:
dylock+=1 #Increase the counter by 1
dy+=1 #Increase the perceived change in Y by 1.
else: #Otherwise:
dy=0 #Set the perceived chnage in Y to 0.
#X Movement Decay
if dx>0: #If the perceived change in X is positive:
dx-=1 #Reduce it by 1
if dx<0: #If the perceived change in X is negative:
dx+=1 #Increase it by 1
#User Movement Changes
if keys[pygame.K_a] and x>=dx+border and dx>-10: #If the "a" key is pressed and the sprite is in a valid position and the change in X exceeds -10:
dx-=ax #Reduce the change in X by the X axis acceleration constant
elif keys[pygame.K_d] and x<windowWidth-width-border and dx<10: #If the "d" key is pressed and the sprite is in a valid position and the change in X does not exceed 10:
dx+=ax #Increase the change in X by the X axis acceleration constant
if keys[pygame.K_w]: #If the "w" key is pressed:
if y >= dy+border and isJump==False and jumplock==False: #If the sprite is in a valid position, is not performing a jump already and the jump key isn't locked:
dy-=ay #Decrease the change in Y by the Y axis acceleration constant
isJump = True #Declare the sprite is performing a jump.
jumplock=True #Lock the jump key.
else: #Otherwise:
jumplock=False #Unlock the jump key.
#Border Fix for Velocity
if dx<0: #If the change in X is positive
if x>=-dx+border: #If the sprite is in a valid position
x+=dx #Increase the X position by the change in X
else: #Otherwise:
dx=0 #Set the change in X to 0
x=border #Set the X position to the nearest valid X position
if dx>0:
if x<=windowWidth-width-border:
x+=dx
else:
dx=0
x=windowWidth-width-border
if dy>0:
if y<=windowHeight-height-border:
y+=dy
else:
dy=0
y=windowHeight-height-border
#Border Fix for Position
if x<0+border:
x=border
if x>windowWidth-width-border:
x=windowWidth-width-border
if y>windowHeight-height-border:
y=windowHeight-height-border
#Debugging
print("P:",x,y)
print("V:",dx,dy)
print("Jumping:",str(isJump))
print("Jump Locked:",str(jumplock))
#Draw to Screen
win.fill((0,0,0))
pygame.draw.rect(win, (0, 200 ,0), (x,y,width,height))
pygame.display.update()
#No more indentations
#Exit
pygame.quit()
sys.exit()
除了这里的代码外，还有我尝试启动跳转期间的自制调试日志：
P: 250 434
V: 0 0
Jumping: False
Jump Locked: False
P: 250 434
V: 0 -20
Jumping: True
Jump Locked: True
P: 250 434
V: 0 -19
Jumping: True
Jump Locked: True
P: 250 434
V: 0 -18
Jumping: True
Jump Locked: False
P: 250 435
V: 0 1
Jumping: False
Jump Locked: False
P: 250 435
V: 0 0
Jumping: False
Jump Locked: False
P表示位置。
V表示速度或位置变化。
两者均以“ X Y”给出。
跳跃是布尔值“ isJump”， 跳转锁定是布尔值“ jumplock”。
答案 0 :(得分：0)
代替这样做：
if dy>0:
if y<=windowHeight-height-border:
y+=dy
else:
dy=0
y=windowHeight-height-border
我应该这样做：
if y<=windowHeight-height-border:
y+=dy
elif dy>0:
dy=0
y=windowHeight-height-border
因为dy并不总是正值（Tom也不行）。
事实证明，这与我删除了窗口的上限有关，因此跳线不会在窗口的天花板处被遮盖。