投影对象的动画使用 pygame

Question

我正在尝试制作投影运动的动画，但它不起作用。 只出现一个黑色窗口。

import math
import time
import pygame

V0 = int(input("please enter initial speed(m/s)"))
angle = int(input("please enter throwing angle"))
BLACK = (0, 0, 0)
WHITE = (255, 255, 255)

pygame.init()
screen = pygame.display.set_mode((400, 300))
done = False
clock = pygame.time.Clock()

while not done:
    T = time.clock()
    x = int(math.cos(angle)*V0*T)
    y = int((math.sin(angle)*V0*T)-1/2*(9.8*T*T))
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            done = True
    screen.fill(BLACK)
    pygame.draw.circle(screen, WHITE, (x, y), 5, 0)

    pygame.display.flip()
    clock.tick(10)

pygame.quit()

我认为问题在于我的公式语句，但我不知道如何解决它。

Answer 1

阅读 cmets。我改变了你计算时间和角度的方式。

import math
import time
import pygame

V0 = int(input("please enter initial speed(m/s)"))
angle = int(input("please enter throwing angle"))
BLACK = (0, 0, 0)
WHITE = (255, 255, 255)

pygame.init()
screen = pygame.display.set_mode((400, 300))
done = False
clock = pygame.time.Clock()
T = 0 #initialize

while not done:
    #T = time.clock() #don't use

    x = int(math.cos(math.radians(angle))*V0*T) #use math.radians(degree). Don't just provide degrees. cos() and sin() needs input in radians
    y = 300 - int((math.sin(math.radians(angle))*V0*T)-(0.5*9.8*T*T)) #looks better. projectile starts from the ground.

    for event in pygame.event.get():
    if event.type == pygame.QUIT:
        done = True
    screen.fill(BLACK)
    pygame.draw.circle(screen, WHITE, (x,y), 5, 0)

    milliseconds = clock.tick(60)   #try this. count ms. add to s. calculate total time passed.
    seconds = milliseconds / 1000.0 
    T += seconds

    pygame.display.flip()

pygame.quit()