Pygame三角学：位置抖动，移动目标时

Question

我在 Python 中遇到三角算法问题。我在一个小型自上而下的射击游戏上工作，我计算角度和旋转精灵的方式适用于我的玩家，我的子弹，但对于我的敌人（总是面对玩家），它做了一些奇怪的事情..

当玩家静止时它工作正常，但一旦玩家移动（并且角度改变），敌人就会在原地抖动，看起来每帧来回移动一到两个像素。我在代码中留下了调试打印，并将在问题期间附上一些控制台打印输出：

class Enemy:
    def __init__(self, x, y,):
        self.x = x
        self.y = y
        self.angle = 0
        self.speed = 2
        self.velX = 0
        self.velY = 0

        self.scoreVal = 10
        self.texture = pygame.image.load('char_terrorist.png')
        self.image = pygame.transform.rotate(self.texture, int(self.angle))

    def rotate(self):
        targetX, targetY = player1.x, player1.y
        relX, relY = targetX - self.x, targetY - self.y
        self.angle = (180 / math.pi) * math.atan2(relY, relX) 
        self.image = pygame.transform.rotate(self.texture, int(self.angle)*-1-90)
        self.rect = self.image.get_rect(center=(self.x, self.y))
        self.velX = self.speed * math.cos(self.angle)
        self.velY = self.speed * math.sin(self.angle)

        print()
        print('## ROTATE: velX, velY: ', self.velX, self.velY)
        print('## ROTATE ANGLE: ', self.angle)

    def move(self):
        print('## MOVE: velX: ', self.velX, '        velY: ', self.velY)
        self.x += self.velX
        self.y += self.velY 

    def render(self):
        imageRect = self.image.get_rect()
        imageRect.center = self.x, self.y
        playSurface.blit(self.image, imageRect)

以及控制台打印输出的一部分：

## ROTATE: velX, velY:  1.5033760962079608 1.31903764667674
## ANGLE:  -93.52760115485472
## MOVE: x, y:  158.34842803029636 374.5728764810448
## MOVE: velX, velY:  1.5033760962079608 1.31903764667674

## ROTATE: velX, velY:  -0.15199863628529925 -1.9942157392236701
## ANGLE:  -95.89464860414104
## MOVE: x, y:  158.19642939401106 372.5786607418211
## MOVE: velX, velY:  -0.15199863628529925 -1.9942157392236701

## ROTATE: velX, velY:  -1.6646141877222582 1.1086296072330768
## ANGLE:  -97.97691175203515
## MOVE: x, y:  156.5318152062888 373.6872903490542
## MOVE: velX, velY:  -1.6646141877222582 1.1086296072330768

## ROTATE: velX, velY:  1.2713600983706417 1.5439052756794998
## ANGLE:  -99.64905773569804
## MOVE: x, y:  157.80317530465945 375.2311956247337
## MOVE: velX, velY:  1.2713600983706417 1.5439052756794998

## ROTATE: velX, velY:  0.47746450045160277 -1.9421708603540784
## ANGLE:  -101.8607010982417
## MOVE: x, y:  158.28063980511104 373.28902476437963
## MOVE: velX, velY:  0.47746450045160277 -1.9421708603540784

## ROTATE: velX, velY:  1.743360387120541 0.9801502745084132
## ANGLE:  -100.01878896583855
## MOVE: x, y:  160.02400019223157 374.269175038888
## MOVE: velX, velY:  1.743360387120541 0.9801502745084132

## ROTATE: velX, velY:  -1.2224714556282295 1.5828971982331
## ANGLE:  -98.30254758732487
## MOVE: x, y:  158.80152873660333 375.85207223712115
## MOVE: velX, velY:  -1.2224714556282295 1.5828971982331

我注意到，velX 和 velY 计算错误，但角度似乎是正确的..我真的不知道如何更好地调试它，我现在盯着角度算法看了一会儿但不会得到正确的想法..

感谢大家的帮助！

Answer 1

如我在评论中所述，错误的原因是由于 degree 用于 math.sin() 和 math.cos()。

所以只需将它们改回弧度即可解决问题。

self.velX = self.speed * math.cos(self.angle * (math.pi /180))
self.velY = self.speed * math.sin(self.angle * (math.pi /180))

Pygame三角学：位置抖动，移动目标时

Pygame trigonometry: Position jittering, when moving target

python

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python-3.6