如何在spriteKit上触摸旋转图像/精灵？

Question

我试图用一个手指触摸使精灵旋转。 老实说，我不知道该怎么做，这是spriteKit的新功能。 有任何想法吗？

Answer 1

这会将子画面旋转到您使用动作触摸的位置。 如果您希望它在拖动手指时旋转。 您应该删除操作，然后对touchesMoved:进行计算。

-(void)didMoveToView:(SKView *)view {
    sprite = [SKSpriteNode spriteNodeWithImageNamed:@"Spaceship"];

    sprite.xScale = 0.5;
    sprite.yScale = 0.5;
    sprite.position = CGPointMake(self.frame.size.width / 2, self.frame.size.height/2);

    [self addChild:sprite];
}

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    for (UITouch *touch in touches) {
        CGPoint location = [touch locationInNode:self];


        float dY = sprite.position.y - location.y;
        float dX = sprite.position.x - location.x;
        float angle = atan2f(dY, dX) + 1.571f;
        [sprite runAction:[SKAction rotateToAngle:angle duration:0.5 shortestUnitArc:YES]];
        return;
    }
}

或者：（请记住，要从touchesBegan:删除代码开始touchesBegan:

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
    for (UITouch *touch in touches) {
        CGPoint location = [touch locationInNode:self];

        float dY = sprite.position.y - location.y;
        float dX = sprite.position.x - location.x;
        float angle = (atan2f(dY, dX)) + 1.571f;
        sprite.zRotation = angle;
    }
}