如何在PhysicsBody區域中檢測觸摸？

Question

我確實使用此代碼創建了SKSpriteNode，而physicsBody是圓形的。 我如何檢查用戶是否在PhysicsBody中觸摸耳朵？

self = [super initWithColor:[SKColor clearColor] size:CGSizeMake(200, 200)];
//...
self.physicsBody = [SKPhysicsBody bodyWithCircleOfRadius:self.size.width/2.0f];
self.userInteractionEnabled = YES;

Answer 1

我確實使用以下代碼找到了解決問題的方法：

CGMutablePathRef pathRef;
// Fill pathRef with points and create phisycs body using pathRef.

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [touches anyObject];
    CGPoint touchLocation = [touch locationInNode:self.scene];

    if (CGPathContainsPoint(pathRef, nil, touchLocation, NO)) {
        // If we are here it means user did touche physic body.
    }
}

Answer 2

最簡單的解決方案是創建第二個不可見的精靈，它具有所需的大小，並將其直接放在要記錄觸摸的區域上。

另一個選擇是存儲所有觸發有效觸摸的坐標，並將它們與您的觸摸方法中的實際觸摸坐標進行比較，如下所示：

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [touches anyObject];
    CGPoint touchLocation = [touch locationInNode:self.scene];

    NSLog(@"%@", NSStringFromCGPoint(touchLocation));
    // Compare the touchLocation coordinate against your list of acceptable coordinates...
}