didBeginContact：（SKPhysicsContact *）contact not invoked

Question

我创建了SKScene继承类。 问题是，在物理体的方法的接触

- (void)didBeginContact:(SKPhysicsContact *)contact 

不调用 溶液可以是简单但与精灵套件初学者我坚持此。

下面是代码提前

#import "MyScene.h" 
@interface MyScene() 
@property BOOL contentCreated; 
@end 
@implementation MyScene 
- (id)initWithSize:(CGSize)size { 
    self = [super initWithSize:size]; 
    if (self) { 
     self.physicsWorld.contactDelegate = self; 
     self.physicsBody = [SKPhysicsBody bodyWithEdgeLoopFromRect:self.frame]; 
    } 
    return self; 
} 
- (void)didMoveToView:(SKView *)view 
{ 
    if (!self.contentCreated) { 
     [self buildWorld]; 
     self.physicsWorld.contactDelegate = self; 
    } 
} 

#pragma mark - World Building 
- (void)buildWorld { 
    NSLog(@"Building the world"); 
    SKSpriteNode * sprite1 = [[SKSpriteNode alloc] initWithColor:[SKColor grayColor] size:CGSizeMake(100,100)]; 
    sprite1.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:CGSizeMake(100,100)]; 
    sprite1.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame) +100); 

    SKSpriteNode * sprite2 = [[SKSpriteNode alloc] initWithColor:[SKColor grayColor] size:CGSizeMake(100,100)]; 
    sprite2.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:CGSizeMake(100,100)]; 
    sprite2.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame) - 100); 


    [self addChild:sprite1]; 
    [self addChild:sprite2]; 
} 
- (void)didBeginContact:(SKPhysicsContact *)contact 
{ 
    NSLog(@"contact"); 
} 

@end 

感谢。

Answer 1

从SKPhysicsWorld文档：

当两个物理机构重叠和 物理机构之一具有contactTestBitMask性质与 其他机构的categoryBitMask财产重叠创建联系人。

您必须指定物理实体categoryBitMask和contactTestBitMask。您需要先创建您的类别：

static const uint32_t sprite1Category = 0x1 << 0; 
static const uint32_t sprite2Category = 0x1 << 1; 

接下来，分配类别和接触式测试位掩码：

sprite1.physicsBody.categoryBitMask = sprite1Category; 
sprite1.physicsBody.contactTestBitMask = sprite2Category; 

sprite2.physicsBody.categoryBitMask = sprite2Category; 
sprite2.physicsBody.contactTestBitMask = sprite1Category; 

注意从SKPhysicsBody文档：

为了获得最佳性能，只在联系人掩码中设置 您有兴趣的互动位。