Question

我试图在我的游戏中测试碰撞，这是一个Brick Breaker类型的游戏，在子弹和特定类型的砖之间。当子弹击中砖块时，然后移除砖块。我可以测试任何砖块和子弹之间的碰撞，并将它们移除。但我不能让碰撞在特定类型的砖之间工作，然后移除那块砖。

这是我的Brick.h课程

#import <SpriteKit/SpriteKit.h>

typedef enum : NSUInteger {
    // Normal Bricks
    Blue = 1,
    LightBlue = 2,
    DarkBlue = 3,
    Green = 4,
    LightGreen = 5,
    DarkGreen = 6,
    Grey = 7,
    DarkGrey = 8,
    Pink = 9,
    LightPink = 10,
    Purple = 11,
    LightPurple = 12,
    DarkPurple = 13,
    Red = 14,
    DarkRed = 15,
    Orange = 16,
    Gold = 17,
    Yellow = 18,
    Teal = 19,
    Brown = 20,
} BrickType;

static const uint32_t BRICK_CATEGORY = 0x1 << 2;

@interface XSBrick : SKSpriteNode

@property (nonatomic) BrickType type;
@property (nonatomic) BOOL indestructible;
@property (nonatomic) BOOL spawnsExtraBall;
@property (nonatomic) BOOL givesExtraLife;
@property (nonatomic) BOOL enlargePaddle;
@property (nonatomic) BOOL spawnsTwoOrThreeExtraBalls;
@property (nonatomic) BOOL makesBallSlow;
@property (nonatomic) BOOL makesBallFast;
@property (nonatomic) BOOL bullets;

-(instancetype)initWithType:(BrickType)type;
-(void)hit;

@end

Brick.m类

#import "XSBrick.h"

@implementation XSBrick
{
    SKAction *_brickSmashSound;
}

#pragma mark - Load Bricks
-(instancetype)initWithType:(BrickType)type
{
    switch (type) {
        // Normal Bricks
        case Blue:
            self = [super initWithImageNamed:@"BrickBlue"];
            break;

        case LightBlue:
            self = [super initWithImageNamed:@"BrickLightBlue"];
            break;

        case DarkBlue:
            self = [super initWithImageNamed:@"BrickDarkBlue"];
            break;

        case Green:
            self = [super initWithImageNamed:@"BrickGreen"];
            break;

        case DarkGreen:
            self = [super initWithImageNamed:@"BrickDarkGreen"];
            break;

        case LightGreen:
            self = [super initWithImageNamed:@"BrickLightGreen"];
            break;

        case Grey:
            self = [super initWithImageNamed:@"BrickGrey"];
            break;

        case DarkGrey:
            self = [super initWithImageNamed:@"BrickDarkGrey"];
            break;

        case Pink:
            self = [super initWithImageNamed:@"BrickPink"];
            break;

        case LightPink:
            self = [super initWithImageNamed:@"BrickLightPink"];
            break;

        case Purple:
            self = [super initWithImageNamed:@"BrickPurple"];
            break;

        case LightPurple:
            self = [super initWithImageNamed:@"BrickLightPurple"];
            break;

        case DarkPurple:
            self = [super initWithImageNamed:@"BrickDarkPurple"];
            break;

        case Red:
            self = [super initWithImageNamed:@"BrickRed"];
            break;

        case DarkRed:
            self = [super initWithImageNamed:@"BrickDarkRed"];
            break;

        case Orange:
            self = [super initWithImageNamed:@"BrickOrange"];
            break;

        case Gold:
            self = [super initWithImageNamed:@"BrickGold"];
            break;

        case Yellow:
            self = [super initWithImageNamed:@"BrickYellow"];
            break;

        case Teal:
            self = [super initWithImageNamed:@"BrickTeal"];
            break;

        case Brown:
            self = [super initWithImageNamed:@"BrickBrown"];
            break;

        default:
            self = nil;
            break;
    }

    return self;
}

在MyScene.m中，didBeginContact。这可以工作但删除子弹击中的任何类型的砖

// Collision between bullets and bricks
    if (firstBody.categoryBitMask == BRICK_CATEGORY && secondBody.categoryBitMask == BULLET_CATEGORY) {
        [firstBody.node removeFromParent];
        [secondBody.node removeFromParent];
    }

我试过了，但是Xcode给了我一个关于SKNode和NSUInteger之间比较的警告，所以它没有用。

// Collision between bullets and bricks
    if (firstBody.categoryBitMask == BRICK_CATEGORY && secondBody.categoryBitMask == BULLET_CATEGORY) {
        if (firstBody.node == LightBlue) {
            [firstBody.node removeFromParent];
        }
        [secondBody.node removeFromParent];
    }

我也尝试过创建我的Brick的一个实例然后针对它进行测试，但这也不起作用。

// Collision between bullets and bricks
    if (firstBody.categoryBitMask == BRICK_CATEGORY && secondBody.categoryBitMask == BULLET_CATEGORY) {
        XSBrick *LightBlueBrick = [[XSBrick alloc]initWithType:LightBlue];
        if (firstBody.node == LightBlueBrick) {
            [firstBody.node removeFromParent];
        }
        [secondBody.node removeFromParent];
    }

我已经有一段时间了，现在试图让它发挥作用。另外，我对iOS的开发还很陌生，所以任何帮助都会非常感激。

修改

我尝试了你的答案，rickster，但它犯了一个错误，“2014-07-02 09：13：52.527 Brick Breaker [44129：60b] - [SKSpriteNode type]：无法识别的选择器发送到实例0x12145a2a0”。但我确实使用你提供的一些代码让它工作。

// Collision between bullets and bricks
if (firstBody.categoryBitMask == BRICK_CATEGORY && secondBody.categoryBitMask == BULLET_CATEGORY) {
    XSBrick *brick = nil;
    SKNode *bullets = nil;
    if ([firstBody.node isKindOfClass:[XSBrick class]]) {
        brick = firstBody.node;
        bullets = secondBody.node;
        if (brick.type == LightBlue) {
            [firstBody.node removeFromParent];
        }
        else if (brick.type == Blue) {
            [firstBody.node removeFromParent];
        }
    }
    [secondBody.node removeFromParent];
}

这现在有效。它会检测到什么类型的砖被击中，然后移除该砖。如果它不在我的if语句中，它就不会被删除，这就是我想要的方式。非常感谢你的帮助!!

Answer 1

if (firstBody.node == LightBlue)无法正常工作，因为您正在将节点（对象指针）与枚举值（整数）进行比较。您需要比较相同类型的值以进行相等比较，以获得任何有用的含义。

if (firstBody.node == LightBlueBrick)无法正常工作，因为您正在针对您在那里创建的XSBrick实例进行测试。您已经在didBeginContact，因此已经存在的一个节点参与了碰撞 - 如果您创建了一个新节点，那么该节点将保证不会是那个节点。已经存在。您只需要检查碰撞中每个节点的属性，以找出它是哪个节点或哪种节点。

您已经有一个if语句，用于测试firstBody.categoryBitMask是否与您用于砖块的值相匹配。如果您确定将仅值用于砖块，则可以放心地假设firstBody.node指向XSBrick的实例。（但安全的做法是使用isKindOfClass来确定。）

要让编译器调用XSBrick方法，您需要将firstBody.node强制转换为该类类型。然后，您可以查看您在type上定义的XSBrick媒体资源。

最后，SpriteKit并不能保证联系人处理程序中主体的顺序，所以在砖块和子弹之间碰撞的第一个主体是砖块时，它永远不会是真的。

这些是解决此问题所需的成分。将它们放在一起，这是联系处理程序的示例实现：

- (void)didBeginContact:(SKPhysicsContact *)contact {
    // If we expect more than one kind of collision, check that first
    if (contact.bodyA.categoryBitMask | contact.bodyA.categoryBitMask == BRICK_CATEGORY | BULLET_CATEGORY)
        // We know it's a brick/bullet collision, sort out which body is which
        XSBrick *brick = nil;
        SKNode *bullet = nil;
        if ([contact.bodyA.node isKindOfClass:[XSBrick class]]) {
            brick = contact.bodyA.node;
            bullet = contact.bodyB.node;
        } else  {
            brick = contact.bodyB.node;
            bullet = contact.bodyA.node;
        }

        // Now, check the type of brick
        if (brick.type == LightBlue) {
            // Do whatever with light blue bricks
        } else {
            // Do whatever with other kinds of bricks
        }
    }
}

检查SpriteKit中节点和实例类型之间的冲突

1 个答案: