SKSpriteNode 无法检测到与两个 bodyWithEdgeLoopF​​romPath 主体的碰撞

Posted 2023-03-08

【中文标题】SKSpriteNode 无法检测到与两个 bodyWithEdgeLoopF​​romPath 主体的碰撞

【英文标题】：SKSpriteNode can't detect collision with two bodyWithEdgeLoopFromPath bodies

【发布时间】：2015-01-30 03:19:10

【问题描述】：

我使用 bodyWithEdgeLoopF​​romPath 创建了两个对象。但是当我通过方法检查碰撞时 - (void)didBeginContact:(SKPhysicsContact *)contact。它不工作。

对象 1： UIBezierPath *paddleLeftPath = [UIBezierPath bezierPath];

[paddleLeftPath moveToPoint:CGPointMake(-19,17)];
[paddleLeftPath addLineToPoint:CGPointMake(20,17)];
[paddleLeftPath addLineToPoint:CGPointMake(10,6)];
[paddleLeftPath addLineToPoint:CGPointMake(17,-7)];
[paddleLeftPath addLineToPoint:CGPointMake(6,-19)];
[paddleLeftPath addLineToPoint:CGPointMake(-6,-20)];
[paddleLeftPath addLineToPoint:CGPointMake(-17,-11)];
[paddleLeftPath addLineToPoint:CGPointMake(-13,6)];

[paddleLeftPath closePath];

objectRocket = [[NodeRocket alloc] initWithWithFile:@"main0.png" scale:0.5 atPosition:CGPointMake(CGRectGetMidX(self.frame),110)];
objectRocket.name = @"Rocket";
objectRocket.physicsBody.dynamic = NO;
objectRocket.physicsBody.usesPreciseCollisionDetection = YES;
objectRocket.physicsBody.categoryBitMask = rocketCategory;
objectRocket.physicsBody.collisionBitMask =  meteorCategory;
objectRocket.physicsBody.contactTestBitMask =  meteorCategory;
objectRocket.zPosition = 10;
objectRocket.physicsBody.allowsRotation = NO;
[self addChild:objectRocket];    

对象 2： SKNode* meteorPair = [SKNode 节点]; meteorPair.position = CGPointMake(0, 0); 流星对.zPosition = 10;

    NSInteger scaleValue = (arc4random() % 8) + 1;

    meteorTexture = [SKTexture textureWithImageNamed:[NSString stringWithFormat:@"monster%d.png",(int)scaleValue]];

    [meteorTexture setFilteringMode:SKTextureFilteringNearest];

    if (pointDrop.x > self.size.width - meteorTexture.size.width/2 - 10)
    
        pointDrop.x = self.size.width - meteorTexture.size.width/2 - 10;
    
    else if (pointDrop.x < meteorTexture.size.width/2 + 10)
    
        pointDrop.x = meteorTexture.size.width/2 + 10;
    

    CGFloat x = (arc4random() % 2) + 0.5;

    CGFloat distanceToMove = self.frame.size.height - 115 - objectUFO.size.height/2;
    SKAction* moveMeteor = [SKAction moveByX:0 y:-distanceToMove duration:x/100.0 * distanceToMove];
    SKAction* removeMeteor = [SKAction removeFromParent];
    moveMeteorAndRemove = [SKAction sequence:@[moveMeteor, removeMeteor]];

    SKSpriteNode* meteorObject = [SKSpriteNode spriteNodeWithTexture:meteorTexture];
    [meteorObject setScale:0.55];
    meteorObject.position = CGPointMake(pointDrop.x, pointDrop.y - objectUFO.size.height/2 );

    UIBezierPath *paddleLeftPath = [UIBezierPath bezierPath];

    [paddleLeftPath moveToPoint:CGPointMake(-22,28)];
    [paddleLeftPath addLineToPoint:CGPointMake(21,28)];
    [paddleLeftPath addLineToPoint:CGPointMake(17,-30)];
    [paddleLeftPath addLineToPoint:CGPointMake(-18,-30)];
    [paddleLeftPath closePath];
    meteorObject.name = [NSString stringWithFormat:@"monster%d.png",(int)scaleValue];
    meteorObject.physicsBody.dynamic = NO;
    meteorObject.physicsBody.usesPreciseCollisionDetection = YES;
    meteorObject.physicsBody.categoryBitMask = meteorCategory;        
    [meteorPair addChild:meteorObject];

    [meteorPair runAction:moveMeteorAndRemove];
    meteorPair.name = @"meteor pair";

    [self addChild:meteorPair];
     meteorObject.physicsBody = [SKPhysicsBody bodyWithEdgeLoopFromPath:paddleLeftPath.CGPath];    

请帮助我。我做错了什么？

【问题讨论】：

查看文档，两个静态（基于边缘）的物体永远不会产生碰撞。同样使用移动动作绕过物理模拟，使用 applyImpulse/Force 来移动动态物理体。

我让物体meteorObject坠落到与objectRocket发生碰撞。但是方法 didBeginContact 不起作用。

我将 bodyWithEdgeLoopF​​romPath 更改为 bodyWithPolygonFromPath。和meteorObject.physicsBody.dynamic = YES。他们可能会发生冲突，但方法 didBeginContact 仍然无法正常工作。

你设置了collisionDelegate吗？还要检查类别等位掩码，它们经常被误解，它们必须双向（即流星和火箭在一个主体中，火箭和流星在另一个主体中 - 仅省略其中一个位掩码不会产生碰撞）。

【参考方案1】：

你为 SKScene 的物理世界设置了 contactDelegate 了吗？也许您错过了它，然后 didBeginContact 从未被调用过。 在你的游戏场景上试试这个

self.physicsWorld.contactDelegate = self

【参考方案2】：

看起来你在分配物理体之前设置了一堆参数。

我是 SKPhysics 的新手，但从所有示例中可以看出，当您创建节点时，它带有一个 nil/null 物理体。

要明确。 SKSpriteNode* meteorObject = [SKSpriteNode spriteNodeWithTexture: ... meteorObject.physicsBody.dynamic = NO; meteorObject.physicsBody.usesPreciseCollisionDetection = YES； meteorObject.physicsBody.categoryBitMask = meteorCategory; ... meteorObject.physicsBody = [SKPhysicsBody bodyWithEdgeLoopF​​romPath:

必须是：-

SKSpriteNode*meteorObject = [SKSpriteNode spriteNodeWithTexture: ... meteorObject.physicsBody = [SKPhysicsBody bodyWithEdgeLoopF​​romPath: meteorObject.physicsBody.dynamic = NO; meteorObject.physicsBody.usesPreciseCollisionDetection = YES； meteorObject.physicsBody.categoryBitMask = meteorCategory; ...