ios - 使用bodyWithPolygonFromPath:方法对蛋形进行声明时断言失败

Question

我正在将物理模拟为蛋形SKSprite节点。
但是，有断言失败的错误发生:

断言失败:(edge.LengthSquared()> 1.19209290e-7F * 1.19209290e-7F)，函数集，文件/SourceCache/PhysicsKit_Sim/PhysicsKit-6.5.4/PhysicsKit/Box2D/Collision/Shapes/b2PolygonShape.cpp，第180行。

以下是代码:

self.egg = [SKSpriteNode spriteNodeWithImageNamed:IMAGE_NAME_EGG];
    [self.egg setScale:0.2];
    self.egg.position = CGPointMake(self.size.width/2,self.size.height - self.egg.size.height/2);
    self.egg.name = IMAGE_NAME_EGG;

    CGPoint startPoint = CGPointMake(0, self.egg.size.height*0.4);
    CGPoint endPoint = CGPointMake(self.egg.size.width, startPoint.y);
    CGPoint controlPointLeft = CGPointMake(startPoint.x, self.egg.size.height);
    CGPoint controlPointRight = CGPointMake(endPoint.x, controlPointLeft.y);


    CGMutablePathRef pathRef = CGPathCreateMutable();        
    CGPathMoveToPoint(pathRef, NULL, startPoint.x, startPoint.y);
    CGPathAddQuadCurveToPoint(pathRef, NULL, controlPointLeft.x, controlPointLeft.y, self.egg.size.width/2, controlPointLeft.y);
    CGPathAddQuadCurveToPoint(pathRef, NULL, controlPointRight.x, controlPointRight.y, endPoint.x,endPoint.y);
    CGPathAddArc(pathRef, NULL, self.egg.size.width/2, startPoint.y, self.egg.size.width/2, 0, M_PI, NO);

    self.egg.physicsBody = [SKPhysicsBody bodyWithPolygonFromPath:pathRef];
    self.egg.physicsBody.dynamic = YES;
    self.egg.physicsBody.categoryBitMask = eggCategory;
    self.egg.physicsBody.contactTestBitMask = rabbitCategory;
    self.egg.physicsBody.collisionBitMask = rabbitCategory;
    self.egg.physicsBody.allowsRotation = YES;
    [self addChild:self.egg];

怎么了？谁能帮我修复？非常感谢你!

Answer 1

根据断言，边缘之一比sprite工具包预期的最小大小短。

Assertion failed: (edge.LengthSquared() > 1.19209290e-7F * 1.19209290e-7F)

检查您的路径坐标，并确保它不太小。