SKPhysics体路径生成器

Posted 2023-03-10

【中文标题】SKPhysics体路径生成器

【英文标题】：SKPhysicsBody Path Generator

【发布时间】：2015-03-30 17:11:46

【问题描述】：

我正在使用SKPhysicsBody Path Generator

为我的精灵生成polygonFromPath。问题是我需要一条有两个孔的路径，我该如何实现？

如下图所示，路径最多只能连接一个孔，但我需要两个孔！有什么帮助吗？

我也尝试了以下方法，但它崩溃了：

let path = CGPathCreateMutable()

        MoveToPoint(path, x: 51 , y:22 , node:sprite)
        AddLineToPoint(path, x: 38 , y:45 , node:sprite)
        AddLineToPoint(path, x: 32 , y:44 , node:sprite)
        AddLineToPoint(path, x: 32 , y:0 , node:sprite)
        AddLineToPoint(path, x: 39 , y:0 , node:sprite)

        let path2 = CGPathCreateMutable()

        MoveToPoint(path2, x: 0 , y:22 , node:sprite)
        AddLineToPoint(path2, x: 13 , y:0 , node:sprite)
        AddLineToPoint(path2, x: 19 , y:0 , node:sprite)
        AddLineToPoint(path2, x: 19 , y:45 , node:sprite)
        AddLineToPoint(path2, x: 13 , y:45 , node:sprite)

sprite.physicsBody = SKPhysicsBody(bodies: [path, path2])

【参考方案1】：

您不能将bodyWithPolygonFromPath 用于您想要的形状。 bodyWithPolygonFromPath 仅适用于凸多边形路径。

您可以使用bodyWithBodies:(NSArray *)bodies 在右侧和底部绘制两个三角形，在左上角绘制正方形。请记住，空白区域不会注册联系人。

这是一个例子：

SKSpriteNode node0 = [SKSpriteNode spriteNodeWithColor:[SKColor lightGrayColor] size:CGSizeMake(200, 200)];
node0.position = CGPointMake(400, 400);

SKPhysicsBody *firstBody = [SKPhysicsBody bodyWithRectangleOfSize:CGSizeMake(50, 50) center:CGPointMake(-75, 75)];
SKPhysicsBody *secondBody = [SKPhysicsBody bodyWithRectangleOfSize:CGSizeMake(200, 50) center:CGPointMake(0, -75)];
SKPhysicsBody *thirdBody = [SKPhysicsBody bodyWithRectangleOfSize:CGSizeMake(50, 150) center:CGPointMake(75, 26)];
node0.physicsBody = [SKPhysicsBody bodyWithBodies:@[firstBody, secondBody, thirdBody]];
node0.physicsBody.dynamic = NO;
[self addChild:node0];

【讨论】：

感谢您的回复 :) 我编辑了我的问题：我尝试了 SKPhysicsBody(bodies: [path, path2]) 但应用程序崩溃了。有什么帮助吗？

路径不是主体。您需要创建 2 个实体，然后使用它们来创建第三个实体。

@Fogmeister 正如文档中所写，它是一个 AnyObject 数组：init(bodies body: [AnyObject]) -> SKPhysicsBody 所以我不能将路径添加为数组元素？

@Fogmeister 好的，我读了更多然后我明白了：bodys SKPhysicsBody 对象的数组。谢谢

@sangony 谢谢我解决了请检查我的答案如果您对我的答案有任何反馈，请随时告诉我，我很乐意改进我的代码。

【参考方案2】：

好的，我解决了它:)

让 sprite = SKSpriteNode(imageNamed: "cell3")

sprite.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame))

let path = CGPathCreateMutable()

MoveToPoint(path, x: 51 , y:22 , node:sprite)
AddLineToPoint(path, x: 38 , y:45 , node:sprite)
AddLineToPoint(path, x: 32 , y:44 , node:sprite)
AddLineToPoint(path, x: 32 , y:0 , node:sprite)
AddLineToPoint(path, x: 39 , y:0 , node:sprite)

CGPathCloseSubpath(path)

let path2 = CGPathCreateMutable()

MoveToPoint(path2, x: 0 , y:22 , node:sprite)
AddLineToPoint(path2, x: 13 , y:0 , node:sprite)
AddLineToPoint(path2, x: 19 , y:0 , node:sprite)
AddLineToPoint(path2, x: 19 , y:45 , node:sprite)
AddLineToPoint(path2, x: 13 , y:45 , node:sprite)

CGPathCloseSubpath(path2)

let b1 = SKPhysicsBody(polygonFromPath: path)

let b2 = SKPhysicsBody(polygonFromPath: path2)

sprite.physicsBody = SKPhysicsBody(bodies: [b1, b2])