Is there a way to visually see sprite kit's SKPhysicsbody borderline?

问题

I am using bodyWithPolygonFromPath to define the volume of the physicsbody, and used

http://dazchong.com/spritekit/

to get the paths required. But the path does not seem correct and I wish to see the borderline of the physicsbody path to see if the shape is correct.

Is there any way to see the physicsbody's volume outline?

I tried the following code, but it doesn't work.

ship = [SKSpriteNode spriteNodeWithImageNamed:@"Spaceship"];

CGFloat offsetX = ship.frame.size.width * ship.anchorPoint.x;
CGFloat offsetY = ship.frame.size.height * ship.anchorPoint.y;

CGMutablePathRef path = CGPathCreateMutable();

CGPathMoveToPoint(path, NULL, 50 - offsetX, 110 - offsetY);
CGPathAddLineToPoint(path, NULL, 18 - offsetX, 16 - offsetY);
CGPathAddLineToPoint(path, NULL, 140 - offsetX, 15 - offsetY);

CGPathCloseSubpath(path);

SKShapeNode *yourline = [SKShapeNode node];
yourline.name = @"yourline";
yourline.path = path;
[yourline setStrokeColor:[UIColor redColor]];
 [self addChild:yourline];


ship.physicsBody = [SKPhysicsBody bodyWithPolygonFromPath:path];
//[ship setScale:0.5];
ship.zRotation = - M_PI / 2;

回答1:

For Objective-C & iOS < 7.1

In your ViewController.m find this code

SKView *skView = (SKView *)self.view;
skView.showsFPS = YES;
skView.showsNodeCount = YES;

After the last line add

skView.showsPhysics = YES;

Build and Run and you should see all the physics Body borderline

i noticed that you add the shapeNode to self instead of the spriteNode so try the following

SKSpriteNode *ship = [SKSpriteNode spriteNodeWithImageNamed:@"Spaceship"];
CGFloat offsetX = ship.frame.size.width * ship.anchorPoint.x;
CGFloat offsetY = ship.frame.size.height * ship.anchorPoint.y;

CGMutablePathRef path = CGPathCreateMutable();
CGPathMoveToPoint(path, NULL, 50 - offsetX, 110 - offsetY);
CGPathAddLineToPoint(path, NULL, 18 - offsetX, 16 - offsetY);
CGPathAddLineToPoint(path, NULL, 140 - offsetX, 15 - offsetY);
CGPathCloseSubpath(path);

ship.physicsBody = [SKPhysicsBody bodyWithPolygonFromPath:path];

[self addChild:ship];

SKShapeNode *shape = [SKShapeNode node];
shape.path = path;
shape.strokeColor = [SKColor colorWithRed:1.0 green:0 blue:0 alpha:0.5];
shape.lineWidth = 1.0;
[ship addChild:shape];

For Swift & iOS >= 8.0

let skView = self.view as! SKView
skView.showsFPS = true
skView.showsNodeCount = true
skView.showsPhysics = true

And if you want a custom borderline

let ship = SKSpriteNode(imageNamed: "Spaceship")
let offsetX = ship.frame.size.width * ship.anchorPoint.x
let offsetY = ship.frame.size.height * ship.anchorPoint.y

let path = CGPathCreateMutable()
CGPathMoveToPoint(path, nil, 50 - offsetX, 110 - offsetY)
CGPathAddLineToPoint(path, nil, 18 - offsetX, 16 - offsetY)
CGPathAddLineToPoint(path, nil, 140 - offsetX, 15 - offsetY)
CGPathCloseSubpath(path)

ship.physicsBody = SKPhysicsBody(polygonFromPath: path)
addChild(ship)

let shape = SKShapeNode()
shape.path = path
shape.strokeColor = SKColor(red: 1.0, green: 0, blue: 0, alpha: 0.5)
shape.lineWidth = 1.0
addChild(shape)

Already tested :]

Good Luck!!

回答2:

For testing purposes, I would setup the ship as an SKShapeNode, comment out yourline SKShapeNode for now and set the ship.path to the same path you are using for your SKPhysicsBody.

Or you could use this:

https://github.com/ymc-thzi/physicsDebugger

回答3:

In the new 7.1 beta there is functionality to allow this as stated above.

回答4:

I know this is a bit late, but I thought you might be interested in my new tool which automatically creates a path around the sprite image (so you don't have to manually click on the points yourself), and then you can adjust various settings to better suit your requirements. The tool also outputs both Objective C and Swift program code for adding the path to a sprite physics body. Hope it's helpful to some people. Thanks:

http://www.radicalphase.com/pathgen/

回答5:

Your shape node code is correct. It looks like yourline may be added to the scene before the actual ship, so the ship sprite will be drawn on top of it, making it obscured. Make sure you set yourline.zPosition to the topmost value, or ensure [self addChild:yourline] is executed after [self addChild:ship].

回答6:

This will add a red line shape on top of your node. Use same path as you defined for the physics body of your node.

+(void)debugPath:(CGPathRef)path onNode:(SKNode*)node {
    SKShapeNode *yourline = [SKShapeNode node];
    yourline.name = @"yourline";
    yourline.path = path;
    [yourline setStrokeColor:[UIColor redColor]];
    [node addChild:yourline];
}

I.e. usage:

[[self class] debugPath:ship.physicsBody.path onNode:ship];

回答7:

Swift

In GameViewController.swift

add this line

override func viewDidLoad() {
    ...        
    if let view = self.view as! SKView? {
        ...
    }
    view.showsPhysics = true // <--- add this line
}

来源：https://stackoverflow.com/questions/21213755/is-there-a-way-to-visually-see-sprite-kits-skphysicsbody-borderline