如何在SKSpriteNodes中切割随机孔 [英] How to cut random holes in SKSpriteNodes
问题描述
除了以下问题外，用SpriteKit在矩形中绘制孔?在以下情况中未得到令人满意的回答:两者之间最重要的区别在于，这个问题本身就没有解决方法，并且特别要求反转SKCropNodes的功能.
由于孔的随机性，孔的数量以及要应用孔的对象的变化，无法通过hacky方式来解决此问题的主要问题
以瑞士奶酪为例:
想象一堆随机大小的矩形SKSpriteNode，其中填充了各种深浅的像奶酪一样的颜色.
如何通过在每片奶酪中切出随机的圆圈来使瑞士奶酪出类拔萃?
如果SKCropNodes是圆形，则它们仅留下圆形的奶酪片，而不是在奶酪片上切孔.有没有一种方法可以反转SKCropNodes的行为，从而代替它们切孔?
以我的全部诚实，我并不确定要深入了解您要实现的目标，但是我可以尝试回答以下问题:
..从每片奶酪中切出随机的圆圈吗?
在这个项目中，我尝试重新构建一个带有随机孔的典型矩形(一块奶酪)，然后提取这些孔并将它们收集到一个数组中.
import SpriteKit
class GameScene: SKScene {
struct Cheese
{
static let color1 = SKColor(red: 255/255, green: 241/255, blue: 173/255, alpha: 1)
static let color2 = SKColor(red: 255/255, green: 212/255, blue: 0/255, alpha: 1)
static let color3 = SKColor(red: 204/255, green: 170/255, blue: 0/255, alpha: 1)
static let color4 = SKColor(red: 140/255, green: 116/255, blue: 0/255, alpha: 1)
}
let cheeseColor = [Cheese.color1,Cheese.color2,Cheese.color3,Cheese.color4]
override func didMove(to view: SKView) {
let totHoles = randomNumber(range:4...8)
let color = randomNumber(range:0...3)
let cheeseCropNode = makeCheese(size: CGSize(width:400,height:200),color: cheeseColor[color], totHoles:totHoles)
cheeseCropNode.position = CGPoint(x:0,y:-50)
addChild(cheeseCropNode)
// Start to collect and show holes
var holes = [SKNode]()
var counter = 1
let _ = cheeseCropNode.enumerateChildNodes(withName: "//hole*", using:{ node, stop in
// node is the hole
let pos = self.convert(node.position, from: cheeseCropNode)
let sprite = SKSpriteNode.init(color: .red, size: node.frame.size)
sprite.position = pos
//Remove these shapes, it's just to debug
let shape = SKShapeNode.init(rect: sprite.frame)
shape.strokeColor = .red
self.addChild(shape)
// -- end to remove
let holeTxt = SKView().texture(from: cheeseCropNode, crop: sprite.frame)
let hole = SKSpriteNode.init(texture: holeTxt)
hole.position = CGPoint(x:-(self.frame.maxX)+(100*CGFloat(counter)),y:150)
hole.name = node.name
self.addChild(hole)
holes.append(hole)
counter += 1
})
}
func randomNumber(range: ClosedRange<Int> = 1...6) -> Int {
let min = range.lowerBound
let max = range.upperBound
return Int(arc4random_uniform(UInt32(1 + max - min))) + min
}
func randomCGFloat(min: CGFloat, max: CGFloat) -> CGFloat {
return (CGFloat(arc4random()) / CGFloat(UINT32_MAX)) * (max - min) + min
}
func makeCheese(size:CGSize , color:SKColor, totHoles:Int)->SKCropNode {
let cropNode = SKCropNode()
let cheese = SKSpriteNode.init(color: color, size: size)
for i in 0..<totHoles {
let radius = randomCGFloat(min:20.0, max:50.0)
let circle = SKShapeNode(circleOfRadius: radius)
circle.position = CGPoint(x:randomCGFloat(min:-size.width/2, max:size.width/2),y:randomCGFloat(min:-size.height/2, max:size.height/2))
circle.fillColor = color
circle.blendMode = .subtract
circle.name = "hole\(i)"
cheese.addChild(circle)
}
cropNode.addChild(cheese)
cropNode.maskNode = cheese
return cropNode
}
}
结果:
P.S.不要注意红色矩形，它只是向您显示孔:
如果要精确地反转孔(负图)，可以将SKCropNode与hole.blendMode一起使用，例如:
替换这部分代码:
// -- end to remove
let holeTxt = SKView().texture(from: cheeseCropNode, crop: sprite.frame)
let hole = SKSpriteNode.init(texture: holeTxt)
hole.position = CGPoint(x:-(self.frame.maxX)+(100*CGFloat(counter)),y:150)
hole.name = node.name
self.addChild(hole)
holes.append(hole)
counter += 1
与此部分:
// -- end to remove
let holeTxt = SKView().texture(from: cheeseCropNode, crop: sprite.frame)
let hole = SKSpriteNode.init(texture: holeTxt)
hole.position = CGPoint(x:-(self.frame.maxX)+(100*CGFloat(counter)),y:150)
hole.name = node.name
let negativeCropHole = SKCropNode()
let shadow = SKShapeNode.init(rect: hole.frame)
shadow.fillColor = (node as! SKShapeNode).fillColor
shadow.strokeColor = SKColor.clear
hole.blendMode = .subtract
negativeCropHole.addChild(shadow)
negativeCropHole.maskNode = shadow
negativeCropHole.addChild(hole)
negativeCropHole.name = hole.name
self.addChild(negativeCropHole)
holes.append(negativeCropHole)
counter += 1
结果(另一个示例):
希望这些示例可以帮助您实现目标，我使用矩形制作了蒙版，但是您可以根据需要创建CGPath.
Aside from the fact that the question asked here : Draw a hole in a rectangle with SpriteKit? has not satisfactorily been answered in its own right, the most significant difference between the two is that this question requires an absence of workarounds and specifically asks about reversing the functionality of SKCropNodes.
The primary concerns in this question cannot be addressed by the type of hacky ways the above question could be answered due to the randomness of the holes, the number of holes, and the variation in objects to which the holes are to be applied.
Hence the Swiss Cheese example:
Imagine a bunch of randomly sized rectangular SKSpriteNodes filled with various shades of cheese-like colours.
How to make Swiss Cheese out of each by cutting random circles out of each slice of cheese?
If SKCropNodes are the circles, they only leave circular pieces of cheese rather than cutting holes out of the pieces of cheese. Is there a way to invert the behaviour of SKCropNodes so they cut holes instead?
In my total honesty, I'm not really sure to understand deeply what do you want to achieve, but I can try to answer to this question:
..cutting random circles out of each slice of cheese?
In this project I've try to re-build a typical rectangle (the piece of cheese) with random holes, then I've extract these holes and collect them to an array.
import SpriteKit
class GameScene: SKScene {
struct Cheese
{
static let color1 = SKColor(red: 255/255, green: 241/255, blue: 173/255, alpha: 1)
static let color2 = SKColor(red: 255/255, green: 212/255, blue: 0/255, alpha: 1)
static let color3 = SKColor(red: 204/255, green: 170/255, blue: 0/255, alpha: 1)
static let color4 = SKColor(red: 140/255, green: 116/255, blue: 0/255, alpha: 1)
}
let cheeseColor = [Cheese.color1,Cheese.color2,Cheese.color3,Cheese.color4]
override func didMove(to view: SKView) {
let totHoles = randomNumber(range:4...8)
let color = randomNumber(range:0...3)
let cheeseCropNode = makeCheese(size: CGSize(width:400,height:200),color: cheeseColor[color], totHoles:totHoles)
cheeseCropNode.position = CGPoint(x:0,y:-50)
addChild(cheeseCropNode)
// Start to collect and show holes
var holes = [SKNode]()
var counter = 1
let _ = cheeseCropNode.enumerateChildNodes(withName: "//hole*", using:{ node, stop in
// node is the hole
let pos = self.convert(node.position, from: cheeseCropNode)
let sprite = SKSpriteNode.init(color: .red, size: node.frame.size)
sprite.position = pos
//Remove these shapes, it's just to debug
let shape = SKShapeNode.init(rect: sprite.frame)
shape.strokeColor = .red
self.addChild(shape)
// -- end to remove
let holeTxt = SKView().texture(from: cheeseCropNode, crop: sprite.frame)
let hole = SKSpriteNode.init(texture: holeTxt)
hole.position = CGPoint(x:-(self.frame.maxX)+(100*CGFloat(counter)),y:150)
hole.name = node.name
self.addChild(hole)
holes.append(hole)
counter += 1
})
}
func randomNumber(range: ClosedRange<Int> = 1...6) -> Int {
let min = range.lowerBound
let max = range.upperBound
return Int(arc4random_uniform(UInt32(1 + max - min))) + min
}
func randomCGFloat(min: CGFloat, max: CGFloat) -> CGFloat {
return (CGFloat(arc4random()) / CGFloat(UINT32_MAX)) * (max - min) + min
}
func makeCheese(size:CGSize , color:SKColor, totHoles:Int)->SKCropNode {
let cropNode = SKCropNode()
let cheese = SKSpriteNode.init(color: color, size: size)
for i in 0..<totHoles {
let radius = randomCGFloat(min:20.0, max:50.0)
let circle = SKShapeNode(circleOfRadius: radius)
circle.position = CGPoint(x:randomCGFloat(min:-size.width/2, max:size.width/2),y:randomCGFloat(min:-size.height/2, max:size.height/2))
circle.fillColor = color
circle.blendMode = .subtract
circle.name = "hole\(i)"
cheese.addChild(circle)
}
cropNode.addChild(cheese)
cropNode.maskNode = cheese
return cropNode
}
}
Result:
P.S. Don't pay attention to red rectangles, it's just to show you the holes:
If you want the exactly reversed hole, (the negative image), you could use SKCropNode with the hole.blendMode, for example:
Substitute this part of the code:
// -- end to remove
let holeTxt = SKView().texture(from: cheeseCropNode, crop: sprite.frame)
let hole = SKSpriteNode.init(texture: holeTxt)
hole.position = CGPoint(x:-(self.frame.maxX)+(100*CGFloat(counter)),y:150)
hole.name = node.name
self.addChild(hole)
holes.append(hole)
counter += 1
with this part:
// -- end to remove
let holeTxt = SKView().texture(from: cheeseCropNode, crop: sprite.frame)
let hole = SKSpriteNode.init(texture: holeTxt)
hole.position = CGPoint(x:-(self.frame.maxX)+(100*CGFloat(counter)),y:150)
hole.name = node.name
let negativeCropHole = SKCropNode()
let shadow = SKShapeNode.init(rect: hole.frame)
shadow.fillColor = (node as! SKShapeNode).fillColor
shadow.strokeColor = SKColor.clear
hole.blendMode = .subtract
negativeCropHole.addChild(shadow)
negativeCropHole.maskNode = shadow
negativeCropHole.addChild(hole)
negativeCropHole.name = hole.name
self.addChild(negativeCropHole)
holes.append(negativeCropHole)
counter += 1
Result (another example):
Hope these example and this code help you to obtain your objectives, I've used rectangles to make masks but your could create CGPaths if you need.
这篇关于如何在SKSpriteNodes中切割随机孔的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
