I'm trying to make a matching game, where these circles appear randomly in a rectangular area, without overlapping. Here's the spawning function:
func SpawnRed(){
var Red = SKSpriteNode(imageNamed: "Matched_Red")
Red.size = CGSize(width: 50, height: 50)
Red.zPosition = 1
let MinValueX = self.size.width / 3 + 50
let MaxValueX = self.size.width / 1.5 - 50
let MinValueY = self.size.height / 1.5 + 25
let MaxValueY = self.size.height / 6
let SpawnPointX = UInt32(MaxValueX - MinValueX)
let SpawnPointY = UInt32(MaxValueY - MinValueY)
Red.position = CGPointMake(CGFloat(arc4random_uniform(SpawnPointX)) + MinValueY,CGFloat(arc4random_uniform(SpawnPointY)))
self.addChild(Red)
}
But for some reason, I keep getting
"Thread 1: EXC_BAD_INSTRUCTION(code=EXC_1386_INVOP,subcode=0x0)" error.
Can you find the solution? Also, it'll be so helpful if you tell me how to spawn nodes without overlapping.
Related
I have a function that spawns little balls, randomly positioned, on the screen. The problem I face is that I want to distribute the balls randomly, but when I do so, some balls spawn on top of each other. I want to exclude all the positions that are already taken (and maybe a buffer of a few pixels around the balls), but I don't know how to do so. I worked around this by giving the balls a Physicsbody, so they move off from one another if they happen to spawn on top of each other. But I want them to not spawn on top of each other in the first place. My code for now is the following:
spawnedBalls = [Ball]()
level = Int()
func setupLevel() {
let numberOfBallsToGenerate = level * 2
let boundary: CGFloat = 26
let rightBoundary = scene!.size.width - boundary
let topBoundary = scene!.size.height - boundary
while spawnedBalls.count < numberOfBallsToGenerate {
let randomPosition = CGPoint(x: CGFloat.random(in: boundary...rightBoundary), y: CGFloat.random(in: boundary...topBoundary))
let ball = Ball()
ball.position = randomPosition
ball.size = CGSize(width: 32, height: 32)
ball.physicsBody = SKPhysicsBody(circleOfRadius: ball.size.width)
ball.physicsBody?.affectedByGravity = false
ball.physicsBody?.allowsRotation = false
ball.physicsBody?.categoryBitMask = 1
ball.physicsBody?.collisionBitMask = 1
spawnedBalls.append(ball)
self.addChild(ball)
}
}
I don't know if this problem should be solved by having an array that stores all taken positions, or if I should use some kind of FiledNode, where occupied space can be sort of subtracted, but sadly I am unfamiliar with FieldNodes, so I don't know if that's the right way to face the problem.
Step 1) Replace
let randomPosition = ....
with
let randomPosition = randomPositionInOpenSpace()
Step 2) Write the randomPositionInOpenSpace function:
Idea is:
a) generate a random position
b) is it in open space? if so return that
c) repeat until OK
Then Step 3) write the 'is it in open space' function
For that you need to know if the proposed coordinate is near any of the other balls. For circles, you can test the distance between their centers is greater than (radiuses + margins). Distance between centers is pythagoras: sqrt of the x delta squared plus the y delta squared.
I am trying to create a line chart which represents a set of values (x and y) in a smooth bezier curve. This works fine, except when the x-values are close to each other and the y-values go from a continuous line to a lower or higher value. The values are not shown in the chart itself, but here is an image illustrating my problem:
As you can see, the line makes a backwards movement before continuing to the next point. I would like this to not happen and smoothen out. To generate the data points, I use this library from Minh Nguyen, which has helped me a lot. The only problem is this issue still. For easiness, here is the code I currently use:
private func controlPointsFrom(points: [CGPoint]) -> [CurvedSegment] {
var result: [CurvedSegment] = []
let delta: CGFloat = 0.3
for i in 1..<points.count {
let A = points[i-1]
let B = points[i]
let controlPoint1 = CGPoint(x: A.x + delta*(B.x-A.x), y: A.y + delta*(B.y - A.y))
let controlPoint2 = CGPoint(x: B.x - delta*(B.x-A.x), y: B.y - delta*(B.y - A.y))
let curvedSegment = CurvedSegment(controlPoint1: controlPoint1, controlPoint2: controlPoint2)
result.append(curvedSegment)
}
for i in 1..<points.count-1 {
let M = result[i-1].controlPoint2
let N = result[i].controlPoint1
let A = points[i]
let MM = CGPoint(x: 2 * A.x - M.x, y: 2 * A.y - M.y)
let NN = CGPoint(x: 2 * A.x - N.x, y: 2 * A.y - N.y)
result[i].controlPoint1 = CGPoint(x: (MM.x + N.x)/2, y: (MM.y + N.y)/2)
result[i-1].controlPoint2 = CGPoint(x: (NN.x + M.x)/2, y: (NN.y + M.y)/2)
}
return result
}
func createCurvedPath(_ dataPoints: [CGPoint]) -> UIBezierPath? {
let path = UIBezierPath()
path.move(to: dataPoints[0])
var curveSegments: [CurvedSegment] = []
let useDataPoints = dataPoints.filter { ($0.y < 1000) }
curveSegments = controlPointsFrom(points: useDataPoints)
for i in 1..<useDataPoints.count {
path.addCurve(to: useDataPoints[i], controlPoint1: curveSegments[i - 1].controlPoint1, controlPoint2: curveSegments[i - 1].controlPoint2)
}
return path
}
For documentation, I would refer to the tutorial/blogpost I linked earlier. I figure the issue should be somewhere in the calculation of controlPoint1 and controlPoint2 in the controlPointsFrom function. When I remove the delta or make it 0, it just become straight lines but then the issue doesn't occur either. So the math should be different I think, to keep track of the previous value and perhaps don't create a control point with a higher or lower y-value when the next point is lower or higher, respectively. But I am unable to figure out how to make it work. Any smart mind who can make this happen?
Would be forever grateful!
try this:
Smooth UIBezierPath
https://medium.com/#ramshandilya/draw-smooth-curves-through-a-set-of-points-in-ios-34f6d73c8f9
This is code that I had to update from and outdated blog post
import SpriteKit
class CreateEnemies {
var enemySprites: [SKSpriteNode] = []
static var lowerRate = 120
static var upperRate = 250
func spawnEnemy(targetSprite: SKNode) -> SKSpriteNode {
// create a new enemy sprite
let newEnemy = SKSpriteNode(imageNamed:"sharkshark")
enemySprites.append(newEnemy)
newEnemy.size = CGSize(width: 35, height: 35)
let randomXStart = CGFloat(arc4random_uniform(UInt32(2000 - (-2000)))) + CGFloat(-2000)
let randomYStart = CGFloat(arc4random_uniform(UInt32(2000 - (-2000)))) + CGFloat(-2000)
let xInt = Int(randomXStart)
let yInt = Int(randomYStart)
newEnemy.position = CGPoint(x: xInt, y: yInt)
// Define Constraints for orientation/targeting behavior
let i = enemySprites.count-1
let rangeForOrientation = SKRange(constantValue:CGFloat(M_2_PI*7))
let orientConstraint = SKConstraint.orient(to: targetSprite, offset: rangeForOrientation)
let rangeToSprite = SKRange(lowerLimit: CGFloat(CreateEnemies.lowerRate), upperLimit: CGFloat(CreateEnemies.upperRate))
var distanceConstraint: SKConstraint
// First enemy has to follow spriteToFollow, second enemy has to follow first enemy, ...
if enemySprites.count-1 == 0 {
distanceConstraint = SKConstraint.distance(rangeToSprite, to: targetSprite)
} else {
distanceConstraint = SKConstraint.distance(rangeToSprite, to: enemySprites[i-1])
}
newEnemy.constraints = [orientConstraint, distanceConstraint]
return newEnemy
}
}
I was wondering how I would make the enemies get closer to the target gradually the longer they exist.
I tried changing the variables every 5 seconds using a
let wait5 = SKAction.wait(forDuration: 5)
let getCloser = SKAction.repeatForever(SKAction.sequence([wait5, SKAction.run {self.changeRates()}]))
self.run(getCloser)
and attaching it to run a function
func changeRates() {
CreateEnemies.lowerRate -= 25
CreateEnemies.upperRate -= 25
}
A few things here:
1) your random is based on a square not a circle, so you are going to find your enemies spawning more on the corners than in the center of each side of your screen. I would recommend making a random angle between 0 and 2 pi, a random radius of I am guessing between 0 and 2000, and then setting your position using CGPoint(x:cos(angle) * radius, y:sin(angle) * radius)
2) your lowerRate is going to hit negative in 25 seconds, That may become a problem. I would use a percentage instead:
lowerRate = lowerRateStart * percentage
percentage *= 0.90
This will reduce your sprites 10 percent of their current location, so 90 81 73 64 58 52 47 42 38 34 31 28 25 22 20 18 16 14 13 12 11 10 9 8 7 6 5 4..... then be between 4 and 0 for a while. This basically assures that your number approaches zero, but will never become 0.
3) Your random start and your distance constraint are not correlating correctly, and this may cause problems. I would recommend setting the position somewhere inside of your distance constraint radius, so your rates should be:
let radius = CGFloat(arc4random_uniform(UInt32(upperRate - lowerRate)))
newEnemy.position = CGPoint(x:cos(angle) * radius + lowerRate + targetSprite.x, y:sin(angle) * radius + lowerRate + targetSprite.y)
I use the following function to append physicsbodies on tiles from a SKTileMapNode:
static func addPhysicsBody(to tileMap: SKTileMapNode, and tileInfo: String){
let tileSize = tileMap.tileSize
let halfWidth = CGFloat(tileMap.numberOfColumns) / 2 * tileSize.width
let halfHeight = CGFloat(tileMap.numberOfRows) / 2 * tileSize.height
for row in 0..<tileMap.numberOfColumns{
for column in 0..<tileMap.numberOfRows{
let tileDefinition = tileMap.tileDefinition(atColumn: column, row: row)
let isCorrectTile = tileDefinition?.userData?[tileInfo] as? Bool
if isCorrectTile ?? false && tileInfo == "wall"{
let x = CGFloat(column) * tileSize.width - halfWidth
let y = CGFloat(row) * tileSize.height - halfHeight
let tileNode = SKNode()
tileNode.position = CGPoint(x: x, y: y)
tileNode.physicsBody = SKPhysicsBody.init(rectangleOf: tileSize, center: CGPoint(x: tileSize.width / 2, y: tileSize.height / 2))
tileNode.physicsBody!.isDynamic = false
tileNode.physicsBody!.restitution = 0.0
tileNode.physicsBody!.categoryBitMask = Constants.PhysicsCategories.wall
tileNode.physicsBody!.collisionBitMask = Constants.PhysicsCategories.player | Constants.PhysicsCategories.npc | Constants.PhysicsCategories.enemy
nodesForGraph.append(tileNode)
tileMap.addChild(tileNode)
}
}
}
}
However if I use this, I have a physicsbody per tile. I want to connect physicsbodies to bigger ones to get a better performance. I know that this can be with init(bodies: [SKPhysicsBody]). But how can I do that?
How can I find out which body is next to another body to group them?
The physicsbodies in the tileMap aren't all next to each other. Some are big blocks of physicsbodies, some are single physicsbodies with no bodies next to them. So I can't simply put every physicsbody in an array and group them.
Here's an image that shows how it looks like at the moment.
I hope the explanation is clear enough. If not, I will try to explain it better.
Has anyone done this before and can point me in the right direction? I would appreciate any help.
EDIT:
Before I tried this:
static var bodies = [SKPhysicsBody]()
static func addPhysicsBody(to tileMap: SKTileMapNode, and tileInfo: String){
let tileSize = tileMap.tileSize
let halfWidth = CGFloat(tileMap.numberOfColumns) / 2 * tileSize.width
let halfHeight = CGFloat(tileMap.numberOfRows) / 2 * tileSize.height
for column in 0..<tileMap.numberOfColumns{
for row in 0..<tileMap.numberOfRows{
let tileDefinition = tileMap.tileDefinition(atColumn: column, row: row)
let isCorrectTile = tileDefinition?.userData?[tileInfo] as? Bool
if isCorrectTile ?? false && tileInfo == "wall"{
let x = CGFloat(column) * tileSize.width - halfWidth
let y = CGFloat(row) * tileSize.height - halfHeight
let tileNode = SKNode()
tileNode.position = CGPoint(x: x, y: y)
tileNode.physicsBody = SKPhysicsBody.init(rectangleOf: tileSize, center: CGPoint(x: tileSize.width / 2, y: tileSize.height / 2))
tileNode.physicsBody!.isDynamic = false
tileNode.physicsBody!.restitution = 0.0
tileNode.physicsBody!.categoryBitMask = Constants.PhysicsCategories.wall
tileNode.physicsBody!.collisionBitMask = Constants.PhysicsCategories.player | Constants.PhysicsCategories.npc | Constants.PhysicsCategories.enemy
//nodesForGraph.append(tileNode)
bodies.append(tileNode.physicsBody!)
tileMap.addChild(tileNode)
}
}
}
tileMap.physicsBody = SKPhysicsBody(bodies: bodies)
}
But when I do this, the physicsbodies are totally messed up..
I recommend applying a line sweep algorithm to merge the tiles together.
You can do this in four steps;
Iterate through the position of the tiles in your SKTileMap.
Find the tiles that are adjacent to one another.
For each group of adjacent tiles, collect:
a down-left corner coordinate and
an up-right corner coordinate.
Draw a square, and move on to the next group of tiles until you run out of tile coordinates.
The first step: creating an array containing all of your position nodes.
func tilephysics() {
let tilesize = tileMap.tileSize
let halfwidth = CGFloat(tileMap.numberOfColumns) / 2.0 * tilesize.width
let halfheight = CGFloat(tileMap.numberOfRows) / 2.0 * tilesize.height
for col in 0 ..< tileMap.numberOfColumns {
for row in 0 ..< tileMap.numberOfRows {
if (tileMap.tileDefinition(atColumn: col, row: row)?.userData?.value(forKey: "ground") != nil) {
let tileDef = tileMap.tileDefinition(atColumn: col, row: row)!
let tile = SKSpriteNode()
let x = round(CGFloat(col) * tilesize.width - halfwidth + (tilesize.width / 2))
let y = round(CGFloat(row) * tilesize.height - halfheight + (tilesize.height / 2))
tile.position = CGPoint(x: x, y: y)
tile.size = CGSize(width: tileDef.size.width, height: tileDef.size.height)
tileArray.append(tile)
tilePositionArray.append(tile.position)
}
}
}
algorithm()
}
The second and third step: finding adjacent tiles, collecting the two corner coordinates, and adding them to an array:
var dir = [String]()
var pLoc = [CGPoint]()
var adT = [CGPoint]()
func algorithm(){
let width = tileMap.tileSize.width
let height = tileMap.tileSize.height
let rWidth = 0.5 * width
let rHeight = 0.5 * height
var ti:Int = 0
var ti2:Int = 0
var id:Int = 0
var dl:CGPoint = CGPoint(x: 0, y: 0)
var tLE = [CGPoint]()
var tRE = [CGPoint]()
for t in tilePositionArray {
if (ti-1 < 0) || (tilePositionArray[ti-1].y != tilePositionArray[ti].y - height) {
dl = CGPoint(x: t.x - rWidth, y: t.y - rHeight)
}
if (ti+1 > tilePositionArray.count-1) {
tLE.append(dl)
tRE.append(CGPoint(x: t.x + rWidth, y: t.y + rHeight))
} else if (tilePositionArray[ti+1].y != tilePositionArray[ti].y + height) {
if let _ = tRE.first(where: {
if $0 == CGPoint(x: t.x + rWidth - width, y: t.y + rHeight) {id = tRE.index(of: $0)!}
return $0 == CGPoint(x: t.x + rWidth - width, y: t.y + rHeight)}) {
if tLE[id].y == dl.y {
tRE[id] = CGPoint(x: t.x + rWidth, y: t.y + rHeight)
} else {
tLE.append(dl)
tRE.append(CGPoint(x: t.x + rWidth, y: t.y + rHeight))
}
} else {
tLE.append(dl)
tRE.append(CGPoint(x: t.x + rWidth, y: t.y + rHeight))
}
}
ti+=1
}
The fourth step: drawing a rectangle and moving on to the next shape:
for t in tLE {
let size = CGSize(width: abs(t.x - tRE[ti2].x), height: abs(t.y - tRE[ti2].y))
let loadnode = SKNode()
loadnode.physicsBody = SKPhysicsBody(rectangleOf: size)
loadnode.physicsBody?.isDynamic = false
loadnode.physicsBody?.affectedByGravity = false
loadnode.physicsBody?.restitution = 0
loadnode.physicsBody?.categoryBitMask = 2
loadnode.position.x = t.x + size.width / 2
loadnode.position.y = t.y + size.height / 2
scene.addChild(loadnode)
ti2 += 1
}
}
Apply these steps correctly, and you should see that your tiles are merged together in large squares; like so:
Screenshot without visuals for comparison
Screenshot without visuals showing the physicsbodies
I had a lot of fun solving this problem. If I have helped you, let me know.
I only recently started coding and am looking for new challenges. Please reach out to me if you have challenges or projects I could possibly contribute to.
As Knight0fDragon pointed out, there is no way to do exactly what you have asked. Unfortunately, tile maps in SpriteKit leave much to be desired. But you might try this technique to reduce the number of physics bodies.
Idea #1 - Manually Draw Your Physics Bodies
Create your tile map in the editor. Just paint your tile textures onto the map; don't assign any physics bodies to them. Then keep working in the editor to drag Color Sprites (SKSpriteNodes) over parts of your map that need a physics body. Shape the nodes to make the largest rectangle possible for areas that need physics bodies. This works best for for large, flat surfaces like walls, floors, ceilings, platforms, crates, etc. It's tedious but you end up with far fewer physics bodies in your simulation than if you automatically assign bodies to all tiles like you are doing.
Idea #2 - Use No Physics Bodies
This idea would probably require even more work, but you could potentially avoid using physics bodies altogether. First, create your tile map in the editor. Analyze your map to identify which tiles mark a barrier, beyond which the player should not cross. Assign a user data identifier to that type of tile. You would need different categories of identifiers for different types of barriers, and you may also need to design your artwork to fit this approach.
Once your barrier tiles are sufficiently identified, write code which checks the user data value for the tile currently occupied by the player sprite and restrict the sprite's movement accordingly. For example, if the player enters a title that marks an upper boundary, your movement code would not allow the player sprite to move up. Likewise, if the player enters a tile that marks the leftmost boundary, your movement code will not let the player travel left.
You can check out this related post where I basically suggest the same ideas. Unfortunately, SpriteKit's tile maps have no perfect solution for this problem.
In my current project I create some node that I would like to create physics bodies for.
This creates the nodes:
let seg = SKShapeNode(ellipseOf: CGSize(width: 10 / xScale, height: 10 / yScale))
let offset = (seg.frame.height / 1.5) * CGFloat(i + 1)
seg.position = CGPoint(x: anchorPoint.x, y: ((size.height / 2) / yScale) + (10 / yScale) - offset)
segments.append(seg)
addChild(seg)
And this is how I currently try to create the bodies:
seg.physicsBody = SKPhysicsBody(circleOfRadius: 10 / xScale / yScale / 2)
I dont know how I would go about creating the correct one. It should function like a normal physics body(edge based bodies don't collide with stuff).
Currently when the circles roll down it looks like this although they are initially circles:
Also they look very pixelated. Do you have any idea why?
Thanks for your help!