infinity

Sources/Voxelotl/Chunk.swift

@@ -1,3 +1,5 @@
+import simd
+
 public struct Chunk {
   public static let shift = 4  // 16
   public static let size: Int = 1 << shift
@@ -11,6 +13,10 @@ public struct Chunk {
   public let origin: SIMD3<Int>
   private var blocks: [Block]
 
+  static func getID(position: SIMD3<Float>) -> SIMD3<Int> {
+    SIMD3(floor(position)) &>> Chunk.shift
+  }
+
   init(position: SIMD3<Int>, blocks: [Block]) {
     assert(blocks.count == Self.blockCount)
     self.origin = position

Sources/Voxelotl/Game.swift

@@ -78,6 +78,13 @@ class Game: GameDelegate {
     }
 
     self.player.update(deltaTime: deltaTime, world: world, camera: &camera)
+    let centerChunkID = Chunk.getID(position: self.player.position)
+    chunkGenerateNeighbors.forEach { offset in
+          let chunkID = centerChunkID &+ offset
+          if self.world.getChunk(id: chunkID) == nil {
+            self.world.generate(chunkID: chunkID)
+          }
+    }
   }
 
   func draw(_ renderer: Renderer, _ time: GameTime) {
@@ -112,4 +119,34 @@ class Game: GameDelegate {
   func resize(_ size: Size<Int>) {
     self.camera.size = size
   }
+  
+  private let chunkGenerateNeighbors: [SIMD3<Int>] = [
+    SIMD3<Int>(-1, -1, -1),
+    SIMD3<Int>(0, -1, -1),
+    SIMD3<Int>(1, -1, -1),
+    SIMD3<Int>(-1, 0, -1),
+    SIMD3<Int>(0, 0, -1),
+    SIMD3<Int>(1, 0, -1),
+    SIMD3<Int>(-1, 1, -1),
+    SIMD3<Int>(0, 1, -1),
+    SIMD3<Int>(1, 1, -1),
+    SIMD3<Int>(-1, -1, 0),
+    SIMD3<Int>(0, -1, 0),
+    SIMD3<Int>(1, -1, 0),
+    SIMD3<Int>(-1, 0, 0),
+    SIMD3<Int>(0, 0, 0),
+    SIMD3<Int>(1, 0, 0),
+    SIMD3<Int>(-1, 1, 0),
+    SIMD3<Int>(0, 1, 0),
+    SIMD3<Int>(1, 1, 0),
+    SIMD3<Int>(-1, -1, 1),
+    SIMD3<Int>(0, -1, 1),
+    SIMD3<Int>(1, -1, 1),
+    SIMD3<Int>(-1, 0, 1),
+    SIMD3<Int>(0, 0, 1),
+    SIMD3<Int>(1, 0, 1),
+    SIMD3<Int>(-1, 1, 1),
+    SIMD3<Int>(0, 1, 1),
+    SIMD3<Int>(1, 1, 1),
+  ]
 }

Sources/Voxelotl/World.swift

@@ -4,6 +4,8 @@ public class World {
   private var _chunks: Dictionary<SIMD3<Int>, Chunk>
   private var _generator: WorldGenerator
 
+  let _chunkLock: NSLock = .init()
+  
   public init() {
     self._chunks = [:]
     self._generator = WorldGenerator()
@@ -19,6 +21,13 @@ public class World {
     self._chunks[position &>> Chunk.shift]?.setBlock(at: position, type: type)
   }
   
+  func getChunk(id chunkID: SIMD3<Int>) -> Chunk? {
+    self._chunkLock.lock()
+    let chunk = self._chunks[chunkID]
+    self._chunkLock.unlock()
+    return chunk
+  }
+
   func generate(width: Int, height: Int, depth: Int, seed: UInt64) {
     self._generator.reset(seed: seed)
     let orig = SIMD3(width, height, depth) / 2
@@ -26,18 +35,27 @@ public class World {
       for y in 0..<height {
         for x in 0..<width {
           let chunkID = SIMD3(x, y, z) &- orig
-          self._chunks[chunkID] = self._generator.makeChunk(id: chunkID)
+          self.generate(chunkID: chunkID)
         }
       }
     }
   }
 
   func generate(chunkID: SIMD3<Int>) {
-    self._chunks[chunkID] = self._generator.makeChunk(id: chunkID)
+    if self._generator.isCurrentlyGenerating(id: chunkID) { return }
+    self._generator.makeChunk(id: chunkID) { chunk in
+      self._chunkLock.lock()
+      self._chunks[chunkID] = chunk
+      self._chunkLock.unlock()
+    }
   }
 
   var instances: [Instance] {
-    self._chunks.values.flatMap { chunk in
+    self._chunkLock.lock()
+    defer {
+      self._chunkLock.unlock()
+    }
+    return self._chunks.values.flatMap { chunk in
       chunk.compactMap { block, position in
         if case let .solid(color) = block.type {
           Instance(

Sources/Voxelotl/WorldGenerator.swift

@@ -1,7 +1,11 @@
-struct WorldGenerator {
-  var noise: ImprovedPerlin<Float>!, noise2: SimplexNoise<Float>!
+import Foundation
 
-  public mutating func reset(seed: UInt64) {
+class WorldGenerator: NSObject {
+  var noise: ImprovedPerlin<Float>!, noise2: SimplexNoise<Float>!
+  var generating: Set<SIMD3<Int>> = .init()
+  let generatingLock: NSLock = .init()
+  
+  public func reset(seed: UInt64) {
     var random: any RandomProvider
     let initialState = SplitMix64.createState(seed: seed)
 #if true
@@ -14,7 +18,29 @@ struct WorldGenerator {
     self.noise2 = SimplexNoise<Float>(random: &random)
   }
 
-  public func makeChunk(id chunkID: SIMD3<Int>) -> Chunk {
+  public func isCurrentlyGenerating(id chunkID: SIMD3<Int>) -> Bool {
+    self.generatingLock.lock()
+    defer {
+      self.generatingLock.unlock()
+    }
+    return self.generating.contains(chunkID)
+  }
+  
+  public func makeChunk(id chunkID: SIMD3<Int>, completion: @escaping (Chunk) -> Void) {
+    self.generatingLock.lock()
+    print(self.generating)
+    if !self.generating.insert(chunkID).inserted {
+        self.generatingLock.unlock()
+        return
+    }
+    self.generatingLock.unlock()
+    DispatchQueue.global(qos: .userInteractive).async {
+      defer {
+        self.generatingLock.lock()
+        self.generating.remove(chunkID)
+        self.generatingLock.unlock()
+      }
+      
       let chunkOrigin = chunkID &<< Chunk.shift
       var chunk = Chunk(position: chunkOrigin)
       chunk.fill(allBy: { position in
@@ -33,7 +59,8 @@ struct WorldGenerator {
           .air
         }
       })
-    return chunk
+      completion(chunk)
+    }
   }
 }