timer

src/main/kotlin/ru/dbotthepony/kstarbound/Main.kt

@@ -137,6 +137,14 @@ fun main() {
 			}
 		}
 
+		for (i in 0 .. 10) {
+			client.world!!.timer(i * 1.0, 1) {
+				val projEnt = Projectile(client.world!!, Starbound.projectilesAccess["pill"]!!)
+				projEnt.position = Vector2d(i * 2.0 - 15.0, 13.0)
+				projEnt.spawn()
+			}
+		}
+
 		run {
 			val stripes = 0
 

src/main/kotlin/ru/dbotthepony/kstarbound/world/World.kt

@@ -105,6 +105,40 @@ data class WorldSweepResult(
 
 private const val EPSILON = 0.00001
 
+class Timer(val period: Double, val executionTimes: Int, val func: (Timer) -> Unit) {
+	private var counter = 0.0
+	var cycles = 0
+		private set
+	var destroyed: Boolean = false
+		private set
+
+	fun think(delta: Double) {
+		if (destroyed) {
+			throw IllegalStateException("This timer is destroyed")
+		}
+
+		counter += delta
+
+		if (counter >= period) {
+			counter -= period
+			func.invoke(this)
+			cycles++
+		}
+
+		if (!destroyed && executionTimes > 0 && cycles >= executionTimes) {
+			destroy()
+		}
+	}
+
+	fun destroy() {
+		if (destroyed) {
+			throw IllegalStateException("Already destroyed")
+		}
+
+		destroyed = true
+	}
+}
+
 abstract class World<This : World<This, ChunkType>, ChunkType : Chunk<This, ChunkType>>(val seed: Long = 0L) {
 	protected val chunkMap = HashMap<ChunkPos, IMutableWorldChunkTuple<This, ChunkType>>()
 
@@ -117,6 +151,14 @@ abstract class World<This : World<This, ChunkType>, ChunkType : Chunk<This, Chun
 
 	val physics = B2World(Vector2d(0.0, -EARTH_FREEFALL_ACCELERATION))
 
+	private var timers = ArrayList<Timer>()
+
+	fun timer(period: Double, executionTimes: Int, func: (Timer) -> Unit): Timer {
+		val timer = Timer(period, executionTimes, func)
+		timers.add(timer)
+		return timer
+	}
+
 	init {
 		physics.contactFilter = object : IContactFilter {
 			override fun shouldCollide(fixtureA: B2Fixture, fixtureB: B2Fixture): Boolean {
@@ -220,6 +262,28 @@ abstract class World<This : World<This, ChunkType>, ChunkType : Chunk<This, Chun
 			physics.step(delta, 6, 4)
 
 			timer += delta
+
+			if (timers.isNotEmpty()) {
+				val current = timers
+				timers = ArrayList()
+
+				val iterator = current.iterator()
+
+				for (timer in iterator) {
+					timer.think(delta)
+
+					if (timer.destroyed) {
+						iterator.remove()
+					}
+				}
+
+				if (timers.isNotEmpty()) {
+					current.addAll(timers)
+				}
+
+				timers = current
+			}
+
 			thinkInner(delta)
 		} catch(err: Throwable) {
 			throw RuntimeException("Ticking world $this", err)