added ticking logic to particles

src/main/kotlin/com/bytedice/bde_particles/Bde_particles.kt

@@ -11,17 +11,15 @@ import net.fabricmc.fabric.api.event.lifecycle.v1.ServerTickEvents
 import net.fabricmc.fabric.api.event.player.UseItemCallback
 import net.minecraft.entity.player.PlayerEntity
 import net.minecraft.item.ItemStack
-import net.minecraft.server.MinecraftServer
 import net.minecraft.server.network.ServerPlayerEntity
 import net.minecraft.server.world.ServerWorld
-import net.minecraft.text.Text
 import net.minecraft.util.ActionResult
 import net.minecraft.util.Hand
 import net.minecraft.util.TypedActionResult
 import net.minecraft.world.World
 
 
-// const val ALL_PARTICLE_EMITTERS: Array<> // ParticleEmitter
+var ALL_PARTICLE_EMITTERS: Array<ParticleEmitter> = emptyArray()
 
 data class Config(
   val cooldown: Int = 1
@@ -56,12 +54,17 @@ class Bde_particles : ModInitializer {
 
 
 fun init() {
-  addToParticleRegister("DEBUG", ParticleEmitterParams())
+  addToParticleRegister("DEBUG", ParticleEmitterParams(loopDur = 20))
 }
 
 
 fun tick() {
-
+  for (emitter in ALL_PARTICLE_EMITTERS) {
+    if (emitter.isDead) {
+      ALL_PARTICLE_EMITTERS = ALL_PARTICLE_EMITTERS.toMutableList().apply { remove(emitter) }.toTypedArray()
+    }
+    else { emitter.tick() }
+  }
 }
 
 
@@ -80,7 +83,7 @@ fun onRightClick(player: PlayerEntity, world: ServerWorld, hand: Hand) : TypedAc
   }
 
   val emitter = ParticleEmitter(hitResult.pos, world, emitterParams)
-  emitter.tick()
+  ALL_PARTICLE_EMITTERS += emitter
 
   return TypedActionResult(ActionResult.PASS, handItem)
 }

src/main/kotlin/com/bytedice/bde_particles/DisplayEntity.kt

@@ -5,15 +5,17 @@ import net.minecraft.entity.decoration.DisplayEntity.BlockDisplayEntity
 import net.minecraft.nbt.NbtCompound
 import net.minecraft.nbt.NbtFloat
 import net.minecraft.nbt.NbtList
+import net.minecraft.nbt.NbtString
 import net.minecraft.server.world.ServerWorld
 
 class DisplayEntity(val properties: DisplayEntityProperties?) {
   private var hasSpawned = false
+  private var entity: BlockDisplayEntity? = null
 
   fun spawn(world: ServerWorld) : BlockDisplayEntity? {
-    if (this.hasSpawned || properties == null) { return null }
+    if (hasSpawned || properties == null) { return null }
 
-    val e = updateProperties(world, this.properties)
+    val e = updateProperties(world, properties)
     world.spawnEntity(e)
 
     this.hasSpawned = true
@@ -23,8 +25,18 @@ class DisplayEntity(val properties: DisplayEntityProperties?) {
   fun updateProperties(world: ServerWorld, properties: DisplayEntityProperties) : BlockDisplayEntity {
     val e = BlockDisplayEntity(EntityType.BLOCK_DISPLAY, world)
 
+    // TODO: add tag nbt and kill all particles when server starts
     val nbt = NbtCompound().apply {
+      val tagList = NbtList()
+
+      properties.tags.forEach { tag ->
+        tagList.add(NbtString.of(tag))
+      }
+
+      put("Tags", tagList)
+
       put("block_state", NbtCompound().apply { putString("Name", properties.blockType) })
+
       put("transformation", NbtCompound().apply {
         val offsetList = NbtList().apply {
           add(NbtFloat.of(properties.translation.x))
@@ -60,6 +72,11 @@ class DisplayEntity(val properties: DisplayEntityProperties?) {
 
     e.refreshPositionAndAngles(properties.pos.x, properties.pos.y, properties.pos.z, properties.rot.x, properties.rot.y)
 
+    entity = e
     return e
   }
+
+  fun kill() {
+    entity?.kill()
+  }
 }

src/main/kotlin/com/bytedice/bde_particles/DisplayEntityProperties.kt

@@ -10,6 +10,7 @@ data class DisplayEntityProperties (
   val rot: Vector2f = Vector2f(0.0f, 0.0f),
 
   val blockType: String   = "minecraft:purple_concrete",
+  val tags: Array<String> = emptyArray(),
 
   val translation:   Vector3f = Vector3f(-0.5f, -0.5f, -0.5f),
   val leftRotation:  Vector4f = Vector4f(0.0f, 0.0f, 0.0f, 1.0f),

src/main/kotlin/com/bytedice/bde_particles/math/main.kt

@@ -67,24 +67,20 @@ fun quatToEuler(quat: Vector4f): Vector3f {
   val z = quat.z
   val w = quat.w
 
-  // Roll (X-axis rotation)
+  val sinRCosP = 2 * (w * x + y * z)
-  val sinr_cosp = 2 * (w * x + y * z)
+  val cosRCosP = 1 - 2 * (x * x + y * y)
-  val cosr_cosp = 1 - 2 * (x * x + y * y)
+  val roll = atan2(sinRCosP, cosRCosP)
-  val roll = atan2(sinr_cosp, cosr_cosp)
 
-  // Pitch (Y-axis rotation)
+  val sinP = 2 * (w * y - z * x)
-  val sinp = 2 * (w * y - z * x)
+  val pitch = if (abs(sinP) >= 1) {
-  val pitch = if (kotlin.math.abs(sinp) >= 1) {
+    sign(sinP) * (Math.PI.toFloat() / 2)
-    // Use 90 degrees if out of range
-    kotlin.math.sign(sinp) * (Math.PI.toFloat() / 2)
   } else {
-    asin(sinp)
+    asin(sinP)
   }
 
-  // Yaw (Z-axis rotation)
+  val sinYCosP = 2 * (w * z + x * y)
-  val siny_cosp = 2 * (w * z + x * y)
+  val cosYCosP = 1 - 2 * (y * y + z * z)
-  val cosy_cosp = 1 - 2 * (y * y + z * z)
+  val yaw = atan2(sinYCosP, cosYCosP)
-  val yaw = atan2(siny_cosp, cosy_cosp)
 
   return Vector3f(roll, pitch, yaw)
 }
@@ -146,3 +142,8 @@ fun transformOffsetByQuat(offset: Vector3f, rotation: Vector4f): Vector3f {
 fun transformOffsetByScale(offset: Vector3f, scale: Vector3f): Vector3f {
   return offset.mul(scale)
 }
+
+
+fun lerp(x: Float, y: Float, t: Float) : Float {
+  return x + (y - x) * t
+}

src/main/kotlin/com/bytedice/bde_particles/particle/ForceFields.kt

@@ -0,0 +1,10 @@
+package com.bytedice.bde_particles.particle
+
+data class ForceField (
+  val x: Float = 0.0f,
+  val y: Float = 0.0f,
+  val z: Float = 0.0f,
+  val minForce: Float = 0.0f,
+  val maxForce: Float = 0.0f,
+  val radius:   Float = -1.0f
+)

src/main/kotlin/com/bytedice/bde_particles/particle/Particle.kt

@@ -6,57 +6,89 @@ import com.bytedice.bde_particles.math.*
 import net.minecraft.server.world.ServerWorld
 import net.minecraft.util.math.Vec3d
 import org.joml.Vector3f
+import kotlin.math.round
 
 
-class Particle(particleParams: ParticleParams) {
+class Particle(private val particleParams: ParticleParams) {
-  val rot = Vector3f(
+  private val rot = Vector3f(
     randomFloatBetween(particleParams.rotRandom.first.x, particleParams.rotRandom.second.x),
     randomFloatBetween(particleParams.rotRandom.first.y, particleParams.rotRandom.second.x),
     randomFloatBetween(particleParams.rotRandom.first.z, particleParams.rotRandom.second.z)
   )
-  val rotVel = Vector3f(
+  private val rotVel = Vector3f(
     randomFloatBetween(particleParams.rotVelRandom.first.x, particleParams.rotVelRandom.second.x),
     randomFloatBetween(particleParams.rotVelRandom.first.y, particleParams.rotVelRandom.second.x),
     randomFloatBetween(particleParams.rotVelRandom.first.z, particleParams.rotVelRandom.second.z)
   )
-  val scale = Vector3f(
+  private val scale = Vector3f(
     randomFloatBetween(particleParams.sizeRandom.first.x, particleParams.sizeRandom.second.x),
     randomFloatBetween(particleParams.sizeRandom.first.y, particleParams.sizeRandom.second.x),
     randomFloatBetween(particleParams.sizeRandom.first.z, particleParams.sizeRandom.second.z)
   )
-  var blockDisplay: DisplayEntity? = null
+  private var blockDisplay: DisplayEntity? = null
-  val params = particleParams
 
-  var isInit = false
+  var isDead = false
+  private var timeAlive = 0
+
+  private var isInit = false
 
   fun init(pos: Vec3d) {
     val offset = Vector3f(-0.5f, -0.5f, -0.5f)
-    val quatRot = eulerToQuat(this.rot)
+    val quatRot = eulerToQuat(rot)
 
-    val scaleOffset = transformOffsetByScale(offset, this.scale)
+    val scaleOffset = transformOffsetByScale(offset, scale)
     val rotOffset = transformOffsetByQuat(scaleOffset, quatRot)
 
     val properties = DisplayEntityProperties(
       pos          = pos,
-      blockType    = this.params.blockCurve[0],
+      blockType    = particleParams.blockCurve[0],
       translation  = rotOffset,
       leftRotation = quatRot,
-      scale        = this.scale
+      scale        = scale,
+      tags         = arrayOf("BPS_Particle")
     )
     
-    this.blockDisplay = DisplayEntity(properties)
+    blockDisplay = DisplayEntity(properties)
 
-    this.isInit = true
+    isInit = true
   }
 
 
   fun spawn(world: ServerWorld) {
     if (isInit) { blockDisplay?.spawn(world) }
-    else { error("Particle is not initialized before being spawned. Please use Particle.init() to initialize it") }
+    else { error("Particle is not initialized before being spawned. Please use Particle.init() to initialize it.") }
   }
 
 
-  fun tick() {
+  fun tick(world: ServerWorld) {
+    if (!isInit) { error("Particle is not initialized before being ticked. Please use Particle.init() to initialize it.") }
 
+    val properties = blockDisplay?.properties ?: return
+
+    val newProperties = calculateNewProperties(properties, particleParams)
+
+    blockDisplay?.updateProperties(world, newProperties)
+
+    if (timeAlive > particleParams.lifeTime) { isDead = true; blockDisplay?.kill() }
+
+    timeAlive += 1
+  }
+
+
+  private fun calculateNewProperties(propetries: DisplayEntityProperties, params: ParticleParams) : DisplayEntityProperties {
+    val newBlockIdx = round(lerp(
+      0.0f,
+      params.blockCurve.lastIndex.toFloat(),
+      (timeAlive.toFloat() / params.lifeTime.toFloat()).coerceIn(0.0f, 1.0f)
+    )).toInt()
+
+    val newBlock = params.blockCurve[newBlockIdx]
+
+
+    val newProperties = DisplayEntityProperties(
+      blockType = newBlock
+    )
+
+    return newProperties
   }
 }

src/main/kotlin/com/bytedice/bde_particles/particle/ParticleEmitter.kt

@@ -4,18 +4,54 @@ import net.minecraft.server.world.ServerWorld
 import net.minecraft.util.math.Vec3d
 
 class ParticleEmitter(emitterPos: Vec3d, emitterWorld: ServerWorld, emitterParams: ParticleEmitterParams) {
-  val world  = emitterWorld
+  private val world  = emitterWorld
-  val pos    = emitterPos
+  private val pos    = emitterPos
-  val params = emitterParams
+  private val params = emitterParams
-  val allParticles: Array<Particle> = emptyArray()
+
-  val timeAlive = 0
+  private var allParticles: Array<Particle> = emptyArray()
+
+  private var timeAlive = 0
+  private var loopCount = 0
+  private var loopDelay = 0
+  private var loopDur   = 0
+  private var loopDelayActive = false
+
+  var isDead = false
 
 
   fun tick() {
+    count()
+
+    if (!loopDelayActive) {
       repeat(this.params.spawnsPerTick) {
         val particle = Particle(ParticleParams())
         particle.init(this.pos)
         particle.spawn(world)
+        allParticles += particle
       }
     }
+
+    for (particle in allParticles) {
+      if (particle.isDead) { allParticles = allParticles.toMutableList().apply { remove(particle) }.toTypedArray() }
+      else { particle.tick(world) }
+    }
+  }
+
+
+  private fun count() {
+    if (loopDur >= params.loopDur) {
+      loopCount += 1
+      loopDur = 0
+      loopDelayActive = true
+      if (!params.loop) { isDead = true }
+    }
+    else if (loopDelay >= params.loopDelay) {
+      loopDelay = 0
+      loopDelayActive = false
+    }
+
+    if (!loopDelayActive) { loopDur += 1 }
+    else { loopDelay += 1 }
+    timeAlive += 1
+  }
 }

src/main/kotlin/com/bytedice/bde_particles/particle/ParticleParams.kt

@@ -5,24 +5,16 @@ import org.joml.Vector3f
 
 data class ParticleParams (
   //val shape: Shape, // add later, start with single point
-  val blockCurve:   Array<String>            = arrayOf("minecraft:purple_concrete"),
+  val blockCurve:   Array<String>            = arrayOf("minecraft:purple_concrete", "minecraft:purple_stained_glass"),
   val rotRandom:    Pair<Vector3f, Vector3f> = Pair(Vector3f(0.0f, 0.0f, 0.0f), Vector3f(360.0f, 360.0f, 360.0f)),
   val rotVelRandom: Pair<Vector3f, Vector3f> = Pair(Vector3f(1.0f, 1.0f, 1.0f), Vector3f(5.0f, 5.0f, 5.0f)),
   val rotVelCurve:  Array<Vector3f>          = arrayOf(Vector3f(1.0f, 1.0f, 1.0f), Vector3f(0.0f, 0.0f, 0.0f)),
   val sizeRandom:   Pair<Vector3f, Vector3f> = Pair(Vector3f(0.5f, 0.5f, 0.5f), Vector3f(1.0f, 1.0f, 1.0f)),
   val sizeCurve:    Array<Vector3f>          = arrayOf(Vector3f(1.0f, 1.0f, 1.0f), Vector3f(0.0f, 0.0f, 0.0f)),
+  val velRandom:    Pair<Vector3f, Vector3f> = Pair(Vector3f(1.0f, 1.0f, 1.0f), Vector3f(5.0f, 5.0f, 5.0f)),
   val forceFields:  ForceField               = ForceField(),
   val gravity:      Vec3d                    = Vec3d(0.0, -9.0, 0.0),
   val drag:         Float                    = 0.2f,
-  val minVel:       Float                    = 0.003f
+  val minVel:       Float                    = 0.003f,
-)
+  val lifeTime:     Int                      = 20
-
-
-data class ForceField (
-  val x: Float = 0.0f,
-  val y: Float = 0.0f,
-  val z: Float = 0.0f,
-  val minForce: Float = 0.0f,
-  val maxForce: Float = 0.0f,
-  val radius:   Float = -1.0f,
 )