demo/sat-demo/src/main/kotlin/ru/mipt/npm/sat/geometry.kt

@@ -17,6 +17,7 @@ internal fun visionOfSatellite(
     ySegmentSize: Number = xSegmentSize,
     fiberDiameter: Number = 1.0,
 ): SolidGroup = SolidGroup {
+    color("darkgreen")
     val transparent by style {
         this[SolidMaterial.MATERIAL_OPACITY_KEY] = 0.3
     }

visionforge-core/src/commonMain/kotlin/space/kscience/visionforge/VisionBase.kt

@@ -23,7 +23,7 @@ internal data class MetaListener(
 
 /**
  * A full base implementation for a [Vision]
- * @param properties Object own properties excluding styles and inheritance
+ * @param parent the parent object for this vision. Could ve set later. Not serialized.
  */
 @Serializable
 @SerialName("vision")

visionforge-core/src/commonMain/kotlin/space/kscience/visionforge/VisionChange.kt

@@ -82,6 +82,7 @@ public inline fun VisionChange(manager: VisionManager, block: VisionChangeBuilde
     VisionChangeBuilder().apply(block).isolate(manager)
 
 
+@OptIn(DFExperimental::class)
 private fun CoroutineScope.collectChange(
     name: Name,
     source: Vision,
@@ -102,11 +103,13 @@ private fun CoroutineScope.collectChange(
 
         //Subscribe for structure change
         if (source is MutableVisionGroup) {
-            source.structureChanges.onEach { (token, _, after) ->
+            source.structureChanges.onEach { changedName ->
+                val after = source[changedName]
+                val fullName = name + changedName
                 if (after != null) {
-                    collectChange(name + token, after, collector)
+                    collectChange(fullName, after, collector)
                 }
-                collector()[name + token] = after
+                collector()[fullName] = after
             }.launchIn(this)
         }
     }

visionforge-core/src/commonMain/kotlin/space/kscience/visionforge/VisionGroup.kt

@@ -1,6 +1,11 @@
 package space.kscience.visionforge
 
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.channels.awaitClose
 import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.callbackFlow
+import kotlinx.coroutines.launch
+import space.kscience.dataforge.misc.DFExperimental
 import space.kscience.dataforge.names.*
 import space.kscience.dataforge.provider.Provider
 
@@ -69,14 +74,29 @@ public interface VisionContainerBuilder<in V : Vision> {
  * Mutable version of [VisionGroup]
  */
 public interface MutableVisionGroup : VisionGroup, VisionContainerBuilder<Vision> {
+    public fun onStructureChanged(owner: Any?, block: VisionGroup.(Name) -> Unit)
+
+    public fun removeStructureListener(owner: Any?)
+}
 
-    public data class StructureChange(val token: NameToken, val before: Vision?, val after: Vision?)
 
 /**
  * Flow structure changes of this group. Unconsumed changes are discarded
  */
-    public val structureChanges: Flow<StructureChange>
+@OptIn(ExperimentalCoroutinesApi::class)
+@DFExperimental
+public val MutableVisionGroup.structureChanges: Flow<Name>
+    get() = callbackFlow {
+        meta.onChange(this) { name ->
+            launch {
+                send(name)
             }
+        }
+        awaitClose {
+            removeStructureListener(this)
+        }
+    }
+
 
 public operator fun <V : Vision> VisionContainer<V>.get(str: String): V? = get(Name.parse(str))
 

visionforge-core/src/commonMain/kotlin/space/kscience/visionforge/VisionGroupBase.kt

@@ -1,13 +1,12 @@
 package space.kscience.visionforge
 
-import kotlinx.coroutines.GlobalScope
-import kotlinx.coroutines.flow.MutableSharedFlow
-import kotlinx.coroutines.flow.SharedFlow
-import kotlinx.coroutines.launch
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.Transient
 import space.kscience.dataforge.names.*
+import kotlin.jvm.Synchronized
+
+private class StructureChangeListener(val owner: Any?, val callback: VisionGroup.(Name) -> Unit)
 
 /**
  * Abstract implementation of mutable group of [Vision]
@@ -40,16 +39,24 @@ public open class VisionGroupBase(
     }
 
     @Transient
-    private val _structureChanges: MutableSharedFlow<MutableVisionGroup.StructureChange> = MutableSharedFlow()
+    private val structureListeners = HashSet<StructureChangeListener>()
 
-    override val structureChanges: SharedFlow<MutableVisionGroup.StructureChange> get() = _structureChanges
+    @Synchronized
+    override fun onStructureChanged(owner: Any?, block: VisionGroup.(Name) -> Unit) {
+        structureListeners.add(StructureChangeListener(owner, block))
+    }
+
+    @Synchronized
+    override fun removeStructureListener(owner: Any?) {
+        structureListeners.removeAll { it.owner == owner }
+    }
 
     /**
      * Propagate children change event upwards
      */
-    private fun childrenChanged(name: NameToken, before: Vision?, after: Vision?) {
+    protected fun childrenChanged(name: Name) {
-        (manager?.context?: GlobalScope).launch {
+        structureListeners.forEach {
-            _structureChanges.emit(MutableVisionGroup.StructureChange(name, before, after))
+            it.callback(this, name)
         }
     }
 
@@ -83,7 +90,12 @@ public open class VisionGroupBase(
             }
         }
         if (before != child) {
-            childrenChanged(token, before, child)
+            childrenChanged(token.asName())
+            if (child is MutableVisionGroup) {
+                child.onStructureChanged(this) { changedName ->
+                    this@VisionGroupBase.childrenChanged(token + changedName)
+                }
+            }
         }
     }
 

visionforge-solid/src/commonTest/kotlin/space/kscience/visionforge/solid/VisionUpdateTest.kt

@@ -49,28 +49,4 @@ class VisionUpdateTest {
         val reconstructed = visionManager.jsonFormat.decodeFromString(VisionChange.serializer(), serialized)
         assertEquals(change.properties,reconstructed.properties)
     }
-
-    @Test
-    fun testDeserialization(){
-        val str = """
-            {
-                "propertyChange": {
-                    "layer[4]": {
-                        "material": {
-                            "color": 123
-                        }
-                    },
-                    "layer[2]": {
-                        "material": {
-                        }
-                    }
-                },
-                "childrenChange": {
-                }
-            }
-        """.trimIndent()
-
-        val reconstructed = visionManager.jsonFormat.decodeFromString(VisionChange.serializer(), str)
-    }
-
 }

visionforge-threejs/src/main/kotlin/space/kscience/visionforge/solid/three/ThreePlugin.kt

@@ -2,8 +2,6 @@ package space.kscience.visionforge.solid.three
 
 import info.laht.threekt.core.Object3D
 import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.flow.launchIn
-import kotlinx.coroutines.flow.onEach
 import org.w3c.dom.Element
 import org.w3c.dom.HTMLElement
 import space.kscience.dataforge.context.*
@@ -15,6 +13,7 @@ import space.kscience.visionforge.Vision
 import space.kscience.visionforge.onPropertyChange
 import space.kscience.visionforge.solid.*
 import space.kscience.visionforge.solid.specifications.Canvas3DOptions
+import space.kscience.visionforge.solid.three.set
 import space.kscience.visionforge.visible
 import kotlin.collections.set
 import kotlin.reflect.KClass
@@ -82,9 +81,11 @@ public class ThreePlugin : AbstractPlugin(), ElementVisionRenderer {
                     }
                 }
 
-                obj.structureChanges.onEach { (nameToken, _, child) ->
+                obj.onStructureChanged(this){ childName ->
+                    val child = get(childName)
+
                     //removing old object
-                    findChild(nameToken.asName())?.let { oldChild ->
+                    findChild(childName)?.let { oldChild ->
                         oldChild.parent?.remove(oldChild)
                     }
 
@@ -92,12 +93,12 @@ public class ThreePlugin : AbstractPlugin(), ElementVisionRenderer {
                     if (child != null && child is Solid) {
                         try {
                             val object3D = buildObject3D(child)
-                            set(nameToken, object3D)
+                            set(childName, object3D)
                         } catch (ex: Throwable) {
                             logger.error(ex) { "Failed to render $child" }
                         }
                     }
-                }.launchIn(updateScope)
+                }
             }
         }
         is Composite -> compositeFactory(this, obj)