CHANGELOG.md

@@ -3,8 +3,10 @@
 ## [Unreleased]
 ### Added
 - Server module
+- Change collector
 
 ### Changed
+- Vision does not implement ItemProvider anymore. Property changes are done via `getProperty`/`setProperty` and `property` delegate.
 
 ### Deprecated
 

build.gradle.kts

@@ -4,8 +4,8 @@ plugins {
     id("ru.mipt.npm.project")
 }
 
-val dataforgeVersion by extra("0.2.0-dev-4")
+val dataforgeVersion by extra("0.2.0-dev-7")
-val ktorVersion by extra("1.4.1")
+val ktorVersion by extra("1.4.2")
 val kotlinWrappersVersion by extra("pre.129-kotlin-1.4.10")
 
 allprojects {

visionforge-core/src/commonMain/kotlin/hep/dataforge/vision/AbstractVisionGroup.kt

@@ -1,8 +1,5 @@
 package hep.dataforge.vision
 
-import hep.dataforge.meta.Meta
-import hep.dataforge.meta.get
-import hep.dataforge.meta.node
 import hep.dataforge.names.*
 import kotlinx.serialization.Transient
 
@@ -10,7 +7,7 @@ import kotlinx.serialization.Transient
 /**
  * Abstract implementation of mutable group of [Vision]
  */
-public abstract class AbstractVisionGroup : AbstractVision(), MutableVisionGroup {
+public abstract class AbstractVisionGroup : VisionBase(), MutableVisionGroup {
 
     //protected abstract val _children: MutableMap<NameToken, T>
 
@@ -19,13 +16,13 @@ public abstract class AbstractVisionGroup : AbstractVision(), MutableVisionGroup
      */
     abstract override val children: Map<NameToken, Vision>
 
-    abstract override var styleSheet: StyleSheet?
+    final override var styleSheet: StyleSheet? = null
-        protected set
+        private set
 
     /**
      * Update or create stylesheet
      */
-    public fun styleSheet(block: StyleSheet.() -> Unit) {
+    public open fun styleSheet(block: StyleSheet.() -> Unit) {
         if (styleSheet == null) {
             styleSheet = StyleSheet(this@AbstractVisionGroup)
         }
@@ -84,17 +81,18 @@ public abstract class AbstractVisionGroup : AbstractVision(), MutableVisionGroup
      * Add a static child. Statics could not be found by name, removed or replaced. Changing statics also do not trigger events.
      */
     protected open fun addStatic(child: Vision): Unit {
-        setChild(NameToken("@static", index = child.hashCode().toString()), child)
+        attach(NameToken("@static", index = child.hashCode().toString()), child)
     }
 
     protected abstract fun createGroup(): AbstractVisionGroup
 
     /**
-     * Set this node as parent for given node
+     * Set parent for given child and attach it
      */
-    protected fun attach(child: Vision) {
+    protected fun attach(token: NameToken, child: Vision) {
         if (child.parent == null) {
             child.parent = this
+            setChild(token, child)
         } else if (child.parent !== this) {
             error("Can't reassign existing parent for $child")
         }
@@ -110,8 +108,7 @@ public abstract class AbstractVisionGroup : AbstractVision(), MutableVisionGroup
                 val token = name.tokens.first()
                 when (val current = children[token]) {
                     null -> createGroup().also { child ->
-                        attach(child)
+                        attach(token, child)
-                        setChild(token, child)
                     }
                     is AbstractVisionGroup -> current
                     else -> error("Can't create group with name $name because it exists and not a group")
@@ -129,7 +126,6 @@ public abstract class AbstractVisionGroup : AbstractVision(), MutableVisionGroup
         when {
             name.isEmpty() -> {
                 if (child != null) {
-                    attach(child)
                     addStatic(child)
                 }
             }
@@ -138,8 +134,7 @@ public abstract class AbstractVisionGroup : AbstractVision(), MutableVisionGroup
                 if (child == null) {
                     removeChild(token)
                 } else {
-                    attach(child)
+                    attach(token, child)
-                    setChild(token, child)
                 }
                 childrenChanged(token, child)
             }
@@ -151,11 +146,23 @@ public abstract class AbstractVisionGroup : AbstractVision(), MutableVisionGroup
         }
     }
 
-    override fun update(meta: Meta) {
+    override fun update(change: Vision) {
-        val styleMeta = meta.get("styleSheet").node
+        if (change is VisionGroup) {
-        if (styleMeta != null) {
+            //update stylesheet
-            this.styleSheet?.update(styleMeta)
+            val changeStyleSheet = change.styleSheet
-        }
+            if (changeStyleSheet != null) {
-        super.update(meta)
+                styleSheet {
+                    update(changeStyleSheet)
+                }
+            }
+            change.children.forEach { (token, child) ->
+                when {
+                    child is NullVision -> removeChild(token)
+                    children.containsKey(token) -> children[token]!!.update(child)
+                    else -> attach(token, child)
+                }
+            }
+        }
+        super.update(change)
     }
 }

visionforge-core/src/commonMain/kotlin/hep/dataforge/vision/SimpleVisionGroup.kt

@@ -1,17 +1,13 @@
 package hep.dataforge.vision
 
-import hep.dataforge.meta.Config
 import hep.dataforge.names.NameToken
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 
 
 @Serializable
-@SerialName("group")
+@SerialName("vision.group")
 public class SimpleVisionGroup : AbstractVisionGroup() {
-
-    override var styleSheet: StyleSheet? = null
-
     @SerialName("children")
     private val _children = HashMap<NameToken, Vision>()
     override val children: Map<NameToken, Vision> get() = _children

visionforge-core/src/commonMain/kotlin/hep/dataforge/vision/StyleSheet.kt

@@ -5,7 +5,10 @@ package hep.dataforge.vision
 import hep.dataforge.meta.*
 import hep.dataforge.names.Name
 import hep.dataforge.names.asName
-import kotlinx.serialization.*
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.Serializable
+import kotlinx.serialization.Transient
+import kotlinx.serialization.UseSerializers
 import kotlinx.serialization.builtins.MapSerializer
 import kotlinx.serialization.builtins.serializer
 import kotlinx.serialization.descriptors.SerialDescriptor
@@ -15,7 +18,7 @@ import kotlinx.serialization.encoding.Encoder
 /**
  * A container for styles
  */
-@Serializable
+@Serializable(StyleSheet.Companion::class)
 public class StyleSheet private constructor(private val styleMap: MutableMap<String, Meta>) {
     @Transient
     internal var owner: Vision? = null
@@ -30,7 +33,8 @@ public class StyleSheet private constructor(private val styleMap: MutableMap<Str
     private fun Vision.styleChanged(key: String, oldStyle: Meta?, newStyle: Meta?) {
         if (styles.contains(key)) {
             //TODO optimize set concatenation
-            val tokens: Collection<Name> = ((oldStyle?.items?.keys ?: emptySet()) + (newStyle?.items?.keys ?: emptySet()))
+            val tokens: Collection<Name> =
+                ((oldStyle?.items?.keys ?: emptySet()) + (newStyle?.items?.keys ?: emptySet()))
                     .map { it.asName() }
             tokens.forEach { parent?.propertyChanged(it) }
         }
@@ -73,8 +77,17 @@ public class StyleSheet private constructor(private val styleMap: MutableMap<Str
         set(key, newStyle.seal())
     }
 
-    @ExperimentalSerializationApi
+    public fun update(key: String, meta: Meta) {
-    @Serializer(StyleSheet::class)
+        val existing = get(key)
+        set(key, existing?.edit { this.update(meta) } ?: meta)
+    }
+
+    public fun update(other: StyleSheet) {
+        other.items.forEach { (key, value) ->
+            update(key, value)
+        }
+    }
+
     public companion object : KSerializer<StyleSheet> {
         private val mapSerializer = MapSerializer(String.serializer(), MetaSerializer)
         override val descriptor: SerialDescriptor get() = mapSerializer.descriptor
@@ -91,11 +104,6 @@ public class StyleSheet private constructor(private val styleMap: MutableMap<Str
     }
 }
 
-public fun StyleSheet.update(styleMeta: Meta){
-    TODO()
-}
-
-
 /**
  * Add style name to the list of styles to be resolved later. The style with given name does not necessary exist at the moment.
  */

visionforge-core/src/commonMain/kotlin/hep/dataforge/vision/Vision.kt

@@ -1,6 +1,7 @@
 package hep.dataforge.vision
 
 import hep.dataforge.meta.*
+import hep.dataforge.meta.descriptors.Described
 import hep.dataforge.names.Name
 import hep.dataforge.names.asName
 import hep.dataforge.names.toName
@@ -9,14 +10,15 @@ import hep.dataforge.values.asValue
 import hep.dataforge.vision.Vision.Companion.TYPE
 import hep.dataforge.vision.Vision.Companion.VISIBLE_KEY
 import kotlinx.serialization.PolymorphicSerializer
-import kotlinx.serialization.Serializable
 import kotlinx.serialization.Transient
+import kotlin.properties.ReadWriteProperty
+import kotlin.reflect.KProperty
 
 /**
  * A root type for display hierarchy
  */
 @Type(TYPE)
-public interface Vision : Configurable {
+public interface Vision : Configurable, Described {
 
     /**
      * The parent object of this one. If null, this one is a root.
@@ -37,12 +39,7 @@ public interface Vision : Configurable {
     /**
      * Get property (including styles). [inherit] toggles parent node property lookup
      */
-    public fun getProperty(name: Name, inherit: Boolean): MetaItem<*>?
+    public fun getProperty(name: Name, inherit: Boolean = true): MetaItem<*>?
-
-    /**
-     * Ger a property including inherited values
-     */
-    override fun getItem(name: Name): MetaItem<*>? = getProperty(name, true)
 
     /**
      * Trigger property invalidation event. If [name] is empty, notify that the whole object is changed
@@ -71,7 +68,7 @@ public interface Vision : Configurable {
     /**
      * Update this vision using external meta. Children are not updated.
      */
-    public fun update(meta: Meta)
+    public fun update(change: Vision)
 
     public companion object {
         public const val TYPE: String = "vision"
@@ -89,16 +86,61 @@ public interface Vision : Configurable {
 public fun Vision.getProperty(key: String, inherit: Boolean = true): MetaItem<*>? =
     getProperty(key.toName(), inherit)
 
+/**
+ * A convenience method to pair [getProperty]
+ */
+public fun Vision.setProperty(key: Name, value: Any?) {
+    config[key] = value
+}
+
+/**
+ * A convenience method to pair [getProperty]
+ */
+public fun Vision.setProperty(key: String, value: Any?) {
+    config[key] = value
+}
+
 /**
  * Find a style with given name for given [Vision]. The style is not necessary applied to this [Vision].
  */
 public tailrec fun Vision.resolveStyle(name: String): Meta? =
     (this as? VisionGroup)?.styleSheet?.get(name) ?: parent?.resolveStyle(name)
 
-
 /**
  * Control visibility of the element
  */
 public var Vision.visible: Boolean?
-    get() = getItem(VISIBLE_KEY).boolean
+    get() = getProperty(VISIBLE_KEY).boolean
-    set(value) = setItem(VISIBLE_KEY, value?.asValue())
+    set(value) = config.setValue(VISIBLE_KEY, value?.asValue())
+
+/**
+ * Convinience delegate for properties
+ */
+public fun Vision.property(
+    default: MetaItem<*>? = null,
+    key: Name? = null,
+    inherit: Boolean = true,
+): MutableItemDelegate =
+    object : ReadWriteProperty<Any?, MetaItem<*>?> {
+        override fun getValue(thisRef: Any?, property: KProperty<*>): MetaItem<*>? {
+            val name = key ?: property.name.toName()
+            return getProperty(name, inherit) ?: default
+        }
+
+        override fun setValue(thisRef: Any?, property: KProperty<*>, value: MetaItem<*>?) {
+            val name = key ?: property.name.toName()
+            setProperty(name, value)
+        }
+    }
+
+//TODO replace by value
+fun Vision.properties(inherit: Boolean = true): MutableItemProvider = object : MutableItemProvider {
+    override fun getItem(name: Name): MetaItem<*>? {
+        return getProperty(name, inherit)
+    }
+
+    override fun setItem(name: Name, item: MetaItem<*>?) {
+        setProperty(name, item)
+    }
+
+}

visionforge-core/src/commonMain/kotlin/hep/dataforge/vision/VisionBase.kt

@@ -2,20 +2,24 @@ package hep.dataforge.vision
 
 import hep.dataforge.meta.*
 import hep.dataforge.meta.descriptors.NodeDescriptor
+import hep.dataforge.meta.descriptors.defaultItem
+import hep.dataforge.meta.descriptors.get
 import hep.dataforge.names.Name
 import hep.dataforge.names.asName
 import hep.dataforge.values.ValueType
 import hep.dataforge.vision.Vision.Companion.STYLE_KEY
+import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.Transient
 
 internal data class PropertyListener(
     val owner: Any? = null,
-    val action: (name: Name) -> Unit
+    val action: (name: Name) -> Unit,
 )
 
 @Serializable
-public open class AbstractVision : Vision {
+@SerialName("vision")
+public open class VisionBase : Vision {
 
     @Transient
     override var parent: VisionGroup? = null
@@ -26,6 +30,8 @@ public open class AbstractVision : Vision {
     override var properties: Config? = null
         protected set
 
+    override val descriptor: NodeDescriptor? get() = null
+
     protected fun updateStyles(names: List<String>) {
         names.mapNotNull { resolveStyle(it) }.asSequence()
             .flatMap { it.items.asSequence() }
@@ -76,12 +82,14 @@ public open class AbstractVision : Vision {
             sequence {
                 yield(properties?.get(name))
                 yieldAll(getStyleItems(name))
+                yield(descriptor?.get(name)?.defaultItem())
                 yield(parent?.getProperty(name, inherit))
             }.merge()
         } else {
             sequence {
                 yield(properties?.get(name))
                 yieldAll(getStyleItems(name))
+                yield(descriptor?.get(name)?.defaultItem())
             }.merge()
         }
     }
@@ -94,8 +102,10 @@ public open class AbstractVision : Vision {
         properties = null
     }
 
-    override fun update(meta: Meta) {
+    override fun update(change: Vision) {
-        meta[Vision::properties.name].node?.let { configure(it) }
+        if (change.properties != null) {
+            config.update(change.config)
+        }
     }
 
     public companion object {

visionforge-core/src/commonMain/kotlin/hep/dataforge/vision/VisionChange.kt

@@ -1,50 +0,0 @@
-package hep.dataforge.vision
-
-import hep.dataforge.meta.Config
-import hep.dataforge.meta.Meta
-import hep.dataforge.meta.get
-import hep.dataforge.meta.set
-import hep.dataforge.names.NameToken
-import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.flow.Flow
-import kotlinx.coroutines.sync.Mutex
-
-
-//public class VisionChange(public val properties: Meta, public val childrenChange: Map<NameToken, VisionChange>)
-
-public class VisionChangeCollector(
-    public val manager: VisionManager,
-    public val scope: CoroutineScope,
-    public val vision: Vision,
-    public val lock: Mutex = Mutex()
-) {
-    private val collector: Config = Config()
-    private val childrenCollectors = HashMap<NameToken, VisionChangeCollector>()
-
-    init {
-        vision.onPropertyChange(this) { propertyName ->
-            collector[propertyName] = vision.properties?.get(propertyName)
-        }
-        if (vision is VisionGroup) {
-            vision.children.forEach { (token, child) ->
-                childrenCollectors[token] = VisionChangeCollector(manager, scope, child, lock)
-            }
-        }
-        if (vision is MutableVisionGroup) {
-            TODO("Tread vision structure change")
-//            vision.onChildrenChange(this) { childName, child ->
-//                if(child == null){
-//                    childrenCollectors[childName] = null
-//                } else {
-//                    childrenCollectors[childName] = manager.encodeToMeta(child)
-//                }
-//            }
-        }
-    }
-}
-//
-//fun collectUpdates(manager: VisionManager, scope: CoroutineScope, vision: Vision): Flow<Meta> {
-//
-//
-//    vision.
-//}

visionforge-core/src/commonMain/kotlin/hep/dataforge/vision/VisionManager.kt

@@ -3,10 +3,6 @@ package hep.dataforge.vision
 import hep.dataforge.context.*
 import hep.dataforge.meta.*
 import hep.dataforge.meta.descriptors.NodeDescriptor
-import hep.dataforge.names.asName
-import hep.dataforge.values.Null
-import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.flow.Flow
 import kotlinx.serialization.json.Json
 import kotlinx.serialization.json.JsonElement
 import kotlinx.serialization.modules.SerializersModule
@@ -52,30 +48,30 @@ public class VisionManager(meta: Meta) : AbstractPlugin(meta) {
         encodeToJsonElement(vision).toMetaItem(descriptor).node
             ?: error("Expected node, but value found. Check your serializer!")
 
-    public fun updateVision(vision: Vision, meta: Meta) {
+//    public fun updateVision(vision: Vision, meta: Meta) {
-        vision.update(meta)
+//        vision.update(meta)
-        if (vision is MutableVisionGroup) {
+//        if (vision is MutableVisionGroup) {
-            val children by meta.node()
+//            val children by meta.node()
-            children?.items?.forEach { (token, item) ->
+//            children?.items?.forEach { (token, item) ->
-                when {
+//                when {
-                    item.value == Null -> vision[token] = null //Null means removal
+//                    item.value == Null -> vision[token] = null //Null means removal
-                    item.node != null -> {
+//                    item.node != null -> {
-                        val node = item.node!!
+//                        val node = item.node!!
-                        val type by node.string()
+//                        val type by node.string()
-                        if (type != null) {
+//                        if (type != null) {
-                            //If the type is present considering it as new node, not an update
+//                            //If the type is present considering it as new node, not an update
-                            vision[token.asName()] = decodeFromMeta(node)
+//                            vision[token.asName()] = decodeFromMeta(node)
-                        } else {
+//                        } else {
-                            val existing = vision.children[token]
+//                            val existing = vision.children[token]
-                            if (existing != null) {
+//                            if (existing != null) {
-                                updateVision(existing, node)
+//                                updateVision(existing, node)
-                            }
+//                            }
-                        }
+//                        }
-                    }
+//                    }
-                }
+//                }
-            }
+//            }
-        }
+//        }
-    }
+//    }
 
     public companion object : PluginFactory<VisionManager> {
         override val tag: PluginTag = PluginTag(name = "vision", group = PluginTag.DATAFORGE_GROUP)

visionforge-core/src/commonMain/kotlin/hep/dataforge/vision/collectChange.kt

@@ -0,0 +1,106 @@
+package hep.dataforge.vision
+
+import hep.dataforge.meta.*
+import hep.dataforge.meta.descriptors.ItemDescriptor
+import hep.dataforge.names.Name
+import hep.dataforge.names.NameToken
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.flow
+import kotlinx.coroutines.launch
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+import kotlin.time.Duration
+
+/**
+ * An empty vision existing only for Vision tree change representation. [NullVision] should not be used outside update logic.
+ */
+@Serializable
+@SerialName("vision.null")
+public object NullVision : Vision {
+
+    @Suppress("SetterBackingFieldAssignment")
+    override var parent: VisionGroup? = null
+        set(value) {
+            //do nothing
+        }
+
+    override val properties: Config? = null
+
+    override fun getAllProperties(): Laminate = Laminate(Meta.EMPTY)
+
+    override fun getProperty(name: Name, inherit: Boolean): MetaItem<*>? = null
+
+    override fun propertyChanged(name: Name) {}
+
+    override fun onPropertyChange(owner: Any?, action: (Name) -> Unit) {}
+
+    override fun removeChangeListener(owner: Any?) {}
+
+    override fun update(change: Vision) {
+        error("Null vision should be removed, not updated")
+    }
+
+    override val config: Config get() = Config()
+    override val descriptor: ItemDescriptor? get() = null
+}
+
+private fun Vision.collectChange(scope: CoroutineScope, collector: Vision): Job = scope.launch {
+    //Store job to be able to cancel collection jobs
+    //TODO add lock for concurrent modification protection?
+    val jobStore = HashMap<NameToken, Job>()
+
+    if (this is VisionGroup) {
+        check(collector is MutableVisionGroup) { "Collector for a group should be a group" }
+        //Subscribe for children changes
+        children.forEach { (token, child) ->
+            val childCollector: Vision = if (child is VisionGroup) {
+                SimpleVisionGroup()
+            } else {
+                VisionBase()
+            }
+            val job = child.collectChange(this, childCollector)
+            jobStore[token] = job
+            //TODO add lazy child addition
+            collector[token] = childCollector
+        }
+
+        //Subscribe for structure change
+        if (this is MutableVisionGroup) {
+            onChildrenChange(this) { token, child ->
+                //Cancel collector job to avoid leaking
+                jobStore[token]?.cancel()
+                if (child != null) {
+                    //Collect to existing Vision
+                    val job = child.collectChange(this, child)
+                    jobStore[token] = job
+                    collector[token] = child
+                } else{
+                    collector[token] = NullVision
+                }
+            }
+        }
+    }
+
+    //Collect properties change
+    collector.onPropertyChange(collector) { propertyName ->
+        collector.config[propertyName] = properties?.get(propertyName)
+    }
+}
+
+public fun Vision.flowChanges(scope: CoroutineScope, collectionDuration: Duration): Flow<Vision> = flow {
+    //emit initial visual tree
+    emit(this@flowChanges)
+    while (true) {
+        val collector: Vision = if (this is VisionGroup) {
+            SimpleVisionGroup()
+        } else {
+            VisionBase()
+        }
+        val collectorJob = collectChange(scope, collector)
+        kotlinx.coroutines.delay(collectionDuration)
+        emit(collector)
+        collectorJob.cancel()
+    }
+}

visionforge-server/build.gradle.kts

@@ -1,63 +1,8 @@
 //import org.jetbrains.kotlin.gradle.plugin.KotlinCompilation.Companion.MAIN_COMPILATION_NAME
 
 plugins {
-    id("ru.mipt.npm.mpp")
+    id("ru.mipt.npm.jvm")
-//    application
 }
 
 val ktorVersion: String by rootProject.extra
 
-//kscience {
-//    application()
-//}
-
-kotlin {
-//    afterEvaluate {
-//        val jsBrowserDistribution by tasks.getting
-//
-//        jvm {
-//            withJava()
-//            compilations[MAIN_COMPILATION_NAME]?.apply {
-//                tasks.getByName<ProcessResources>(processResourcesTaskName) {
-//                    dependsOn(jsBrowserDistribution)
-//                    afterEvaluate {
-//                        from(jsBrowserDistribution)
-//                    }
-//                }
-//            }
-//
-//        }
-//    }
-
-    sourceSets {
-        commonMain {
-            dependencies {
-                implementation(project(":visionforge-core"))
-            }
-        }
-        jvmMain {
-            dependencies {
-                implementation("io.ktor:ktor-server-cio:$ktorVersion")
-                implementation("io.ktor:ktor-serialization:$ktorVersion")
-            }
-        }
-        jsMain {
-            dependencies {
-                implementation("io.ktor:ktor-client-js:$ktorVersion")
-                implementation("io.ktor:ktor-client-serialization-js:$ktorVersion")
-            }
-        }
-    }
-}
-
-
-//distributions {
-//    main {
-//        contents {
-//            from("$buildDir/libs") {
-//                rename("${rootProject.name}-jvm", rootProject.name)
-//                into("lib")
-//            }
-//        }
-//    }
-//}

visionforge-solid/src/commonMain/kotlin/hep/dataforge/vision/solid/BasicSolid.kt

@@ -1,15 +1,20 @@
 package hep.dataforge.vision.solid
 
-import hep.dataforge.meta.*
+import hep.dataforge.meta.Meta
-import hep.dataforge.vision.AbstractVision
+import hep.dataforge.meta.descriptors.NodeDescriptor
+import hep.dataforge.meta.float
+import hep.dataforge.meta.get
+import hep.dataforge.meta.node
 import hep.dataforge.vision.Vision
+import hep.dataforge.vision.VisionBase
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
-import kotlinx.serialization.UseSerializers
 
 @Serializable
 @SerialName("solid")
-public open class BasicSolid: AbstractVision(), Solid {
+public open class BasicSolid : VisionBase(), Solid {
+    override val descriptor: NodeDescriptor get() = Solid.descriptor
+
     @Serializable(Point3DSerializer::class)
     override var position: Point3D? = null
 
@@ -19,16 +24,16 @@ public open class BasicSolid: AbstractVision(), Solid {
     @Serializable(Point3DSerializer::class)
     override var scale: Point3D? = null
 
-    override fun update(meta: Meta) {
+    override fun update(change: Vision) {
         fun Meta.toVector(default: Float = 0f) = Point3D(
             this[Solid.X_KEY].float ?: default,
             this[Solid.Y_KEY].float ?: default,
             this[Solid.Z_KEY].float ?: default
         )
 
-        meta[Solid.POSITION_KEY].node?.toVector()?.let { position = it }
+        change.properties[Solid.POSITION_KEY].node?.toVector()?.let { position = it }
-        meta[Solid.ROTATION].node?.toVector()?.let { rotation = it }
+        change.properties[Solid.ROTATION].node?.toVector()?.let { rotation = it }
-        meta[Solid.SCALE_KEY].node?.toVector(1f)?.let { scale = it }
+        change.properties[Solid.SCALE_KEY].node?.toVector(1f)?.let { scale = it }
-        super.update(meta)
+        super.update(change)
     }
 }

visionforge-solid/src/commonMain/kotlin/hep/dataforge/vision/solid/PolyLine.kt

@@ -7,6 +7,7 @@ import hep.dataforge.names.Name
 import hep.dataforge.names.asName
 import hep.dataforge.names.plus
 import hep.dataforge.vision.VisionContainerBuilder
+import hep.dataforge.vision.properties
 import hep.dataforge.vision.set
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
@@ -17,7 +18,7 @@ import kotlinx.serialization.UseSerializers
 public class PolyLine(public var points: List<Point3D>) : BasicSolid(), Solid {
 
     //var lineType by string()
-    public var thickness: Number by number(1.0, key = SolidMaterial.MATERIAL_KEY + THICKNESS_KEY)
+    public var thickness: Number by properties().number(1.0, key = SolidMaterial.MATERIAL_KEY + THICKNESS_KEY)
 
     public companion object {
         public val THICKNESS_KEY: Name = "thickness".asName()

visionforge-solid/src/commonMain/kotlin/hep/dataforge/vision/solid/Proxy.kt

@@ -10,14 +10,14 @@ import kotlinx.serialization.Transient
 import kotlin.collections.set
 
 public abstract class AbstractProxy : BasicSolid(), VisionGroup {
-    public abstract val prototype: Vision
+    public abstract val prototype: Solid
 
     override fun getProperty(name: Name, inherit: Boolean): MetaItem<*>? {
         return if (inherit) {
             sequence {
                 yield(properties?.get(name))
                 yieldAll(getStyleItems(name))
-                yield(prototype.getItem(name))
+                yield(prototype.getProperty(name))
                 yield(parent?.getProperty(name, inherit))
             }.merge()
         } else {
@@ -42,7 +42,7 @@ public abstract class AbstractProxy : BasicSolid(), VisionGroup {
         //do nothing
     }
 
-    override val descriptor: NodeDescriptor? get() = prototype.descriptor
+    override val descriptor: NodeDescriptor get() = prototype.descriptor
 }
 
 /**
@@ -82,13 +82,11 @@ public class Proxy private constructor(
         return NameToken(PROXY_CHILD_PROPERTY_PREFIX, childName.toString()) + propertyName
     }
 
-    private fun prototypeFor(name: Name): Vision {
+    private fun prototypeFor(name: Name): Solid {
-        return (prototype as? VisionGroup)?.get(name)
+        return (prototype as? SolidGroup)?.get(name) as? Solid
             ?: error("Prototype with name $name not found in $this")
     }
 
-    override val descriptor: NodeDescriptor? get() = prototype.descriptor
-
     //override fun findAllStyles(): Laminate = Laminate((styles + prototype.styles).mapNotNull { findStyle(it) })
 
     /**
@@ -97,7 +95,7 @@ public class Proxy private constructor(
      */
     public inner class ProxyChild(public val name: Name) : AbstractProxy() {
 
-        override val prototype: Vision get() = prototypeFor(name)
+        override val prototype: Solid get() = prototypeFor(name)
 
         override val styleSheet: StyleSheet get() = this@Proxy.styleSheet
 

visionforge-solid/src/commonMain/kotlin/hep/dataforge/vision/solid/Solid.kt

@@ -14,7 +14,6 @@ import hep.dataforge.vision.enum
 import hep.dataforge.vision.solid.Solid.Companion.DETAIL_KEY
 import hep.dataforge.vision.solid.Solid.Companion.IGNORE_KEY
 import hep.dataforge.vision.solid.Solid.Companion.LAYER_KEY
-import kotlinx.serialization.UseSerializers
 
 /**
  * Interface for 3-dimensional [Vision]
@@ -24,7 +23,7 @@ public interface Solid : Vision {
     public var rotation: Point3D?
     public var scale: Point3D?
 
-    override val descriptor: NodeDescriptor? get() = Companion.descriptor
+    override val descriptor: NodeDescriptor get() = Companion.descriptor
 
     public companion object {
         //        val SELECTED_KEY = "selected".asName()
@@ -123,7 +122,7 @@ public enum class RotationOrder {
  */
 public var Solid.rotationOrder: RotationOrder
     get() = getItem(Solid.ROTATION_ORDER_KEY).enum<RotationOrder>() ?: RotationOrder.XYZ
-    set(value) = setItem(Solid.ROTATION_ORDER_KEY, value.name.asValue())
+    set(value) = setValue(Solid.ROTATION_ORDER_KEY, value.name.asValue())
 
 
 /**
@@ -131,7 +130,7 @@ public var Solid.rotationOrder: RotationOrder
  */
 public var Solid.detail: Int?
     get() = getProperty(DETAIL_KEY, false).int
-    set(value) = setItem(DETAIL_KEY, value?.asValue())
+    set(value) = setValue(DETAIL_KEY, value?.asValue())
 
 /**
  * If this property is true, the object will be ignored on render.
@@ -139,7 +138,7 @@ public var Solid.detail: Int?
  */
 public var Vision.ignore: Boolean?
     get() = getProperty(IGNORE_KEY, false).boolean
-    set(value) = setItem(IGNORE_KEY, value?.asValue())
+    set(value) = setValue(IGNORE_KEY, value?.asValue())
 
 //var VisualObject.selected: Boolean?
 //    get() = getProperty(SELECTED_KEY).boolean

visionforge-solid/src/commonMain/kotlin/hep/dataforge/vision/solid/SolidGroup.kt

@@ -1,16 +1,12 @@
 package hep.dataforge.vision.solid
 
 import hep.dataforge.meta.Config
-import hep.dataforge.meta.DFExperimental
+import hep.dataforge.meta.descriptors.NodeDescriptor
 import hep.dataforge.names.Name
 import hep.dataforge.names.NameToken
-import hep.dataforge.names.asName
 import hep.dataforge.vision.*
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
-import kotlinx.serialization.Serializer
-import kotlinx.serialization.UseSerializers
-import kotlinx.serialization.json.Json
 import kotlin.collections.set
 
 public interface PrototypeHolder {
@@ -25,7 +21,7 @@ public interface PrototypeHolder {
 @SerialName("group.solid")
 public class SolidGroup : AbstractVisionGroup(), Solid, PrototypeHolder {
 
-    override var styleSheet: StyleSheet? = null
+    override val descriptor: NodeDescriptor get() = Solid.descriptor
 
     /**
      * A container for templates visible inside this group
@@ -44,9 +40,6 @@ public class SolidGroup : AbstractVisionGroup(), Solid, PrototypeHolder {
         }).run(builder)
     }
 
-    //FIXME to be lifted to AbstractVisualGroup after https://github.com/Kotlin/kotlinx.serialization/issues/378 is fixed
-    override var properties: Config? = null
-
     @Serializable(Point3DSerializer::class)
     override var position: Point3D? = null
 
@@ -111,12 +104,10 @@ public fun MutableVisionGroup.group(name: String, action: SolidGroup.() -> Unit
  * A special class which works as a holder for prototypes
  */
 internal class Prototypes(
-    override var children: MutableMap<NameToken, Vision> = LinkedHashMap()
+    override var children: MutableMap<NameToken, Vision> = LinkedHashMap(),
 ) : AbstractVisionGroup(), MutableVisionGroup, PrototypeHolder {
 
-    override var styleSheet: StyleSheet?
+    override fun styleSheet(block: StyleSheet.() -> Unit) {
-        get() = null
-        set(_) {
         error("Can't define stylesheet for prototypes block")
     }
 

visionforge-solid/src/commonMain/kotlin/hep/dataforge/vision/solid/serialization.kt

@@ -1,12 +1,8 @@
 package hep.dataforge.vision.solid
 
-import hep.dataforge.meta.DFExperimental
-import hep.dataforge.meta.double
-import hep.dataforge.meta.transformations.MetaConverter.Companion.double
 import hep.dataforge.names.NameToken
 import hep.dataforge.vision.MutableVisionGroup
 import hep.dataforge.vision.Vision
-import hep.dataforge.vision.VisionGroup
 import kotlinx.serialization.*
 import kotlinx.serialization.builtins.MapSerializer
 import kotlinx.serialization.builtins.nullable
@@ -18,7 +14,6 @@ import kotlinx.serialization.encoding.*
 
 
 @OptIn(ExperimentalSerializationApi::class)
-@Serializer(Point3D::class)
 public object Point3DSerializer : KSerializer<Point3D> {
     override val descriptor: SerialDescriptor = buildClassSerialDescriptor("hep.dataforge.vis.spatial.Point3D") {
         element<Double>("x")
@@ -54,7 +49,6 @@ public object Point3DSerializer : KSerializer<Point3D> {
 }
 
 @OptIn(ExperimentalSerializationApi::class)
-@Serializer(Point2D::class)
 public object Point2DSerializer : KSerializer<Point2D> {
     override val descriptor: SerialDescriptor = buildClassSerialDescriptor("hep.dataforge.vis.spatial.Point2D") {
         element<Double>("x")
@@ -85,8 +79,6 @@ public object Point2DSerializer : KSerializer<Point2D> {
     }
 }
 
-@OptIn(ExperimentalSerializationApi::class)
-@Serializer(MutableVisionGroup::class)
 internal object PrototypesSerializer : KSerializer<MutableVisionGroup> {
 
     private val mapSerializer: KSerializer<Map<NameToken, Vision>> =