diff --git a/visionforge-core/src/commonMain/kotlin/hep/dataforge/vision/Colors.kt b/visionforge-core/src/commonMain/kotlin/hep/dataforge/vision/Colors.kt
index 9c76fd81..7dc41632 100644
--- a/visionforge-core/src/commonMain/kotlin/hep/dataforge/vision/Colors.kt
+++ b/visionforge-core/src/commonMain/kotlin/hep/dataforge/vision/Colors.kt
@@ -5,6 +5,7 @@ import hep.dataforge.meta.get
 import hep.dataforge.meta.number
 import hep.dataforge.values.ValueType
 import hep.dataforge.values.int
+import hep.dataforge.values.string
 import kotlin.math.max
 
 /**
diff --git a/visionforge-fx/src/main/kotlin/hep/dataforge/vision/editor/ColorValueChooser.kt b/visionforge-fx/src/main/kotlin/hep/dataforge/vision/editor/ColorValueChooser.kt
index 5f4e2573..3487f95c 100644
--- a/visionforge-fx/src/main/kotlin/hep/dataforge/vision/editor/ColorValueChooser.kt
+++ b/visionforge-fx/src/main/kotlin/hep/dataforge/vision/editor/ColorValueChooser.kt
@@ -6,6 +6,7 @@ import hep.dataforge.names.asName
 import hep.dataforge.values.Null
 import hep.dataforge.values.Value
 import hep.dataforge.values.asValue
+import hep.dataforge.values.string
 import javafx.scene.control.ColorPicker
 import javafx.scene.paint.Color
 import org.slf4j.LoggerFactory
diff --git a/visionforge-fx/src/main/kotlin/hep/dataforge/vision/editor/ComboBoxValueChooser.kt b/visionforge-fx/src/main/kotlin/hep/dataforge/vision/editor/ComboBoxValueChooser.kt
index 051469c7..5ce3d960 100644
--- a/visionforge-fx/src/main/kotlin/hep/dataforge/vision/editor/ComboBoxValueChooser.kt
+++ b/visionforge-fx/src/main/kotlin/hep/dataforge/vision/editor/ComboBoxValueChooser.kt
@@ -12,6 +12,7 @@ import hep.dataforge.names.Name
 import hep.dataforge.names.asName
 import hep.dataforge.values.Value
 import hep.dataforge.values.parseValue
+import hep.dataforge.values.string
 import javafx.collections.FXCollections
 import javafx.scene.control.ComboBox
 import javafx.util.StringConverter
diff --git a/visionforge-fx/src/main/kotlin/hep/dataforge/vision/editor/MetaViewer.kt b/visionforge-fx/src/main/kotlin/hep/dataforge/vision/editor/MetaViewer.kt
index ca6edcc2..88079731 100644
--- a/visionforge-fx/src/main/kotlin/hep/dataforge/vision/editor/MetaViewer.kt
+++ b/visionforge-fx/src/main/kotlin/hep/dataforge/vision/editor/MetaViewer.kt
@@ -17,6 +17,7 @@
 package hep.dataforge.vision.editor
 
 import hep.dataforge.meta.Meta
+import hep.dataforge.values.string
 import hep.dataforge.vision.dfIconView
 import javafx.beans.property.SimpleStringProperty
 import javafx.scene.control.TreeItem
diff --git a/visionforge-fx/src/main/kotlin/hep/dataforge/vision/solid/FXMaterials.kt b/visionforge-fx/src/main/kotlin/hep/dataforge/vision/solid/FXMaterials.kt
index a8a62999..9ae8fcf3 100644
--- a/visionforge-fx/src/main/kotlin/hep/dataforge/vision/solid/FXMaterials.kt
+++ b/visionforge-fx/src/main/kotlin/hep/dataforge/vision/solid/FXMaterials.kt
@@ -6,6 +6,7 @@ import hep.dataforge.meta.get
 import hep.dataforge.meta.int
 import hep.dataforge.values.ValueType
 import hep.dataforge.values.int
+import hep.dataforge.values.string
 import hep.dataforge.vision.Colors
 import javafx.scene.paint.Color
 import javafx.scene.paint.Material
@@ -59,7 +60,7 @@ public fun MetaItem<*>.color(opacity: Double = 1.0): Color {
 /**
  * Infer FX material based on meta item
  */
-fun MetaItem<*>?.material(): Material {
+public fun MetaItem<*>?.material(): Material {
     return when (this) {
         null -> FXMaterials.GREY
         is MetaItem.ValueItem -> PhongMaterial(color())
diff --git a/visionforge-threejs/src/main/kotlin/hep/dataforge/vision/solid/three/ThreeMaterials.kt b/visionforge-threejs/src/main/kotlin/hep/dataforge/vision/solid/three/ThreeMaterials.kt
index 16d24525..f7ec681d 100644
--- a/visionforge-threejs/src/main/kotlin/hep/dataforge/vision/solid/three/ThreeMaterials.kt
+++ b/visionforge-threejs/src/main/kotlin/hep/dataforge/vision/solid/three/ThreeMaterials.kt
@@ -3,6 +3,7 @@ package hep.dataforge.vision.solid.three
 import hep.dataforge.meta.*
 import hep.dataforge.values.ValueType
 import hep.dataforge.values.int
+import hep.dataforge.values.string
 import hep.dataforge.vision.Colors
 import hep.dataforge.vision.Vision
 import hep.dataforge.vision.solid.SolidMaterial