Change the working of groups

demo/maps/src/jvmMain/kotlin/Main.kt

@@ -63,6 +63,8 @@ fun App() {
         ) {
 
             geoJson(URL("https://raw.githubusercontent.com/ggolikov/cities-comparison/master/src/moscow.geo.json"))
+                .withAttribute(ColorAttribute, Color.Blue)
+                .withAttribute(AlphaAttribute, 0.4f)
 
             image(pointOne, Icons.Filled.Home)
 
@@ -117,7 +119,16 @@ fun App() {
 
             visit { id, feature ->
                 if (feature is PolygonFeature) {
-                    (id as FeatureId<PolygonFeature<Gmc>>).onHover {
+                    id as FeatureId<PolygonFeature<Gmc>>
+                    id.onClick {
+                        println("Click on $id")
+                        points(
+                            feature.points,
+                            id = "selected",
+                            attributes = Attributes(ZAttribute, 10f)
+                        ).color(Color.Blue)
+                    }
+                    id.onHover {
                         println("Hover on $id")
                         points(
                             feature.points,

maps-kt-compose/src/jvmMain/kotlin/center/sciprog/maps/compose/MapViewJvm.kt

@@ -120,7 +120,8 @@ public actual fun MapView(
                 )
             }
 
-            featuresState.features.filter { viewPoint.zoom in it.zoomRange }
+            featuresState.features
+                .filter { viewPoint.zoom in it.zoomRange }
                 .forEach { feature ->
                     drawFeature(mapState, painterCache, feature)
                 }

maps-kt-features/src/commonMain/kotlin/center/sciprog/maps/features/Attributes.kt

@@ -9,7 +9,7 @@ public value class Attributes internal constructor(internal val map: Map<Attribu
     @Suppress("UNCHECKED_CAST")
     public operator fun <T> get(attribute: Attribute<T>): T? = map[attribute] as? T
 
-    public fun <T> Attribute<T>.invoke(value: T?): Attributes = withAttribute(this, value)
+    public operator fun <T> Attribute<T>.invoke(value: T?): Attributes = withAttribute(this, value)
 
     override fun toString(): String = "AttributeMap(value=${map.entries})"
 

maps-kt-features/src/commonMain/kotlin/center/sciprog/maps/features/Feature.kt

@@ -132,8 +132,10 @@ public data class PolygonFeature<T : Any>(
 
     override fun getBoundingBox(zoom: Float): Rectangle<T>? = boundingBox
 
-    override fun contains(viewPoint: ViewPoint<T>): Boolean =
+    override fun contains(viewPoint: ViewPoint<T>): Boolean {
-        viewPoint.focus in boundingBox!!//with(space) { viewPoint.focus.isInsidePolygon(points) }
+        val boundingBox = boundingBox ?: return false
+        return viewPoint.focus in boundingBox && with(space) { viewPoint.focus.isInsidePolygon(points) }
+    }
 
     override fun withAttributes(modify: (Attributes) -> Attributes): Feature<T> = copy(attributes = modify(attributes))
 }

maps-kt-features/src/commonMain/kotlin/center/sciprog/maps/features/FeatureGroup.kt

@@ -81,6 +81,11 @@ public data class FeatureGroup<T : Any>(
         feature(this, get(this).withAttributes(modify))
     }
 
+    public fun <F : Feature<T>> FeatureId<F>.withAttributes(modify: Attributes.() -> Attributes): FeatureId<F> {
+        feature(this, get(this).withAttributes(modify))
+        return this
+    }
+
     public fun <F : Feature<T>, V> FeatureId<F>.withAttribute(key: Attribute<V>, value: V?): FeatureId<F> {
         feature(this, get(this).withAttributes { withAttribute(key, value) })
         return this
@@ -174,6 +179,7 @@ public data class FeatureGroup<T : Any>(
 
     public fun <F : Feature<T>> FeatureId<F>.color(color: Color): FeatureId<F> =
         withAttribute(ColorAttribute, color)
+
     public fun <F : Feature<T>> FeatureId<F>.zoomRange(range: FloatRange): FeatureId<F> =
         withAttribute(ZoomRangeAttribute, range)
 
@@ -181,7 +187,7 @@ public data class FeatureGroup<T : Any>(
         featureMap.values.mapNotNull { it.getBoundingBox(zoom) }.wrapRectangles()
     }
 
-    override fun withAttributes(modify: Attributes.() -> Attributes): Feature<T> = copy(attributes = attributes)
+    override fun withAttributes(modify: Attributes.() -> Attributes): Feature<T> = copy(attributes = modify(attributes))
 
     public companion object {
 

maps-kt-features/src/jvmMain/kotlin/center/sciprog/maps/features/drawFeature.kt

@@ -98,7 +98,9 @@ public fun <T : Any> DrawScope.drawFeature(
 
         is FeatureGroup -> {
             feature.featureMap.values.forEach {
-                drawFeature(state, painterCache, it)
+                drawFeature(state, painterCache, it.withAttributes {
+                    feature.attributes + this
+                })
             }
         }
 

maps-kt-geojson/src/commonMain/kotlin/center/sciprog/maps/geojson/geoJsonFeature.kt

@@ -53,15 +53,13 @@ public fun FeatureGroup<Gmc>.geoJsonGeometry(
             geoJsonGeometry(it)
         }
     }
-}.apply {
-    withAttribute(AlphaAttribute, 0.5f)
 }
 
 public fun FeatureGroup<Gmc>.geoJsonFeature(
     geoJson: GeoJsonFeature,
     id: String? = null,
-): FeatureId<Feature<Gmc>>? {
+): FeatureId<Feature<Gmc>> {
-    val geometry = geoJson.geometry ?: return null
+    val geometry = geoJson.geometry ?: return group{}
     val idOverride = geoJson.properties?.get("id")?.jsonPrimitive?.contentOrNull ?: id
     val colorOverride = geoJson.properties?.get("color")?.jsonPrimitive?.intOrNull?.let { Color(it) }
     val jsonGeometry =  geoJsonGeometry(geometry, idOverride)
@@ -75,7 +73,7 @@ public fun FeatureGroup<Gmc>.geoJsonFeature(
 public fun FeatureGroup<Gmc>.geoJson(
     geoJson: GeoJson,
     id: String? = null,
-): FeatureId<Feature<Gmc>>? = when (geoJson) {
+): FeatureId<Feature<Gmc>> = when (geoJson) {
     is GeoJsonFeature -> geoJsonFeature(geoJson, id = id)
     is GeoJsonFeatureCollection -> group(id = id) {
         geoJson.features.forEach {

maps-kt-geojson/src/jvmMain/kotlin/center/sciprog/maps/geojson/geoJsonFeatureJvm.kt

@@ -1,7 +1,9 @@
 package center.sciprog.maps.geojson
 
 import center.sciprog.maps.coordinates.Gmc
+import center.sciprog.maps.features.Feature
 import center.sciprog.maps.features.FeatureGroup
+import center.sciprog.maps.features.FeatureId
 import kotlinx.serialization.json.Json
 import kotlinx.serialization.json.jsonObject
 import java.net.URL
@@ -12,10 +14,10 @@ import java.net.URL
 public fun FeatureGroup<Gmc>.geoJson(
     geoJsonUrl: URL,
     id: String? = null,
-) {
+): FeatureId<Feature<Gmc>> {
     val jsonString = geoJsonUrl.readText()
     val json = Json.parseToJsonElement(jsonString).jsonObject
     val geoJson = GeoJson(json)
 
-    geoJson(geoJson, id)
+    return geoJson(geoJson, id)
 }