Add separate builders for feature state

build.gradle.kts

@@ -10,7 +10,7 @@ val ktorVersion by extra("2.0.3")
 
 allprojects {
     group = "center.sciprog"
-    version = "0.1.0-dev-5"
+    version = "0.1.0-dev-6"
 }
 
 ksciencePublish{

maps-kt-compose/src/commonMain/kotlin/center/sciprog/maps/compose/MapFeaturesState.kt

@@ -52,16 +52,29 @@ public class MapFeaturesState internal constructor(
             condition(it[key] as T)
         }.keys
     }
-}
+    public companion object{
 
-@Composable
-public fun rememberMapFeatureState(
-    builder: MapFeaturesState.() -> Unit = {},
-): MapFeaturesState = remember(builder) {
-    MapFeaturesState(
-        mutableStateMapOf(),
-        mutableStateMapOf()
-    ).apply(builder)
+        /**
+         * Build, but do not remember map feature state
+         */
+        public fun build(
+            builder: MapFeaturesState.() -> Unit = {},
+        ): MapFeaturesState = MapFeaturesState(
+            mutableStateMapOf(),
+            mutableStateMapOf()
+        ).apply(builder)
+
+        /**
+         * Build and remember map feature state
+         */
+        @Composable
+        public fun remember(
+            builder: MapFeaturesState.() -> Unit = {},
+        ): MapFeaturesState = remember(builder) {
+            build(builder)
+        }
+
+    }
 }
 
 public fun MapFeaturesState.circle(

maps-kt-compose/src/commonMain/kotlin/center/sciprog/maps/compose/MapView.kt

@@ -1,7 +1,9 @@
 package center.sciprog.maps.compose
 
 import androidx.compose.foundation.layout.fillMaxSize
-import androidx.compose.runtime.*
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.key
+import androidx.compose.runtime.remember
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.input.pointer.PointerEvent
 import androidx.compose.ui.input.pointer.isPrimaryPressed
@@ -68,15 +70,16 @@ public data class MapViewConfig(
 public expect fun MapView(
     mapTileProvider: MapTileProvider,
     initialViewPoint: MapViewPoint,
-    features: MapFeaturesState,
+    featuresState: MapFeaturesState,
     config: MapViewConfig = MapViewConfig(),
     modifier: Modifier = Modifier.fillMaxSize(),
 )
 
+internal val defaultCanvasSize = DpSize(512.dp, 512.dp)
 
-internal fun GmcRectangle.computeViewPoint(
+public fun GmcRectangle.computeViewPoint(
     mapTileProvider: MapTileProvider,
-    canvasSize: DpSize,
+    canvasSize: DpSize = defaultCanvasSize,
 ): MapViewPoint {
     val zoom = log2(
         min(
@@ -87,7 +90,33 @@ internal fun GmcRectangle.computeViewPoint(
     return MapViewPoint(center, zoom)
 }
 
-internal val defaultCanvasSize = DpSize(512.dp, 512.dp)
+/**
+ * A builder for a Map with static features.
+ */
+@Composable
+public fun MapView(
+    mapTileProvider: MapTileProvider,
+    initialViewPoint: MapViewPoint? = null,
+    initialRectangle: GmcRectangle? = null,
+    featureMap: Map<FeatureId, MapFeature>,
+    config: MapViewConfig = MapViewConfig(),
+    modifier: Modifier = Modifier.fillMaxSize(),
+) {
+    val featuresState = key(featureMap) {
+        MapFeaturesState.build {
+            featureMap.forEach(::addFeature)
+        }
+    }
+
+    val viewPointOverride: MapViewPoint = remember(initialViewPoint, initialRectangle) {
+        initialViewPoint
+            ?: initialRectangle?.computeViewPoint(mapTileProvider)
+            ?: featureMap.values.computeBoundingBox(1.0)?.computeViewPoint(mapTileProvider)
+            ?: MapViewPoint.globe
+    }
+
+    MapView(mapTileProvider, viewPointOverride, featuresState, config, modifier)
+}
 
 /**
  * Draw a map using convenient parameters. If neither [initialViewPoint], noe [initialRectangle] is defined,
@@ -104,50 +133,40 @@ public fun MapView(
     config: MapViewConfig = MapViewConfig(),
     modifier: Modifier = Modifier.fillMaxSize(),
     buildFeatures: MapFeaturesState.() -> Unit = {},
-): Unit = key(buildFeatures) {
-
-    val featureState = rememberMapFeatureState(buildFeatures)
+) {
+    val featureState = MapFeaturesState.remember(buildFeatures)
 
     val features = featureState.features()
 
     val viewPointOverride: MapViewPoint = remember(initialViewPoint, initialRectangle) {
         initialViewPoint
-            ?: initialRectangle?.computeViewPoint(mapTileProvider, defaultCanvasSize)
-            ?: features.values.computeBoundingBox(1.0)?.computeViewPoint(mapTileProvider, defaultCanvasSize)
+            ?: initialRectangle?.computeViewPoint(mapTileProvider)
+            ?: features.values.computeBoundingBox(1.0)?.computeViewPoint(mapTileProvider)
             ?: MapViewPoint.globe
     }
 
-    val featureDrag by remember {
-        derivedStateOf {
-            DragHandle.withPrimaryButton { _, start, end ->
-                val zoom = start.zoom
-                featureState.findAllWithAttribute(DraggableAttribute) { it }.forEach { id ->
-                    val feature = features[id] as? DraggableMapFeature ?: return@forEach
-                    val boundingBox = feature.getBoundingBox(zoom) ?: return@forEach
-                    if (start.focus in boundingBox) {
-                        featureState.addFeature(id, feature.withCoordinates(end.focus))
-                        return@withPrimaryButton false
-                    }
-                }
-                return@withPrimaryButton true
+    val featureDrag = DragHandle.withPrimaryButton { _, start, end ->
+        val zoom = start.zoom
+        featureState.findAllWithAttribute(DraggableAttribute) { it }.forEach { id ->
+            val feature = features[id] as? DraggableMapFeature ?: return@forEach
+            val boundingBox = feature.getBoundingBox(zoom) ?: return@forEach
+            if (start.focus in boundingBox) {
+                featureState.addFeature(id, feature.withCoordinates(end.focus))
+                return@withPrimaryButton false
             }
         }
+        return@withPrimaryButton true
     }
 
 
-    val newConfig by remember {
-        derivedStateOf {
-            config.copy(
-                dragHandle = DragHandle.combine(featureDrag, config.dragHandle)
-            )
-        }
-    }
-
+    val newConfig = config.copy(
+        dragHandle = DragHandle.combine(featureDrag, config.dragHandle)
+    )
 
     MapView(
         mapTileProvider = mapTileProvider,
         initialViewPoint = viewPointOverride,
-        features = featureState,
+        featuresState = featureState,
         config = newConfig,
         modifier = modifier,
     )

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

@@ -49,7 +49,7 @@ private val logger = KotlinLogging.logger("MapView")
 public actual fun MapView(
     mapTileProvider: MapTileProvider,
     initialViewPoint: MapViewPoint,
-    features: MapFeaturesState,
+    featuresState: MapFeaturesState,
     config: MapViewConfig,
     modifier: Modifier,
 ): Unit = key(initialViewPoint) {
@@ -216,8 +216,8 @@ public actual fun MapView(
         }
     }
 
-    val painterCache = features.features().values.filterIsInstance<MapVectorImageFeature>().associateWith { it.painter() }
-
+    val painterCache = featuresState.features().values.filterIsInstance<MapVectorImageFeature>()
+        .associateWith { it.painter() }
 
     Canvas(canvasModifier) {
         fun WebMercatorCoordinates.toOffset(): Offset = Offset(
@@ -338,10 +338,12 @@ public actual fun MapView(
                     dstSize = tileSize
                 )
             }
-            features.features().values.filter { zoom in it.zoomRange }.forEach { feature ->
+
+            featuresState.features().values.filter { zoom in it.zoomRange }.forEach { feature ->
                 drawFeature(zoom, feature)
             }
         }
+
         selectRect?.let { rect ->
             drawRect(
                 color = Color.Blue,