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

@@ -2,3 +2,5 @@ import kotlin.math.PI
 
 fun Double.toDegrees() = this * 180 / PI
 
+fun Double.toRadians() = this * PI / 180
+

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

@@ -10,9 +10,7 @@ import androidx.compose.ui.graphics.PointMode
 import androidx.compose.ui.window.Window
 import androidx.compose.ui.window.application
 import center.sciprog.maps.compose.*
-import center.sciprog.maps.coordinates.Distance
-import center.sciprog.maps.coordinates.GeodeticMapCoordinates
-import center.sciprog.maps.coordinates.MapViewPoint
+import center.sciprog.maps.coordinates.*
 import io.ktor.client.HttpClient
 import io.ktor.client.engine.cio.CIO
 import kotlinx.coroutines.delay
@@ -52,24 +50,11 @@ fun App() {
         val pointOne = 55.568548 to 37.568604
         var pointTwo by remember { mutableStateOf(55.929444 to 37.518434) }
         val pointThree = 60.929444 to 37.518434
-        MapView(
-            mapTileProvider = mapTileProvider,
-            initialViewPoint = viewPoint,
-            config = MapViewConfig(
-                inferViewBoxFromFeatures = true,
-                onViewChange = { centerCoordinates = focus },
-                onDrag = { start, end ->
-                    if (start.focus.latitude.toDegrees() in (pointTwo.first - 0.05)..(pointTwo.first + 0.05) &&
-                        start.focus.longitude.toDegrees() in (pointTwo.second - 0.05)..(pointTwo.second + 0.05)
-                    ) {
-                        pointTwo = pointTwo.first + (end.focus.latitude - start.focus.latitude).toDegrees() to
-                                pointTwo.second + (end.focus.longitude - start.focus.longitude).toDegrees()
-                        false// returning false, because when we are dragging circle we don't want to drag map
-                    } else true
-                }
-            )
-        ) {
 
+        val state = MapViewState(
+            mapTileProvider = mapTileProvider,
+            initialViewPoint = { viewPoint },
+        ) {
             image(pointOne, Icons.Filled.Home)
 
             points(
@@ -89,7 +74,19 @@ fun App() {
                 centerCoordinates = pointTwo,
             )
 
-            draw(position = pointThree) {
+            draw(
+                position = pointThree,
+                getBoundingBox = {
+                    GmcBox.withCenter(
+                        center = GeodeticMapCoordinates.ofDegrees(
+                            pointThree.first,
+                            pointThree.second
+                        ),
+                        height = Distance(0.001),
+                        width = Distance(0.001)
+                    )
+                }
+            ) {
                 drawLine(start = Offset(-10f, -10f), end = Offset(10f, 10f), color = Color.Red)
                 drawLine(start = Offset(-10f, 10f), end = Offset(10f, -10f), color = Color.Red)
             }
@@ -118,6 +115,29 @@ fun App() {
                 }
             }
         }
+
+        val config = MapViewConfig(
+            onViewChange = { centerCoordinates = focus },
+            onDrag = { start, end ->
+                val markerRadius = 5f
+                val startPosition = with(state) { start.focus.toOffset(this@MapViewConfig) }
+                val markerLocation = with(state) {
+                    GeodeticMapCoordinates.ofDegrees(pointTwo.first, pointTwo.second).toOffset(this@MapViewConfig)
+                }
+                if (startPosition.x in (markerLocation.x - markerRadius)..(markerLocation.x + markerRadius) &&
+                    startPosition.y in (markerLocation.y - markerRadius)..(markerLocation.y + markerRadius)
+                ) {
+                    pointTwo = pointTwo.first + (end.focus.latitude - start.focus.latitude).toDegrees() to
+                            pointTwo.second + (end.focus.longitude - start.focus.longitude).toDegrees()
+                    false// returning false, because when we are dragging circle we don't want to drag map
+                } else true
+            }
+        )
+
+        MapView(
+            mapViewState = state,
+            mapViewConfig = config
+        )
     }
 }
 

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

@@ -41,12 +41,10 @@ public class MapFeatureSelector(
 public class MapDrawFeature(
     public val position: GeodeticMapCoordinates,
     override val zoomRange: IntRange = defaultZoomRange,
+    private val computeBoundingBox: (zoom: Int) -> GmcBox,
     public val drawFeature: DrawScope.() -> Unit,
 ) : MapFeature {
-    override fun getBoundingBox(zoom: Int): GmcBox {
-        //TODO add box computation
-        return GmcBox(position, position)
-    }
+    override fun getBoundingBox(zoom: Int): GmcBox = computeBoundingBox(zoom)
 }
 
 public class MapPointsFeature(

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

@@ -72,8 +72,9 @@ public fun MapFeatureBuilder.draw(
     position: Pair<Double, Double>,
     zoomRange: IntRange = defaultZoomRange,
     id: FeatureId? = null,
+    getBoundingBox: (Int) -> GmcBox,
     drawFeature: DrawScope.() -> Unit,
-): FeatureId = addFeature(id, MapDrawFeature(position.toCoordinates(), zoomRange, drawFeature))
+): FeatureId = addFeature(id, MapDrawFeature(position.toCoordinates(), zoomRange, getBoundingBox, drawFeature))
 
 public fun MapFeatureBuilder.line(
     aCoordinates: Pair<Double, Double>,
@@ -144,3 +145,13 @@ public fun MapFeatureBuilder.group(
     val feature = MapFeatureGroup(map, zoomRange)
     return addFeature(id, feature)
 }
+
+public fun MapFeatureBuilder.featureSelector(
+    id: FeatureId? = null,
+    onSelect: MapFeatureBuilder.(zoom: Int) -> MapFeature
+): FeatureId = addFeature(
+    id = id,
+    feature = MapFeatureSelector(
+        selector = { onSelect(this, it) }
+    )
+)

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

@@ -1,10 +1,15 @@
 package center.sciprog.maps.compose
 
 import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.NativeCanvas
 import center.sciprog.maps.coordinates.GeodeticMapCoordinates
 import center.sciprog.maps.coordinates.GmcBox
-import org.jetbrains.skia.Font
 
+public expect class Font constructor() {
+    public var size: Float
+}
+
+public expect fun NativeCanvas.drawString(text: String, x: Float, y: Float, font: Font, color: Color)
 
 public class MapTextFeature(
     public val position: GeodeticMapCoordinates,

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

@@ -3,6 +3,7 @@ package center.sciprog.maps.compose
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.Density
 import androidx.compose.ui.unit.DpSize
 import center.sciprog.maps.coordinates.*
 import kotlin.math.PI
@@ -17,9 +18,8 @@ import kotlin.math.min
  */
 public data class MapViewConfig(
     val zoomSpeed: Double = 1.0 / 3.0,
-    val inferViewBoxFromFeatures: Boolean = false,
     val onClick: MapViewPoint.() -> Unit = {},
-    val onDrag: (start: MapViewPoint, end: MapViewPoint) -> Boolean = { _, _ -> true },
+    val onDrag: Density.(start: MapViewPoint, end: MapViewPoint) -> Boolean = { _, _ -> true },
     val onViewChange: MapViewPoint.() -> Unit = {},
     val onSelect: (GmcBox) -> Unit = {},
     val zoomOnSelect: Boolean = true,
@@ -28,11 +28,9 @@ public data class MapViewConfig(
 
 @Composable
 public expect fun MapView(
-    mapTileProvider: MapTileProvider,
-    computeViewPoint: (canvasSize: DpSize) -> MapViewPoint,
-    features: Map<FeatureId, MapFeature>,
-    config: MapViewConfig = MapViewConfig(),
-    modifier: Modifier = Modifier.fillMaxSize(),
+    modifier: Modifier = Modifier,
+    mapViewState: MapViewState,
+    mapViewConfig: MapViewConfig,
 )
 
 @Composable
@@ -47,23 +45,26 @@ public fun MapView(
     val featuresBuilder = MapFeatureBuilderImpl(features)
     featuresBuilder.buildFeatures()
     MapView(
-        mapTileProvider,
-        { initialViewPoint },
-        featuresBuilder.build(),
-        config,
-        modifier
+        mapViewState = MapViewState(
+            mapTileProvider = mapTileProvider,
+            initialViewPoint = { initialViewPoint },
+            features = featuresBuilder.build(),
+        ),
+        mapViewConfig = config,
+        modifier = modifier
     )
 }
 
-internal fun GmcBox.computeViewPoint(mapTileProvider: MapTileProvider): (canvasSize: DpSize) -> MapViewPoint = { canvasSize ->
-    val zoom = log2(
-        min(
-            canvasSize.width.value / width,
-            canvasSize.height.value / height
-        ) * PI / mapTileProvider.tileSize
-    )
-    MapViewPoint(center, zoom)
-}
+internal fun GmcBox.computeViewPoint(mapTileProvider: MapTileProvider): (canvasSize: DpSize) -> MapViewPoint =
+    { canvasSize ->
+        val zoom = log2(
+            min(
+                canvasSize.width.value / width,
+                canvasSize.height.value / height
+            ) * PI / mapTileProvider.tileSize
+        )
+        MapViewPoint(center, zoom)
+    }
 
 @Composable
 public fun MapView(
@@ -77,10 +78,12 @@ public fun MapView(
     val featuresBuilder = MapFeatureBuilderImpl(features)
     featuresBuilder.buildFeatures()
     MapView(
-        mapTileProvider,
-        box.computeViewPoint(mapTileProvider),
-        featuresBuilder.build(),
-        config,
-        modifier
+        mapViewState = MapViewState(
+            mapTileProvider = mapTileProvider,
+            features = featuresBuilder.build(),
+            initialViewPoint = box.computeViewPoint(mapTileProvider),
+        ),
+        modifier = modifier,
+        mapViewConfig = config,
     )
 }

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

@@ -0,0 +1,181 @@
+package center.sciprog.maps.compose
+
+import androidx.compose.runtime.*
+import androidx.compose.runtime.snapshots.SnapshotStateList
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.geometry.Rect
+import androidx.compose.ui.graphics.Path
+import androidx.compose.ui.graphics.drawscope.DrawScope
+import androidx.compose.ui.graphics.drawscope.Stroke
+import androidx.compose.ui.graphics.drawscope.drawIntoCanvas
+import androidx.compose.ui.graphics.drawscope.translate
+import androidx.compose.ui.graphics.nativeCanvas
+import androidx.compose.ui.unit.Density
+import androidx.compose.ui.unit.DpOffset
+import androidx.compose.ui.unit.DpSize
+import androidx.compose.ui.unit.dp
+import center.sciprog.maps.coordinates.*
+import mu.KotlinLogging
+import kotlin.math.*
+
+@Composable
+public fun MapViewState(
+    initialViewPoint: (canvasSize: DpSize) -> MapViewPoint,
+    mapTileProvider: MapTileProvider,
+    features: Map<FeatureId, MapFeature> = emptyMap(),
+    inferViewBoxFromFeatures: Boolean = false,
+    buildFeatures: @Composable (MapFeatureBuilder.() -> Unit) = {},
+): MapViewState {
+    val featuresBuilder = MapFeatureBuilderImpl(features)
+    featuresBuilder.buildFeatures()
+    return MapViewState(
+        initialViewPoint = initialViewPoint,
+        mapTileProvider = mapTileProvider,
+        features = featuresBuilder.build(),
+        inferViewBoxFromFeatures = inferViewBoxFromFeatures
+    )
+}
+
+public class MapViewState(
+    public val initialViewPoint: (canvasSize: DpSize) -> MapViewPoint,
+    public val mapTileProvider: MapTileProvider,
+    public val features: Map<FeatureId, MapFeature> = emptyMap(),
+    inferViewBoxFromFeatures: Boolean = false,
+) {
+    public var canvasSize: DpSize by mutableStateOf(DpSize(512.dp, 512.dp))
+    public var viewPointInternal: MapViewPoint? by mutableStateOf(null)
+    public val viewPoint: MapViewPoint by derivedStateOf {
+        viewPointInternal ?: if (inferViewBoxFromFeatures) {
+            features.values.computeBoundingBox(1)?.let { box ->
+                val zoom = log2(
+                    min(
+                        canvasSize.width.value / box.width,
+                        canvasSize.height.value / box.height
+                    ) * PI / mapTileProvider.tileSize
+                )
+                MapViewPoint(box.center, zoom)
+            } ?: initialViewPoint(canvasSize)
+        } else {
+            initialViewPoint(canvasSize)
+        }
+    }
+    public val zoom: Int by derivedStateOf { floor(viewPoint.zoom).toInt() }
+
+    public val tileScale: Double by derivedStateOf { 2.0.pow(viewPoint.zoom - zoom) }
+
+    public val mapTiles: SnapshotStateList<MapTile> = mutableStateListOf()
+
+    public val centerCoordinates: WebMercatorCoordinates by derivedStateOf {
+        WebMercatorProjection.toMercator(
+            viewPoint.focus,
+            zoom
+        )
+    }
+
+    public fun DpOffset.toMercator(): WebMercatorCoordinates = WebMercatorCoordinates(
+        zoom,
+        (x - canvasSize.width / 2).value / tileScale + centerCoordinates.x,
+        (y - canvasSize.height / 2).value / tileScale + centerCoordinates.y,
+    )
+
+    /*
+     * Convert screen independent offset to GMC, adjusting for fractional zoom
+     */
+    public fun DpOffset.toGeodetic(): GeodeticMapCoordinates =
+        with(this@MapViewState) { WebMercatorProjection.toGeodetic(toMercator()) }
+
+    // Selection rectangle. If null - no selection
+    public var selectRect: Rect? by mutableStateOf(null)
+
+    public fun WebMercatorCoordinates.toOffset(density: Density): Offset =
+        with(density) {
+            with(this@MapViewState) {
+                Offset(
+                    (canvasSize.width / 2 + (x.dp - centerCoordinates.x.dp) * tileScale.toFloat()).toPx(),
+                    (canvasSize.height / 2 + (y.dp - centerCoordinates.y.dp) * tileScale.toFloat()).toPx()
+                )
+            }
+        }
+
+    //Convert GMC to offset in pixels (not DP), adjusting for zoom
+    public fun GeodeticMapCoordinates.toOffset(density: Density): Offset =
+        WebMercatorProjection.toMercator(this, zoom).toOffset(density)
+
+    private val logger = KotlinLogging.logger("MapViewState")
+
+    public fun DrawScope.drawFeature(zoom: Int, feature: MapFeature) {
+        when (feature) {
+            is MapFeatureSelector -> drawFeature(zoom, feature.selector(zoom))
+            is MapCircleFeature -> drawCircle(
+                feature.color,
+                feature.size,
+                center = feature.center.toOffset(this@drawFeature)
+            )
+            is MapRectangleFeature -> drawRect(
+                feature.color,
+                topLeft = feature.center.toOffset(this@drawFeature) - Offset(
+                    feature.size.width.toPx() / 2,
+                    feature.size.height.toPx() / 2
+                ),
+                size = feature.size.toSize()
+            )
+            is MapLineFeature -> drawLine(
+                feature.color,
+                feature.a.toOffset(this@drawFeature),
+                feature.b.toOffset(this@drawFeature)
+            )
+            is MapArcFeature -> {
+                val topLeft = feature.oval.topLeft.toOffset(this@drawFeature)
+                val bottomRight = feature.oval.bottomRight.toOffset(this@drawFeature)
+
+                val path = Path().apply {
+                    addArcRad(Rect(topLeft, bottomRight), feature.startAngle, feature.endAngle - feature.startAngle)
+                }
+
+                drawPath(path, color = feature.color, style = Stroke())
+
+            }
+            is MapBitmapImageFeature -> drawImage(
+                image = feature.image,
+                topLeft = feature.position.toOffset(this@drawFeature)
+            )
+            is MapVectorImageFeature -> {
+                val offset = feature.position.toOffset(this@drawFeature)
+                val size = feature.size.toSize()
+                translate(offset.x - size.width / 2, offset.y - size.height / 2) {
+                    with(feature.painter) {
+                        draw(size)
+                    }
+                }
+            }
+            is MapTextFeature -> drawIntoCanvas { canvas ->
+                val offset = feature.position.toOffset(this@drawFeature)
+                canvas.nativeCanvas.drawString(
+                    feature.text,
+                    offset.x + 5,
+                    offset.y - 5,
+                    Font().apply(feature.fontConfig),
+                    feature.color
+                )
+            }
+            is MapDrawFeature -> {
+                val offset = feature.position.toOffset(this)
+                translate(offset.x, offset.y) {
+                    feature.drawFeature(this)
+                }
+            }
+            is MapFeatureGroup -> {
+                feature.children.values.forEach {
+                    drawFeature(zoom, it)
+                }
+            }
+            else -> {
+                logger.error { "Unrecognized feature type: ${feature::class}" }
+            }
+        }
+    }
+}
+
+
+
+

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

@@ -0,0 +1,23 @@
+package center.sciprog.maps.compose
+
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.NativeCanvas
+import androidx.compose.ui.graphics.toArgb
+import org.jetbrains.skia.Paint
+
+public actual typealias Font = org.jetbrains.skia.Font
+
+public actual fun NativeCanvas.drawString(
+    text: String,
+    x: Float,
+    y: Float,
+    font: Font,
+    color: Color
+) {
+    drawString(text, x, y, font, color.toPaint())
+}
+
+private fun Color.toPaint(): Paint = Paint().apply {
+    isAntiAlias = true
+    color = toArgb()
+}

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

@@ -17,15 +17,10 @@ import center.sciprog.maps.coordinates.*
 import kotlinx.coroutines.CancellationException
 import kotlinx.coroutines.launch
 import mu.KotlinLogging
-import org.jetbrains.skia.Font
-import org.jetbrains.skia.Paint
 import kotlin.math.*
 
 
-private fun Color.toPaint(): Paint = Paint().apply {
-    isAntiAlias = true
-    color = toArgb()
-}
+
 
 private fun IntRange.intersect(other: IntRange) = max(first, other.first)..min(last, other.last)
 
@@ -48,292 +43,171 @@ private val logger = KotlinLogging.logger("MapView")
 
 @Composable
 public actual fun MapView(
-    mapTileProvider: MapTileProvider,
-    computeViewPoint: (canvasSize: DpSize) -> MapViewPoint,
-    features: Map<FeatureId, MapFeature>,
-    config: MapViewConfig,
     modifier: Modifier,
+    mapViewState: MapViewState,
+    mapViewConfig: MapViewConfig,
 ) {
-    var canvasSize by remember { mutableStateOf(DpSize(512.dp, 512.dp)) }
+    with(mapViewState) {
+        @OptIn(ExperimentalComposeUiApi::class)
+        val canvasModifier = modifier.pointerInput(Unit) {
+            forEachGesture {
+                awaitPointerEventScope {
+                    fun Offset.toDpOffset() = DpOffset(x.toDp(), y.toDp())
 
-    var viewPointInternal: MapViewPoint? by remember {
-        mutableStateOf(null)
-    }
-
-    if (config.resetViewPoint) {
-        viewPointInternal = null
-    }
-
-    val viewPoint: MapViewPoint by derivedStateOf {
-        viewPointInternal ?: if (config.inferViewBoxFromFeatures) {
-            features.values.computeBoundingBox(1)?.let { box ->
-                val zoom = log2(
-                    min(
-                        canvasSize.width.value / box.width,
-                        canvasSize.height.value / box.height
-                    ) * PI / mapTileProvider.tileSize
-                )
-                MapViewPoint(box.center, zoom)
-            } ?: computeViewPoint(canvasSize)
-        } else {
-            computeViewPoint(canvasSize)
-        }
-    }
-
-    val zoom: Int by derivedStateOf { floor(viewPoint.zoom).toInt() }
-
-    val tileScale: Double by derivedStateOf { 2.0.pow(viewPoint.zoom - zoom) }
-
-    val mapTiles = remember { mutableStateListOf<MapTile>() }
-
-    val centerCoordinates by derivedStateOf { WebMercatorProjection.toMercator(viewPoint.focus, zoom) }
-
-    fun DpOffset.toMercator(): WebMercatorCoordinates = WebMercatorCoordinates(
-        zoom,
-        (x - canvasSize.width / 2).value / tileScale + centerCoordinates.x,
-        (y - canvasSize.height / 2).value / tileScale + centerCoordinates.y,
-    )
-
-    /*
-     * Convert screen independent offset to GMC, adjusting for fractional zoom
-     */
-    fun DpOffset.toGeodetic() = WebMercatorProjection.toGeodetic(toMercator())
-
-    // Selection rectangle. If null - no selection
-    var selectRect by remember { mutableStateOf<Rect?>(null) }
-
-    @OptIn(ExperimentalComposeUiApi::class)
-    val canvasModifier = modifier.pointerInput(Unit) {
-        forEachGesture {
-            awaitPointerEventScope {
-                fun Offset.toDpOffset() = DpOffset(x.toDp(), y.toDp())
-
-                val event: PointerEvent = awaitPointerEvent()
-                event.changes.forEach { change ->
-                    if (event.buttons.isPrimaryPressed) {
-                        //Evaluating selection frame
-                        if (event.keyboardModifiers.isShiftPressed) {
-                            selectRect = Rect(change.position, change.position)
-                            drag(change.id) { dragChange ->
-                                selectRect?.let { rect ->
-                                    val offset = dragChange.position
-                                    selectRect = Rect(
-                                        min(offset.x, rect.left),
-                                        min(offset.y, rect.top),
-                                        max(offset.x, rect.right),
-                                        max(offset.y, rect.bottom)
-                                    )
+                    val event: PointerEvent = awaitPointerEvent()
+                    event.changes.forEach { change ->
+                        if (event.buttons.isPrimaryPressed) {
+                            //Evaluating selection frame
+                            if (event.keyboardModifiers.isShiftPressed) {
+                                selectRect = Rect(change.position, change.position)
+                                drag(change.id) { dragChange ->
+                                    selectRect?.let { rect ->
+                                        val offset = dragChange.position
+                                        selectRect = Rect(
+                                            min(offset.x, rect.left),
+                                            min(offset.y, rect.top),
+                                            max(offset.x, rect.right),
+                                            max(offset.y, rect.bottom)
+                                        )
+                                    }
                                 }
-                            }
-                            selectRect?.let { rect ->
-                                //Use selection override if it is defined
-                                val gmcBox = GmcBox(
-                                    rect.topLeft.toDpOffset().toGeodetic(),
-                                    rect.bottomRight.toDpOffset().toGeodetic()
-                                )
-                                config.onSelect(gmcBox)
-                                if (config.zoomOnSelect) {
-                                    val newViewPoint = gmcBox.computeViewPoint(mapTileProvider).invoke(canvasSize)
+                                selectRect?.let { rect ->
+                                    //Use selection override if it is defined
+                                    val gmcBox = GmcBox(
+                                            rect.topLeft.toDpOffset().toGeodetic(),
+                                            rect.bottomRight.toDpOffset().toGeodetic()
+                                        )
 
-                                    config.onViewChange(newViewPoint)
+                                    mapViewConfig.onSelect(gmcBox)
+                                    if (mapViewConfig.zoomOnSelect) {
+                                        val newViewPoint = gmcBox.computeViewPoint(mapTileProvider).invoke(canvasSize)
+
+                                        mapViewConfig.onViewChange(newViewPoint)
+                                        viewPointInternal = newViewPoint
+                                    }
+                                    selectRect = null
+                                }
+                            } else {
+                                val dragStart = change.position
+                                val dpPos = DpOffset(dragStart.x.toDp(), dragStart.y.toDp())
+                                mapViewConfig.onClick(
+                                    MapViewPoint(
+                                         dpPos.toGeodetic() ,
+                                        viewPoint.zoom
+                                    )
+                                )
+                                drag(change.id) { dragChange ->
+                                    val dragAmount = dragChange.position - dragChange.previousPosition
+                                    val dpStart =
+                                        DpOffset(
+                                            dragChange.previousPosition.x.toDp(),
+                                            dragChange.previousPosition.y.toDp()
+                                        )
+                                    val dpEnd = DpOffset(dragChange.position.x.toDp(), dragChange.position.y.toDp())
+                                    if (!mapViewConfig.onDrag(
+                                            this,
+                                            MapViewPoint(dpStart.toGeodetic(), viewPoint.zoom),
+                                            MapViewPoint(dpEnd.toGeodetic(), viewPoint.zoom)
+                                        )
+                                    ) return@drag
+                                    val newViewPoint = viewPoint.move(
+                                        -dragAmount.x.toDp().value / tileScale,
+                                        +dragAmount.y.toDp().value / tileScale
+                                    )
+                                    mapViewConfig.onViewChange(newViewPoint)
                                     viewPointInternal = newViewPoint
                                 }
-                                selectRect = null
                             }
-                        } else {
-                            val dragStart = change.position
-                            val dpPos = DpOffset(dragStart.x.toDp(), dragStart.y.toDp())
-                            config.onClick(MapViewPoint(dpPos.toGeodetic(), viewPoint.zoom))
-                            drag(change.id) { dragChange ->
-                                val dragAmount = dragChange.position - dragChange.previousPosition
-                                val dpStart =
-                                    DpOffset(dragChange.previousPosition.x.toDp(), dragChange.previousPosition.y.toDp())
-                                val dpEnd = DpOffset(dragChange.position.x.toDp(), dragChange.position.y.toDp())
-                                if (!config.onDrag(
-                                        MapViewPoint(dpStart.toGeodetic(), viewPoint.zoom),
-                                        MapViewPoint(dpEnd.toGeodetic(), viewPoint.zoom)
-                                    )
-                                ) return@drag
-                                val newViewPoint = viewPoint.move(
-                                    -dragAmount.x.toDp().value / tileScale,
-                                    +dragAmount.y.toDp().value / tileScale
-                                )
-                                config.onViewChange(newViewPoint)
-                                viewPointInternal = newViewPoint
+                        }
+                    }
+                }
+            }
+        }.onPointerEvent(PointerEventType.Scroll) {
+            val change = it.changes.first()
+            val (xPos, yPos) = change.position
+            //compute invariant point of translation
+            val invariant = DpOffset(xPos.toDp(), yPos.toDp()).toGeodetic()
+            val newViewPoint = viewPoint.zoom(-change.scrollDelta.y.toDouble() * mapViewConfig.zoomSpeed, invariant)
+            mapViewConfig.onViewChange(newViewPoint)
+            viewPointInternal = newViewPoint
+        }.fillMaxSize()
+
+
+        // Load tiles asynchronously
+        LaunchedEffect(viewPoint, canvasSize) {
+            with(mapTileProvider) {
+                val indexRange = 0 until 2.0.pow(zoom).toInt()
+
+                val left = centerCoordinates.x - canvasSize.width.value / 2 / tileScale
+                val right = centerCoordinates.x + canvasSize.width.value / 2 / tileScale
+                val horizontalIndices: IntRange = (toIndex(left)..toIndex(right)).intersect(indexRange)
+
+                val top = (centerCoordinates.y + canvasSize.height.value / 2 / tileScale)
+                val bottom = (centerCoordinates.y - canvasSize.height.value / 2 / tileScale)
+                val verticalIndices: IntRange = (toIndex(bottom)..toIndex(top)).intersect(indexRange)
+
+                mapTiles.clear()
+
+                for (j in verticalIndices) {
+                    for (i in horizontalIndices) {
+                        val id = TileId(zoom, i, j)
+                        //start all
+                        val deferred = loadTileAsync(id)
+                        //wait asynchronously for it to finish
+                        launch {
+                            try {
+                                mapTiles += deferred.await()
+                            } catch (ex: Exception) {
+                                if (ex !is CancellationException) {
+                                    //displaying the error is maps responsibility
+                                    logger.error(ex) { "Failed to load tile with id=$id" }
+                                }
                             }
                         }
                     }
                 }
             }
         }
-    }.onPointerEvent(PointerEventType.Scroll) {
-        val change = it.changes.first()
-        val (xPos, yPos) = change.position
-        //compute invariant point of translation
-        val invariant = DpOffset(xPos.toDp(), yPos.toDp()).toGeodetic()
-        val newViewPoint = viewPoint.zoom(-change.scrollDelta.y.toDouble() * config.zoomSpeed, invariant)
-        config.onViewChange(newViewPoint)
-        viewPointInternal = newViewPoint
-    }.fillMaxSize()
 
 
-    // Load tiles asynchronously
-    LaunchedEffect(viewPoint, canvasSize) {
-        with(mapTileProvider) {
-            val indexRange = 0 until 2.0.pow(zoom).toInt()
-
-            val left = centerCoordinates.x - canvasSize.width.value / 2 / tileScale
-            val right = centerCoordinates.x + canvasSize.width.value / 2 / tileScale
-            val horizontalIndices: IntRange = (toIndex(left)..toIndex(right)).intersect(indexRange)
-
-            val top = (centerCoordinates.y + canvasSize.height.value / 2 / tileScale)
-            val bottom = (centerCoordinates.y - canvasSize.height.value / 2 / tileScale)
-            val verticalIndices: IntRange = (toIndex(bottom)..toIndex(top)).intersect(indexRange)
-
-            mapTiles.clear()
-
-            for (j in verticalIndices) {
-                for (i in horizontalIndices) {
-                    val id = TileId(zoom, i, j)
-                    //start all
-                    val deferred = loadTileAsync(id)
-                    //wait asynchronously for it to finish
-                    launch {
-                        try {
-                            mapTiles += deferred.await()
-                        } catch (ex: Exception) {
-                            if (ex !is CancellationException) {
-                                //displaying the error is maps responsibility
-                                logger.error(ex) { "Failed to load tile with id=$id" }
-                            }
-                        }
-                    }
-                }
+        Canvas(canvasModifier) {
+        if (mapViewState.canvasSize != size.toDpSize()) {
+            mapViewState.canvasSize = size.toDpSize()
+                logger.debug { "Recalculate canvas. Size: $size" }
             }
-        }
-    }
-
-
-    Canvas(canvasModifier) {
-        fun WebMercatorCoordinates.toOffset(): Offset = Offset(
-            (canvasSize.width / 2 + (x.dp - centerCoordinates.x.dp) * tileScale.toFloat()).toPx(),
-            (canvasSize.height / 2 + (y.dp - centerCoordinates.y.dp) * tileScale.toFloat()).toPx()
-        )
-
-        //Convert GMC to offset in pixels (not DP), adjusting for zoom
-        fun GeodeticMapCoordinates.toOffset(): Offset = WebMercatorProjection.toMercator(this, zoom).toOffset()
-
-
-        fun DrawScope.drawFeature(zoom: Int, feature: MapFeature) {
-            when (feature) {
-                is MapFeatureSelector -> drawFeature(zoom, feature.selector(zoom))
-                is MapCircleFeature -> drawCircle(
-                    feature.color,
-                    feature.size,
-                    center = feature.center.toOffset()
+            clipRect {
+                val tileSize = IntSize(
+                    ceil((mapTileProvider.tileSize.dp * tileScale.toFloat()).toPx()).toInt(),
+                    ceil((mapTileProvider.tileSize.dp * tileScale.toFloat()).toPx()).toInt()
                 )
-                is MapRectangleFeature -> drawRect(
-                    feature.color,
-                    topLeft = feature.center.toOffset() - Offset(
-                        feature.size.width.toPx() / 2,
-                        feature.size.height.toPx() / 2
-                    ),
-                    size = feature.size.toSize()
-                )
-                is MapLineFeature -> drawLine(feature.color, feature.a.toOffset(), feature.b.toOffset())
-                is MapArcFeature -> {
-                    val topLeft = feature.oval.topLeft.toOffset()
-                    val bottomRight = feature.oval.bottomRight.toOffset()
-
-                    val path = Path().apply {
-                        addArcRad(Rect(topLeft, bottomRight), feature.startAngle, feature.endAngle - feature.startAngle)
-                    }
-
-                    drawPath(path, color = feature.color, style = Stroke())
-
-                }
-                is MapBitmapImageFeature -> drawImage(feature.image, feature.position.toOffset())
-                is MapVectorImageFeature -> {
-                    val offset = feature.position.toOffset()
-                    val size = feature.size.toSize()
-                    translate(offset.x - size.width / 2, offset.y - size.height / 2) {
-                        with(feature.painter) {
-                            draw(size)
-                        }
-                    }
-                }
-                is MapTextFeature -> drawIntoCanvas { canvas ->
-                    val offset = feature.position.toOffset()
-                    canvas.nativeCanvas.drawString(
-                        feature.text,
-                        offset.x + 5,
-                        offset.y - 5,
-                        Font().apply(feature.fontConfig),
-                        feature.color.toPaint()
+                mapTiles.forEach { (id, image) ->
+                    //converting back from tile index to screen offset
+                    val offset = IntOffset(
+                        (canvasSize.width / 2 + (mapTileProvider.toCoordinate(id.i).dp - centerCoordinates.x.dp) * tileScale.toFloat()).roundToPx(),
+                        (canvasSize.height / 2 + (mapTileProvider.toCoordinate(id.j).dp - centerCoordinates.y.dp) * tileScale.toFloat()).roundToPx()
+                    )
+                    drawImage(
+                        image = image,
+                        dstOffset = offset,
+                        dstSize = tileSize
                     )
                 }
-                is MapDrawFeature -> {
-                    val offset = feature.position.toOffset()
-                    translate(offset.x, offset.y) {
-                        feature.drawFeature(this)
-                    }
+                features.values.filter { zoom in it.zoomRange }.forEach { feature ->
+                    drawFeature(zoom, feature)
                 }
-                is MapFeatureGroup -> {
-                    feature.children.values.forEach {
-                        drawFeature(zoom, it)
-                    }
-                }
-                is MapPointsFeature -> {
-                    val points = feature.points.map { it.toOffset() }
-                    drawPoints(
-                        points = points,
-                        color = feature.color,
-                        strokeWidth = feature.stroke,
-                        pointMode = feature.pointMode
+            }
+            selectRect?.let { rect ->
+                drawRect(
+                    color = Color.Blue,
+                    topLeft = rect.topLeft,
+                    size = rect.size,
+                    alpha = 0.5f,
+                    style = Stroke(
+                        width = 2f,
+                        pathEffect = PathEffect.dashPathEffect(floatArrayOf(10f, 10f), 0f)
                     )
-                }
-                else -> {
-                    logger.error { "Unrecognized feature type: ${feature::class}" }
-                }
-            }
-        }
-
-        if (canvasSize != size.toDpSize()) {
-            canvasSize = size.toDpSize()
-            logger.debug { "Recalculate canvas. Size: $size" }
-        }
-        clipRect {
-            val tileSize = IntSize(
-                ceil((mapTileProvider.tileSize.dp * tileScale.toFloat()).toPx()).toInt(),
-                ceil((mapTileProvider.tileSize.dp * tileScale.toFloat()).toPx()).toInt()
-            )
-            mapTiles.forEach { (id, image) ->
-                //converting back from tile index to screen offset
-                val offset = IntOffset(
-                    (canvasSize.width / 2 + (mapTileProvider.toCoordinate(id.i).dp - centerCoordinates.x.dp) * tileScale.toFloat()).roundToPx(),
-                    (canvasSize.height / 2 + (mapTileProvider.toCoordinate(id.j).dp - centerCoordinates.y.dp) * tileScale.toFloat()).roundToPx()
-                )
-                drawImage(
-                    image = image,
-                    dstOffset = offset,
-                    dstSize = tileSize
                 )
             }
-            features.values.filter { zoom in it.zoomRange }.forEach { feature ->
-                drawFeature(zoom, feature)
-            }
-        }
-        selectRect?.let { rect ->
-            drawRect(
-                color = Color.Blue,
-                topLeft = rect.topLeft,
-                size = rect.size,
-                alpha = 0.5f,
-                style = Stroke(
-                    width = 2f,
-                    pathEffect = PathEffect.dashPathEffect(floatArrayOf(10f, 10f), 0f)
-                )
-            )
         }
     }
 }