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

@@ -0,0 +1,4 @@
+import kotlin.math.PI
+
+fun Double.toDegrees() = this * 180 / PI
+

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

@@ -7,6 +7,7 @@ import androidx.compose.runtime.*
 import androidx.compose.ui.geometry.Offset
 import androidx.compose.ui.geometry.Size
 import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.PointMode
 import androidx.compose.ui.window.Window
 import androidx.compose.ui.window.application
 import center.sciprog.maps.compose.*
@@ -49,41 +50,42 @@ fun App() {
 
         var centerCoordinates by remember { mutableStateOf<GeodeticMapCoordinates?>(null) }
 
-//        val markers = (1..1_000_000).map {
+
-//            val position = GeodeticMapCoordinates.ofDegrees(
+        val pointOne = 55.568548 to 37.568604
-//                latitude = Random.nextDouble(-90.0, 90.0),
+        var pointTwo by remember { mutableStateOf(55.929444 to 37.518434) }
-//                longitude = Random.nextDouble(0.0, 180.0)
+        val pointThree = 60.929444 to 37.518434
-//            )
-//            MapDrawFeature(
-//                position = position,
-//                computeBoundingBox = {
-//                    GmcBox.withCenter(
-//                        center = position,
-//                        width = Distance(0.001),
-//                        height = Distance(0.001)
-//                    )
-//                }
-//            ) {
-//                drawRoundRect(
-//                    color = Color.Yellow,
-//                    size = Size(1f, 1f)
-//                )
-//            }
-//        }
         val state = MapViewState(
             mapTileProvider = mapTileProvider,
-            computeViewPoint = { viewPoint },
+            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 pointOne = 55.568548 to 37.568604
-            val pointTwo = 55.929444 to 37.518434
-            val pointThree = 60.929444 to 37.518434
 
             image(pointOne, Icons.Filled.Home)
 
+            points(
+                points = listOf(
+                    55.742465 to 37.615812,
+                    55.742713 to 37.616370,
+                    55.742815 to 37.616659,
+                    55.742320 to 37.617132,
+                    55.742086 to 37.616566,
+                    55.741715 to 37.616716
+                ),
+                pointMode = PointMode.Polygon
+            )
+
             //remember feature Id
             val circleId: FeatureId = circle(
                 centerCoordinates = pointTwo,
@@ -106,15 +108,9 @@ fun App() {
                 drawLine(start = Offset(-10f, 10f), end = Offset(10f, -10f), color = Color.Red)
             }
 
-//            markers.forEach { feature ->
-//                featureSelector {
-//                    feature
-//                }
-//            }
-
             arc(pointOne, Distance(10.0), 0f, PI)
 
-            line(pointOne, pointTwo)
+            line(pointOne, pointTwo, id = "line")
             text(pointOne, "Home", font = { size = 32f })
 
             centerCoordinates?.let {

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

@@ -3,6 +3,7 @@ package center.sciprog.maps.compose
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.ImageBitmap
+import androidx.compose.ui.graphics.PointMode
 import androidx.compose.ui.graphics.drawscope.DrawScope
 import androidx.compose.ui.graphics.painter.Painter
 import androidx.compose.ui.graphics.vector.ImageVector
@@ -46,6 +47,18 @@ public class MapDrawFeature(
     override fun getBoundingBox(zoom: Int): GmcBox = computeBoundingBox(zoom)
 }
 
+public class MapPointsFeature(
+    public val points: List<GeodeticMapCoordinates>,
+    override val zoomRange: IntRange = defaultZoomRange,
+    public val stroke: Float = 2f,
+    public val color: Color = Color.Red,
+    public val pointMode: PointMode = PointMode.Points
+) : MapFeature {
+    override fun getBoundingBox(zoom: Int): GmcBox {
+        return GmcBox(points.first(), points.last())
+    }
+}
+
 public class MapCircleFeature(
     public val center: GeodeticMapCoordinates,
     override val zoomRange: IntRange = defaultZoomRange,

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

@@ -4,6 +4,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.runtime.mutableStateMapOf
 import androidx.compose.runtime.snapshots.SnapshotStateMap
 import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.PointMode
 import androidx.compose.ui.graphics.drawscope.DrawScope
 import androidx.compose.ui.graphics.vector.ImageVector
 import androidx.compose.ui.unit.DpSize
@@ -117,6 +118,15 @@ public fun MapFeatureBuilder.arc(
     )
 )
 
+public fun MapFeatureBuilder.points(
+    points: List<Pair<Double, Double>>,
+    zoomRange: IntRange = defaultZoomRange,
+    stroke: Float = 2f,
+    color: Color = Color.Red,
+    pointMode: PointMode = PointMode.Points,
+    id: FeatureId? = null
+): FeatureId = addFeature(id, MapPointsFeature(points.map { it.toCoordinates() }, zoomRange, stroke, color, pointMode))
+
 @Composable
 public fun MapFeatureBuilder.image(
     position: Pair<Double, Double>,

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

@@ -11,10 +11,15 @@ import kotlin.math.min
 
 
 //TODO consider replacing by modifier
+/**
+ * @param onDrag - returns true if you want to drag a map and false, if you want to make map stationary.
+ *          start - is a point where drag begins, end is a point where drag ends
+ */
 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 onViewChange: MapViewPoint.() -> Unit = {},
     val onSelect: (GmcBox) -> Unit = {},
     val zoomOnSelect: Boolean = true,

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

@@ -51,160 +51,166 @@ public actual fun MapView(
     mapViewState: MapViewState,
     modifier: Modifier,
 ) {
-    @OptIn(ExperimentalComposeUiApi::class)
+    with(mapViewState) {
-    val canvasModifier = modifier.pointerInput(Unit) {
+        @OptIn(ExperimentalComposeUiApi::class)
-        forEachGesture {
+        val canvasModifier = modifier.pointerInput(Unit) {
-            awaitPointerEventScope {
+            forEachGesture {
-                fun Offset.toDpOffset() = DpOffset(x.toDp(), y.toDp())
+                awaitPointerEventScope {
+                    fun Offset.toDpOffset() = DpOffset(x.toDp(), y.toDp())
 
-                val event: PointerEvent = awaitPointerEvent()
+                    val event: PointerEvent = awaitPointerEvent()
-                event.changes.forEach { change ->
+                    event.changes.forEach { change ->
-                    if (event.buttons.isPrimaryPressed) {
+                        if (event.buttons.isPrimaryPressed) {
-                        //Evaluating selection frame
+                            //Evaluating selection frame
-                        if (event.keyboardModifiers.isShiftPressed) {
+                            if (event.keyboardModifiers.isShiftPressed) {
-                            mapViewState.selectRect = Rect(change.position, change.position)
+                                selectRect = Rect(change.position, change.position)
-                            drag(change.id) { dragChange ->
+                                drag(change.id) { dragChange ->
-                                mapViewState.selectRect?.let { rect ->
+                                    selectRect?.let { rect ->
-                                    val offset = dragChange.position
+                                        val offset = dragChange.position
-                                    mapViewState.selectRect = Rect(
+                                        selectRect = Rect(
-                                        min(offset.x, rect.left),
+                                            min(offset.x, rect.left),
-                                        min(offset.y, rect.top),
+                                            min(offset.y, rect.top),
-                                        max(offset.x, rect.right),
+                                            max(offset.x, rect.right),
-                                        max(offset.y, rect.bottom)
+                                            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)
+
+                                        config.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
                                 }
                             }
-                            mapViewState.selectRect?.let { rect ->
+                        }
-                                //Use selection override if it is defined
+                    }
-                                val gmcBox = with(mapViewState) {
+                }
-                                    GmcBox(
+            }
-                                        rect.topLeft.toDpOffset().toGeodetic(),
+        }.onPointerEvent(PointerEventType.Scroll) {
-                                        rect.bottomRight.toDpOffset().toGeodetic()
+            val change = it.changes.first()
-                                    )
+            val (xPos, yPos) = change.position
-                                }
+            //compute invariant point of translation
-                                mapViewState.config.onSelect(gmcBox)
+            val invariant = DpOffset(xPos.toDp(), yPos.toDp()).toGeodetic()
-                                if (mapViewState.config.zoomOnSelect) {
+            val newViewPoint = viewPoint.zoom(-change.scrollDelta.y.toDouble() * config.zoomSpeed, invariant)
-                                    val newViewPoint = gmcBox.computeViewPoint(mapViewState.mapTileProvider)
+            config.onViewChange(newViewPoint)
-                                        .invoke(mapViewState.canvasSize)
+            viewPointInternal = newViewPoint
+        }.fillMaxSize()
 
-                                    mapViewState.config.onViewChange(newViewPoint)
+
-                                    mapViewState.viewPointInternal = newViewPoint
+        // 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" }
                                 }
-                                mapViewState.selectRect = null
-                            }
-                        } else {
-                            val dragStart = change.position
-                            val dpPos = DpOffset(dragStart.x.toDp(), dragStart.y.toDp())
-                            mapViewState.config.onClick(
-                                MapViewPoint(
-                                    with(mapViewState) { dpPos.toGeodetic() },
-                                    mapViewState.viewPoint.zoom
-                                )
-                            )
-                            drag(change.id) { dragChange ->
-                                val dragAmount = dragChange.position - dragChange.previousPosition
-                                val newViewPoint = mapViewState.viewPoint.move(
-                                    -dragAmount.x.toDp().value / mapViewState.tileScale,
-                                    +dragAmount.y.toDp().value / mapViewState.tileScale
-                                )
-                                mapViewState.config.onViewChange(newViewPoint)
-                                mapViewState.viewPointInternal = newViewPoint
                             }
                         }
                     }
                 }
             }
         }
-    }.onPointerEvent(PointerEventType.Scroll) {
-        val change = it.changes.first()
-        val (xPos, yPos) = change.position
-        //compute invariant point of translation
-        val invariant = with(mapViewState) { DpOffset(xPos.toDp(), yPos.toDp()).toGeodetic() }
-        val newViewPoint =
-            mapViewState.viewPoint.zoom(-change.scrollDelta.y.toDouble() * mapViewState.config.zoomSpeed, invariant)
-        mapViewState.config.onViewChange(newViewPoint)
-        mapViewState.viewPointInternal = newViewPoint
-    }.fillMaxSize()
 
 
-    // Load tiles asynchronously
+        Canvas(canvasModifier) {
-    LaunchedEffect(mapViewState.viewPoint, mapViewState.canvasSize) {
-        with(mapViewState.mapTileProvider) {
-            val indexRange = 0 until 2.0.pow(mapViewState.zoom).toInt()
-
-            val left =
-                mapViewState.centerCoordinates.x - mapViewState.canvasSize.width.value / 2 / mapViewState.tileScale
-            val right =
-                mapViewState.centerCoordinates.x + mapViewState.canvasSize.width.value / 2 / mapViewState.tileScale
-            val horizontalIndices: IntRange = (toIndex(left)..toIndex(right)).intersect(indexRange)
-
-            val top =
-                (mapViewState.centerCoordinates.y + mapViewState.canvasSize.height.value / 2 / mapViewState.tileScale)
-            val bottom =
-                (mapViewState.centerCoordinates.y - mapViewState.canvasSize.height.value / 2 / mapViewState.tileScale)
-            val verticalIndices: IntRange = (toIndex(bottom)..toIndex(top)).intersect(indexRange)
-
-            mapViewState.mapTiles.clear()
-
-            for (j in verticalIndices) {
-                for (i in horizontalIndices) {
-                    val id = TileId(mapViewState.zoom, i, j)
-                    //start all
-                    val deferred = loadTileAsync(id)
-                    //wait asynchronously for it to finish
-                    launch {
-                        try {
-                            mapViewState.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" }
+                logger.debug { "Recalculate canvas. Size: $size" }
-        }
+            }
-        clipRect {
+            clipRect {
-            val tileSize = IntSize(
+                val tileSize = IntSize(
-                ceil((mapViewState.mapTileProvider.tileSize.dp * mapViewState.tileScale.toFloat()).toPx()).toInt(),
+                    ceil((mapTileProvider.tileSize.dp * tileScale.toFloat()).toPx()).toInt(),
-                ceil((mapViewState.mapTileProvider.tileSize.dp * mapViewState.tileScale.toFloat()).toPx()).toInt()
+                    ceil((mapTileProvider.tileSize.dp * tileScale.toFloat()).toPx()).toInt()
-            )
-            mapViewState.mapTiles.forEach { (id, image) ->
-                //converting back from tile index to screen offset
-                val offset = IntOffset(
-                    (mapViewState.canvasSize.width / 2 + (mapViewState.mapTileProvider.toCoordinate(id.i).dp - mapViewState.centerCoordinates.x.dp) * mapViewState.tileScale.toFloat()).roundToPx(),
-                    (mapViewState.canvasSize.height / 2 + (mapViewState.mapTileProvider.toCoordinate(id.j).dp - mapViewState.centerCoordinates.y.dp) * mapViewState.tileScale.toFloat()).roundToPx()
                 )
-                drawImage(
+                mapTiles.forEach { (id, image) ->
-                    image = image,
+                    //converting back from tile index to screen offset
-                    dstOffset = offset,
+                    val offset = IntOffset(
-                    dstSize = tileSize
+                        (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)
+                    )
                 )
             }
-            mapViewState.features.values.filter { mapViewState.zoom in it.zoomRange }.forEach { feature ->
-                drawFeature(mapViewState.zoom, feature)
-            }
-        }
-        mapViewState.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)
-                )
-            )
         }
     }
-}
+}