Generalize feature draw logic for schemes

build.gradle.kts

@@ -8,7 +8,7 @@ plugins {
 
 allprojects {
     group = "center.sciprog"
-    version = "0.1.1"
+    version = "0.2.0-dev-1"
 }
 
 apiValidation{

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

@@ -8,6 +8,10 @@ import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.window.Window
 import androidx.compose.ui.window.application
+import center.sciprog.maps.features.FeaturesState
+import center.sciprog.maps.features.ViewConfig
+import center.sciprog.maps.features.ViewPoint
+import center.sciprog.maps.features.computeBoundingBox
 import center.sciprog.maps.scheme.*
 import center.sciprog.maps.svg.FeatureStateSnapshot
 import center.sciprog.maps.svg.exportToSvg
@@ -25,7 +29,7 @@ fun App() {
     MaterialTheme {
         val scope = rememberCoroutineScope()
 
-        val schemeFeaturesState = SchemeFeaturesState.remember {
+        val schemeFeaturesState = FeaturesState.remember(XYCoordinateSpace) {
             background(1600f, 1200f) { painterResource("middle-earth.jpg") }
             circle(410.52737 to 868.7676, color = Color.Blue)
             text(410.52737 to 868.7676, "Shire", color = Color.Blue)
@@ -33,14 +37,14 @@ fun App() {
             text(1132.0881 to 394.99127, "Ordruin", color = Color.Red)
             arc(center = 1132.0881 to 394.99127, radius = 20f, startAngle = 0f, 2 * PI.toFloat())
 
-            val hobbitId = circle(410.52737 to 868.7676)
+            circle(410.52737 to 868.7676, id = "hobbit")
 
             scope.launch {
                 var t = 0.0
                 while (isActive) {
                     val x = 410.52737 + t * (1132.0881 - 410.52737)
                     val y = 868.7676 + t * (394.99127 - 868.7676)
-                    circle(x to y, color = Color.Green, id = hobbitId)
+                    circle(x to y, color = Color.Green, id = "hobbit")
                     delay(100)
                     t += 0.005
                     if (t >= 1.0) t = 0.0
@@ -48,14 +52,14 @@ fun App() {
             }
         }
 
-        val initialViewPoint: SchemeViewPoint = remember {
+        val initialViewPoint: ViewPoint<XY> = remember {
-            schemeFeaturesState.features().values.computeBoundingBox(1f)?.computeViewPoint()
+            schemeFeaturesState.features.values.computeBoundingBox(XYCoordinateSpace, 1f)?.computeViewPoint()
-                ?: SchemeViewPoint(SchemeCoordinates(0f, 0f))
+                ?: XYViewPoint(XY(0f, 0f))
         }
 
-        var viewPoint by remember { mutableStateOf<SchemeViewPoint>(initialViewPoint) }
+        var viewPoint: ViewPoint<XY> by remember { mutableStateOf(initialViewPoint) }
 
-        var snapshot: FeatureStateSnapshot? by remember { mutableStateOf(null) }
+        var snapshot: FeatureStateSnapshot<XY>? by remember { mutableStateOf(null) }
 
         if (snapshot == null) {
             snapshot = schemeFeaturesState.snapshot()
@@ -78,7 +82,7 @@ fun App() {
             SchemeView(
                 initialViewPoint = initialViewPoint,
                 featuresState = schemeFeaturesState,
-                config = SchemeViewConfig(
+                config = ViewConfig(
                     onClick = {
                         println("${focus.x}, ${focus.y}")
                     },

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

@@ -8,14 +8,14 @@ import center.sciprog.maps.features.ViewPoint
 import kotlin.math.pow
 
 public object GmcCoordinateSpace : CoordinateSpace<Gmc> {
-    override fun Rectangle(first: Gmc, second: Gmc): GmcRectangle = GmcRectangle(first, second)
+    override fun Rectangle(first: Gmc, second: Gmc): Rectangle<Gmc> = GmcRectangle(first, second)
 
-    override fun Rectangle(center: Gmc, zoom: Double, size: DpSize): GmcRectangle {
+    override fun Rectangle(center: Gmc, zoom: Float, size: DpSize): Rectangle<Gmc> {
         val scale = WebMercatorProjection.scaleFactor(zoom)
-        return buildRectangle(center, (size.width.value / scale).radians, (size.height.value / scale).radians)
+        return Rectangle(center, (size.width.value / scale).radians, (size.height.value / scale).radians)
     }
 
-    override fun ViewPoint(center: Gmc, zoom: Double): ViewPoint<Gmc> = MapViewPoint(center, zoom)
+    override fun ViewPoint(center: Gmc, zoom: Float): ViewPoint<Gmc> = MapViewPoint(center, zoom)
 
     override fun ViewPoint<Gmc>.moveBy(delta: Gmc): ViewPoint<Gmc> {
         val newCoordinates = GeodeticMapCoordinates(
@@ -28,21 +28,19 @@ public object GmcCoordinateSpace : CoordinateSpace<Gmc> {
         return MapViewPoint(newCoordinates, zoom)
     }
 
-    override fun ViewPoint<Gmc>.zoomBy(zoomDelta: Double, invariant: Gmc): ViewPoint<Gmc> = if (invariant == focus) {
+    override fun ViewPoint<Gmc>.zoomBy(zoomDelta: Float, invariant: Gmc): ViewPoint<Gmc> = if (invariant == focus) {
-        ViewPoint(focus, (zoom + zoomDelta).coerceIn(2.0, 18.0) )
+        ViewPoint(focus, (zoom + zoomDelta).coerceIn(2f, 18f) )
     } else {
-        val difScale = (1 - 2.0.pow(-zoomDelta))
+        val difScale = (1 - 2f.pow(-zoomDelta))
         val newCenter = GeodeticMapCoordinates(
             focus.latitude + (invariant.latitude - focus.latitude) * difScale,
             focus.longitude + (invariant.longitude - focus.longitude) * difScale
         )
-        MapViewPoint(newCenter, (zoom + zoomDelta).coerceIn(2.0, 18.0))
+        MapViewPoint(newCenter, (zoom + zoomDelta).coerceIn(2f, 18f))
     }
 
-
+    override fun Rectangle<Gmc>.withCenter(center: Gmc): Rectangle<Gmc> =
-    override fun Rectangle<Gmc>.withCenter(center: Gmc): GmcRectangle {
+        Rectangle(center, height = latitudeDelta, width = longitudeDelta)
-        return buildRectangle(center, height = latitudeDelta, width = longitudeDelta)
-    }
 
     override fun Collection<Rectangle<Gmc>>.wrapRectangles(): Rectangle<Gmc>? {
         if (isEmpty()) return null
@@ -68,24 +66,24 @@ public object GmcCoordinateSpace : CoordinateSpace<Gmc> {
 /**
  * A quasi-square section. Note that latitudinal distance could be imprecise for large distances
  */
-public fun CoordinateSpace<Gmc>.buildRectangle(
+public fun CoordinateSpace<Gmc>.Rectangle(
     center: Gmc,
     height: Distance,
     width: Distance,
     ellipsoid: GeoEllipsoid = GeoEllipsoid.WGS84,
-): GmcRectangle {
+): Rectangle<Gmc> {
     val reducedRadius = ellipsoid.reducedRadius(center.latitude)
-    return buildRectangle(center, (height / ellipsoid.polarRadius).radians, (width / reducedRadius).radians)
+    return Rectangle(center, (height / ellipsoid.polarRadius).radians, (width / reducedRadius).radians)
 }
 
 /**
  * A quasi-square section.
  */
-public fun CoordinateSpace<Gmc>.buildRectangle(
+public fun CoordinateSpace<Gmc>.Rectangle(
     center: GeodeticMapCoordinates,
     height: Angle,
     width: Angle,
-): GmcRectangle {
+): Rectangle<Gmc> {
     val a = GeodeticMapCoordinates(
         center.latitude - (height / 2),
         center.longitude - (width / 2)

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

@@ -12,7 +12,7 @@ import center.sciprog.maps.features.Rectangle
  *
  * Note that this is a rectangle only on a Mercator projection.
  */
-public data class GmcRectangle(
+internal data class GmcRectangle(
     override val a: GeodeticMapCoordinates,
     override val b: GeodeticMapCoordinates,
 ) : Rectangle<Gmc> {

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

@@ -35,7 +35,7 @@ public fun Rectangle<Gmc>.computeViewPoint(
             canvasSize.height.value / latitudeDelta.radians.value
         ) * PI / mapTileProvider.tileSize
     )
-    return MapViewPoint(center, zoom)
+    return MapViewPoint(center, zoom.toFloat())
 }
 
 /**
@@ -45,7 +45,7 @@ public fun Rectangle<Gmc>.computeViewPoint(
 public fun MapView(
     mapTileProvider: MapTileProvider,
     initialViewPoint: MapViewPoint? = null,
-    initialRectangle: GmcRectangle? = null,
+    initialRectangle: Rectangle<Gmc>? = null,
     featureMap: Map<FeatureId<*>, MapFeature>,
     config: ViewConfig<Gmc> = ViewConfig(),
     modifier: Modifier = Modifier.fillMaxSize(),
@@ -59,7 +59,7 @@ public fun MapView(
     val viewPointOverride: MapViewPoint = remember(initialViewPoint, initialRectangle) {
         initialViewPoint
             ?: initialRectangle?.computeViewPoint(mapTileProvider)
-            ?: featureMap.values.computeBoundingBox(GmcCoordinateSpace, 1.0)?.computeViewPoint(mapTileProvider)
+            ?: featureMap.values.computeBoundingBox(GmcCoordinateSpace, 1f)?.computeViewPoint(mapTileProvider)
             ?: MapViewPoint.globe
     }
 
@@ -77,7 +77,7 @@ public fun MapView(
 public fun MapView(
     mapTileProvider: MapTileProvider,
     initialViewPoint: MapViewPoint? = null,
-    initialRectangle: GmcRectangle? = null,
+    initialRectangle: Rectangle<Gmc>? = null,
     config: ViewConfig<Gmc> = ViewConfig(),
     modifier: Modifier = Modifier.fillMaxSize(),
     buildFeatures: FeaturesState<Gmc>.() -> Unit = {},
@@ -87,12 +87,13 @@ public fun MapView(
     val viewPointOverride: MapViewPoint = remember(initialViewPoint, initialRectangle) {
         initialViewPoint
             ?: initialRectangle?.computeViewPoint(mapTileProvider)
-            ?: featureState.features.values.computeBoundingBox(GmcCoordinateSpace,1.0)?.computeViewPoint(mapTileProvider)
+            ?: featureState.features.values.computeBoundingBox(GmcCoordinateSpace,1f)?.computeViewPoint(mapTileProvider)
             ?: MapViewPoint.globe
     }
 
     val featureDrag: DragHandle<Gmc> = DragHandle.withPrimaryButton { event, start: ViewPoint<Gmc>, end: ViewPoint<Gmc> ->
         featureState.forEachWithAttribute(DraggableAttribute) { _, handle ->
+            //TODO add safety
             handle as DragHandle<Gmc>
             if (!handle.handle(event, start, end)) return@withPrimaryButton false
         }

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

@@ -9,12 +9,12 @@ import kotlin.math.pow
  */
 public data class MapViewPoint(
     override val focus: GeodeticMapCoordinates,
-    override val zoom: Double,
+    override val zoom: Float,
 ) : ViewPoint<Gmc>{
     val scaleFactor: Double by lazy { WebMercatorProjection.scaleFactor(zoom) }
 
     public companion object{
-        public val globe: MapViewPoint = MapViewPoint(GeodeticMapCoordinates(0.0.radians, 0.0.radians), 1.0)
+        public val globe: MapViewPoint = MapViewPoint(GeodeticMapCoordinates(0.0.radians, 0.0.radians), 1f)
     }
 }
 
@@ -30,15 +30,15 @@ public fun MapViewPoint.move(delta: GeodeticMapCoordinates): MapViewPoint {
 }
 
 public fun MapViewPoint.zoom(
-    zoomDelta: Double,
+    zoomDelta: Float,
     invariant: GeodeticMapCoordinates = focus,
 ): MapViewPoint = if (invariant == focus) {
-    copy(zoom = (zoom + zoomDelta).coerceIn(2.0, 18.0))
+    copy(zoom = (zoom + zoomDelta).coerceIn(2f, 18f))
 } else {
-    val difScale = (1 - 2.0.pow(-zoomDelta))
+    val difScale = (1 - 2f.pow(-zoomDelta))
     val newCenter = GeodeticMapCoordinates(
         focus.latitude + (invariant.latitude - focus.latitude) * difScale,
         focus.longitude + (invariant.longitude - focus.longitude) * difScale
     )
-    MapViewPoint(newCenter, (zoom + zoomDelta).coerceIn(2.0, 18.0))
+    MapViewPoint(newCenter, (zoom + zoomDelta).coerceIn(2f, 18f))
 }

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

@@ -7,7 +7,7 @@ import center.sciprog.maps.coordinates.*
 import center.sciprog.maps.features.*
 import kotlin.math.*
 
-internal class MapState internal constructor(
+internal class MapViewState internal constructor(
     config: ViewConfig<Gmc>,
     canvasSize: DpSize,
     viewPoint: ViewPoint<Gmc>,
@@ -15,36 +15,36 @@ internal class MapState internal constructor(
 ) : CoordinateViewState<Gmc>(config, canvasSize, viewPoint) {
     override val space: CoordinateSpace<Gmc> get() = GmcCoordinateSpace
 
-    public val scaleFactor: Double
+    val scaleFactor: Double
         get() = WebMercatorProjection.scaleFactor(viewPoint.zoom)
 
     val intZoom: Int get() = floor(zoom).toInt()
 
-    public val centerCoordinates: WebMercatorCoordinates
+    val centerCoordinates: WebMercatorCoordinates
         get() = WebMercatorProjection.toMercator(viewPoint.focus, intZoom)
 
-    internal val tileScale: Double
+    val tileScale: Float
-        get() = 2.0.pow(viewPoint.zoom - floor(viewPoint.zoom))
+        get() = 2f.pow(viewPoint.zoom - floor(viewPoint.zoom))
-
-    private fun DpOffset.toMercator(): WebMercatorCoordinates = WebMercatorCoordinates(
-        intZoom,
-        (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
      */
-    override fun DpOffset.toCoordinates(): Gmc =
+    override fun DpOffset.toCoordinates(): Gmc {
-        WebMercatorProjection.toGeodetic(toMercator())
+        val mercator = WebMercatorCoordinates(
+            intZoom,
+            (x - canvasSize.width / 2).value / tileScale + centerCoordinates.x,
+            (y - canvasSize.height / 2).value / tileScale + centerCoordinates.y,
+        )
+        return WebMercatorProjection.toGeodetic(mercator)
+    }
 
-    internal fun WebMercatorCoordinates.toOffset(): DpOffset = DpOffset(
+    override fun Gmc.toDpOffset(): DpOffset {
-        (canvasSize.width / 2 + (x.dp - centerCoordinates.x.dp) * tileScale.toFloat()),
+        val mercator = WebMercatorProjection.toMercator(this, intZoom)
-        (canvasSize.height / 2 + (y.dp - centerCoordinates.y.dp) * tileScale.toFloat())
+        return  DpOffset(
-    )
+            (canvasSize.width / 2 + (mercator.x.dp - centerCoordinates.x.dp) * tileScale.toFloat()),
-
+            (canvasSize.height / 2 + (mercator.y.dp - centerCoordinates.y.dp) * tileScale.toFloat())
-    override fun Gmc.toDpOffset(): DpOffset =
+        )
-        WebMercatorProjection.toMercator(this, intZoom).toOffset()
+    }
 
     override fun Rectangle<Gmc>.toDpRect(): DpRect {
         val topLeft = topLeft.toDpOffset()
@@ -59,7 +59,7 @@ internal class MapState internal constructor(
                 canvasSize.height.value / rectangle.latitudeDelta.radians.value
             ) * PI / tileSize
         )
-        return MapViewPoint(rectangle.center, zoom)
+        return MapViewPoint(rectangle.center, zoom.toFloat())
     }
 
     override fun ViewPoint<Gmc>.moveBy(x: Dp, y: Dp): ViewPoint<Gmc> {
@@ -82,6 +82,6 @@ internal fun rememberMapState(
     canvasSize: DpSize,
     viewPoint: ViewPoint<Gmc>,
     tileSize: Int,
-): MapState = remember {
+): MapViewState = remember {
-    MapState(config, canvasSize, viewPoint, tileSize)
+    MapViewState(config, canvasSize, viewPoint, tileSize)
 }

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

@@ -84,7 +84,7 @@ public fun FeaturesState<Gmc>.arc(
     id,
     ArcFeature(
         coordinateSpace,
-        oval = buildRectangle(coordinatesOf(center), radius, radius),
+        oval = Rectangle(coordinatesOf(center), radius, radius),
         startAngle = startAngle.radians.toFloat(),
         arcLength = arcLength.radians.toFloat(),
         zoomRange = zoomRange,

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

@@ -8,14 +8,17 @@ import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.PathEffect
 import androidx.compose.ui.graphics.drawscope.Stroke
 import androidx.compose.ui.graphics.drawscope.clipRect
+import androidx.compose.ui.graphics.painter.Painter
 import androidx.compose.ui.graphics.toArgb
 import androidx.compose.ui.graphics.toComposeImageBitmap
-import androidx.compose.ui.graphics.vector.VectorPainter
 import androidx.compose.ui.unit.IntOffset
 import androidx.compose.ui.unit.IntSize
 import androidx.compose.ui.unit.dp
 import center.sciprog.maps.coordinates.Gmc
-import center.sciprog.maps.features.*
+import center.sciprog.maps.features.FeaturesState
+import center.sciprog.maps.features.PainterFeature
+import center.sciprog.maps.features.ViewConfig
+import center.sciprog.maps.features.drawFeature
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.supervisorScope
 import mu.KotlinLogging
@@ -53,6 +56,7 @@ public actual fun MapView(
         initialViewPoint,
         mapTileProvider.tileSize
     )
+
     with(state) {
 
         val mapTiles = remember(mapTileProvider) { mutableStateListOf<MapTile>() }
@@ -96,8 +100,8 @@ public actual fun MapView(
             }
         }
 
-        val painterCache: Map<VectorImageFeature<Gmc>, VectorPainter> = key(featuresState) {
+        val painterCache: Map<PainterFeature<Gmc>, Painter> = key(featuresState) {
-            featuresState.features.values.filterIsInstance<VectorImageFeature<Gmc>>().associateWith { it.painter() }
+            featuresState.features.values.filterIsInstance<PainterFeature<Gmc>>().associateWith { it.painter() }
         }
 
         Canvas(modifier = modifier.mapControls(state).fillMaxSize()) {

maps-kt-core/src/commonMain/kotlin/center/sciprog/maps/coordinates/WebMercatorProjection.kt

@@ -14,10 +14,10 @@ public object WebMercatorProjection {
     /**
      * Compute radians to projection coordinates ratio for given [zoom] factor
      */
-    public fun scaleFactor(zoom: Double): Double = 256.0 / 2 / PI * 2.0.pow(zoom)
+    public fun scaleFactor(zoom: Float): Double = 256.0 / 2 / PI * 2f.pow(zoom)
 
     public fun toGeodetic(mercator: WebMercatorCoordinates): GeodeticMapCoordinates {
-        val scaleFactor = scaleFactor(mercator.zoom.toDouble())
+        val scaleFactor = scaleFactor(mercator.zoom.toFloat())
         val longitude = mercator.x / scaleFactor - PI
         val latitude = (atan(exp(PI - mercator.y / scaleFactor)) - PI / 4) * 2
         return GeodeticMapCoordinates.ofRadians(latitude, longitude)
@@ -29,7 +29,7 @@ public object WebMercatorProjection {
     public fun toMercator(gmc: GeodeticMapCoordinates, zoom: Int): WebMercatorCoordinates {
         require(abs(gmc.latitude) <= MercatorProjection.MAXIMUM_LATITUDE) { "Latitude exceeds the maximum latitude for mercator coordinates" }
 
-        val scaleFactor = scaleFactor(zoom.toDouble())
+        val scaleFactor = scaleFactor(zoom.toFloat())
         return WebMercatorCoordinates(
             zoom = zoom,
             x = scaleFactor * (gmc.longitude.radians.value + PI),

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

@@ -29,17 +29,17 @@ public interface CoordinateSpace<T : Any> {
     /**
      * Build a rectangle of visual size [size]
      */
-    public fun Rectangle(center: T, zoom: Double, size: DpSize): Rectangle<T>
+    public fun Rectangle(center: T, zoom: Float, size: DpSize): Rectangle<T>
 
     /**
      * Create a [ViewPoint] associated with this coordinate space.
      */
-    public fun ViewPoint(center: T, zoom: Double): ViewPoint<T>
+    public fun ViewPoint(center: T, zoom: Float): ViewPoint<T>
 
     public fun ViewPoint<T>.moveBy(delta: T): ViewPoint<T>
 
     public fun ViewPoint<T>.zoomBy(
-        zoomDelta: Double,
+        zoomDelta: Float,
         invariant: T = focus,
     ): ViewPoint<T>
 

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

@@ -25,7 +25,7 @@ public abstract class CoordinateViewState<T : Any>(
             viewPointState.value = value
         }
 
-    public val zoom: Double get() = viewPoint.zoom
+    public val zoom: Float get() = viewPoint.zoom
 
     public abstract fun DpOffset.toCoordinates(): T
 

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

@@ -6,6 +6,7 @@ import androidx.compose.ui.graphics.*
 import androidx.compose.ui.graphics.drawscope.DrawScope
 import androidx.compose.ui.graphics.drawscope.DrawStyle
 import androidx.compose.ui.graphics.drawscope.Fill
+import androidx.compose.ui.graphics.painter.Painter
 import androidx.compose.ui.graphics.vector.ImageVector
 import androidx.compose.ui.graphics.vector.VectorPainter
 import androidx.compose.ui.graphics.vector.rememberVectorPainter
@@ -14,24 +15,30 @@ import androidx.compose.ui.unit.DpSize
 import androidx.compose.ui.unit.dp
 import center.sciprog.maps.features.Feature.Companion.defaultZoomRange
 
-public typealias DoubleRange = ClosedFloatingPointRange<Double>
+public typealias DoubleRange = FloatRange
+public typealias FloatRange = ClosedFloatingPointRange<Float>
 
 public interface Feature<T : Any> {
     public interface Attribute<T>
 
     public val space: CoordinateSpace<T>
 
-    public val zoomRange: DoubleRange
+    public val zoomRange: FloatRange
 
     public var attributes: AttributeMap
 
-    public fun getBoundingBox(zoom: Double): Rectangle<T>?
+    public fun getBoundingBox(zoom: Float): Rectangle<T>?
 
     public companion object {
-        public val defaultZoomRange: ClosedFloatingPointRange<Double> = 1.0..Double.POSITIVE_INFINITY
+        public val defaultZoomRange: FloatRange = 0f..Float.POSITIVE_INFINITY
     }
 }
 
+public interface PainterFeature<T:Any>: Feature<T> {
+    @Composable
+    public fun painter(): Painter
+}
+
 public interface SelectableFeature<T : Any> : Feature<T> {
     public operator fun contains(point: ViewPoint<T>): Boolean = getBoundingBox(point.zoom)?.let {
         point.focus in it
@@ -44,7 +51,7 @@ public interface DraggableFeature<T : Any> : SelectableFeature<T> {
 
 public fun <T : Any> Iterable<Feature<T>>.computeBoundingBox(
     space: CoordinateSpace<T>,
-    zoom: Double,
+    zoom: Float,
 ): Rectangle<T>? = with(space) {
     mapNotNull { it.getBoundingBox(zoom) }.wrapRectangles()
 }
@@ -59,11 +66,11 @@ public fun <T : Any> Iterable<Feature<T>>.computeBoundingBox(
 public class FeatureSelector<T : Any>(
     override val space: CoordinateSpace<T>,
     override var attributes: AttributeMap = AttributeMap(),
-    public val selector: (zoom: Double) -> Feature<T>,
+    public val selector: (zoom: Float) -> Feature<T>,
 ) : Feature<T> {
-    override val zoomRange: ClosedFloatingPointRange<Double> get() = defaultZoomRange
+    override val zoomRange: FloatRange get() = defaultZoomRange
 
-    override fun getBoundingBox(zoom: Double): Rectangle<T>? = selector(zoom).getBoundingBox(zoom)
+    override fun getBoundingBox(zoom: Float): Rectangle<T>? = selector(zoom).getBoundingBox(zoom)
 }
 
 public class PathFeature<T : Any>(
@@ -73,7 +80,7 @@ public class PathFeature<T : Any>(
     public val brush: Brush,
     public val style: DrawStyle = Fill,
     public val targetRect: Rect = path.getBounds(),
-    override val zoomRange: ClosedFloatingPointRange<Double> = defaultZoomRange,
+    override val zoomRange: FloatRange = defaultZoomRange,
     override var attributes: AttributeMap = AttributeMap(),
 ) : DraggableFeature<T> {
     override fun withCoordinates(newCoordinates: T): Feature<T> = with(space) {
@@ -88,20 +95,20 @@ public class PathFeature<T : Any>(
         )
     }
 
-    override fun getBoundingBox(zoom: Double): Rectangle<T> = rectangle
+    override fun getBoundingBox(zoom: Float): Rectangle<T> = rectangle
 
 }
 
 public class PointsFeature<T : Any>(
     override val space: CoordinateSpace<T>,
     public val points: List<T>,
-    override val zoomRange: ClosedFloatingPointRange<Double> = defaultZoomRange,
+    override val zoomRange: FloatRange = defaultZoomRange,
     public val stroke: Float = 2f,
     public val color: Color = Color.Red,
     public val pointMode: PointMode = PointMode.Points,
     override var attributes: AttributeMap = AttributeMap(),
 ) : Feature<T> {
-    override fun getBoundingBox(zoom: Double): Rectangle<T>? = with(space) {
+    override fun getBoundingBox(zoom: Float): Rectangle<T>? = with(space) {
         points.wrapPoints()
     }
 }
@@ -109,12 +116,12 @@ public class PointsFeature<T : Any>(
 public data class CircleFeature<T : Any>(
     override val space: CoordinateSpace<T>,
     public val center: T,
-    override val zoomRange: ClosedFloatingPointRange<Double> = defaultZoomRange,
+    override val zoomRange: FloatRange = defaultZoomRange,
     public val size: Dp = 5.dp,
     public val color: Color = Color.Red,
     override var attributes: AttributeMap = AttributeMap(),
 ) : DraggableFeature<T> {
-    override fun getBoundingBox(zoom: Double): Rectangle<T> =
+    override fun getBoundingBox(zoom: Float): Rectangle<T> =
         space.Rectangle(center, zoom, DpSize(size, size))
 
     override fun withCoordinates(newCoordinates: T): Feature<T> =
@@ -124,12 +131,12 @@ public data class CircleFeature<T : Any>(
 public class RectangleFeature<T : Any>(
     override val space: CoordinateSpace<T>,
     public val center: T,
-    override val zoomRange: ClosedFloatingPointRange<Double> = defaultZoomRange,
+    override val zoomRange: FloatRange = defaultZoomRange,
     public val size: DpSize = DpSize(5.dp, 5.dp),
     public val color: Color = Color.Red,
     override var attributes: AttributeMap = AttributeMap(),
 ) : DraggableFeature<T> {
-    override fun getBoundingBox(zoom: Double): Rectangle<T> =
+    override fun getBoundingBox(zoom: Float): Rectangle<T> =
         space.Rectangle(center, zoom, size)
 
     override fun withCoordinates(newCoordinates: T): Feature<T> =
@@ -140,11 +147,11 @@ public class LineFeature<T : Any>(
     override val space: CoordinateSpace<T>,
     public val a: T,
     public val b: T,
-    override val zoomRange: ClosedFloatingPointRange<Double> = defaultZoomRange,
+    override val zoomRange: FloatRange = defaultZoomRange,
     public val color: Color = Color.Red,
     override var attributes: AttributeMap = AttributeMap(),
 ) : SelectableFeature<T> {
-    override fun getBoundingBox(zoom: Double): Rectangle<T> =
+    override fun getBoundingBox(zoom: Float): Rectangle<T> =
         space.Rectangle(a, b)
 
     override fun contains(point: ViewPoint<T>): Boolean {
@@ -161,26 +168,25 @@ public class ArcFeature<T : Any>(
     public val oval: Rectangle<T>,
     public val startAngle: Float,
     public val arcLength: Float,
-    override val zoomRange: ClosedFloatingPointRange<Double> = defaultZoomRange,
+    override val zoomRange: FloatRange = defaultZoomRange,
     public val color: Color = Color.Red,
     override var attributes: AttributeMap = AttributeMap(),
 ) : DraggableFeature<T> {
-    override fun getBoundingBox(zoom: Double): Rectangle<T> = oval
+    override fun getBoundingBox(zoom: Float): Rectangle<T> = oval
 
     override fun withCoordinates(newCoordinates: T): Feature<T> = with(space) {
         ArcFeature(space, oval.withCenter(newCoordinates), startAngle, arcLength, zoomRange, color, attributes)
     }
 }
 
-
 public data class DrawFeature<T : Any>(
     override val space: CoordinateSpace<T>,
     public val position: T,
-    override val zoomRange: ClosedFloatingPointRange<Double> = defaultZoomRange,
+    override val zoomRange: FloatRange = defaultZoomRange,
     override var attributes: AttributeMap = AttributeMap(),
     public val drawFeature: DrawScope.() -> Unit,
 ) : DraggableFeature<T> {
-    override fun getBoundingBox(zoom: Double): Rectangle<T> = space.Rectangle(position, position)
+    override fun getBoundingBox(zoom: Float): Rectangle<T> = space.Rectangle(position, position)
 
     override fun withCoordinates(newCoordinates: T): Feature<T> = copy(position = newCoordinates)
 }
@@ -190,10 +196,10 @@ public data class BitmapImageFeature<T : Any>(
     public val position: T,
     public val size: DpSize,
     public val image: ImageBitmap,
-    override val zoomRange: ClosedFloatingPointRange<Double> = defaultZoomRange,
+    override val zoomRange: FloatRange = defaultZoomRange,
     override var attributes: AttributeMap = AttributeMap(),
 ) : DraggableFeature<T> {
-    override fun getBoundingBox(zoom: Double): Rectangle<T> = space.Rectangle(position, zoom, size)
+    override fun getBoundingBox(zoom: Float): Rectangle<T> = space.Rectangle(position, zoom, size)
 
     override fun withCoordinates(newCoordinates: T): Feature<T> = copy(position = newCoordinates)
 }
@@ -203,27 +209,46 @@ public data class VectorImageFeature<T : Any>(
     public val position: T,
     public val size: DpSize,
     public val image: ImageVector,
-    override val zoomRange: ClosedFloatingPointRange<Double> = defaultZoomRange,
+    override val zoomRange: FloatRange = defaultZoomRange,
     override var attributes: AttributeMap = AttributeMap(),
-) : DraggableFeature<T> {
+) : DraggableFeature<T>, PainterFeature<T> {
-    override fun getBoundingBox(zoom: Double): Rectangle<T> = space.Rectangle(position, zoom, size)
+    override fun getBoundingBox(zoom: Float): Rectangle<T> = space.Rectangle(position, zoom, size)
 
     override fun withCoordinates(newCoordinates: T): Feature<T> = copy(position = newCoordinates)
 
     @Composable
-    public fun painter(): VectorPainter = rememberVectorPainter(image)
+    override fun painter(): VectorPainter = rememberVectorPainter(image)
 }
 
+/**
+ * A background image that is bound to coordinates and is scaled together with them
+ *
+ * @param rectangle the size of background in scheme size units. The screen units to scheme units ratio equals scale.
+ */
+public class ScalableImageFeature<T: Any>(
+    override val space: CoordinateSpace<T>,
+    public val rectangle: Rectangle<T>,
+    override val zoomRange: FloatRange = defaultZoomRange,
+    override var attributes: AttributeMap = AttributeMap(),
+    public val painter: @Composable () -> Painter,
+) : Feature<T>, PainterFeature<T>{
+    @Composable
+    override fun painter(): Painter  = painter.invoke()
+
+    override fun getBoundingBox(zoom: Float): Rectangle<T> =rectangle
+}
+
+
 /**
  * A group of other features
  */
 public class FeatureGroup<T : Any>(
     override val space: CoordinateSpace<T>,
     public val children: Map<FeatureId<*>, Feature<T>>,
-    override val zoomRange: ClosedFloatingPointRange<Double> = defaultZoomRange,
+    override val zoomRange: FloatRange = defaultZoomRange,
     override var attributes: AttributeMap = AttributeMap(),
 ) : Feature<T> {
-    override fun getBoundingBox(zoom: Double): Rectangle<T>? = with(space) {
+    override fun getBoundingBox(zoom: Float): Rectangle<T>? = with(space) {
         children.values.mapNotNull { it.getBoundingBox(zoom) }.wrapRectangles()
     }
 }
@@ -232,12 +257,12 @@ public class TextFeature<T : Any>(
     override val space: CoordinateSpace<T>,
     public val position: T,
     public val text: String,
-    override val zoomRange: ClosedFloatingPointRange<Double> = defaultZoomRange,
+    override val zoomRange: FloatRange = defaultZoomRange,
     public val color: Color = Color.Black,
     override var attributes: AttributeMap = AttributeMap(),
     public val fontConfig: FeatureFont.() -> Unit,
 ) : DraggableFeature<T> {
-    override fun getBoundingBox(zoom: Double): Rectangle<T> = space.Rectangle(position, position)
+    override fun getBoundingBox(zoom: Float): Rectangle<T> = space.Rectangle(position, position)
 
     override fun withCoordinates(newCoordinates: T): Feature<T> =
         TextFeature(space, newCoordinates, text, zoomRange, color, attributes, fontConfig)

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

@@ -5,6 +5,8 @@ import androidx.compose.runtime.mutableStateMapOf
 import androidx.compose.runtime.remember
 import androidx.compose.ui.graphics.Color
 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
 import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.DpSize
@@ -133,7 +135,7 @@ public class FeaturesState<T : Any>(public val coordinateSpace: CoordinateSpace<
 
 public fun <T : Any> FeaturesState<T>.circle(
     center: T,
-    zoomRange: DoubleRange = defaultZoomRange,
+    zoomRange: FloatRange = defaultZoomRange,
     size: Dp = 5.dp,
     color: Color = Color.Red,
     id: String? = null,
@@ -143,7 +145,7 @@ public fun <T : Any> FeaturesState<T>.circle(
 
 public fun <T : Any> FeaturesState<T>.rectangle(
     centerCoordinates: T,
-    zoomRange: DoubleRange = defaultZoomRange,
+    zoomRange: FloatRange = defaultZoomRange,
     size: DpSize = DpSize(5.dp, 5.dp),
     color: Color = Color.Red,
     id: String? = null,
@@ -151,10 +153,20 @@ public fun <T : Any> FeaturesState<T>.rectangle(
     id, RectangleFeature(coordinateSpace, centerCoordinates, zoomRange, size, color)
 )
 
+public fun <T : Any> FeaturesState<T>.draw(
+    position: T,
+    zoomRange: FloatRange = defaultZoomRange,
+    id: String? = null,
+    draw: DrawScope.() -> Unit,
+): FeatureId<DrawFeature<T>> = feature(
+    id,
+    DrawFeature(coordinateSpace, position, zoomRange, drawFeature = draw)
+)
+
 public fun <T : Any> FeaturesState<T>.line(
     aCoordinates: T,
     bCoordinates: T,
-    zoomRange: DoubleRange = defaultZoomRange,
+    zoomRange: FloatRange = defaultZoomRange,
     color: Color = Color.Red,
     id: String? = null,
 ): FeatureId<LineFeature<T>> = feature(
@@ -166,7 +178,7 @@ public fun <T : Any> FeaturesState<T>.arc(
     oval: Rectangle<T>,
     startAngle: Float,
     arcLength: Float,
-    zoomRange: DoubleRange = defaultZoomRange,
+    zoomRange: FloatRange = defaultZoomRange,
     color: Color = Color.Red,
     id: String? = null,
 ): FeatureId<ArcFeature<T>> = feature(
@@ -176,7 +188,7 @@ public fun <T : Any> FeaturesState<T>.arc(
 
 public fun <T : Any> FeaturesState<T>.points(
     points: List<T>,
-    zoomRange: DoubleRange = defaultZoomRange,
+    zoomRange: FloatRange = defaultZoomRange,
     stroke: Float = 2f,
     color: Color = Color.Red,
     pointMode: PointMode = PointMode.Points,
@@ -187,7 +199,8 @@ public fun <T : Any> FeaturesState<T>.points(
 public fun <T : Any> FeaturesState<T>.image(
     position: T,
     image: ImageVector,
-    zoomRange: DoubleRange = defaultZoomRange,
+    zoomRange: FloatRange = defaultZoomRange,
+    size: DpSize = DpSize(image.defaultWidth, image.defaultHeight),
     id: String? = null,
 ): FeatureId<VectorImageFeature<T>> =
     feature(
@@ -195,14 +208,14 @@ public fun <T : Any> FeaturesState<T>.image(
         VectorImageFeature(
             coordinateSpace,
             position,
-            DpSize(image.defaultWidth, image.defaultHeight),
+            size,
             image,
             zoomRange
         )
     )
 
 public fun <T : Any> FeaturesState<T>.group(
-    zoomRange: DoubleRange = defaultZoomRange,
+    zoomRange: FloatRange = defaultZoomRange,
     id: String? = null,
     builder: FeaturesState<T>.() -> Unit,
 ): FeatureId<FeatureGroup<T>> {
@@ -211,10 +224,20 @@ public fun <T : Any> FeaturesState<T>.group(
     return feature(id, feature)
 }
 
+public fun <T : Any> FeaturesState<T>.scalableImage(
+    box: Rectangle<T>,
+    zoomRange: FloatRange = defaultZoomRange,
+    id: String? = null,
+    painter: @Composable () -> Painter,
+): FeatureId<ScalableImageFeature<T>> = feature(
+    id,
+    ScalableImageFeature<T>(coordinateSpace, box, zoomRange, painter = painter)
+)
+
 public fun <T : Any> FeaturesState<T>.text(
     position: T,
     text: String,
-    zoomRange: DoubleRange = defaultZoomRange,
+    zoomRange: FloatRange = defaultZoomRange,
     color: Color = Color.Red,
     font: FeatureFont.() -> Unit = { size = 16f },
     id: String? = null,

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

@@ -4,7 +4,7 @@ import androidx.compose.ui.input.pointer.PointerEvent
 import androidx.compose.ui.unit.DpSize
 
 public data class ViewConfig<T : Any>(
-    val zoomSpeed: Double = 1.0 / 3.0,
+    val zoomSpeed: Float = 1f / 3f,
     val onClick: ViewPoint<T>.(PointerEvent) -> Unit = {},
     val dragHandle: DragHandle<T> = DragHandle.bypass(),
     val onViewChange: ViewPoint<T>.() -> Unit = {},

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

@@ -5,5 +5,5 @@ package center.sciprog.maps.features
  */
 public interface ViewPoint<T: Any> {
     public val focus: T
-    public val zoom: Double
+    public val zoom: Float
 }

maps-kt-features/src/jvmMain/kotlin/center/sciprog/maps/compose/mapControls.kt

@@ -1,4 +1,4 @@
-package center.sciprog.maps.features
+package center.sciprog.maps.compose
 
 import androidx.compose.foundation.gestures.drag
 import androidx.compose.foundation.gestures.forEachGesture
@@ -8,6 +8,9 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.geometry.Offset
 import androidx.compose.ui.input.pointer.*
 import androidx.compose.ui.unit.*
+import center.sciprog.maps.features.CoordinateViewState
+import center.sciprog.maps.features.bottomRight
+import center.sciprog.maps.features.topLeft
 import kotlin.math.max
 import kotlin.math.min
 
@@ -24,7 +27,7 @@ public fun <T : Any> Modifier.mapControls(
                 val event: PointerEvent = awaitPointerEvent()
 
                 event.changes.forEach { change ->
-                    val dragStart = change.position
+                    //val dragStart = change.position
                     //val dpPos = DpOffset(dragStart.x.toDp(), dragStart.y.toDp())
 
                     //start selection
@@ -95,7 +98,7 @@ public fun <T : Any> Modifier.mapControls(
         //compute invariant point of translation
         val invariant = DpOffset(xPos.toDp(), yPos.toDp()).toCoordinates()
         viewPoint = with(space) {
-            viewPoint.zoomBy(-change.scrollDelta.y.toDouble() * config.zoomSpeed, invariant)
+            viewPoint.zoomBy(-change.scrollDelta.y * config.zoomSpeed, invariant)
         }
     }
 }

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

@@ -8,8 +8,8 @@ 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.graphics.painter.Painter
 import androidx.compose.ui.graphics.toArgb
-import androidx.compose.ui.graphics.vector.VectorPainter
 import org.jetbrains.skia.Font
 import org.jetbrains.skia.Paint
 import kotlin.math.PI
@@ -22,7 +22,7 @@ internal fun Color.toPaint(): Paint = Paint().apply {
 
 public fun <T : Any> DrawScope.drawFeature(
     state: CoordinateViewState<T>,
-    painterCache: Map<VectorImageFeature<T>, VectorPainter>,
+    painterCache: Map<PainterFeature<T>, Painter>,
     feature: Feature<T>,
 ): Unit = with(state) {
     fun T.toOffset(): Offset = toOffset(this@drawFeature)
@@ -117,6 +117,17 @@ public fun <T : Any> DrawScope.drawFeature(
             )
         }
 
+        is ScalableImageFeature -> {
+            val rect = feature.rectangle.toDpRect().toRect()
+            val offset = rect.topLeft
+
+            translate(offset.x, offset.y) {
+                with(painterCache[feature]!!) {
+                    draw(rect.size)
+                }
+            }
+        }
+
         else -> {
             //logger.error { "Unrecognized feature type: ${feature::class}" }
         }

maps-kt-scheme/build.gradle.kts

@@ -16,6 +16,7 @@ kotlin {
     sourceSets {
         commonMain {
             dependencies {
+                api(projects.mapsKtFeatures)
                 api("io.github.microutils:kotlin-logging:2.1.23")
                 api(compose.foundation)
             }

maps-kt-scheme/src/commonMain/kotlin/center/sciprog/maps/scheme/SchemeCoordinates.kt

@@ -1,61 +0,0 @@
-package center.sciprog.maps.scheme
-
-import androidx.compose.ui.unit.DpSize
-import androidx.compose.ui.unit.dp
-import kotlin.math.abs
-import kotlin.math.max
-import kotlin.math.min
-
-data class SchemeCoordinates(val x: Float, val y: Float)
-
-data class SchemeRectangle(
-    val a: SchemeCoordinates,
-    val b: SchemeCoordinates,
-) {
-    companion object {
-        fun square(center: SchemeCoordinates, height: Float, width: Float): SchemeRectangle = SchemeRectangle(
-            SchemeCoordinates(center.x - width / 2, center.y + height / 2),
-            SchemeCoordinates(center.x + width / 2, center.y - height / 2),
-        )
-    }
-}
-
-val SchemeRectangle.top get() = max(a.y, b.y)
-val SchemeRectangle.bottom get() = min(a.y, b.y)
-
-val SchemeRectangle.right get() = max(a.x, b.x)
-val SchemeRectangle.left get() = min(a.x, b.x)
-
-val SchemeRectangle.width get() = abs(a.x - b.x)
-val SchemeRectangle.height get() = abs(a.y - b.y)
-
-val SchemeRectangle.center get() = SchemeCoordinates((a.x + b.x) / 2, (a.y + b.y) / 2)
-
-public val SchemeRectangle.leftTop: SchemeCoordinates get() = SchemeCoordinates(left, top)
-public val SchemeRectangle.rightBottom: SchemeCoordinates get() = SchemeCoordinates(right, bottom)
-
-fun Collection<SchemeRectangle>.wrapAll(): SchemeRectangle? {
-    if (isEmpty()) return null
-    val minX = minOf { it.left }
-    val maxX = maxOf { it.right }
-
-    val minY = minOf { it.bottom }
-    val maxY = maxOf { it.top }
-    return SchemeRectangle(
-        SchemeCoordinates(minX, minY),
-        SchemeCoordinates(maxX, maxY)
-    )
-}
-
-internal val defaultCanvasSize = DpSize(512.dp, 512.dp)
-
-public fun SchemeRectangle.computeViewPoint(
-    canvasSize: DpSize = defaultCanvasSize,
-): SchemeViewPoint {
-    val scale = min(
-        canvasSize.width.value / width,
-        canvasSize.height.value / height
-    )
-
-    return SchemeViewPoint(center, scale)
-}

maps-kt-scheme/src/commonMain/kotlin/center/sciprog/maps/scheme/SchemeFeature.kt

@@ -1,136 +0,0 @@
-package center.sciprog.maps.scheme
-
-import androidx.compose.runtime.Composable
-import androidx.compose.ui.graphics.Color
-import androidx.compose.ui.graphics.ImageBitmap
-import androidx.compose.ui.graphics.drawscope.DrawScope
-import androidx.compose.ui.graphics.painter.Painter
-import androidx.compose.ui.graphics.vector.ImageVector
-import androidx.compose.ui.graphics.vector.rememberVectorPainter
-import androidx.compose.ui.unit.DpSize
-import androidx.compose.ui.unit.IntSize
-import androidx.compose.ui.unit.dp
-import center.sciprog.maps.scheme.SchemeFeature.Companion.defaultScaleRange
-
-internal typealias FloatRange = ClosedFloatingPointRange<Float>
-
-sealed class SchemeFeature(val scaleRange: FloatRange) {
-    abstract fun getBoundingBox(scale: Float): SchemeRectangle?
-
-    companion object {
-        val defaultScaleRange = 0f..Float.MAX_VALUE
-    }
-}
-
-
-fun Iterable<SchemeFeature>.computeBoundingBox(scale: Float): SchemeRectangle? =
-    mapNotNull { it.getBoundingBox(scale) }.wrapAll()
-
-
-internal fun Pair<Number, Number>.toCoordinates() = SchemeCoordinates(first.toFloat(), second.toFloat())
-
-interface PainterFeature {
-    val painter: @Composable () -> Painter
-}
-
-/**
- * A background image that is bound to scheme coordinates and is scaled together with them
- *
- * @param rectangle the size of background in scheme size units. The screen units to scheme units ratio equals scale.
- */
-class SchemeBackgroundFeature(
-    val rectangle: SchemeRectangle,
-    scaleRange: FloatRange = defaultScaleRange,
-    override val painter: @Composable () -> Painter,
-) : SchemeFeature(scaleRange), PainterFeature {
-    override fun getBoundingBox(scale: Float): SchemeRectangle = rectangle
-}
-
-class SchemeFeatureSelector(val selector: (scale: Float) -> SchemeFeature) : SchemeFeature(defaultScaleRange) {
-    override fun getBoundingBox(scale: Float): SchemeRectangle? = selector(scale).getBoundingBox(scale)
-}
-
-class SchemeDrawFeature(
-    val position: SchemeCoordinates,
-    scaleRange: FloatRange = defaultScaleRange,
-    val drawFeature: DrawScope.() -> Unit,
-) : SchemeFeature(scaleRange) {
-    override fun getBoundingBox(scale: Float): SchemeRectangle = SchemeRectangle(position, position)
-}
-
-class SchemeCircleFeature(
-    val center: SchemeCoordinates,
-    scaleRange: FloatRange = defaultScaleRange,
-    val size: Float = 5f,
-    val color: Color = Color.Red,
-) : SchemeFeature(scaleRange) {
-    override fun getBoundingBox(scale: Float): SchemeRectangle = SchemeRectangle(center, center)
-}
-
-class SchemeLineFeature(
-    val a: SchemeCoordinates,
-    val b: SchemeCoordinates,
-    scaleRange: FloatRange = defaultScaleRange,
-    val color: Color = Color.Red,
-) : SchemeFeature(scaleRange) {
-    override fun getBoundingBox(scale: Float): SchemeRectangle = SchemeRectangle(a, b)
-}
-
-/**
- * @param startAngle the angle in radians from parallel downwards for the start of the arc
- * @param arcLength arc length in radians
- */
-public class SchemeArcFeature(
-    public val oval: SchemeRectangle,
-    public val startAngle: Float,
-    public val arcLength: Float,
-    scaleRange: FloatRange = defaultScaleRange,
-    public val color: Color = Color.Red,
-) : SchemeFeature(scaleRange) {
-    override fun getBoundingBox(scale: Float): SchemeRectangle = oval
-}
-
-class SchemeTextFeature(
-    val position: SchemeCoordinates,
-    val text: String,
-    scaleRange: FloatRange = defaultScaleRange,
-    val color: Color = Color.Red,
-) : SchemeFeature(scaleRange) {
-    override fun getBoundingBox(scale: Float): SchemeRectangle = SchemeRectangle(position, position)
-}
-
-class SchemeBitmapFeature(
-    val position: SchemeCoordinates,
-    val image: ImageBitmap,
-    val size: IntSize = IntSize(15, 15),
-    scaleRange: FloatRange = defaultScaleRange,
-) : SchemeFeature(scaleRange) {
-    override fun getBoundingBox(scale: Float): SchemeRectangle = SchemeRectangle(position, position)
-}
-
-class SchemeImageFeature(
-    val position: SchemeCoordinates,
-    val size: DpSize,
-    scaleRange: FloatRange = defaultScaleRange,
-    override val painter: @Composable () -> Painter,
-) : SchemeFeature(scaleRange), PainterFeature {
-    override fun getBoundingBox(scale: Float): SchemeRectangle = SchemeRectangle(position, position)
-}
-
-fun SchemeImageFeature(
-    position: SchemeCoordinates,
-    image: ImageVector,
-    size: DpSize = DpSize(20.dp, 20.dp),
-    scaleRange: FloatRange = defaultScaleRange,
-): SchemeImageFeature = SchemeImageFeature(position, size, scaleRange) { rememberVectorPainter(image) }
-
-/**
- * A group of other features
- */
-class SchemeFeatureGroup(
-    val children: Map<FeatureId, SchemeFeature>,
-    scaleRange: FloatRange = defaultScaleRange,
-) : SchemeFeature(scaleRange) {
-    override fun getBoundingBox(scale: Float): SchemeRectangle? =
-        children.values.mapNotNull { it.getBoundingBox(scale) }.wrapAll()
-}

maps-kt-scheme/src/commonMain/kotlin/center/sciprog/maps/scheme/SchemeFeatureState.kt

@@ -1,206 +1,85 @@
 package center.sciprog.maps.scheme
 
 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.drawscope.DrawScope
 import androidx.compose.ui.graphics.painter.Painter
 import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.DpSize
 import androidx.compose.ui.unit.dp
-import center.sciprog.maps.scheme.SchemeFeature.Companion.defaultScaleRange
+import center.sciprog.maps.features.*
 
-typealias FeatureId = String
+internal fun Pair<Number, Number>.toCoordinates(): XY = XY(first.toFloat(), second.toFloat())
 
-
+fun FeaturesState<XY>.background(
-public class SchemeFeaturesState internal constructor(
-    private val features: MutableMap<FeatureId, SchemeFeature>,
-    private val attributes: MutableMap<FeatureId, SnapshotStateMap<Attribute<out Any?>, in Any?>>,
-) {
-    public interface Attribute<T>
-
-    public fun features(): Map<FeatureId, SchemeFeature> = features
-
-
-    private fun generateID(feature: SchemeFeature): FeatureId = "@feature[${feature.hashCode().toUInt()}]"
-
-    public fun addFeature(id: FeatureId?, feature: SchemeFeature): FeatureId {
-        val safeId = id ?: generateID(feature)
-        features[id ?: generateID(feature)] = feature
-        return safeId
-    }
-
-    public fun <T> setAttribute(id: FeatureId, key: Attribute<T>, value: T) {
-        attributes.getOrPut(id) { mutableStateMapOf() }[key] = value
-    }
-
-    @Suppress("UNCHECKED_CAST")
-    public fun <T> getAttribute(id: FeatureId, key: Attribute<T>): T? =
-        attributes[id]?.get(key)?.let { it as T }
-
-    @Suppress("UNCHECKED_CAST")
-    public fun <T> findAllWithAttribute(key: Attribute<T>, condition: (T) -> Boolean): Set<FeatureId> {
-        return attributes.filterValues {
-            condition(it[key] as T)
-        }.keys
-    }
-
-    public companion object {
-
-        /**
-         * Build, but do not remember map feature state
-         */
-        public fun build(
-            builder: SchemeFeaturesState.() -> Unit = {},
-        ): SchemeFeaturesState = SchemeFeaturesState(
-            mutableStateMapOf(),
-            mutableStateMapOf()
-        ).apply(builder)
-
-        /**
-         * Build and remember map feature state
-         */
-        @Composable
-        public fun remember(
-            builder: SchemeFeaturesState.() -> Unit = {},
-        ): SchemeFeaturesState = androidx.compose.runtime.remember(builder) {
-            build(builder)
-        }
-
-    }
-}
-
-fun SchemeFeaturesState.background(
-    box: SchemeRectangle,
-    id: FeatureId? = null,
-    painter: @Composable () -> Painter,
-): FeatureId = addFeature(
-    id,
-    SchemeBackgroundFeature(box, painter = painter)
-)
-
-fun SchemeFeaturesState.background(
     width: Float,
     height: Float,
-    offset: SchemeCoordinates = SchemeCoordinates(0f, 0f),
+    offset: XY = XY(0f, 0f),
-    id: FeatureId? = null,
+    id: String? = null,
     painter: @Composable () -> Painter,
-): FeatureId {
+): FeatureId<ScalableImageFeature<XY>> {
-    val box = SchemeRectangle(
+    val box = XYRectangle(
         offset,
-        SchemeCoordinates(width + offset.x, height + offset.y)
+        XY(width + offset.x, height + offset.y)
     )
-    return background(box, id, painter = painter)
+    return scalableImage(box, id = id, painter = painter)
 }
 
-fun SchemeFeaturesState.circle(
+fun FeaturesState<XY>.circle(
-    center: SchemeCoordinates,
-    scaleRange: FloatRange = defaultScaleRange,
-    size: Float = 5f,
-    color: Color = Color.Red,
-    id: FeatureId? = null,
-) = addFeature(
-    id, SchemeCircleFeature(center, scaleRange, size, color)
-)
-
-fun SchemeFeaturesState.circle(
     centerCoordinates: Pair<Number, Number>,
-    scaleRange: FloatRange = defaultScaleRange,
+    zoomRange: FloatRange = Feature.defaultZoomRange,
-    size: Float = 5f,
+    size: Dp = 5.dp,
     color: Color = Color.Red,
-    id: FeatureId? = null,
+    id: String? = null,
-) = addFeature(
+): FeatureId<CircleFeature<XY>> = circle(centerCoordinates.toCoordinates(), zoomRange, size, color, id = id)
-    id, SchemeCircleFeature(centerCoordinates.toCoordinates(), scaleRange, size, color)
-)
 
-fun SchemeFeaturesState.draw(
+fun FeaturesState<XY>.draw(
     position: Pair<Number, Number>,
-    scaleRange: FloatRange = defaultScaleRange,
+    zoomRange: FloatRange = Feature.defaultZoomRange,
-    id: FeatureId? = null,
+    id: String? = null,
-    drawFeature: DrawScope.() -> Unit,
+    draw: DrawScope.() -> Unit,
-) = addFeature(id, SchemeDrawFeature(position.toCoordinates(), scaleRange, drawFeature))
+): FeatureId<DrawFeature<XY>> = draw(position.toCoordinates(), zoomRange = zoomRange, id = id, draw = draw)
 
-fun SchemeFeaturesState.line(
+fun FeaturesState<XY>.line(
-    aCoordinates: SchemeCoordinates,
-    bCoordinates: SchemeCoordinates,
-    scaleRange: FloatRange = defaultScaleRange,
-    color: Color = Color.Red,
-    id: FeatureId? = null,
-): FeatureId = addFeature(
-    id,
-    SchemeLineFeature(aCoordinates, bCoordinates, scaleRange, color)
-)
-
-fun SchemeFeaturesState.line(
     aCoordinates: Pair<Number, Number>,
     bCoordinates: Pair<Number, Number>,
-    scaleRange: FloatRange = defaultScaleRange,
+    scaleRange: FloatRange = Feature.defaultZoomRange,
     color: Color = Color.Red,
-    id: FeatureId? = null,
+    id: String? = null,
-) = line(aCoordinates.toCoordinates(), bCoordinates.toCoordinates(), scaleRange, color, id)
+): FeatureId<LineFeature<XY>> = line(aCoordinates.toCoordinates(), bCoordinates.toCoordinates(), scaleRange, color, id)
 
-public fun SchemeFeaturesState.arc(
-    oval: SchemeRectangle,
-    startAngle: Float,
-    arcLength: Float,
-    scaleRange: FloatRange = defaultScaleRange,
-    color: Color = Color.Red,
-    id: FeatureId? = null,
-): FeatureId = addFeature(
-    id,
-    SchemeArcFeature(oval, startAngle, arcLength, scaleRange, color)
-)
 
-public fun SchemeFeaturesState.arc(
+public fun FeaturesState<XY>.arc(
     center: Pair<Double, Double>,
     radius: Float,
     startAngle: Float,
     arcLength: Float,
-    scaleRange: FloatRange = defaultScaleRange,
+    zoomRange: FloatRange = Feature.defaultZoomRange,
     color: Color = Color.Red,
-    id: FeatureId? = null,
+    id: String? = null,
-): FeatureId = addFeature(
+): FeatureId<ArcFeature<XY>> = arc(
-    id,
+    oval = XYCoordinateSpace.Rectangle(center.toCoordinates(), radius, radius),
-    SchemeArcFeature(
+    startAngle = startAngle,
-        oval = SchemeRectangle.square(center.toCoordinates(), radius, radius),
+    arcLength = arcLength,
-        startAngle = startAngle,
+    zoomRange = zoomRange,
-        arcLength = arcLength,
+    color = color
-        scaleRange = scaleRange,
-        color = color
-    )
 )
 
-fun SchemeFeaturesState.text(
+fun FeaturesState<XY>.image(
-    position: SchemeCoordinates,
-    text: String,
-    scaleRange: FloatRange = defaultScaleRange,
-    color: Color = Color.Red,
-    id: FeatureId? = null,
-) = addFeature(id, SchemeTextFeature(position, text, scaleRange, color))
-
-fun SchemeFeaturesState.text(
-    position: Pair<Number, Number>,
-    text: String,
-    scaleRange: FloatRange = defaultScaleRange,
-    color: Color = Color.Red,
-    id: FeatureId? = null,
-) = addFeature(id, SchemeTextFeature(position.toCoordinates(), text, scaleRange, color))
-
-fun SchemeFeaturesState.image(
     position: Pair<Number, Number>,
     image: ImageVector,
-    size: DpSize = DpSize(20.dp, 20.dp),
+    size: DpSize = DpSize(image.defaultWidth, image.defaultHeight),
-    scaleRange: FloatRange = defaultScaleRange,
+    zoomRange: FloatRange = Feature.defaultZoomRange,
-    id: FeatureId? = null,
+    id: String? = null,
-) = addFeature(id, SchemeImageFeature(position.toCoordinates(), image, size, scaleRange))
+): FeatureId<VectorImageFeature<XY>> =
+    image(position.toCoordinates(), image, size = size, zoomRange = zoomRange, id = id)
+
+fun FeaturesState<XY>.text(
+    position: Pair<Number, Number>,
+    text: String,
+    zoomRange: FloatRange = Feature.defaultZoomRange,
+    color: Color = Color.Red,
+    id: String? = null,
+): FeatureId<TextFeature<XY>> = text(position.toCoordinates(), text, zoomRange, color, id = id)
 
-fun SchemeFeaturesState.group(
-    scaleRange: FloatRange = defaultScaleRange,
-    id: FeatureId? = null,
-    builder: SchemeFeaturesState.() -> Unit,
-): FeatureId {
-    val groupBuilder = SchemeFeaturesState.build(builder)
-    val feature = SchemeFeatureGroup(groupBuilder.features(), scaleRange)
-    return addFeature(id, feature)
-}

maps-kt-scheme/src/commonMain/kotlin/center/sciprog/maps/scheme/SchemeViewPoint.kt

@@ -1,23 +0,0 @@
-package center.sciprog.maps.scheme
-
-import kotlin.math.pow
-
-data class SchemeViewPoint(val focus: SchemeCoordinates, val scale: Float = 1f)
-
-fun SchemeViewPoint.move(deltaX: Float, deltaY: Float): SchemeViewPoint {
-    return copy(focus = SchemeCoordinates(focus.x + deltaX, focus.y + deltaY))
-}
-
-fun SchemeViewPoint.zoom(
-    zoom: Float,
-    invariant: SchemeCoordinates = focus,
-): SchemeViewPoint = if (invariant == focus) {
-    copy(scale = scale * 2f.pow(zoom))
-} else {
-    val difScale =  (1 - 2f.pow(-zoom))
-    val newCenter = SchemeCoordinates(
-        focus.x + (invariant.x - focus.x) * difScale,
-        focus.y + (invariant.y - focus.y) * difScale
-    )
-    SchemeViewPoint(newCenter, scale * 2f.pow(zoom))
-}

maps-kt-scheme/src/commonMain/kotlin/center/sciprog/maps/scheme/XY.kt

@@ -0,0 +1,64 @@
+package center.sciprog.maps.scheme
+
+import androidx.compose.ui.unit.DpSize
+import androidx.compose.ui.unit.dp
+import center.sciprog.maps.features.CoordinateSpace
+import center.sciprog.maps.features.Rectangle
+import center.sciprog.maps.features.ViewPoint
+import kotlin.math.abs
+import kotlin.math.max
+import kotlin.math.min
+
+data class XY(val x: Float, val y: Float)
+
+internal data class XYRectangle(
+    override val a: XY,
+    override val b: XY,
+) : Rectangle<XY> {
+
+    override fun contains(point: XY): Boolean = point.x in a.x..b.x && point.y in a.y..b.y
+
+//    companion object {
+//        fun square(center: XY, height: Float, width: Float): XYRectangle = XYRectangle(
+//            XY(center.x - width / 2, center.y + height / 2),
+//            XY(center.x + width / 2, center.y - height / 2),
+//        )
+//    }
+}
+
+val Rectangle<XY>.top get() = max(a.y, b.y)
+val Rectangle<XY>.bottom get() = min(a.y, b.y)
+
+val Rectangle<XY>.right get() = max(a.x, b.x)
+val Rectangle<XY>.left get() = min(a.x, b.x)
+
+val Rectangle<XY>.width: Float get() = abs(a.x - b.x)
+val Rectangle<XY>.height: Float get() = abs(a.y - b.y)
+
+val Rectangle<XY>.center get() = XY((a.x + b.x) / 2, (a.y + b.y) / 2)
+
+public val Rectangle<XY>.leftTop: XY get() = XY(left, top)
+public val Rectangle<XY>.rightBottom: XY get() = XY(right, bottom)
+
+internal val defaultCanvasSize = DpSize(512.dp, 512.dp)
+
+data class XYViewPoint(
+    override val focus: XY,
+    override val zoom: Float = 1f,
+) : ViewPoint<XY>
+
+public fun CoordinateSpace<XY>.Rectangle(
+    center: XY,
+    height: Float,
+    width: Float,
+): Rectangle<XY> {
+    val a = XY(
+        center.x - (width / 2),
+        center.y - (height / 2)
+    )
+    val b = XY(
+        center.x + (width / 2),
+        center.y + (height / 2)
+    )
+    return XYRectangle(a, b)
+}

maps-kt-scheme/src/commonMain/kotlin/center/sciprog/maps/scheme/XYCoordinateSpace.kt

@@ -0,0 +1,64 @@
+package center.sciprog.maps.scheme
+
+import androidx.compose.ui.unit.DpSize
+import center.sciprog.maps.features.CoordinateSpace
+import center.sciprog.maps.features.Rectangle
+import center.sciprog.maps.features.ViewPoint
+import kotlin.math.pow
+
+object XYCoordinateSpace : CoordinateSpace<XY> {
+    override fun Rectangle(first: XY, second: XY): Rectangle<XY> =
+        XYRectangle(first, second)
+
+    override fun Rectangle(center: XY, zoom: Float, size: DpSize): Rectangle<XY> =
+        Rectangle(center, (size.width.value / zoom), (size.height.value / zoom))
+
+    override fun ViewPoint(center: XY, zoom: Float): ViewPoint<XY> =
+        XYViewPoint(center, zoom)
+
+    override fun ViewPoint<XY>.moveBy(delta: XY): ViewPoint<XY> =
+        XYViewPoint(XY(focus.x + delta.x, focus.y + delta.y))
+
+    override fun ViewPoint<XY>.zoomBy(
+        zoomDelta: Float,
+        invariant: XY,
+    ): ViewPoint<XY> = if (invariant == focus) {
+        XYViewPoint(focus, zoom = zoom * 2f.pow(zoomDelta))
+    } else {
+        val difScale = (1 - 2f.pow(-zoomDelta))
+        val newCenter = XY(
+            focus.x + (invariant.x - focus.x) * difScale,
+            focus.y + (invariant.y - focus.y) * difScale
+        )
+        XYViewPoint(newCenter, zoom * 2f.pow(zoomDelta))
+    }
+
+    override fun Rectangle<XY>.withCenter(center: XY): Rectangle<XY> =
+        Rectangle(center, width, height)
+
+    override fun Collection<Rectangle<XY>>.wrapRectangles(): Rectangle<XY>? {
+        if (isEmpty()) return null
+        val minX = minOf { it.left }
+        val maxX = maxOf { it.right }
+
+        val minY = minOf { it.bottom }
+        val maxY = maxOf { it.top }
+        return XYRectangle(
+            XY(minX, minY),
+            XY(maxX, maxY)
+        )
+    }
+
+    override fun Collection<XY>.wrapPoints(): Rectangle<XY>? {
+        if (isEmpty()) return null
+        val minX = minOf { it.x }
+        val maxX = maxOf { it.x }
+
+        val minY = minOf { it.y }
+        val maxY = maxOf { it.y }
+        return XYRectangle(
+            XY(minX, minY),
+            XY(maxX, maxY)
+        )
+    }
+}

maps-kt-scheme/src/commonMain/kotlin/center/sciprog/maps/scheme/XYViewState.kt

@@ -0,0 +1,45 @@
+package center.sciprog.maps.scheme
+
+import androidx.compose.ui.unit.*
+import center.sciprog.maps.features.*
+import kotlin.math.min
+
+class XYViewState(
+    config: ViewConfig<XY>,
+    canvasSize: DpSize,
+    viewPoint: ViewPoint<XY>,
+) : CoordinateViewState<XY>(config, canvasSize, viewPoint) {
+    override val space: CoordinateSpace<XY>
+        get() = XYCoordinateSpace
+
+    override fun DpOffset.toCoordinates(): XY = XY(
+        (x - canvasSize.width / 2).value / viewPoint.zoom + viewPoint.focus.x,
+        (canvasSize.height / 2 - y).value / viewPoint.zoom + viewPoint.focus.y
+    )
+
+    override fun XY.toDpOffset(): DpOffset = DpOffset(
+        (canvasSize.width / 2 + (x.dp - viewPoint.focus.x.dp) * viewPoint.zoom),
+        (canvasSize.height / 2 + (viewPoint.focus.y.dp - y.dp) * viewPoint.zoom)
+    )
+
+    override fun viewPointFor(rectangle: Rectangle<XY>): ViewPoint<XY> {
+        val scale = min(
+            canvasSize.width.value / rectangle.width,
+            canvasSize.height.value / rectangle.height
+        )
+
+        return XYViewPoint(rectangle.center, scale)
+    }
+
+    override fun ViewPoint<XY>.moveBy(x: Dp, y: Dp): ViewPoint<XY> {
+        val newCoordinates = XY(focus.x + x.value / zoom, focus.y + y.value / zoom)
+        return XYViewPoint(newCoordinates, zoom)
+    }
+
+    override fun Rectangle<XY>.toDpRect(): DpRect {
+        val topLeft = leftTop.toDpOffset()
+        val bottomRight = rightBottom.toDpOffset()
+        return DpRect(topLeft.x, topLeft.y, bottomRight.x, bottomRight.y)
+    }
+
+}

maps-kt-scheme/src/jvmMain/kotlin/center/sciprog/maps/scheme/SchemeView.kt

@@ -1,296 +1,120 @@
 package center.sciprog.maps.scheme
 
 import androidx.compose.foundation.Canvas
-import androidx.compose.foundation.gestures.drag
-import androidx.compose.foundation.gestures.forEachGesture
 import androidx.compose.foundation.layout.fillMaxSize
-import androidx.compose.runtime.*
+import androidx.compose.runtime.Composable
-import androidx.compose.ui.ExperimentalComposeUiApi
+import androidx.compose.runtime.key
+import androidx.compose.runtime.remember
 import androidx.compose.ui.Modifier
-import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.graphics.Color
-import androidx.compose.ui.geometry.Rect
+import androidx.compose.ui.graphics.PathEffect
-import androidx.compose.ui.geometry.Size
+import androidx.compose.ui.graphics.drawscope.Stroke
-import androidx.compose.ui.graphics.*
+import androidx.compose.ui.graphics.drawscope.clipRect
-import androidx.compose.ui.graphics.drawscope.*
+import androidx.compose.ui.graphics.painter.Painter
-import androidx.compose.ui.input.pointer.*
-import androidx.compose.ui.unit.DpOffset
 import androidx.compose.ui.unit.DpSize
-import androidx.compose.ui.unit.dp
+import center.sciprog.maps.compose.mapControls
+import center.sciprog.maps.features.*
 import mu.KotlinLogging
-import org.jetbrains.skia.Font
-import org.jetbrains.skia.Paint
-import kotlin.math.PI
-import kotlin.math.abs
-import kotlin.math.max
 import kotlin.math.min
 
 
-internal fun Color.toSkiaPaint(): Paint = Paint().apply {
-    isAntiAlias = true
-    color = toArgb()
-}
-
-private fun IntRange.intersect(other: IntRange) = max(first, other.first)..min(last, other.last)
-
 private val logger = KotlinLogging.logger("SchemeView")
 
-data class SchemeViewConfig(
-    val zoomSpeed: Float = 1f / 3f,
-    val onClick: SchemeViewPoint.() -> Unit = {},
-    val onViewChange: SchemeViewPoint.() -> Unit = {},
-    val onSelect: (SchemeRectangle) -> Unit = {},
-    val zoomOnSelect: Boolean = true,
-)
-
 @Composable
 public fun SchemeView(
-    initialViewPoint: SchemeViewPoint,
+    initialViewPoint: ViewPoint<XY>,
-    featuresState: SchemeFeaturesState,
+    featuresState: FeaturesState<XY>,
-    config: SchemeViewConfig = SchemeViewConfig(),
+    config: ViewConfig<XY>,
     modifier: Modifier = Modifier.fillMaxSize(),
 ) = key(initialViewPoint) {
 
-    var canvasSize by remember { mutableStateOf(defaultCanvasSize) }
+    val state = remember {
-
+        XYViewState(
-    var viewPoint by remember { mutableStateOf(initialViewPoint) }
+            config,
-
+            defaultCanvasSize,
-
+            initialViewPoint,
-    fun setViewPoint(newViewPoint: SchemeViewPoint) {
-        config.onViewChange(newViewPoint)
-        viewPoint = newViewPoint
-    }
-
-
-    fun DpOffset.toCoordinates(): SchemeCoordinates = SchemeCoordinates(
-        (x - canvasSize.width / 2).value / viewPoint.scale + viewPoint.focus.x,
-        (canvasSize.height / 2 - y).value / viewPoint.scale + viewPoint.focus.y
-    )
-
-    // 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)
-                                    )
-                                }
-                            }
-                            selectRect?.let { rect ->
-                                //Use selection override if it is defined
-                                val box = SchemeRectangle(
-                                    rect.topLeft.toDpOffset().toCoordinates(),
-                                    rect.bottomRight.toDpOffset().toCoordinates()
-                                )
-                                config.onSelect(box)
-                                if (config.zoomOnSelect) {
-                                    val newScale = min(
-                                        canvasSize.width.value / box.width,
-                                        canvasSize.height.value / box.height
-                                    )
-
-                                    val newViewPoint = SchemeViewPoint(box.center, newScale)
-
-                                    setViewPoint(newViewPoint)
-                                }
-                                selectRect = null
-                            }
-                        } else {
-                            val dragStart = change.position
-                            val dpPos = DpOffset(dragStart.x.toDp(), dragStart.y.toDp())
-                            config.onClick(SchemeViewPoint(dpPos.toCoordinates(), viewPoint.scale))
-                            drag(change.id) { dragChange ->
-                                val dragAmount = dragChange.position - dragChange.previousPosition
-                                val newViewPoint = viewPoint.move(
-                                    -dragAmount.x.toDp().value / viewPoint.scale,
-                                    dragAmount.y.toDp().value / viewPoint.scale
-                                )
-                                setViewPoint(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()).toCoordinates()
-        val newViewPoint = viewPoint.zoom(-change.scrollDelta.y * config.zoomSpeed, invariant)
-        setViewPoint(newViewPoint)
-    }.fillMaxSize()
-
-    val painterCache = key(featuresState) {
-        featuresState.features().values.filterIsInstance<PainterFeature>().associateWith { it.painter() }
-    }
-
-    Canvas(canvasModifier) {
-        fun SchemeCoordinates.toOffset(): Offset = Offset(
-            (canvasSize.width / 2 + (x.dp - viewPoint.focus.x.dp) * viewPoint.scale).toPx(),
-            (canvasSize.height / 2 + (viewPoint.focus.y.dp - y.dp) * viewPoint.scale).toPx()
         )
+    }
+    with(state) {
+        val painterCache: Map<PainterFeature<XY>, Painter> = key(featuresState) {
+            featuresState.features.values.filterIsInstance<PainterFeature<XY>>().associateWith { it.painter() }
+        }
 
+        Canvas(modifier = modifier.mapControls(state).fillMaxSize()) {
 
-        fun DrawScope.drawFeature(scale: Float, feature: SchemeFeature) {
+            if (canvasSize != size.toDpSize()) {
-            when (feature) {
+                canvasSize = size.toDpSize()
-                is SchemeBackgroundFeature -> {
+                logger.debug { "Recalculate canvas. Size: $size" }
-                    val offset = SchemeCoordinates(feature.rectangle.left, feature.rectangle.top).toOffset()
+            }
 
-                    val backgroundSize = DpSize(
+            clipRect {
-                        (feature.rectangle.width * scale).dp,
+                featuresState.features.values.filterIsInstance<ScalableImageFeature<XY>>().forEach { background ->
-                        (feature.rectangle.height * scale).dp
+                    drawFeature(state, painterCache, background)
-                    ).toSize()
-
-                    translate(offset.x, offset.y) {
-                        with(painterCache[feature]!!) {
-                            draw(backgroundSize)
-                        }
-                    }
                 }
-
+                featuresState.features.values.filter {
-                is SchemeFeatureSelector -> drawFeature(scale, feature.selector(scale))
+                    it !is ScalableImageFeature && viewPoint.zoom in it.zoomRange
-                is SchemeCircleFeature -> drawCircle(
+                }.forEach { feature ->
-                    feature.color,
+                    drawFeature(state, painterCache, feature)
-                    feature.size,
+                }
-                    center = feature.center.toOffset()
+            }
-                )
+            selectRect?.let { dpRect ->
-
+                val rect = dpRect.toRect()
-                is SchemeLineFeature -> drawLine(
+                drawRect(
-                    feature.color,
+                    color = Color.Blue,
-                    feature.a.toOffset(),
+                    topLeft = rect.topLeft,
-                    feature.b.toOffset(),
+                    size = rect.size,
-                )
+                    alpha = 0.5f,
-
+                    style = Stroke(
-                is SchemeArcFeature -> {
+                        width = 2f,
-                    val topLeft = feature.oval.leftTop.toOffset()
+                        pathEffect = PathEffect.dashPathEffect(floatArrayOf(10f, 10f), 0f)
-                    val bottomRight = feature.oval.rightBottom.toOffset()
-
-                    val size = Size(abs(topLeft.x - bottomRight.x), abs(topLeft.y - bottomRight.y))
-
-                    drawArc(
-                        color = feature.color,
-                        startAngle = (feature.startAngle * 180 / PI).toFloat(),
-                        sweepAngle = (feature.arcLength * 180 / PI).toFloat(),
-                        useCenter = false,
-                        topLeft = topLeft,
-                        size = size,
-                        style = Stroke()
                     )
-                }
-
-                is SchemeBitmapFeature -> drawImage(feature.image, feature.position.toOffset())
-                is SchemeImageFeature -> {
-                    val offset = feature.position.toOffset()
-                    val imageSize = feature.size.toSize()
-                    translate(offset.x - imageSize.width / 2, offset.y - imageSize.height / 2) {
-                        with(painterCache[feature]!!) {
-                            draw(imageSize)
-                        }
-                    }
-                }
-
-                is SchemeTextFeature -> drawIntoCanvas { canvas ->
-                    val offset = feature.position.toOffset()
-                    canvas.nativeCanvas.drawString(
-                        feature.text,
-                        offset.x + 5,
-                        offset.y - 5,
-                        Font().apply { size = 16f },
-                        feature.color.toSkiaPaint()
-                    )
-                }
-
-                is SchemeDrawFeature -> {
-                    val offset = feature.position.toOffset()
-                    translate(offset.x, offset.y) {
-                        feature.drawFeature(this)
-                    }
-                }
-
-                is SchemeFeatureGroup -> {
-                    feature.children.values.forEach {
-                        drawFeature(scale, it)
-                    }
-                }
-            }
-        }
-
-        if (canvasSize != size.toDpSize()) {
-            canvasSize = size.toDpSize()
-            logger.debug { "Recalculate canvas. Size: $size" }
-        }
-        clipRect {
-            featuresState.features().values.filterIsInstance<SchemeBackgroundFeature>().forEach { background ->
-                drawFeature(viewPoint.scale, background)
-            }
-            featuresState.features().values.filter {
-                it !is SchemeBackgroundFeature && viewPoint.scale in it.scaleRange
-            }.forEach { feature ->
-                drawFeature(viewPoint.scale, 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)
                 )
-            )
+            }
         }
     }
+
 }
 
+public fun Rectangle<XY>.computeViewPoint(
+    canvasSize: DpSize = defaultCanvasSize,
+): ViewPoint<XY> {
+    val zoom = min(
+        canvasSize.width.value / width,
+        canvasSize.height.value / height
+    )
+
+    return XYViewPoint(center, zoom.toFloat())
+}
 
 /**
  * A builder for a Scheme with static features.
  */
 @Composable
 public fun SchemeView(
-    initialViewPoint: SchemeViewPoint? = null,
+    initialViewPoint: ViewPoint<XY>? = null,
-    initialRectangle: SchemeRectangle? = null,
+    initialRectangle: Rectangle<XY>? = null,
-    featureMap: Map<FeatureId, SchemeFeature>,
+    featureMap: Map<FeatureId<*>, Feature<XY>>,
-    config: SchemeViewConfig = SchemeViewConfig(),
+    config: ViewConfig<XY> = ViewConfig(),
     modifier: Modifier = Modifier.fillMaxSize(),
 ) {
     val featuresState = key(featureMap) {
-        SchemeFeaturesState.build {
+        FeaturesState.build(XYCoordinateSpace) {
-            featureMap.forEach(::addFeature)
+            featureMap.forEach { feature(it.key.id, it.value) }
         }
     }
 
-    val viewPointOverride: SchemeViewPoint = remember(initialViewPoint, initialRectangle) {
+    val viewPointOverride: ViewPoint<XY> = remember(initialViewPoint, initialRectangle) {
         initialViewPoint
             ?: initialRectangle?.computeViewPoint()
-            ?: featureMap.values.computeBoundingBox(1f)?.computeViewPoint()
+            ?: featureMap.values.computeBoundingBox(XYCoordinateSpace, 1f)?.computeViewPoint()
-            ?: SchemeViewPoint(SchemeCoordinates(0f, 0f))
+            ?: XYViewPoint(XY(0f, 0f), 1f)
     }
 
     SchemeView(viewPointOverride, featuresState, config, modifier)
 }
 
 /**
- * Draw a map using convenient parameters. If neither [initialViewPoint], noe [initialRectangle] is defined,
+ * Draw a scheme using convenient parameters. If neither [initialViewPoint], noe [initialRectangle] is defined,
  * use map features to infer view region.
  * @param initialViewPoint The view point of the map using center and zoom. Is used if provided
  * @param initialRectangle The rectangle to be used for view point computation. Used if [initialViewPoint] is not defined.
@@ -298,45 +122,119 @@ public fun SchemeView(
  */
 @Composable
 public fun SchemeView(
-    initialViewPoint: SchemeViewPoint? = null,
+    initialViewPoint: ViewPoint<XY>? = null,
-    initialRectangle: SchemeRectangle? = null,
+    initialRectangle: Rectangle<XY>? = null,
-    config: SchemeViewConfig = SchemeViewConfig(),
+    config: ViewConfig<XY> = ViewConfig(),
     modifier: Modifier = Modifier.fillMaxSize(),
-    buildFeatures: SchemeFeaturesState.() -> Unit = {},
+    buildFeatures: FeaturesState<XY>.() -> Unit = {},
 ) {
-    val featureState = SchemeFeaturesState.remember(buildFeatures)
+    val featureState = FeaturesState.remember(XYCoordinateSpace, buildFeatures)
 
-    val features = featureState.features()
+    val viewPointOverride: ViewPoint<XY> = remember(initialViewPoint, initialRectangle) {
-
-    val viewPointOverride: SchemeViewPoint = remember(initialViewPoint, initialRectangle) {
         initialViewPoint
             ?: initialRectangle?.computeViewPoint()
-            ?: features.values.computeBoundingBox(1f)?.computeViewPoint()
+            ?: featureState.features.values.computeBoundingBox(XYCoordinateSpace, 1f)?.computeViewPoint()
-            ?: SchemeViewPoint(SchemeCoordinates(0f, 0f))
+            ?: XYViewPoint(XY(0f, 0f), 1f)
     }
 
-//    val featureDrag = DragHandle.withPrimaryButton { _, start, end ->
+    val featureDrag: DragHandle<XY> =
-//        val zoom = start.zoom
+        DragHandle.withPrimaryButton { event, start: ViewPoint<XY>, end: ViewPoint<XY> ->
-//        featureState.findAllWithAttribute(DraggableAttribute) { it }.forEach { id ->
+            featureState.forEachWithAttribute(DraggableAttribute) { _, handle ->
-//            val feature = features[id] as? DraggableMapFeature ?: return@forEach
+                //TODO add safety
-//            val boundingBox = feature.getBoundingBox(zoom) ?: return@forEach
+                handle as DragHandle<XY>
-//            if (start.focus in boundingBox) {
+                if (!handle.handle(event, start, end)) return@withPrimaryButton false
-//                featureState.addFeature(id, feature.withCoordinates(end.focus))
+            }
-//                return@withPrimaryButton false
+            true
-//            }
+        }
-//        }
+
-//        return@withPrimaryButton true
+
-//    }
+    val newConfig = config.copy(
-//
+        dragHandle = DragHandle.combine(featureDrag, config.dragHandle)
-//
+    )
-//    val newConfig = config.copy(
-//        dragHandle = DragHandle.combine(featureDrag, config.dragHandle)
-//    )
 
     SchemeView(
         initialViewPoint = viewPointOverride,
         featuresState = featureState,
-        config = config,
+        config = newConfig,
         modifier = modifier,
     )
 }
+
+///**
+// * A builder for a Scheme with static features.
+// */
+//@Composable
+//public fun SchemeView(
+//    initialViewPoint: XYViewPoint? = null,
+//    initialRectangle: XYRectangle? = null,
+//    featureMap: Map<FeatureId<*>,>,
+//    config: SchemeViewConfig = SchemeViewConfig(),
+//    modifier: Modifier = Modifier.fillMaxSize(),
+//) {
+//    val featuresState = key(featureMap) {
+//        SchemeFeaturesState.build {
+//            featureMap.forEach(::addFeature)
+//        }
+//    }
+//
+//    val viewPointOverride: XYViewPoint = remember(initialViewPoint, initialRectangle) {
+//        initialViewPoint
+//            ?: initialRectangle?.computeViewPoint()
+//            ?: featureMap.values.computeBoundingBox(1f)?.computeViewPoint()
+//            ?: XYViewPoint(XY(0f, 0f))
+//    }
+//
+//    SchemeView(viewPointOverride, featuresState, config, modifier)
+//}
+//
+///**
+// * Draw a map using convenient parameters. If neither [initialViewPoint], noe [initialRectangle] is defined,
+// * use map features to infer view region.
+// * @param initialViewPoint The view point of the map using center and zoom. Is used if provided
+// * @param initialRectangle The rectangle to be used for view point computation. Used if [initialViewPoint] is not defined.
+// * @param buildFeatures - a builder for features
+// */
+//@Composable
+//public fun SchemeView(
+//    initialViewPoint: XYViewPoint? = null,
+//    initialRectangle: Rectangle<XY>? = null,
+//    config: ViewConfig<XY> = ViewConfig(),
+//    modifier: Modifier = Modifier.fillMaxSize(),
+//    buildFeatures: FeaturesState<XY>.() -> Unit = {},
+//) {
+//    val featureState = FeaturesState.remember(XYCoordinateSpace, buildFeatures)
+//
+//    val features = featureState.features
+//
+//    val viewPointOverride: XYViewPoint = remember(initialViewPoint, initialRectangle) {
+//        initialViewPoint
+//            ?: initialRectangle?.computeViewPoint()
+//            ?: features.values.computeBoundingBox(1f)?.computeViewPoint()
+//            ?: XYViewPoint(XY(0f, 0f))
+//    }
+//
+////    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 = config.copy(
+////        dragHandle = DragHandle.combine(featureDrag, config.dragHandle)
+////    )
+//
+//    SchemeView(
+//        initialViewPoint = viewPointOverride,
+//        featuresState = featureState,
+//        config = config,
+//        modifier = modifier,
+//    )
+//}

maps-kt-scheme/src/jvmMain/kotlin/center/sciprog/maps/svg/exportToSvg.kt

@@ -7,6 +7,7 @@ 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.painter.Painter
+import center.sciprog.maps.features.*
 import center.sciprog.maps.scheme.*
 import org.jfree.svg.SVGGraphics2D
 import org.jfree.svg.SVGUtils
@@ -15,34 +16,34 @@ import kotlin.math.PI
 import kotlin.math.abs
 
 
-class FeatureStateSnapshot(
+class FeatureStateSnapshot<T : Any>(
-    val features: Map<FeatureId, SchemeFeature>,
+    val features: Map<FeatureId<*>, Feature<T>>,
-    val painterCache: Map<PainterFeature, Painter>,
+    val painterCache: Map<PainterFeature<T>, Painter>,
 )
 
 @Composable
-fun SchemeFeaturesState.snapshot(): FeatureStateSnapshot =
+fun <T: Any> FeaturesState<T>.snapshot(): FeatureStateSnapshot<T> = FeatureStateSnapshot(
-    FeatureStateSnapshot(
+    features,
-        features(),
+    features.values.filterIsInstance<PainterFeature<T>>().associateWith { it.painter() }
-        features().values.filterIsInstance<PainterFeature>().associateWith { it.painter() })
+)
 
-fun FeatureStateSnapshot.generateSvg(
+fun FeatureStateSnapshot<XY>.generateSvg(
-    viewPoint: SchemeViewPoint,
+    viewPoint: ViewPoint<XY>,
     width: Double,
     height: Double,
-    id: String? = null
+    id: String? = null,
-): String{
+): String {
 
-    fun SchemeCoordinates.toOffset(): Offset = Offset(
+    fun XY.toOffset(): Offset = Offset(
-        (width / 2 + (x - viewPoint.focus.x) * viewPoint.scale).toFloat(),
+        (width / 2 + (x - viewPoint.focus.x) * viewPoint.zoom).toFloat(),
-        (height / 2 + (viewPoint.focus.y - y) * viewPoint.scale).toFloat()
+        (height / 2 + (viewPoint.focus.y - y) * viewPoint.zoom).toFloat()
     )
 
 
-    fun SvgDrawScope.drawFeature(scale: Float, feature: SchemeFeature) {
+    fun SvgDrawScope.drawFeature(scale: Float, feature: Feature<XY>) {
         when (feature) {
-            is SchemeBackgroundFeature -> {
+            is ScalableImageFeature -> {
-                val offset = SchemeCoordinates(feature.rectangle.left, feature.rectangle.top).toOffset()
+                val offset = XY(feature.rectangle.left, feature.rectangle.top).toOffset()
                 val backgroundSize = Size(
                     (feature.rectangle.width * scale),
                     (feature.rectangle.height * scale)
@@ -55,15 +56,17 @@ fun FeatureStateSnapshot.generateSvg(
                 }
             }
 
-            is SchemeFeatureSelector -> drawFeature(scale, feature.selector(scale))
+            is FeatureSelector -> drawFeature(scale, feature.selector(scale))
-            is SchemeCircleFeature -> drawCircle(
+
+            is CircleFeature -> drawCircle(
                 feature.color,
-                feature.size,
+                feature.size.toPx(),
                 center = feature.center.toOffset()
             )
 
-            is SchemeLineFeature -> drawLine(feature.color, feature.a.toOffset(), feature.b.toOffset())
+            is LineFeature -> drawLine(feature.color, feature.a.toOffset(), feature.b.toOffset())
-            is SchemeArcFeature -> {
+
+            is ArcFeature -> {
                 val topLeft = feature.oval.leftTop.toOffset()
                 val bottomRight = feature.oval.rightBottom.toOffset()
 
@@ -80,9 +83,9 @@ fun FeatureStateSnapshot.generateSvg(
                 )
             }
 
-            is SchemeBitmapFeature -> drawImage(feature.image, feature.position.toOffset())
+            is BitmapImageFeature -> drawImage(feature.image, feature.position.toOffset())
 
-            is SchemeImageFeature -> {
+            is VectorImageFeature -> {
                 val offset = feature.position.toOffset()
                 val imageSize = feature.size.toSize()
                 translate(offset.x - imageSize.width / 2, offset.y - imageSize.height / 2) {
@@ -92,7 +95,7 @@ fun FeatureStateSnapshot.generateSvg(
                 }
             }
 
-            is SchemeTextFeature -> drawIntoCanvas { canvas ->
+            is TextFeature -> drawIntoCanvas { canvas ->
                 val offset = feature.position.toOffset()
                 drawText(
                     feature.text,
@@ -103,14 +106,14 @@ fun FeatureStateSnapshot.generateSvg(
                 )
             }
 
-            is SchemeDrawFeature -> {
+            is DrawFeature -> {
                 val offset = feature.position.toOffset()
                 translate(offset.x, offset.y) {
                     feature.drawFeature(this)
                 }
             }
 
-            is SchemeFeatureGroup -> {
+            is FeatureGroup -> {
                 feature.children.values.forEach {
                     drawFeature(scale, it)
                 }
@@ -122,20 +125,20 @@ fun FeatureStateSnapshot.generateSvg(
     val svgScope = SvgDrawScope(svgGraphics2D, Size(width.toFloat(), height.toFloat()))
 
     svgScope.apply {
-        features.values.filterIsInstance<SchemeBackgroundFeature>().forEach { background ->
+        features.values.filterIsInstance<ScalableImageFeature<XY>>().forEach { background ->
-            drawFeature(viewPoint.scale, background)
+            drawFeature(viewPoint.zoom, background)
         }
         features.values.filter {
-            it !is SchemeBackgroundFeature && viewPoint.scale in it.scaleRange
+            it !is ScalableImageFeature && viewPoint.zoom in it.zoomRange
         }.forEach { feature ->
-            drawFeature(viewPoint.scale, feature)
+            drawFeature(viewPoint.zoom, feature)
         }
     }
     return svgGraphics2D.getSVGElement(id)
 }
 
-fun FeatureStateSnapshot.exportToSvg(
+fun FeatureStateSnapshot<XY>.exportToSvg(
-    viewPoint: SchemeViewPoint,
+    viewPoint: ViewPoint<XY>,
     width: Double,
     height: Double,
     path: java.nio.file.Path,