feat(geobase): populated and unpopulated methods for Bounded #197

dart/geobase/CHANGELOG.md

@@ -4,6 +4,7 @@ NOTE: Version 0.6.0 currently [under development](https://github.com/navibyte/ge
 
 🧩 Features:
 * [Add copyWith (and map) methods to coordinate, meta, feature and geometry classes #189](https://github.com/navibyte/geospatial/issues/189)
+* [Populating and unpopulating bounds in geometries and feature objects #197](https://github.com/navibyte/geospatial/issues/197)
 
 ⚠️ Breaking changes:
 * [Allow a position stored as "Position" in Point, and a bounding box as "Box" in Geometry classes #192](https://github.com/navibyte/geospatial/issues/192)

dart/geobase/lib/src/vector_data/model/bounded/bounded.dart

@@ -53,6 +53,36 @@ abstract class Bounded {
   /// cannot be calculated (for example in the case of an empty geometry).
   Bounded bounded({bool recalculate = false});
 
+  /// Returns a bounded object of the same subtype as this with certain data
+  /// members populated.
+  ///
+  /// If nothing is populated then `this` is returned.
+  ///
+  /// If [onBounds] is true (as by default):
+  /// * The `bounds` in a returned bounded object is ensured to be populated
+  ///   (expect when cannot be calculated, for example in the case of an empty
+  ///   geometry).
+  /// * If [traverse] is true, then also bounding boxes of any child bounded
+  ///   objects are populated.
+  Bounded populated({
+    bool traverse = false,
+    bool onBounds = true,
+  });
+
+  /// Returns a bounded object of the same subtype as this with certain data
+  /// members unpopulated (or cleared).
+  ///
+  /// If nothing is unpopulated then `this` is returned.
+  ///
+  /// If [onBounds] is true (as by default):
+  /// * The `bounds` in a returned bounded object is ensured to be unpopulated.
+  /// * If [traverse] is true, then also bounding boxes of any child bounded
+  ///   objects are unpopulated.
+  Bounded unpopulated({
+    bool traverse = false,
+    bool onBounds = true,
+  });
+
   /// Returns a new bounded object with all geometries projected using
   /// [projection] and other properties left intact.
   ///

dart/geobase/lib/src/vector_data/model/feature/feature.dart

@@ -253,6 +253,55 @@ class Feature<T extends Geometry> extends FeatureObject {
     );
   }
 
+  @override
+  Feature populated({
+    bool traverse = false,
+    bool onBounds = true,
+  }) {
+    if (onBounds) {
+      // populate a geometry when traversing is asked
+      final geom = traverse
+          ? geometry?.populated(traverse: traverse, onBounds: onBounds)
+          : geometry;
+
+      // create a new feature if geometry changed or bounds was unpopulated
+      if (geom != geometry || (bounds == null && geom != null)) {
+        return Feature(
+          id: id,
+          geometry: geom,
+          properties: properties,
+          bounds: geom != null ? _buildBoundsFrom(geom) : null,
+          custom: custom,
+        );
+      }
+    }
+    return this;
+  }
+
+  @override
+  Feature unpopulated({
+    bool traverse = false,
+    bool onBounds = true,
+  }) {
+    if (onBounds) {
+      // unpopulate a geometry when traversing is asked
+      final geom = traverse
+          ? geometry?.unpopulated(traverse: traverse, onBounds: onBounds)
+          : geometry;
+
+      // create a new feature if geometry changed or bounds was populated
+      if (geom != geometry || bounds != null) {
+        return Feature(
+          id: id,
+          geometry: geom,
+          properties: properties,
+          custom: custom,
+        );
+      }
+    }
+    return this;
+  }
+
   @override
   Feature<T> project(Projection projection) {
     final projectedGeom = geometry?.project(projection) as T?;

dart/geobase/lib/src/vector_data/model/feature/feature_collection.dart

@@ -246,6 +246,62 @@ class FeatureCollection<E extends Feature> extends FeatureObject {
     );
   }
 
+  @override
+  FeatureCollection populated({
+    bool traverse = false,
+    bool onBounds = true,
+  }) {
+    if (onBounds) {
+      // populate features when traversing is asked
+      final coll = traverse && features.isNotEmpty
+          ? features
+              .map<E>(
+                (f) => f.populated(traverse: traverse, onBounds: onBounds) as E,
+              )
+              .toList(growable: false)
+          : features;
+
+      // create a new collection if features changed or bounds was unpopulated
+      if (coll != features || (bounds == null && coll.isNotEmpty)) {
+        return FeatureCollection<E>._(
+          coll,
+          coordType,
+          bounds: _buildBoundsFrom(coll, coordType),
+          custom: custom,
+        );
+      }
+    }
+    return this;
+  }
+
+  @override
+  FeatureCollection unpopulated({
+    bool traverse = false,
+    bool onBounds = true,
+  }) {
+    if (onBounds) {
+      // unpopulate features when traversing is asked
+      final coll = traverse && features.isNotEmpty
+          ? features
+              .map<E>(
+                (f) =>
+                    f.unpopulated(traverse: traverse, onBounds: onBounds) as E,
+              )
+              .toList(growable: false)
+          : features;
+
+      // create a new collection if features changed or bounds was populated
+      if (coll != features || bounds != null) {
+        return FeatureCollection<E>._(
+          coll,
+          coordType,
+          custom: custom,
+        );
+      }
+    }
+    return this;
+  }
+
   @override
   FeatureCollection<E> project(Projection projection) {
     final projected = features

dart/geobase/lib/src/vector_data/model/feature/feature_object.dart

@@ -6,6 +6,7 @@
 
 import 'dart:typed_data';
 
+import 'package:geobase/vector_data.dart';
 import 'package:meta/meta.dart';
 
 import '/src/coordinates/projection/projection.dart';
@@ -28,6 +29,18 @@ abstract class FeatureObject extends Bounded {
   const FeatureObject({super.bounds, Map<String, dynamic>? custom})
       : _custom = custom;
 
+  @override
+  FeatureObject populated({
+    bool traverse = false,
+    bool onBounds = true,
+  });
+
+  @override
+  FeatureObject unpopulated({
+    bool traverse = false,
+    bool onBounds = true,
+  });
+
   /// Returns a new feature obect with all geometries projected using
   /// [projection].
   ///

dart/geobase/lib/src/vector_data/model/geometry/geometry.dart

@@ -43,6 +43,18 @@ abstract class Geometry extends Bounded {
   /// * `GeometryCollection` has no geometries.
   bool get isEmpty;
 
+  @override
+  Geometry populated({
+    bool traverse = false,
+    bool onBounds = true,
+  });
+
+  @override
+  Geometry unpopulated({
+    bool traverse = false,
+    bool onBounds = true,
+  });
+
   /// Returns a new geometry projected using [projection].
   ///
   /// The returned geometry sub type must be the same as the type of this.

dart/geobase/lib/src/vector_data/model/geometry/geometry_collection.dart

@@ -184,6 +184,57 @@ class GeometryCollection<E extends Geometry> extends Geometry {
     );
   }
 
+  @override
+  GeometryCollection populated({
+    bool traverse = false,
+    bool onBounds = true,
+  }) {
+    if (onBounds) {
+      // populate geometries when traversing is asked
+      final coll = traverse && geometries.isNotEmpty
+          ? geometries
+              .map<E>(
+                (f) => f.populated(traverse: traverse, onBounds: onBounds) as E,
+              )
+              .toList(growable: false)
+          : geometries;
+
+      // create a new collection if geometries changed or bounds was unpopulated
+      if (coll != geometries || (bounds == null && coll.isNotEmpty)) {
+        return GeometryCollection<E>._(
+          coll,
+          coordType,
+          bounds: _buildBoundsFrom(coll, coordType),
+        );
+      }
+    }
+    return this;
+  }
+
+  @override
+  GeometryCollection unpopulated({
+    bool traverse = false,
+    bool onBounds = true,
+  }) {
+    if (onBounds) {
+      // unpopulate geometries when traversing is asked
+      final coll = traverse && geometries.isNotEmpty
+          ? geometries
+              .map<E>(
+                (f) =>
+                    f.unpopulated(traverse: traverse, onBounds: onBounds) as E,
+              )
+              .toList(growable: false)
+          : geometries;
+
+      // create a new collection if geometries changed or bounds was populated
+      if (coll != geometries || bounds != null) {
+        return GeometryCollection<E>._(coll, coordType);
+      }
+    }
+    return this;
+  }
+
   @override
   GeometryCollection<E> project(Projection projection) {
     final projected = _geometries

dart/geobase/lib/src/vector_data/model/geometry/linestring.dart

@@ -179,9 +179,9 @@ class LineString extends SimpleGeometry {
     if (recalculate || bounds == null) {
       // return a new linestring (chain kept intact) with populated bounds
       return LineString(
-        _chain,
+        chain,
         bounds: BoundsBuilder.calculateBounds(
-          array: _chain,
+          array: chain,
           type: coordType,
         ),
       );
@@ -191,6 +191,40 @@ class LineString extends SimpleGeometry {
     }
   }
 
+  @override
+  LineString populated({
+    bool traverse = false,
+    bool onBounds = true,
+  }) {
+    if (onBounds) {
+      // create a new geometry if bounds was unpopulated and geometry not empty
+      if (bounds == null && !isEmpty) {
+        return LineString(
+          chain,
+          bounds: BoundsBuilder.calculateBounds(
+            array: chain,
+            type: coordType,
+          ),
+        );
+      }
+    }
+    return this;
+  }
+
+  @override
+  LineString unpopulated({
+    bool traverse = false,
+    bool onBounds = true,
+  }) {
+    if (onBounds) {
+      // create a new geometry if bounds was populated
+      if (bounds != null) {
+        return LineString(chain);
+      }
+    }
+    return this;
+  }
+
   @override
   LineString project(Projection projection) {
     final projected = _chain.project(projection);

dart/geobase/lib/src/vector_data/model/geometry/multi_linestring.dart

@@ -205,9 +205,9 @@ class MultiLineString extends SimpleGeometry {
     if (recalculate || bounds == null) {
       // return a new MultiLineString (chains kept intact) with populated bounds
       return MultiLineString(
-        _lineStrings,
+        chains,
         bounds: BoundsBuilder.calculateBounds(
-          arrays: _lineStrings,
+          arrays: chains,
           type: coordType,
         ),
       );
@@ -217,6 +217,40 @@ class MultiLineString extends SimpleGeometry {
     }
   }
 
+  @override
+  MultiLineString populated({
+    bool traverse = false,
+    bool onBounds = true,
+  }) {
+    if (onBounds) {
+      // create a new geometry if bounds was unpopulated and geometry not empty
+      if (bounds == null && !isEmpty) {
+        return MultiLineString(
+          chains,
+          bounds: BoundsBuilder.calculateBounds(
+            arrays: chains,
+            type: coordType,
+          ),
+        );
+      }
+    }
+    return this;
+  }
+
+  @override
+  MultiLineString unpopulated({
+    bool traverse = false,
+    bool onBounds = true,
+  }) {
+    if (onBounds) {
+      // create a new geometry if bounds was populated
+      if (bounds != null) {
+        return MultiLineString(chains);
+      }
+    }
+    return this;
+  }
+
   @override
   MultiLineString project(Projection projection) {
     final projected = _lineStrings