feat: Add geometry-type property

placemark · Oct 28, 2022 · 59df17e · 59df17e
1 parent 4a5b220
commit 59df17e
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Showing 3 changed files with 116 additions and 9 deletions.
diff --git a/lib/__snapshots__/index.test.ts.snap b/lib/__snapshots__/index.test.ts.snap
@@ -12797,6 +12797,7 @@ Object {
         "type": "Polygon",
       },
       "properties": Object {
+        "@geometry-type": "groundoverlay",
         "description": "Overlay shows Mount Etna erupting 
           on July 13th, 2001.",
         "icon": "https://developers.google.com/kml/documentation/images/etna.jpg",
@@ -12813,7 +12814,45 @@ exports[`toGeoJSON ground_overlay.kml 2`] = `
 Object {
   "children": Array [
     Object {
-      "children": Array [],
+      "children": Array [
+        Object {
+          "geometry": Object {
+            "coordinates": Array [
+              Array [
+                Array [
+                  14.60128369746704,
+                  37.46543388598137,
+                ],
+                Array [
+                  14.60128369746704,
+                  37.91904192681665,
+                ],
+                Array [
+                  15.35832653742206,
+                  37.91904192681665,
+                ],
+                Array [
+                  14.60128369746704,
+                  37.91904192681665,
+                ],
+                Array [
+                  14.60128369746704,
+                  37.46543388598137,
+                ],
+              ],
+            ],
+            "type": "Polygon",
+          },
+          "properties": Object {
+            "@geometry-type": "groundoverlay",
+            "description": "Overlay shows Mount Etna erupting 
+          on July 13th, 2001.",
+            "icon": "https://developers.google.com/kml/documentation/images/etna.jpg",
+            "name": "Large-scale overlay on terrain",
+          },
+          "type": "Feature",
+        },
+      ],
       "meta": Object {
         "description": "Examples of ground overlays",
         "name": "Ground Overlays",
@@ -12857,6 +12896,7 @@ Object {
         "type": "Polygon",
       },
       "properties": Object {
+        "@geometry-type": "groundoverlay",
         "icon": "http://developers.google.com/kml/documentation/images/rectangle.gif",
         "name": "gx:LatLonQuad Example",
       },
@@ -12869,7 +12909,43 @@ Object {
 
 exports[`toGeoJSON ground_overlay_quad.kml 2`] = `
 Object {
-  "children": Array [],
+  "children": Array [
+    Object {
+      "geometry": Object {
+        "coordinates": Array [
+          Array [
+            Array [
+              81.601884,
+              44.160723,
+            ],
+            Array [
+              83.529902,
+              43.665148,
+            ],
+            Array [
+              82.947737,
+              44.248831,
+            ],
+            Array [
+              81.509322,
+              44.321015,
+            ],
+            Array [
+              81.601884,
+              44.160723,
+            ],
+          ],
+        ],
+        "type": "Polygon",
+      },
+      "properties": Object {
+        "@geometry-type": "groundoverlay",
+        "icon": "http://developers.google.com/kml/documentation/images/rectangle.gif",
+        "name": "gx:LatLonQuad Example",
+      },
+      "type": "Feature",
+    },
+  ],
   "type": "root",
 }
 `;

diff --git a/lib/kml.ts b/lib/kml.ts
@@ -126,6 +126,23 @@ function getFolder(node: Element): Folder {
  *   ]
  * }
  * ```
+ *
+ * ### GroundOverlay
+ *
+ * GroundOverlay elements are converted into
+ * `Feature` objects with `Polygon` geometries,
+ * a property like:
+ *
+ * ```json
+ * {
+ *   "@geometry-type": "groundoverlay"
+ * }
+ * ```
+ *
+ * And the ground overlay's image URL in the `href`
+ * property. Ground overlays will need to be displayed
+ * with a separate method to other features, depending
+ * on which map framework you're using.
  */
 export function kmlWithFolders(node: Document): Root {
   const styleMap = buildStyleMap(node);
@@ -142,6 +159,14 @@ export function kmlWithFolders(node: Document): Root {
   ) {
     if (isElement(node)) {
       switch (node.tagName) {
+        case "GroundOverlay": {
+          placemarks.push(node);
+          const placemark = getGroundOverlay(node, styleMap);
+          if (placemark) {
+            pointer.children.push(placemark);
+          }
+          break;
+        }
         case "Placemark": {
           placemarks.push(node);
           const placemark = getPlacemark(node, styleMap);

diff --git a/lib/kml/ground_overlay.ts b/lib/kml/ground_overlay.ts
@@ -1,4 +1,4 @@
-import { Feature, Geometry } from "geojson";
+import { Feature, Polygon } from "geojson";
 import { StyleMap, get1, num1, getMulti } from "../shared";
 import {
   extractCascadedStyle,
@@ -10,7 +10,7 @@ import {
 import { extractIconHref, extractStyle } from "./extractStyle";
 import { coord, fixRing, getCoordinates } from "./geometry";
 
-function getGroundOverlayBox(node: Element): Geometry | null {
+function getGroundOverlayBox(node: Element): Polygon | null {
   const latLonQuad = get1(node, "gx:LatLonQuad");
 
   if (latLonQuad) {
@@ -21,6 +21,10 @@ function getGroundOverlayBox(node: Element): Geometry | null {
     };
   }
 
+  return getLatLonBox(node);
+}
+
+function getLatLonBox(node: Element): Polygon | null {
   const latLonBox = get1(node, "LatLonBox");
 
   if (latLonBox) {
@@ -29,9 +33,6 @@ function getGroundOverlayBox(node: Element): Geometry | null {
     const east = num1(latLonBox, "east");
     const south = num1(latLonBox, "south");
 
-    // FIXME: rotation support
-    // const rotation = num1(latLonBox, "rotation");
-
     if (
       typeof north === "number" &&
       typeof south === "number" &&
@@ -59,13 +60,18 @@ function getGroundOverlayBox(node: Element): Geometry | null {
 export function getGroundOverlay(
   node: Element,
   styleMap: StyleMap
-): Feature<Geometry | null> {
+): Feature<Polygon | null> {
   const geometry = getGroundOverlayBox(node);
 
-  const feature: Feature<Geometry | null> = {
+  const feature: Feature<Polygon | null> = {
     type: "Feature",
     geometry,
     properties: Object.assign(
+      /**
+       * Related to
+       * https://gist.github.com/tmcw/037a1cb6660d74a392e9da7446540f46
+       */
+      { "@geometry-type": "groundoverlay" },
       getMulti(node, [
         "name",
         "address",