bounding box support

[gpl/argeo-suite.git] / js / src / geo / OpenLayersMapPart.js

diff --git a/js/src/geo/OpenLayersMapPart.js b/js/src/geo/OpenLayersMapPart.js
index a75956680ee1e165ebf0151015d973725df8ef62..71b9a17b0574dd1539e1eb00c4cc5fa7823598c6 100644 (file)
--- a/js/src/geo/OpenLayersMapPart.js
+++ b/js/src/geo/OpenLayersMapPart.js
@@ -6,7 +6,7 @@ import Map from 'ol/Map.js';
 import View from 'ol/View.js';
 import OSM from 'ol/source/OSM.js';
 import TileLayer from 'ol/layer/Tile.js';
-import { fromLonLat, getPointResolution } from 'ol/proj.js';
+import { fromLonLat, getPointResolution, transformExtent } from 'ol/proj.js';
 import VectorSource from 'ol/source/Vector.js';
 import Feature from 'ol/Feature.js';
 import { Point } from 'ol/geom.js';
@@ -21,6 +21,8 @@ import * as SLDReader from '@nieuwlandgeo/sldreader';
 
 import MapPart from './MapPart.js';
 
+import { bbox } from 'ol/loadingstrategy';
+
 /** OpenLayers implementation of MapPart. */
 export default class OpenLayersMapPart extends MapPart {
        /** The OpenLayers Map. */
@@ -46,12 +48,14 @@ export default class OpenLayersMapPart extends MapPart {
                                //                                                                      transition: 0,
                                //                                                              }),
                        ],
-                       //                      view: new View({
-                       //                              center: [0, 0],
-                       //                              zoom: 2,
-                       //                      }),
+                       //                                              view: new View({
+                       //                                                      projection: 'EPSG:4326',
+                       //                                                      center: [0, 0],
+                       //                                                      zoom: 2,
+                       //                                              }),
                        target: this.getMapName(),
                });
+               //this.#map.getView().set('projection', 'EPSG:4326', true);
        }
 
        /* GEOGRAPHICAL METHODS */
@@ -282,4 +286,44 @@ export default class OpenLayersMapPart extends MapPart {
                });
                vectorLayer.setStyle(olStyleFunction);
        }
-}
\ No newline at end of file
+
+       //
+       // BBOX
+       //
+       applyBboxStrategy(layerName) {
+               const layer = this.getLayerByName(layerName);
+               const vectorSource = layer.getSource();
+               const baseUrl = vectorSource.getUrl();
+               if (typeof baseUrl === 'function')
+                       throw new Error('A strategy was already applied to layer ' + layerName);
+
+               const loadFunction = function(extent, resolution, projection, success, failure) {
+
+                       const proj = projection.getCode();
+                       var bbox = transformExtent(extent, proj, 'EPSG:4326');
+
+                       const url = baseUrl + '&' +
+                               'bbox=' + bbox.join(',') ;
+//                             'bbox=' + extent.join(',') + ',' + proj;
+                       const xhr = new XMLHttpRequest();
+                       xhr.open('GET', url);
+                       const onError = function() {
+                               vectorSource.removeLoadedExtent(extent);
+                               failure();
+                       }
+                       xhr.onerror = onError;
+                       xhr.onload = function() {
+                               if (xhr.status == 200) {
+                                       const features = vectorSource.getFormat().readFeatures(xhr.responseText);
+                                       vectorSource.addFeatures(features);
+                                       success(features);
+                               } else {
+                                       onError();
+                               }
+                       }
+                       xhr.send();
+               }
+
+               vectorSource.setLoader(loadFunction);
+       }
+}