Add displayPreview and displayOverview options #651

Author: m-mohr

config.js

@@ -29,6 +29,8 @@ module.exports = {
     apiCatalogPriority: null,
     useTileLayerAsFallback: false,
     displayGeoTiffByDefault: false,
+    displayPreview: true,
+    displayOverview: true,
     buildTileUrlTemplate: null,
     getMapSourceOptions: null,
     stacProxyUrl: null,

config.schema.json

@@ -82,6 +82,16 @@
         "boolean"
       ]
     },
+    "displayPreview": {
+      "type": [
+        "boolean"
+      ]
+    },
+    "displayOverview": {
+      "type": [
+        "boolean"
+      ]
+    },
     "buildTileUrlTemplate": {
       "type": [
         "null"

docs/options.md

@@ -365,10 +365,23 @@ To clarify the behavior, please have a look at the following table:
 | true  | null     | client-side | none        |
 | false | null     | none        | none        |
 
+### displayPreview
+
+If set to `true` (default), displays preview images that a browser can display (e.g. PNG, JPEG) on the map as default visualization, i.e. from assets with any of the roles `thumbnail`, `overview`, or a link with relation type `preview`.
+The previews are often not covering the full extents and as such may be placed incorrectly on the map.
+
+If both `displayPreview` and `displayOverview` (see below) are enabled, STAC Browser prefers the overviews (COGs) over the previews (PNG, JPEG, ...).
+
+### displayOverview
+
+If set to `true` (default), allows to display COGs and, if `displayGeoTiffByDefault` is enabled, GeoTiffs on the map as default visualization, usually from an asset with role `overview` or `visual`.
+
 ### displayGeoTiffByDefault
 
 If set to `true`, the map also shows non-cloud-optimized GeoTiff files by default. Otherwise (`false`, default), it only shows COGs and you can only enforce showing GeoTiffs to be loaded with the "Show on map" button but they are never loaded automatically.
-Loading non-cloud-optimized GeoTiffs only works reliably for smaller files (< 1MB). It may also work for larger files, but it depends a lot on the underlying client hardware and software.
+Loading non-cloud-optimized GeoTiffs only works reliably for smaller files (< 1MB) with a certain structure. It may also work for larger files, but it depends a lot on the underlying client hardware and software.
+
+Related OpenLayers issue: [openlayers#16961](https://github.com/openlayers/openlayers/issues/16961)
 
 ### crs
 

src/components/Map.vue

@@ -138,7 +138,6 @@ export default {
         children: this.items,
         assets: this.assets || null,
         displayWebMapLink: true,
-        displayPreview: !this.items,
         disableMigration: true,
       });
       this.stacLayer = new StacLayer(options);

src/components/maps/MapMixin.js

@@ -22,11 +22,13 @@ register(proj4); // required to support source reprojection
 
 export default {
   computed: {
-    ...mapState(['buildTileUrlTemplate', 'crossOriginMedia', 'displayGeoTiffByDefault', 'getMapSourceOptions', 'useTileLayerAsFallback']),
+    ...mapState(['buildTileUrlTemplate', 'crossOriginMedia', 'displayGeoTiffByDefault', 'displayPreview', 'displayOverview', 'getMapSourceOptions', 'useTileLayerAsFallback']),
     stacLayerOptions() {
       return {
         buildTileUrlTemplate: this.buildTileUrlTemplate,
         crossOriginMedia: this.crossOriginMedia,
+        displayPreview: this.displayPreview,
+        displayOverview: this.displayOverview,
         displayGeoTiffByDefault: this.displayGeoTiffByDefault,
         useTileLayerAsFallback: this.useTileLayerAsFallback,
         getSourceOptions: this.getMapSourceOptions,