Extract nodata values from metadata when possible

examples/cog-math-multisource.js

@@ -59,7 +59,7 @@ const map = new Map({
   ],
   view: new View({
     center: [1900000, 6100000],
-    zoom: 15,
+    zoom: 13,
     minZoom: 10,
   }),
 });

examples/cog-math.js

@@ -80,13 +80,11 @@ const map = new Map({
           {
             // visible red, band 1 in the style expression above
             url: 'https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/2020/S2A_36QWD_20200701_0_L2A/B04.tif',
-            nodata: 0,
             max: 10000,
           },
           {
             // near infrared, band 2 in the style expression above
             url: 'https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/2020/S2A_36QWD_20200701_0_L2A/B08.tif',
-            nodata: 0,
             max: 10000,
           },
         ],

examples/cog.html

@@ -4,8 +4,7 @@ title: Cloud Optimized GeoTIFF (COG)
 shortdesc: Rendering a COG as a tiled layer.
 docs: >
   Tiled data from a Cloud Optimized GeoTIFF (COG) can be rendered as a layer.  In this
-  example, a single 3-band GeoTIFF is used to render RGB data.  The `nodata` property is
-  used to avoid rendering pixels where all three bands are 0.
+  example, a single 3-band GeoTIFF is used to render RGB data.
 tags: "cog"
 ---
 <div id="map" class="map"></div>

examples/cog.js

@@ -26,7 +26,6 @@ const map = new Map({
         sources: [
           {
             url: 'https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/2020/S2A_36QWD_20200701_0_L2A/TCI.tif',
-            nodata: 0,
           },
         ],
       }),