[OpenLayers-Users] COG and basemap

[Marc Jansen]

Hi Jakob,

nice that you have it working now. WRT the reprojection, yes, that is
not possible right now, but:
https://github.com/openlayers/openlayers/pull/13654

Best

Marc


Am 27.05.22 um 12:32 schrieb Jakob Miksch:
> Hi Marc,
>
> If I leave out extent, the COG is displayed on a wrong place. (Should
> be Buonos Aires, but is placed in France).
> Increasing the extent shows an visual effect, but still causes the OSM
> map to be placed on the wrong place.
>
> Meanwhile, I made it work inspired by
> https://stackoverflow.com/a/70116989 and
> https://codesandbox.io/s/cog-forked-tmswq?file=/main.js
>
> It seems I needed to define the projection using Proj4js and not with
> OL directly.
>
> One learning is that apparently COGs cannot be reprojected by OL.
> (Please correct me if I am wrong)
> Initially I tried to create something similar as here:
> https://cholmes.github.io/cog-map/
> This app displays COGs in any CRS on WebMercator, BUT it actually uses
> the backend service https://tiles.rdnt.io/ for proxying and reprojection.
>
> Best,
> Jakob
>
> importGeoTIFFfrom'ol/source/GeoTIFF.js';
> importMapfrom'ol/Map.js';
> importWebGLTileLayerfrom'ol/layer/WebGLTile.js';
> importViewfrom'ol/View.js';
> importTileLayerfrom'ol/layer/Tile';
> importOSMfrom'ol/source/OSM';
> importproj4from"proj4";
> import{ register} from"ol/proj/proj4";
> import{ fromLonLat} from"ol/proj";
> constepsgCode= "EPSG:32721";
> proj4.defs(epsgCode,"+proj=utm +zone=21 +south +datum=WGS84 +units=m
> +no_defs");
> register(proj4);
> constcogSource= newGeoTIFF({
> sources:[
> {
> url:'https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/21/H/UB/2021/9/S2B_21HUB_20210915_0_L2A/TCI.tif',
> },
> ],
> });
> constcogLayer= newWebGLTileLayer({
> source:cogSource,
> });
> newMap({
> target:'map',
> layers:[
> newTileLayer({
> source:newOSM()
> }),
> cogLayer
> ],
> view:newView({
> projection:epsgCode,
> center:fromLonLat([-58.205,-34.833], epsgCode),
> zoom:10,
> }),
> });
>
>
> Am 27.05.22 um 10:35 schrieb Marc Jansen:
>>
>> Hi Jakob,
>>
>> what happens if you change the extent of the view (leave it out,
>> configure it to sth. bigger that the extent of the source)?
>>
>> Just a wild guess.
>>
>> Best
>>
>> Marc
>>
>>
>> Am 27.05.22 um 10:18 schrieb Jakob Miksch:
>>> Dear list,
>>>
>>> I am trying to display COGs in OpenLayers. This works well for
>>> single images. However, I would like to add more more layers like a
>>> basemap. But then the view is blocked to the extent of the COG. See
>>> my example below.
>>>
>>> Is there a way to overlay a COG on a basemap and still be able to
>>> zoom and pan wherever I want and not being restricted by the extent
>>> of the COG?
>>>
>>> best regards,
>>> Jakob
>>>
>>> importGeoTIFFfrom'ol/source/GeoTIFF.js';
>>> importMapfrom'ol/Map.js';
>>> importProjectionfrom'ol/proj/Projection.js';
>>> importWebGLTileLayerfrom'ol/layer/WebGLTile.js';
>>> importViewfrom'ol/View.js';
>>> import{getCenter} from'ol/extent.js';
>>> importTileLayerfrom'ol/layer/Tile';
>>> importOSMfrom'ol/source/OSM';
>>> constprojection= newProjection({
>>> code:'EPSG:32721',
>>> units:'m',
>>> });
>>> // metadata from
>>> https://s3.us-west-2.amazonaws.com/sentinel-cogs/sentinel-s2-l2a-cogs/21/H/UB/2021/9/S2B_21HUB_20210915_0_L2A/S2B_21HUB_20210915_0_L2A.json
>>> constsourceExtent= [300000, 6090260, 409760, 6200020];
>>> constcogSource= newGeoTIFF({
>>> sources:[
>>> {
>>> url:'https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/21/H/UB/2021/9/S2B_21HUB_20210915_0_L2A/TCI.tif',
>>> },
>>> ],
>>> });
>>> constcogLayer= newWebGLTileLayer({
>>> source:cogSource,
>>> });
>>> newMap({
>>> target:'map',
>>> layers:[
>>> newTileLayer({
>>> source:newOSM()
>>> }),
>>> cogLayer
>>> ],
>>> view:newView({
>>> projection:projection,
>>> center:getCenter(sourceExtent),
>>> extent:sourceExtent,
>>> zoom:1,
>>> }),
>>> });
>>> -- 
>>> Jakob Miksch
>>> Geoinformatiker
>>>
>>> meggsimum - Büro für Geoinformatik
>>> Christian Mayer
>>> Schillerstr. 2a    | 67112 Mutterstadt
>>> info at meggsimum.de | www.meggsimum.de
>>> T 06231 - 6298988  |
>>>
>>> _______________________________________________
>>> Users mailing list
>>> Users at lists.osgeo.org
>>> https://lists.osgeo.org/mailman/listinfo/openlayers-users
>> -- 
>> Marc Jansen
>> — Geschäftsführer —
>>
>> terrestris GmbH & Co. KG
>> Kölnstraße 99
>> 53111 Bonn
>>
>> Tel:   +49 (0)228 / 96 28 99 -53
>> Fax:   +49 (0)228 / 96 28 99 -57
>>
>> Email: jansen at terrestris.de
>> Web:   https://www.terrestris.de
>>
>> Amtsgericht Bonn, HRA 6835
>> Komplementärin: terrestris Verwaltungsgesellschaft mbH
>> vertreten durch: Torsten Brassat, Marc Jansen
>>   
>> Informationen über Ihre gespeicherten Daten finden Sie auf unserer Homepage unter folgendem Link: https://www.terrestris.de/datenschutzerklaerung/
>>
>> _______________________________________________
>> Users mailing list
>> Users at lists.osgeo.org
>> https://lists.osgeo.org/mailman/listinfo/openlayers-users
>
> -- 
> Jakob Miksch
> Geoinformatiker
>
> meggsimum - Büro für Geoinformatik
> Christian Mayer
> Schillerstr. 2a    | 67112 Mutterstadt
> info at meggsimum.de | www.meggsimum.de
> T 06231 - 6298988  |
>
> _______________________________________________
> Users mailing list
> Users at lists.osgeo.org
> https://lists.osgeo.org/mailman/listinfo/openlayers-users

-- 
Marc Jansen
— Geschäftsführer —

terrestris GmbH & Co. KG
Kölnstraße 99
53111 Bonn

Tel:   +49 (0)228 / 96 28 99 -53
Fax:   +49 (0)228 / 96 28 99 -57

Email: jansen at terrestris.de
Web:   https://www.terrestris.de

Amtsgericht Bonn, HRA 6835
Komplementärin: terrestris Verwaltungsgesellschaft mbH
vertreten durch: Torsten Brassat, Marc Jansen
  
Informationen über Ihre gespeicherten Daten finden Sie auf unserer Homepage unter folgendem Link: https://www.terrestris.de/datenschutzerklaerung/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/openlayers-users/attachments/20220527/165416f9/attachment-0001.htm>