Feature/add lerc decoder

[grallewellyn]

NOTE THAT THIS IS STILL A WIP: Megan needs to add VIIRS and OMI lerc layers to worldview endpoints so I can remove some of this ugly hardcoding stuff
Right now, I am accessing the lerc layers by running Joe's ec2 instance and using localhost, so we need to publish the lerc layers
Once the LERC layer is added to the official endpoints, we can get the snapshot that matches the rest of the snapshots by running npm run build which gets the snapshot with a request to https://wvs.earthdata.nasa.gov/api/v1/snapshot
I am keeping the incorrect web/images/layers/previews/geographic/VIIRS_VNP46A1_LERC_v1.jpg in this PR as a reminder for now

We also need to update the legend images for both layers

I also still need to create tests that the LERC layers are showing up properly

I added OMI data as OMI_Total_NO2_LRC_v1 in measurements/Nitrogen Dioxide/Aura/OMI. If this is not a good placement for the layer, I also found measurements/aerosol_index /aura/OMI and measurements/ozone/aura/OMI

Description

Adds the LERC decoder to worldview so that LERC layers are now supported. Some other notes:

• I removed the original difference/ average code for the LERC color decoder because it did not appear to be a feature in worldview. This part of drawTile was for comparing the average/ difference between 2 layers. The closest feature in worldview was comparison mode which is just displaying 2 layers normally but side by side
• Using default gray scalar function for original coloring

export function getGreyScalar(val, min, max) {
  const colors = [];
  colors[0] = 255 * ((val - min) / (max - min));
  [colors[1], colors[2]] = [colors[0], colors[0]];
  return colors;
}

We agreed this was okay in a meeting 2/4/2025

• When the filter is on for drawTile (which is the case if the user altered the layer thresholds), then don’t show values above or below the current threshold
• For setting the no data value, I didn’t want to alter the disabled key in the palette object because that would affect other layers, so I added a new tag- noDataValue. I did not see anything for schema for the palette, so it seems okay to add a new key to palette objects. Also, worldview during the build stage breaks the colormaps up if there is a transparent/ noDataValue, so I took this into account
• I could have extracted out setting the lerc tileLoadFunction, but I think keeping it in createLayerWMTS is best for right now because we only support LERC with WMTS at the moment
• I know the 2 if statements checking if the layer is a lerc layer and then doing a different action (not setting the tileClass and setting the tileLoadFunction) are not the prettiest, but I spent quite a bit of time trying to get around them and could not figure it out. Maybe another worldview developer could give suggestions or we can create a new ticket for it. I think there should be a better way to set a custom tileLoadFunction for other use cases and this would entail having this custom tile load function properly called when the palette changes (the reason I can’t set the tileClass for LERC layers is because the LERC til loader is not called when the palette is changed so the LERC layer will not display properly)
• I know passing the state object to tileLoader isn’t ideal, but we need to be able to get the resolution, palette, and legend from the state in the LERC tileloader

Things discussed but were resolved:

• using more than 256 colors (we are using 24 bit color depth already)
• we don't want to increase the max for VIIRS to be more than 382 because most values are within that range and increasing it higher makes it harder to see the lower values

We should add this documentation somewhere too:

Steps to add a layer worldview

1. Add your layername to config/default/common/config/wv.json/layerOrder.json
2. Add a json file with details about your layer to config/default/common/config/wv.json/layers/... (i.e. config/default/common/config/wv.json/layers/viirs/snpp/VIIRS_VNP46A1_LERC_v1.json)
3. Add to a category that fits your layer at config/default/common/config/wv.json/... (i.e.
   config/default/common/config/wv.json/measurements/Earth at Night.json)
4. Add the layer to the GetCapabilities, the best way I have found to do this for testing is edit the xml string in the file tasks/build-options/extractConfigFromWMTS.js in the processEntry function and also edit the xml string in the file tasks/build-options/getCapabilities.js in the processGetCapabilities function. You should edit the xml string to add the details of your layer in XML format like I do here:

   worldview/tasks/build-options/extractConfigFromWMTS.js

   Lines 121 to 123 in b983eb3

   	const endFirstLayer = xml.indexOf('</Layer>') + 8
   	const lercStr = '<Layer><ows:Title xml:lang=\'en\'>VIIRS Lerc layer for testing</ows:Title><ows:WGS84BoundingBox crs=\'urn:ogc:def:crs:OGC:2:84\'><ows:LowerCorner>-180 -90</ows:LowerCorner><ows:UpperCorner>180 90</ows:UpperCorner></ows:WGS84BoundingBox><ows:Identifier>VIIRS_SNPP_DayNightBand_At_Sensor_Radiance_LERC</ows:Identifier><ows:Metadata xlink:role=\'http://earthdata.nasa.gov/gibs/metadata-type/colormap/1.0\' xlink:type=\'simple\' xlink:title=\'GIBS Color Map: Data - RGB Mapping\' xlink:href=\'https://gitc.earthdata.nasa.gov/colormaps/v1.0/VIIRS_DayNightBand_At_Sensor_Radiance.xml\'/><ows:Metadata xlink:role=\'http://earthdata.nasa.gov/gibs/metadata-type/colormap/1.3\' xlink:type=\'simple\' xlink:title=\'GIBS Color Map: Data - RGB Mapping\' xlink:href=\'https://gitc.earthdata.nasa.gov/colormaps/v1.3/VIIRS_DayNightBand_At_Sensor_Radiance.xml\'/><ows:Metadata xlink:role=\'http://earthdata.nasa.gov/gibs/metadata-type/colormap/\' xlink:type=\'simple\' xlink:title=\'GIBS Color Map: Data - RGB Mapping\' xlink:href=\'https://gitc.earthdata.nasa.gov/colormaps/v1.3/VIIRS_DayNightBand_At_Sensor_Radiance.xml\'/><Style isDefault=\'true\'><ows:Title xml:lang=\'en\'>default</ows:Title><ows:Identifier>default</ows:Identifier><LegendURL height=\'85.5\' xlink:type=\'simple\' xlink:role=\'http://earthdata.nasa.gov/gibs/legend-type/horizontal\' width=\'378.0\' xlink:title=\'GIBS Color Map Legend: Horizontal\' xlink:href=\'https://gitc.earthdata.nasa.gov/legends/VIIRS_DayNightBand_At_Sensor_Radiance_H.svg\' format=\'image/svg+xml\'/><LegendURL height=\'288.0\' xlink:type=\'simple\' xlink:role=\'http://earthdata.nasa.gov/gibs/legend-type/vertical\' width=\'135.0\' xlink:title=\'GIBS Color Map Legend: Vertical\' xlink:href=\'https://gitc.earthdata.nasa.gov/legends/VIIRS_DayNightBand_At_Sensor_Radiance_V.svg\' format=\'image/svg+xml\'/></Style><Dimension><ows:Identifier>Time</ows:Identifier><ows:UOM>ISO8601</ows:UOM><Default>2022-07-31</Default><Current>false</Current><Value>2013-07-31/2022-07-01/P1D</Value></Dimension><TileMatrixSetLink><TileMatrixSet>500m</TileMatrixSet></TileMatrixSetLink><Format>image/lerc</Format><ResourceURL template=\'https://localhost:8080/wmts/epsg4326/best/wmts.cgi?Time={Time}&amp;layer=VIIRS_SNPP_DayNightBand_At_Sensor_Radiance_LERC&amp;style=default&amp;tilematrixset={TileMatrixSet}&amp;Service=WMTS&amp;Request=GetTile&amp;Version=1.0.0&amp;Format=image%2Flerc&amp;TileMatrix={TileMatrix}&amp;TileCol={TileCol}&amp;TileRow={TileRow}\''
   	const lercStr2 = 'format=\'image/lerc\' resourceType=\'tile\'/></Layer>'

5. Add metadata in the file tasks/build-options/getVisMetadata.js in the function getMetadata. The layerId will come in the same as what you put above but with no data, so you have to catch when layerId === then input the metadata like I did here:

   worldview/tasks/build-options/getVisMetadata.js

   Lines 163 to 186 in b983eb3

   	if (layerId === 'VIIRS_SNPP_DayNightBand_At_Sensor_Radiance_LERC') {
   	const metadata = {
   	title: 'VIIRS Lerc layer for testing',
   	subtitle: 'Suomi NPP / VIIRS',
   	ongoing: true,
   	measurement: 'Earth at Night',
   	retentionPeriod: -1,
   	daynight: [
   	'night'
   	],
   	conceptIds: [],
   	orbitDirection: [
   	'descending'
   	],
   	layerPeriod: 'Daily'
   	}
   	layerMetadata[layerId] = await getDAAC(metadata)
   	let metadataKeys = Object.keys(layerMetadata[layerId])
   	metadataKeys = metadataKeys.filter(x => !useKeys.includes(x))
   	for (const key of metadataKeys) {
   	delete layerMetadata[layerId][key]
   	}
   	return
   	}

[Description of the bug or feature]

• Adding LERC layers to worldview

[If this is a relatively large or complex change, start a discussion by explaining why you chose the solution you did and what alternatives you considered, etc...]
Potential discussion topics in bullets above

How To Test

[Provide whatever information a reviewer might need to know in order to verify that the changes made in this PR are working as expected. If there are special build steps that need to be taken in order to get these changes to run (building while on a separate branch, running npm ci, etc) include them here.]

• For bugfixes: What steps need to be taken in the UI to verify the bug is fixed?
• For enhancements and features: What is the expected functionality being added/modified? How can a reviewer verify this?

Can now open VIIRS Nighttime Imagery LERC layer to the map and view it. This LERC layer should have all functionality like changing the palette, min/max values, and opacity. All other layers and behavior should function the same

1. Open with these URL parameters: http://localhost:3000/?lg=true&t=2022-07-01-T18%3A36%3A48Z
2. Add layers
3. Add the VIIRS lerc layer by searching it
4. Verify expected result

I verified that I could delete my local copy of worldview and rebuild/ run

PR Submission Checklist

This is simply a reminder of what we are going to look for before merging your code.

• I have read the CONTRIBUTING doc
• I have added necessary documentation (if applicable)
• I have added tests that prove my fix is effective or that my feature works (if applicable)
• Any dependent changes have been merged and published in downstream modules (if applicable)

Merging

Please use the squash and merge commit method unless each commit in your branch is vital to the commit history of main.

@nasa-gibs/worldview

[jtroberts]

We should rename this layer to maybe VIIRS_SNPP_DayNightBand_LERC.

[grallewellyn]

I agree and I will change once we ingest more data under that ID since the ID here is used for the imagery requests
I updated the add more imagery ticket to include this new ID