Epic Tracker ToDos - Terrain-Viewer

[jo-chemla]

Quick Fixes

• Phasing-out/Sunsetting original Iconem/historical-satellite see UI redesign v2 mockup : SidePanel for Layers and BottomPanel for Timeline historical-satellite#30 and Epic tracker historical-satellite#58
• When using url-param terrainSrc1=terrainId, is it added from sample to BYOD? can one prepopulate with a election like ign-dsm and ign-dtm?
• in compare and blend, capture date should default to source + date rather than off.
• bug in beta.historical, when no latlon zoom pitch etc present in url, it's not using the default low-zoom whole earth defaults;
• in historical imagery timeline, the labels below the timeline should only appear if there are just 2x1 mode, only show for A if A is historical and on B if B is historical.
• match-colors do some sort of caching so we can easily toggle on/off the CSS filter toggle, probably cache just the transform so it gets reapplied instant
• Re-parse and read all docs, evaluate what's missing. Could eg add sections on:
  • Export DSM/Contours/Historical/Share to socials.
  • Project Import/Export and local storage persistence for draws, sources, local COG, and settings section for this showing usage and free-up. local COG is probably mentioned in BYOD, not sure how detailed
  • Add a River-REM docs, eventually from a markdown mdx on the river-rem repo itself which would be source of truth, imported here from its github link?
  • tour kbd shortcuts link to the docs for up-to-date, description, so it appears at least in the docs walkthrough screenshot.
  • Add mention about feature iterator in drawings tools docs page
  • Add a note re streaming via maplibre geomatico vs titiler if it's not already present in the docs, as well as high precision quantization
  • in docs changelog page, add a note that it is also present in a settings dedicated panel
• matcap has a weird fade-in on the center of the screen, is it connected to the ray divergence from optical axis? Looks wrong
• We might want to rework phong at some point for sharpness, add some notes in your emory regarding your paragraph informative:
  Phong detail — it's not the lighting equation. I checked the ray/divergence hypothesis: the live phong uses a constant view vector for specular, which affects where highlights sit, not sharpness — a constant term can't blur anything spatially. The remaining softness vs native hillshade comes from the architecture: (1) native hillshade computes derivatives per device pixel in the fragment shader straight from the DEM texture, while our layer bakes normals into a fixed texel grid per tile — Nyquist-limited at that grid; (2) those normals are quantized to 8 bits per component (steps of ~1/127), which flattens subtle low-slope detail; (3) the normal texture is LINEAR-filtered, adding its own smoothing. If you want to chase native parity, the real fix is sampling the DEM texture and deriving normals per fragment in the live shader (a bigger job, but it would eliminate all three); cheaper options are a higher-precision normal encoding or simply re-adding a sharpness zoom level as an opt-in. Say the word on which, if any.
• Add meta-app-micro-frontends postMessage to forward url nuqs state from embedded iframe to meta wrapper
• Fix mobile timeline panel
• hard to use double pill slider on mobile for lin max bounds
• add mapbox and maptiler satellite from provided api keys
• integrate osm-editor-kit/maplibre-editor-layer-index osmlab/editor-layer-index osm editor layer index and editor kit see offerings in placemark integrating maplibre Move to MapLibre and provider-neutral routing placemark/placemark#269
• Mapterhorn Imagery Mapterhorn Imagery - Initial Ideas & Sources mapterhorn/mapterhorn#139 and
• placemark maplibre pr talk about Nextgis QMS and Mapterhorn imagery issue/pr
• showcased on awesome-maplibre, feature, river threads on socials etc, river-rem, historical, add to bellingcat-toolkit (repo) see thread Tool suggestion: Historical-Satellite and Terrain-Viewer from Iconem bellingcat/toolkit#892
• In terrain mode, we might want to let the user have the choice for viz-modes other than basemap to apply to all map views (sync viz modes across views) or to only a selection, via the button groups shaped like the view grid for every viz mode, rather than checkbox. It could also be useful in that case to port not only 2x1 side, but also N-grid up to 4x2 by porting from historical appMode.
• Eventually port the client-side iconem/River-REM in its own Tools panel or rather a complete appMode in itself (rather than tool actionable via toggle). the fetch rivers, build and compute detrended DSM minus Water Surface Level and applying colorramp, with slider/colorramp bounds, plus the button group switch between pure DSM vs RiverREM (each with its own slider and colorramp bounds).
• search-eo/historical-imagery availability data freshness over an AOIs list/samples,eg unesco sites last year Imagery availability and freshness over AOIs samples/list via search-eo / historical satellite #18
• Maxar API for Basemaps, Seamlines, STAC search: Integrate Maxar API for Basemaps, Seamlines, STAC search historical-satellite#37
• Smart hierarchical DSM/DTM source? Like a live-mapterhorn equivalent? like a STAC or 3D-tiles / 2D-tiles equivalent, parent groups hierarchy or resolution going always finer further down the tree hierarchy, to composite multiple sources and fetch the highest resolution available given a viewport (or matching viewport resolution), which would choose between IGN french, spain, mexico etc from samples? Also look at PDAL tindex geopackage export PR here tindex create: add support for writing STAC Geoparquet PDAL/PDAL#5007
• TBD integrate geojson editor like placemark.io repo or mapbox geojson.io (repo), for viewing feature properties, editing them, drawing etc
• Finish beta.historical replacement of legacy historical, pashing out (that could still be served by legacy.historical-satellite.iconem.com). make sure pure historical-satellite redirects to the new terrain-viewer
• upgrade to maplibre-gl-js v6. Also, potentially useful terrain bugfixes upstream on maplibre-gl-js/pulls that landed at v5 and v6: 7812 7813 7814 7284 7288 7549 7863
• Other layer types like COPC, 3Dtiles, see options:
  • 3DTilesRendererJS version following TerrainRGB Terrarium TMS integration, globe controls, soon hillshade, postprocessing etc see TerrainRGB, Terrarium Plugins: Further Improvements NASA-AMMOS/3DTilesRendererJS#1691: port a version of the app/renderer from maplibre to pure threejs with 3DTilesRendererJS, probably via r3f, Globe, threejs lighting effects, overlays, react-postprocessing etc. No COG yet for basemaps/terrain
  • native maplibre plugins, vanilla js, from opengeos/maplibre-gl-lidar, or Kanahiro/maplibre-copc-layer and 3Dtiles: Experiment 3Dtiles via official-example based on 3DTilesRendererJS/threejs layer sync or dvt3d/maplibre-three-plugin. These would be considered as completely different 3D sources, in their own xyz-sources panel, with also symbology managed completely differently.
  • deckgl-raster for basemaps/terrain, and eventually loaders.gl from visgl for formats like copc reed-soul/wasm-spatial-core/.../copc-loader, already supports 3dtiles, cog etc
  • others like RodrigoHamuy/react-three-map based on react-map-gl? Maybe simpler dvt3d/maplibre-three-plugin?
• Eventually Add support for quantized-mesh like Moon, Mars Cesium datasets and projects, or Plugins: Add support for other tiled formats NASA-AMMOS/3DTilesRendererJS#943 also see clement-igonet/maplibre-gl-3dtiles-terrain for a start probably
• ---
• Look at awesome-maplibre whether anything interesting is visible
• Do a shadscan, fix ux recommendations for accessibility etc, see scan prev. headless-shadcn. Some recommendations
  • apart from a11y
  • using toasts for all notifications (and there are various, during export, success, warnings or info message scattered across components),
  • eventually command bar Ctrl+K, start typing hillshade and it would return the hillshade checkbox or slider to be controlled via other keyboard like space + arrow keys (eventually focus to this control in sidebar, and give hint that user can use space and arrows to control opacity, or down to select other option like hillshade type, light direction (arrow keys again). Probably mostly up/down keys for selecting type, left/right for the slider values input.
• renovate bot to update package deps, also explore bundle size and tree shakeable.
• See inspiration combining DSM, DTM, slope faultines etc from IGN itself or jgaffuri/CartoHD and demo
• Test with more frescoes:
  • Cambodia frescoes (kutsheka battle, barratage mer de lait),
  • Jam unroll,
  • Biot,
  • vatican missing tiles, etc.
• ---
• Add strava see below source in details, requires cors proxy https://heatmap-external-b.strava.com/tiles/all/blue/{z}/{x}/{y}.png
• BYOD STAC sources to assemble multiple COGs or search collection
• STAC federated collection discovery 2026-07-30-stac-discovery blog post, live prod maap version and developmentseed/stac-collection-discovery frontend repo and backend stac-fastapi-collection-discovery. Also atlas stac-index and repo and stac-index
• Feature parity matrix: contours, export capability to WMS, Tilejson etc Feature matrix: Elevation source types vs Features + TiTiler case #16
• Attempt importing samples for DTMs (from DSMs + AI) of openlandmap/GEDTM30 global (paper, zenodo dataset) and south-america ANADEM, See OpenTopo article
• perform react-doctor by millionjs aidenybai millionco/react-doctor
• analyze react-scan results and recommendations, look for unwanted react components redraws etc
• tracker for compression support in geotiffjs [Tracker] for compression support in geotiffjs / Utifjs or sharp/jimp historical-satellite#38 and source update flicker (see if still problematic) Fix flicker of historical imagery historical-satellite#44

Some important Implementation choices

strava:

{
"id": "custom-basemap-1787928683294",
"name": "strava heatmap",
"url": "https://cors-proxy.mrgriscom.workers.dev/?https://heatmap-external-b.strava.com/tiles/all/blue/{z}/{x}/{y}.png",
"type": "tms",
"description": "",
"role": "overlay",
"opacity": 100,
"maxzoom": 11
}

• Real shadow-mapping (render depth from the light's viewpoint into a framebuffer, then compare per-camera-fragment) needs two rendering passes reading back a texture across tiles — that's not expressible as an independent-per-tile raster protocol. It would fit the custom-WebGL-layer architecture Phong/Matcap's "2D Fast" already uses (since those already read getTerrainData() live per frame for a different reason — camera-relative perspective). Concretely: a light-pass rendering an orthographic depth texture of the visible terrain from the sun's direction, then a camera-pass sampling that texture per-fragment (with the usual shadow-acne bias) — same tile-covering/get_elevation plumbing already built for Phong/Matcap, just two passes instead of one.
  It's a meaningfully bigger lift than the other "2D Fast" layers (multi-pass FBO management, depth-texture encoding, bias tuning) — roughly on the order of the Matcap 2D Fast build. Want me to go ahead and build it as a new custom-GL-layer "2D Fast" mode for Shadows, or hold off on that one for now?

• SVF Fast could be nice to try only 2 samples, 2px per octave ray marching to accumulate very fast even for 8px searching. Probably similar for openness. 

• OPFS don't seem to be fixed on import, same error, but at least now when I load the local COG it does not disappear, only disappears on reload on the other computer, could it be because of LAN IP? 

  • new layer in light visualization section: shadows, that would do hard-shadows with some opacity, projected from sun position / light direction azimuth/elevation. Also eventually another layer could be good, hours in the sun (better with vector tile source with buildings height, but could be nice with DSM / DTM), but probably postpone this one.

• LRM WMS vs TMS half-pixel — the recentering math is identical and correct for both; that was never the bug. What's different is that TMS/COG ancestors come from a real pre-built overview pyramid, while a WMS server resamples "live" for coarse zooms — often with a much cheaper/blockier resampler than bilinear. Fix: for the WMS-raw path only (regex-gated in lrm-protocol.ts), request the ancestor at a reduced size (rewriteWmsRequestSize, clamped ≥32px) and bilinearly upsample it ourselves client-side (upsampleDecodedTile) — bypassing the WMS server's own resampler entirely. Mapterhorn/TMS ancestors are untouched.

• Parallelization/thread count — not a real worker/thread count (browser tile compute for these modes is single-threaded on the main thread; only the network fetch overlaps). tile-timing-stats.ts instead tracks an empirical maxConcurrency: at every tile request it computes requestedCount − completedCount (how many are genuinely in flight right now) and keeps a running max. The "time remaining" estimate divides pending tiles by that observed concurrency instead of assuming everything is strictly sequential — that's what fixed the over-conservative estimate.

• while higher resolution tiles are loading for slow sources like SVF, Openness, Local Dominance, keep the lower resolution tiles, probably similar to what has been added to deckgl lod tiles pre-fetching here have a look at feat(geo-layers): coverage LOD tile prefetching visgl/deck.gl#10306. Possible cause:
  MapLibre placeholder-tile investigation — traced it into maplibre-gl-dev.js: cancelPendingTileRequestsWhileZooming defaults to true and cancels in-flight tile requests the moment you zoom past their level. For slow ray-marched modes, that meant the ancestor's expensive compute almost never got to finish before being canceled mid-zoom, so there was nothing valid sitting in the cache for maplibre's own (already generous, up to 10 levels) overzoom-placeholder logic to reuse. Setting cancelPendingTileRequestsWhileZooming={false} on the fixed it — a single prop, not the dual-source approach you ruled out.
  cancelPendingTileRequestsWhileZooming={false} does something narrower than it sounds: in maplibre-gl-dev.js's _updateRetainedTiles, that flag only stops MapLibre from aborting a tile it has already started tracking. It does nothing about tiles that haven't started yet.
  The actual bottleneck is almost certainly this: MapLibre runs all image/tile fetches (base map, hillshade, terrain elevation, and every custom-protocol analysis tile) through one global FIFO queue (ImageRequest in the same bundle). While the map isMoving() — which includes zooming — that queue's concurrency cap drops from MAX_PARALLEL_IMAGE_REQUESTS (16) to MAX_PARALLEL_IMAGE_REQUESTS_PER_FRAME (8), and a slot isn't freed until the request's promise resolves. A multi-second ray-marched tile (openness, local dominance, live Phong) occupies one of those 8 slots for its whole duration, and can also simply sit queued behind other fast requests during a zoom gesture, never getting a turn to even start.

Todo Next

• Other detectors, like standard blob intensity (just pick the layer you designed to have great visual blobs at their given user-controlled range bounds etc. Eventually voronoi cells diagram islands from tops local extremas above threshold.
• look at deckgl-raster and Kyle barron geotiffjs alternative
• Create Points at Highest and Lowest Locations: An additional analysis process in the contour creation tool identifies local high and low points by identifying a specified number of concentric, or nested, contours. Additional parameters stipulating a required minimum distance between identified spot heights can be added, but the peaks and depressions identified are based on the contour lines generated by Global Mapper
• Even more feature maps New feature maps, descriptors like shape index, LS factor, breaklines #15
• Raster Line detector - feed it a given feature-map render, Canny, Sobel, or even ridge detectors like skimage

Medium

• change detection between 2 COGs, no concrete usecase besides landslide open-data COG before-after, urban transformation etc, the data might be hard to find
• Vector tiles, probably only tilejson or style json, as overlays and basemaps): yes, feasible - MapLibre natively supports type: "vector" sources with .pbf tiles, and a TileJSON-based vector variant would parallel your existing "TileJSON (Raster Basemap)" pattern nicely. It's a bigger feature though (needs a layer/style picker, not just a URL field), worth its own turn if you want it
• make sure every component you want to reuse can live as its own eg ge historical imagery, custom slope protocol, WMS raw altitude terrain etc
• import configuration to qgis, with opacities per layer, terrain source, hillshade applied with same angles. Some cannot be done live like our slope or 1st/2nd roder derivatives or LRM? should we offer the user the ability to compute them for offline use from the loaded terrain dem source?
• can some of our custom protocols layers be ported to live qgis fetch and compute? Via VRT pixel compute python functions. The same way qgis decodes on the fly the raster tile source terrarium encdoig into raw elevation, would be great to compute these layers live.
• Export footprint and options via watergis/maplibre-gl-export see doc, shows PrintableArea, let user control format, dpi, page orientation, northIcon and marker styles, scalebar now supported see [FEATURE] Support scale control (and possibly other non-interactive controls) watergis/maplibre-gl-export#383
• Zero-shot change detection in-browser: Add zero-shot change detection / dino-v3 similarity via opengeos/geoai or decision-labs/geoai.js historical-satellite#33
• stockpile volume calculation 2.5D: let the user draw new polygon (at some point could even be launched for every feature of terradraw, but would be more precise if done at the current resolution. flat-out the polygon and measure volume over/under interpolated surface: chrome://flags/#touch-events — set it to Enabled, not the default Automatic. "Automatic" is a heuristic Chrome uses to decide whether a display exposes the Touch Events API at all, and it's exactly the kind of heuristic that can misfire on an unusual large-format digitizer like a Surface Hub's — forcing it on bypasses that guess entirely.

Ideas / To be discussed

Ideas / TBD

• Server-mode: Server mode: accounts, saved views + byod, trending etc #14
• SVF, Openness via GPU postprocessing compositing pass faster? Raster-source + screen-space post-process idea: render the depth or normal tiles as a real raster layer (inherits correct 2D/3D/globe positioning automatically, zero custom math), then a separate lightweight "2d" custom layer immediately after it in z-order grabs those just-rendered pixels (framebuffer copy) and does the matcap/phong math as a full-screen shader pass with live uniforms. Elegant and would also work everywhere for free, but haven't verified MapLibre's custom-layer render loop cleanly supports mid-frame framebuffer capture between two specific layers without other passes interleaving.
• Custom feature maps combination, linear combination weighted, to define advanced-user-controlled assemblage of indicators from terrain analysis or relief visualization.
• Dura dsm and see if can do geomatico fake geo
• Harden gpkg loading (in CRS other than 4326) via loadersgl or warn when wrong proj4 crs not 4326 etc, see Issues with polyfills and vite visgl/loaders.gl#2379
• eventually blue-green on cloudflare pages or vercel?
• while higher resolution tiles are loading for slow sources like SVF, Openness, Local Dominance, keep the lower resolution tiles, probably similar to what has been added to deckgl lod tiles pre-fetching here have a look at feat(geo-layers): coverage LOD tile prefetching visgl/deck.gl#10306. Possible cause:
• migrating icons, shadcn just introduced icons migration from to lucide, tabler, hugeicons, phospor, remixicons at cli#migrate-icons via pnpm dlx shadcn@latest migrate icons --from lucide --to phosphor --yes. Did icon migration via shadcn cli migrate, each on its own throwaway branch, but it only migrated the components icons. I also wanted to migrate my own app icons, currently lucide icons, attempt to do it? Maybe do a table of all lucide icons I'm using, with the suggested icons from tabler hugeicons phosphor remixicon, then apply them each in their respective branch so I can see?

Wont-do

• add overlay primitives geometry to hide unwanted areas like rc artefacts, or cog mask or no data clip or alpha
• add a layer tree organization structure for byod COGs, allowing user to do folders, collapse or expand etc on both terrain and basemaps/overlays layers.
• Probably not necessary: Mode simplified choose what stays in the sidebar in edit simple mode, useful for single slider or a few checkboxes on mobile in floating panel.
• not very useful, drag and drop import files (into terradraw section?)

Maplibre features (shaders) & bugfixes threads:

Maplibre features threads

• coachmark feature requests and bugfixes
• url-shorten with og:media: in social share, add switch to share as intent-url, the terrain-viewer url produced via url-shortener like dubco, passing OG:media as image url posted to imgbb or equivalent. dub-co feature request cors cross-origin missing and pass thumbnail to POST /links origin domain api [FEAT] CORS support for browser-based API calls dubinc/dub#3502 and [FEAT] Accept base64 image upload for image field on link creation dubinc/dub#3503
• xy grid resampling bilinear now in the spec, soon in gl-js Implement resampling paint property to raster, hillshade, color relief layers maplibre/maplibre-gl-js#7154
• z quantization terrarium follow Support for terrarium encoding geomatico/maplibre-cog-protocol#25
• Design Proposal: Color terrain by normal-derived attributes: slope, aspect, curvature, matcap, etc maplibre/maplibre-style-spec#1374
• Feeding maplibre-contour any raster-dem source type, not only TMS, eg COG streamt via @geomatico/maplibre-cog-protocol onthegomap/maplibre-contour#434
• MAPTERHORN: custom stac terrain sources catalog, with footprint, Web-map-link extension or cog, or country isoa3 or regional and ingest stac, or Nextgis-QMS equivalent like terria catalog stac editor stac-manager
• eventually offer other projection types like equal-earth, on hold while lands live in maplibre see recap Custom coordinate systems: Client Side Map Reprojection maplibre/maplibre#491 (comment)
• Maplibre Overview tiles low res low vfov already exposed here Low resolution tiles loading with low VFOV (<=10°) and high pitch maplibre/maplibre-gl-js#7146
• Add a raster-dem WMS float32 raw-elevation geotiff source support maplibre/maplibre-gl-js#7127
• Maplibre hillshade elevation uint, shows steps vs hypso which does work color gradient when only one meter 10cm bounds range

Todo long-term

• check unwanted redraws eventually extract map component from terrain-viewer like control panel is (all nuqs compatible)
• probably deprecated, BYOD MosaicJSON (buid mosaicjson with CLI cogeo-mosaic/cli, see archival notice + useful notebook)

Instructions

Animation rework instructions

Currently, I've got a react-map-gl maplibre app, with control-panel which expose an animation section with CameraButtons. These buttons let me set play360 play/pause, as well as set pose1, pose2, and play/pause animation and scrub via timeline slider. It's not very maintainable, and I want the given requirements :

• animationDuration, loopMode, should be controlled by nuqs url query-params (currently duration is part of animState, it should not otherwise i cannot edit/update duration after setting psoes)
• playing for keyframe animation, and playing360 would also usefully be url-controlled by nuqs
• resolution, fps, render quality should be controlled by atoms with storage
• ideally, pose1, pose2, should live in url as well, probably compressed, eg base64 encode/decode to avoid overflowing url length
• i want 2 modes, one smooth, smoothCamera (also url controlled by nuqs) which would only interpolate camera pose, and one complete, which would also interpolate every other state variable, mostly numericValues, like opacities etc. but using nuqs shallow mode, to not propagate to url
• in addition, there are some local state variables, like elapsed (only elapsed ?)
• if I close and reopen the sidepanel, I want to still be able to clear raf by pausing anim.

Actually want to store deltas only between pose-1 and pose-2, so no-need to compress.

[jo-chemla]

See up-to-date guide over here

Complete DSM & RGB Processing Guide

1. Check current resolution

gdalinfo input.tiff | findstr "Pixel Size"

Shows your actual pixel size (e.g., 0.0005m = 0.5mm for photogrammetry data)

2. Calculate scale factor

• Real GSD: 0.0005m (0.5mm/pixel from photogrammetry)
• Target GSD: 2m/pixel (chosen for web maps)
• Why 2m? Web Mercator at zoom 20 has ~0.15m/pixel resolution at equator. Using 2m/pixel is conservative and works well across zoom levels 15-20. Could as well be eg 20cm or 0.2
• Z-scale factor: 2m ÷ 0.0005m = 4000 (multiply z-elevations by 4000 to compensate xy rescaling)

---

DSM Command (Elevation Data)

gdal_translate -of COG -a_gt 0.01 2.0 0 -0.01 0 -2.0 -a_scale -4000 -a_nodata nan -co BIGTIFF=YES -a_srs EPSG:3857 -co BLOCKSIZE=256 -co TILING_SCHEME=GoogleMapsCompatible -co RESAMPLING=BILINEAR -co OVERVIEW_RESAMPLING=BILINEAR -co COMPRESS=DEFLATE -co PREDICTOR=3 -co OVERVIEWS=IGNORE_EXISTING -co ADD_ALPHA=NO -b 1 -colorinterp_1 gray DuraEuropos_Synagogue_W_0.5mm_DSM.tif
f DuraEuropos_Synagogue_W_0.5mm_DSM_fakegeo-3.cog.tiff

DSM Parameters:

• -of COG - Cloud Optimized GeoTIFF (web-optimized with internal tiling/overviews)
• -a_gt 0 2 0 0 0 -2 - Geotransform: origin (0,0), 2m pixels, no rotation
• -a_scale 4000 - Multiply z-values by 1000 (compensates 2mm→2m pixel scaling)
• -a_nodata nan - Numeric nodata value (RC uses NotANumber as NoData)
• -co BIGTIFF=YES - Handle files >4GB
• -a_srs EPSG:3857 - Web Mercator projection
• -co BLOCKSIZE=256 -co TILING_SCHEME=GoogleMapsCompatible - Recommended by geomatico/maplibre-cog-protocol
• -co RESAMPLING=BILINEAR -co OVERVIEW_RESAMPLING=BILINEAR - Average resampling respects nodata for base tiles and Average for pyramids (prevents nodata spread in overviews)
• -co COMPRESS=DEFLATE -co PREDICTOR=3 - Lossless compression (preserves elevation precision), float elevation requires predictor 3 for continuous elevation data compression
• -co OVERVIEWS=IGNORE_EXISTING -co ADD_ALPHA=NO overwrite overviews, don't add alpha
• -b 1 - Extract only elevation band (drop RGB+Alpha if present)
• -colorinterp_1 gray - Mark as grayscale elevation (required for hillshade to work)

Choice of AVERAGE vs BILINEAR or other for DSM? AVERAGE resampling properly excludes nodata pixels from calculations, preventing nodata from bleeding into valid elevation data in overviews. But results in poorer grid like structure in the data

---

RGB Orthophoto Command

gdal_translate -of COG -a_gt 0.01 2.0 0 -0.01 0 -2.0 -co BIGTIFF=YES -a_srs EPSG:3857 -co BLOCKSIZE
=256 -co TILING_SCHEME=GoogleMapsCompatible -co COMPRESS=JPEG -co QUALITY=95 -co RESAMPLING=BILINEAR -co OVERVIEW_RESAMPLING=BILINEAR -co PREDICTOR=2 -co OVERVIEWS=IGNORE_EXISTING -co ADD_ALPHA=NO DuraEuropos_Synagogue_W_0.5mm_RGB.tiff DuraEuropos_Synagogue_W_0.5mm_RGB_fakegeo.cog.tiff

RGB Parameters:

• -of COG - Cloud Optimized GeoTIFF
• -a_gt 0 2 0 0 0 -2 - Geotransform: origin (0,0), 2m pixels, no rotation
• -co BIGTIFF=YES - Handle files >4GB
• -a_srs EPSG:3857 - Web Mercator projection
• -co BLOCKSIZE=256 -co TILING_SCHEME=GoogleMapsCompatible - Recommended by geomatico/maplibre-cog-protocol
• -co COMPRESS=JPEG -co QUALITY=95 - Lossy compression (better file size for imagery) + JPEG quality
• -co RESAMPLING=BILINEAR - Smooth interpolation for base tiles
• -co OVERVIEW_RESAMPLING=BILINEAR - Smooth interpolation for pyramids (prevents artifacts)
• -co PREDICTOR=2 -co OVERVIEWS=IGNORE_EXISTING -co ADD_ALPHA=NO

No -a_nodata, -colorinterp, or -a_scale - Not needed for RGB imagery

---

RGB with Alpha Channel (RGBA → RGB with mask)

If your orthophoto has transparency (4 bands):

# Be careful, command not tested
# gdal_translate -of COG -co BIGTIFF=YES -co COMPRESS=JPEG -co QUALITY=85 -co RESAMPLING=BILINEAR -co OVERVIEW_RESAMPLING=BILINEAR -b 1 -b 2 -b 3 -mask 4 -a_srs EPSG:3857 -a_gt 0 2 0 0 0 -2 input_orthophoto.tiff output_orthophoto.cog.tiff

Additional RGBA parameters:

• -b 1 -b 2 -b 3 - Select only RGB bands (drop alpha)
• -mask 4 - Convert band 4 (alpha) to internal mask (prevents transparency issues in overviews and allows JPEG compression)

Why drop alpha for JPEG? JPEG doesn't support transparency. Converting alpha to an internal mask preserves transparency information while allowing JPEG compression of the RGB data.

[jo-chemla]

Done

Major features recently added

• weird hq terrain terrarium vs terrainrgb in geomatico
• toggling hillshade off in 2d crashes the app
• nuqs parseAsColor Add support for `parseAsColor` 47ng/nuqs#1342
• hypso slider step could be 100 values always, or closest count that implies decimals that are pow of 10, via log10
• hillshade exaggeration defaults to 0.5, but does not seem to be why basic and multidir appear too bright/burnt
• terrain in 2nd map in split mode is broken
• reorder cpt2js color-ramps discrete vs continuous
• make anim options export atomWithStorage's
• could remembering scroll position in sidepanel be useful ?
• keep xypad for only azimuth and set fixed elevation
• Mobile mode, via transparency non-active sliders
• Result of searching useState in whole repo to set other state vars via jotai atomwithstorage or nuqs url query state : could do so for minimap-minimized
• Terrain not always loading
• Dawing tools not always initializing/appearing
• Export video WIP is laaagggggy solved via MediaBunny, and fallbacks to WebCodecs and MediaRecorder
• Minimap react map gl nice buttons from comments, recover dynamic, zoom offset, bounds footprint, raf pause,
• Share mobile ios and macos not working
• Get elevation to auto set hypso slider bounds, see hypso if does this
• 2d circle control for light position illumination angle and elevation, eventually fixed elevation like slider circular
• reorder panels and default opened panels
• Cam pose 1 to 2 simple traveling
• animation duration (or speed via checkbox switch), a timeline slider, and a checkbox to loop animation, or rather select to loop none, forward or bounce
• Share intent mobile for slack etc
• minimap wip
• TerraDraw, import geojson
• explode
• import kml, wip gpkg
• copy snapshot to clipboard
• share to socials via intent url, text and copy paste to clipboard x bsky threads mastodon etc
• Copy snapshot as well as post to socials with base64 encoded, twitter mastodon bsky maybe expandable button or modal
• Explode Extract contour layer like graticule layer
• Fix Layer ordering via slots layers when editing maplibre style, basemaps etc
• geogrid working and updating correctly
• terradraw opacity
• wip animations like 360, pose1-pose2

Quickfixes

• make top of sidepanel stick to top, useful for mobile
• byod basemap and byod terrain buttons overflow
• no, dont do that eventually add more backdrop to div with slider to have it more prominent
• colorramp tabs could be standard shadcn tabs rather than buttons
• cannot pinch to zoom in 2d on mobile
• make mobile backdrop transmit events so one can pinch to zoom and close sidebar at once.
• Dynamic Viewport Height issue for mobile, minimap control not always appearing when chrome android url bar appears

[jo-chemla]

Major features implemented

Nouvelle passe : Basemap side split view, slope v2 custom protocol donc adaptée à la rzoslutiol de la source de terrain eg byod cog, et Tilejson raster basemap

• slope v1 streamt from plantopo slope-server
• terradraw drawing points, polygones etc cannot be exported and do not count in the features count.
• Basemap in side split view, or button to tell in which map the settings do apply. Probably in both standard and split mode, at the top of basemap source section, left-aligned of source label, we could have a toggle switch to control per-view basemap. When off, same feature set as today, a select to select sources, and the list of custom basemap sources in its own foldable section. If on, that mode would remove that basemap select and replace it by the basemap sources with radios (single sview) or A|B toggles (split screen mode), exactly like is currently done for terrain sources.
• slope v2 custom protocol Slope from plantopo tiles slope-server or maplibre custom protocol #8
• Allow for Tilejson raster basemap and simplify TMS, COG, WMS etc pure maplibre or through titiler for basemaps and terrain, maybe factorize url definition and source definition given a source type
• add colormaps from rfspace which are reall nice. There would be a lot of tabs in the hypso colorramp type selection, so have this in mind, eventually make the tabs horizontally scrollable.
• export contours vector static file see Add abililty to export via API raw contour lines vector onthegomap/maplibre-contour#432 probably via queryRenderedFeatures map.queryRenderedFeatures({ layers: ['contour-lines'] })
• Also the custom protocol for wms wmts should encode as terrarium rather than terrainrgb for 4mm vs 10cm precision - for both terrain-viewer and the mini demo poc app for IGN.

Done last batch

• composite layer for dura into single cog or multiple layers
• Add Re:Earth Terrain see repo and template but this is roughly just Mapterhorn minus geoid-vs-ellipsoidal height https://terrain.reearth.land/terrarium/ellipsoid/{z}/{x}/{y}.webp
• no need to patch geomatico a scale and maplibre linear gl instead of nearest
• download button spins
• edit gdal_translate command to include convert encoding to raw altitude DEM
• add note to say where to find gdal, ogeo4w, qgis, conda etc
• duplicate source name on byod basemaps. Check with distinct ids if zoom autofit works
• add mapterhorn in inspiration, add suggest new terrain source to mapterhorn or terrainrgb
• make play360 nuqs state
• TBD: switch theme from jotai storage to nuqs url
• make sure there are no better oss geocoders
• find the right command for DSM with rescale, fakegeo, nodata propagating large pixels overviews, band interp gray, 1 band, alpha. SEE BELOW comment and try to generalize, and add projects
• auto elevation cannot be set on mobile, nor mac, or 2d Uncaught TypeError: can’t access property “getAllIds”, Ae is undefined
• try finding/experimenting with WMTS/WMS: sources of true elevation, not precomputed hillshade color-encoded
• edit vanishing point padding when sidebar open
• See more, RTI-like, longer-term, here [EPIC] Terrain Elevation Viewer Ameliorations (hillshade etc) historical-satellite#54
• Won't-do: Lens via css clip path with synced dom divs

Other batch

• animation bug when closing sidepanel, state kept but cannot pause
• Rework the whole animation state, local etc see instructions below: make animation state (pose1, pose2, play, 360) vars nuqs ready. uqs store compact compressed anim state Ways to compress url search query for animation (repeated state complex json object) 47ng/nuqs#1343 [ ] min max zoom for source not set on load only on layer switch, and map zoom not set depending on source
• when nuqs state url shows query pitch = 0.000, then switch to 3D or globe view, with mouse i cannot use the mouse right click to edit pitch, I'm locked in top down view
• check anim play360 (state, sidebar collapse/expand, stop), and pose1/2 deltas editing some variables after poses set, and setting another pose.
• bounds of slider should accept only minus, without showing nan to validate
• set max zoom source on ign wms example to 17 (both single html poc app and terrain-viewer sample-data IGN)Yes commit these changes.
• Batch edit custom byod sources json and API key batch edit : use syntax highlighter

[jo-chemla]

Features

• Expanded curvature & terrain-analysis suite — Profile/Plan curvature, TPI, Roughness, Det-Hessian, Blobness structure-tensor, auto-scaled ranges per mode.
• Local COG (BYOD) terrain sources — pick a .tif off disk, no upload, with CRS/tiling validation.
• Basic / Advanced mode toggle — Terrain Analysis and Relief Visualization sections collapse to just checkbox + opacity slider, hiding sub-mode options until wanted.
• Local Relief Model (LRM) — multi-scale relief mode isolating local bumps from the regional trend.
• Sky View Factor & Openness — new horizon-angle-based visibility modes.
• Archaeological mound detection ("Tells") — experimental detector flags candidate mounds from curvature/blobness; own section, color-by ramps, export, explainer, beta toggle.
• Keyboard shortcuts — Shift-tap to peek at the raster basemap; Ctrl-tap to hide every overlay down to just the basemap, tap again to restore.
• More data sources — PlanTopo slope overlay, TileJSON, CET/SDR ramps, NextGIS QMS search, WMS-raw, Photon geocoder.
• Labeled sidebar dividers — Sources / Options / Detectors / Tools section breaks for scanning a long control panel.
• Same source on both A/B — split-screen source pickers only ever showed one side as selected, even when both used the same source; fixed to show both independently.
• Elevation Picker — now shows distance between points and decimal lat/lng.
• Camera/animation pose rework — URL-shareable camera state; Home now correctly resets saved poses.
• Higher-precision terrain-derived tiles — curvature, aspect, TRI, roughness, openness, blobness, and LRM now wire-encode ~25x finer, cutting visible banding.
• Client-side DTM export & project embed system — export GeoTIFF from the browser; per-project embed/URL config.

Bug Fixes

• TerraDraw: init race, GeoJSON import double-counting, Fast-Refresh break.
• Minimap: cold-start delay and resize bug.
• TypeScript errors cleared to zero.
• Sidebar scroll/header glitches — corner-rounding squaring off, button group shifting, fast-scroll jitter.
• Overlays ignoring their own max zoom — hardcoded limit overrode a source's real tile pyramid (e.g. NASA GIBS), causing tile-request errors.
• 2D Elevation Picker freeze on large COG files.

Final batch

• allow passing project id or terrain or basemap url, in which case terrain and basemap sources and byod should not be shown. Probably only for cog if urls via search params, structured sources for project id. This would be to isolate eg the dura terrain and dura rgb, no more need to have sources, only some panels, remove globe, Test with https://terrain-viewer.iconem.com?project=mapterhorn-globe and https://terrain-viewer.iconem.com?project=dura
• raw WMS with eg https://data.geopf.fr/wms-r?SERVICE=WMS&VERSION=1.3.0&REQUEST=GetMap&LAYERS=IGNF_LIDAR-HD_MNS_ELEVATION.ELEVATIONGRIDCOVERAGE.LAMB93 could we have a helper to build the whole url with style and what is needed by the server ? If the user enter a complete WMS raw string already correct, great take it as is, if he takes a standard WMS url, add a search box to searh in layers, wms layers list, and build the url from the user selection? That would be a big one.
• some byod custom basemaps can be useful as overlay rather than basemaps, on top of another basemaps (and eventually multiple overlays). Add a toggle in basemap source modal (new or edit) to let user choose between basemap/overlay, again probably a button group pill rather than toggle. Overlay layers would make sense only in mode split-or-radio of basemaps, not with the select simplified mode. Overlay layers would probably be in a custom section of byod basemaps, with checkbox list rather than radio cause multiple can be selected. When selected this time it would not change the basemap, in both split and non split modes, it would just be added over basemap.
• Custom protocol Design Proposal: Color terrain by normal-derived attributes: slope, aspect, curvature, matcap, etc maplibre/maplibre-style-spec#1374 like slope, but for aspect, terrain ruggedness, curvature + Potential starter (probably more complex than our implementation)
• mapbox-gl-elevation to get elevation at cursor or height difference Z+XY
• Local or relative depth vs controllable neighborhood, like diff of gaussian, could even do Relative elevation model via polyline tracing auto or manual. DONE AS LRM, and also see http://github.com/iconem/riverREM_UI/

Post Final batch

• export contours merged polylines and all geometries present, eventually datatype other than geojson because easily 10+MB
• probably not fixable: when loading the app, the terrain is set to 3D mode/globe only after all tiles in viewport have loaded
• Reinstated MediaBunny → WebCodecs → MediaRecorder. MediaBunny was working in an earlier commit (69c3efe), got fully ripped out in a later refactor (93cbc77). Nothing else ripped out like MediaBunny after listing carefully
• Local COG stream
• SVF / Openness
• Reorder Terrain Analysis (Derivatives, slope, aspect, curvature - profile plan div det hess - TPI TRI roughness etc) and Relief Visualization (LRM, SVF, Openness)

Post post final batch

• Reuse the raster-dem source generically for COG in slope/aspect/TRI/curvature, the same way hypso re-uses the raster-dem terrain source without reinventing the fetching logic. The normal-deried protocol can be used the same way hypso calls geomatico cog-protocol, call the wms custom protocol for eg ign MNS ELEVATION GRID COVERAGE sample.
• TerraDraw: Multiple drawing layers, each colored differently, eventually every imported vector file gets into its own layer. A single layer can be edited at the same time, all can be restyled.
• Make all meta sections (Sources, Options, Tools, Detectors) also foldable or Move Tools into another sidebar?
• ? light control in the viewport (pressing shortcut key L)
• Persist local COGs to OPFS Persist Local COGs via OPFS/IDB across session to avoid needing reuploading #12
• Persist local vector layers the same way we persisted local cogs to OPFS
• Give information about the underlying composited source:
  • aws terrain read the tiles x-amz-meta-x-imagery-sources metadata (the S3 mirror preserves the old X-Imagery-Sources header as object metadata)
  • Mapterhorn provenance: fetch https://single-archive-tiles.mapterhorn.com/coverage/{z}/{x}/{y}.mvt → read each feature's source code (e.g. glo30) → join to the matching source entry in attribution.json for dataset name, producer, license, and native resolution.
• COG + contours: find a way for contours plugin to read tiles from COG geomatico/maplibre-cog-protocol? I assume the custom protocol geomatico build exposes a tms url template /z/x/y which would be transparent to contours
• Lighting Matcap like spheres protocol, and normals ? With 2D circle xypad selector for light direction? (or not)
• Lighting Phong with live edition of light direction, cotntribution of fiffuse, specular and albedo reflections, light position in absolute vs camera screen space
• Plane Slicer above/below Z in absolute or LRM altitude
• Custom colorramp stops, continuous or discrete, set colors and stops
• Faster Local Domainance based on pyramid octave 1px, 2px, 4px etc
• custom theme selector and advanced theme editor, randomizer etc
• Routing:
  • BRouter Public API: brouter.de/brouter?lonlats=lon,lat|lon,lat&profile=trekking&alternativeidx=0&format=geojson: the gold standard for bikepacking/hiking. Elevation-baked, richly tunable profiles (trekking, gravel, mtb, hiking-mountain…). → GeoJSON you can drop straight onto MapLibre. Trivially self-hostable. My pick for bikepacking.
  • Valhalla (public valhalla.openstreetmap.de): excellent all-rounder: pedestrian + bicycle (with bicycle_type: mountain), elevation, turn-by-turn, isochrones, map-matching. Stable public endpoint (fair-use). My pick for hiking + turn-by-turn with no setup.
  • GraphHopper: solid hike/bike/foot profiles with elevation; polished hosted API but needs a key (freemium, limited free requests). Self-hostable OSS.
  • OSRM: fast but car-centric; foot/bike profiles exist yet it's not elevation-aware and profiles are rigid. I'd avoid it for trails.

[jo-chemla]

Did

• Probably everytime there is both checkboxes invert colorramp and symmatric range, both controls checkboxes and labels could be on the same flex row, 50-50 I've dont this for most.
• Hillshade shadow/Highlight colors, could you put on a same line flex 25% each the label shadow, color (no border, would resemble terradraw Layer fill color input, small square with rounded corners. Extract out ColorAlphaSwatch from TerraDrawSystem.
• The tooltips on Relief Viz, Terrain Analysis, Light sub modes, when they are hovered they should disappear, and only be visible when the user hovers the label itself - so it does not hide the underlying controls, or prevent the user from hovering another mode to understand what the other mode is about. Also tooltips on download buttons, source side right aligned buttons, source name label
• Background section should should be in options meta section group, just below Lighting effects, above detectors / Mound candidates. Also a row is missing between terrain analysis and lighting effects sections
• Hillshade XYPad also add the phong datepicker and mode free vs datetime. copy component and state from \components\TerrainControlPanel\lighting-effects-options-section.tsx line 350 to \components\TerrainControlPanel\hillshade-options-section.tsx lines 79, make it a single state lightUseDatetime rather than phongLightUseDatetime and lightDir, dayRange, probably abstract it into its own component.
• Local-Dominance should also include symmetric colorramp.
• add reference to riverrem webapp link
• Plane slicer height number input should react to up/down arrow keys for +1/-1

Then

• new keyboard shortcuts: Ctrl + K for geocoder search go-to
• umami track events for source change, viz-modes used and options, tools etc
• allow cancelling downloads dtm, when the spinner spins, hover should display Cancel and clicking it should cancel the download, assemblage of geotiff etc
• auto set elevation bug when too high zoom, should be clamped
• bug with IGN WMS DSM, when displaying matcap: Error: sources.matcapSource.maxzoom: number expected, undefined found
• In Plane Slicer, there is an option to choose elevation whether it slices absolute altitude Z, from source, or LRM relative elevation. Please add the same control to CONTOURS and ELEVATION picker. and also let the user choose which elevation (absolute or LRM) in contours source
• Make other color pickers look like terradraw layer color picker, square rounded corners (contour / geogrid colors, place slicer color, background sky/horizon/fog colors, hillshade accent color, maybe also the draw layers color pickers when editing, with 2 colors for fill/stroke colors)
• offer custom colorramp stops colorramp to all viz modes colorramps, not only slope.

Then

• Frescoes terrain + albedo, add link chain cross-link icon to indicate when one is connected (source terrain or raster) the other will auto be selected, can be connected in source modal, select to choose the alternative list?)
• feature iterator in terra draw modes: show a toggle to activate that mode, which would tap into a layer (chosen via select? or clicked after in the flow? or have a loop through icon lucide next to layers name? ), show an index 1/126 starting at one of feature id you're looking at over how much total in the layer, with next/prev chevron left/right buttons, the index being a number input that can be set to another index for go-to, which auto-zooms on a feature (if shape polyline/polygon with a small screen space buffer like 20%), centers it on frame if point, at given map-zoom (controllable by user, or keeps current zoom untouched if zoom is set to nothing (with button to set to current zoom))
• for slow sources like SVF openness Local-dominance, evaluate time to fetch and compute all tiles. reset when user moved, and add indication of remaining time based on known compute time of already rendered tiles
• bookmarks viewport and viz modes full nuqs state, save to local storage the states values and thumbnails, like river rem gallery either sidebar 1 column or fullscreen gallery 3 columns. Eventually hierarchy, viewport top post and viz modes under it save restore delete etc and full import export. RiverREM_UI/.../GalleryModal and RiverREM_UI/.../SidePanel
• WMS IGN half-pixel error: seems the LRM compute the pixels from fine resolution native and octave/pyramid level, the pixel don't overlap which introduce weird artifact ike butte monmartre is white/black rather than one white over grey. Like we are evaluating pixel corner rather than center of low resolution. See eg this example
• The sidebar footer with made-by, also-see, inspired-by, make it cleaner, and foldable like other sections, although less pro-eminent title.
• cog streaming settings (maplibre/titiler), make sure that setting defaults to maplibre in localStorage, right?
• In settings modal, reference Geomorphometry Scientific Literature and Tools resources section with links to whitebox-tools terrain-analysis and wayback archive with screens and GeoMorphoMetry proceedings 2020 and 2025, as well as LSP Calculator parameters, see source code
• New feature maps like PCA-based, shape index, casorati curvature
• eventually this is the source for map layer desync vs react nuqs state: desync comment quickfix
• geocoder catch parse decimal degree (eventually with pos/negative sign or NWSE suffixes, and DMS)

Then

• pinch-to-zoom on touchscreen should zoom to pinched area rather than to center of the viewport. It does so on mobile android smartphone and chrome on surface-hub hub 2D or GLOBE projections, but not for 3D projection? chrome://flags/#touch-events has to be ENABLED
• Import / Export whole project, with BYOD terrain/raster basemap+overlays sources, bookmarks, local stotage drawing layers, localStorage jotai atomWithStorage config settings. Eventually have checkboxes expliciting what can be exported, default check all but settings.
• Make Phong / Matcap faster Phong/Matcap 2D Fast in 3D terrain draped mode #13 , custom protocol has to produce tiles blob images that maplibre hands to gpu, but we should instead see if posssible to do custom layer with webgl shader for live uniform passing and live edition.
• Make Light Phong / Matcap light direction anchor be either absolute in world space or attached/relative to camera. Now both Phong and Matcap also ship a 2D fast webgl2 mode (matcap seem to correctly react to drag translate pans the diverging rays from cam ray), could you re-enact re-enable the light attached to global absolute coords vs light relative coordinates? So it reacts to viewport altitude/elevation to compute the reflected rays? 
• Bookmarks when any parent is saved to bookmarks, save the viz mode as its first child. 
• new layer in light: hard shadows projected from sun position / light direction azimuth/elevation. Also eventually hours in the sun (better with vector tile source with buildings height, but could be nice with DSM / DTM). Would love that hard shadows be as interactive as phong or matcap, 2D fast vs 3D slow and accurate? Is there any way to make it 2D Fast by taking some assumptions? That shadow layer, would there be a way to render depth from the light viewpoint, and use that as a depth test whether the point visible in camera screen space depth is visible from light or not comparing its depth to light ith the screen space depth buffer of the geometry rendered from light voewpint?
• Add a new tool sun shadow length calculator? would include date and time slider pickers from hillshade/phong (+ date / time inputs), hover dom elements probably, like suncalc or shadowmap, height input, or could also let the user draw two points to find closest light direction angle at date (to find time and height at the same time)

Then

• shadcn Radix -> Base UI migration: pnpm dlx skills add shadcn/ui, Then ask your coding agent: migrate accordion to base-ui.
• Massive dependency cleanup, github action workflow file fix, dependency version locking etc
• insert react-scan by millionjs
• bookmarks, allow folding the bookmarks children, almost like a file layer tree. Probably the parents should actually not have a thumbnail, but just the bookmarks group folder label/name, delete and add buttons, viewport naming hierarchy, and only the children would have the thumbnails, names etc etc
• pickers for elevation and sun shadow prevent being toggled on when user draws some points and toggles back select, cannot select other pickers after closing or after having drawn, like select state is not correctly remembered. User has to select a feaure on the map for that select mode active to allow the pickers to be toggled on.
• in basemap/terrain edit source modal, copy-pasting /{z}/{x}/{y} into the url field gets url encoded, but user can write the braces by hand. These should stay as braces, not url-encoded. Could also be nice a mini icon button next to zxy template to copy the template,
• esri max-zoom is wrong, it has to be user-controllable in byod basemaps like it can be for byod terrain. Make sure the maxzoom for non-byod basemaps is correct, get inspired by https://github.com/Iconem/historical-satellite/blob/77ec155c66797cd81c44c64697bc0863cc558ead/src/utilities.tsx#L159. Also add in standard basemaps make sure all layers from historical-imagery are here, might be missing Bing https://t.ssl.ak.tiles.virtualearth.net/tiles/a{quadkey}.jpeg?g=14603&n=z&prx=1, ESRI https://server.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer/tile/{z}/{y}/{x}.jpg,google sat and hybrid and if env keys present, Mapbox, Heremaps https://maps.hereapi.com/v3/base/mc/{z}/{x}/{y}/png8?style=satellite.day&apiKey=${HEREMAPS_APIKEY} https://api.mapbox.com/v4/mapbox.satellite/{z}/{x}/{y}.webp?sku=1018anLugHFK1&access_token=${MAPBOX_TOKEN}
• umami events I've got too much, 100k monthly events limit, seems most are options-relief-visualization that just tell me svfPrecision and opennessPrecision precise. I don't care about this one disable it, and there is probably an unwanted redraw occuring if this is the only event firing that much.
• always display basemap source section, like terrain, not only when raster basemap toggled on
• Finally, could you do a feature matrix, and explicit what viz-mode is not supported by what terrain-source in a matrix (terrarium terrainrgb for all, wms and the others subset). At some point we'll want to make the important features like contours, elevation picker and profile etc also work for byod COG, WMS, not only TMS terrarium/tetrrain-rgb, and make sure titiler is not always necessary. Feature parity matrix done, and next-steps explicited in plan over here Feature matrix: Elevation source types vs Features + TiTiler case #16
• SVF Fast could be nice to try only 2 samples, 2px per octave ray marching to accumulate very fast even for 8px searching. Probably similar for openness. EVENTUALLY DEPRECATE THE FAST SVF/OPENNESS MODES? SVF and openness, can they also take advantage of tiled hierarchy pyramid octave, looking at 1px in fine resolution, 1px in 2x, 4x, 8x resolution, like fast Local-dominance? Might be less precise, offer both options in toggle fast imprecise or slower precise?

Then

• export project, bookmarks also exported with base64 blob screens inlined in json. For zip, could place them under a bookmarks_thumbs subfolder of the zip, and point to these relative paths so not inlined in json if zip exported (so if local-cogs selected). Should be detected on import that these use relative paths for bookmark thumb. Also, local-cogs could be place in local-cogs zip folder rather than root.
• probably due to devicePixelRatio=1.5, not fixable. separator between section below sun shadow seem to be thick bold
• looks like some toggles like keyframes complete-vs-smooth are custom, could use default (small size)
• Also add count of local byod cog sources in export modal
• shadcn ui radix-to-base follow-up: SEE THE STYLE MIGRATION TO BE PERFORMED AS WELL BELOW IN DETAILS FOLDED BLOCK
• terradraw export currently flattens all layers features, probably keep their property id which would trace back to original layer. Could be good offering the option to toggle with the other option, to do one-geojson-per-drawing-layer multiple geojsons downloads (or one zip), with nice flow flatten all layers so new drawings get in same final output layer (current flow)
• allow any colorramp to be edited (in hot session, not persisted to local-storage or nuqs. Also any colorramp could have a toggle, black/white is transparent that would edit that color on the ramp to transp.
• change favicon depending on prod terrain-viewer.iconem.com vs local dev vite 5173, make it purple for dev, keep current blue for prod
• make geocoder an expanding search, so it only shows the search icon, until it is clicked and expands. Once text is inside the geocoder (search or result), it should stay expanded. Also keyboard shortcut Ctrl+G should expand it. like on interior-dev
• <Select> Left/Right arrow-key cycling
• make maplibre controls icon buttons match theme background/font primary colors, light/dark theme, border-radius, as lucide svg rather than background-image
• when toggling off/on some layers, seems they are not cached, like openness/svf visible for slow ones.
• unwanted map layer redraws, probably for light layer phong/matcap, tiles unloading reloading on some layer modes like light phong etc, maybe since refacto
• geocoder micro thing missing: once a result is selected, the cross clear icon is not visible until hovered, then become visible but background/font colors do not match theme.

[jo-chemla]

• walkthough guided tour and complete docs (to be amended)
• Historical imagery (beta option dans les settings for now, je vais surement le sortir de la beta)
• appMode historical vs terrain for different sections/viz modes options
• grid N-views (2x1, 2x2 up to 4x2) sur
• split can now be overlay or side, with blend modes
• toutes les historical google/esri wayback etc sur une seule timeline,
• histogram matching
• bookmarks, featured and gallery, etc

Download without titiler, Shadow estimator

• Add a download mode independent of titiler, based on geomatico, or iconem/river-rem-ui, which would allow larger exports. https://github.com/Iconem/RiverREM_UI/blob/main/frontend/src/lib/remClient.ts. Check max resolution possible with this for both cog dem but also png snapshot.
• BYOD Custom WMS or WMTS (eventually WMTS-t temporal) with template {bbox-epsg-3857} like so tiles: ['https://img.nj.gov/imagerywms/Natural2015?bbox={bbox-epsg-3857}&format=image/png&service=WMS&version=1.1.1&request=GetMap&srs=EPSG:3857&transparent=true&width=256&height=256&layers=Natural2015'] again can be a simple simple input in modal with helper description. Let the user enter the correct input
• Closed form sun-direction to UTC datetime (doy/tod) equation and inverse problem + graph #17 Shadow length estimator: Allow user clicking on XYPad in datetime mode and find back corresponding day-of-year/time-of-day, reverse the equation. XYPad, display the range of available sun positions throughout the year and day start/end (explicit mathematical form or rasterized?).
• ill-posed problem infinite solution counts, Sun shadow estimator. Set doy/tod by letting user set object height, clicking on the satellite imagery the base-point and shadow-tip, and compute the light-direction and infer doy/tod. Can add building height if known to solve last unknown and find datetime.

Historical and Grid overlay

• integrate Historical-Satellite subset feature-set: Google Earth Historical Imagery Timelapse reversed repo and demo + ESRI wayback machine via js wayback-core sdk and timeline. Add a new basemap source, "Historical basemap" (like google, bing etc, that can be set as radio split mode off or A|B button group for split mode on), that aggregates all historical time images like esri wayback and google earth historical (could be selected which historical collection to account for by pill on top of the timeline panel at the bottom). if historical source mode is activated, see mockup for a bottom timeline component panel, historical-v2 UI redesign v2 mockup : SidePanel for Layers and BottomPanel for Timeline historical-satellite#30 See historical-imagery control-panel as well as see below screen
• unique-timeline, with ticks the imagery dates (not layer dates but real imagery dates via WMS query for esri, you'll discover later) for esri-wayback, google-historical etc, Aggregate multiple historical sources on the timeline (google, esri wayback etc) historical-satellite#61 at some point it might make sense to aggregate esri wayback, google earth time machine historical imagery, or any high-resolution temporal raster basemaps on the timeline - could also do with maxar/planet dynamic basemap queries via cql filters. This could be a new source, Aggregate (planet, bing), eventually user filterable. Filters could include resolution, or which source do participate in the aggregate, VHR, MEDIUM etc so one can display google HD 30cm vs planetscope 3m at the same time, eventually encoded differently (larger tick for higher res, or color-graded etc). Also, in the sidebar, the date of A|B should be diplayed (or currently it is as overlaid chips)
• light direction XYPad free mode (rather than datetime) displays underneath it ≈ 2026-04-05 · 08:45 local · closest match, IT SHOULD NOT please fix
• interstitial: fullscreen overlay shown between app entry and actual content, forcing a choice before proceeding. When it's specifically presenting options as cards to pick a mode/workspace/sub-app, people also call it: Selector modal / picker modal, entry point chooser, mode selector / context switcher, Launcher screen. In shadcn terms, it's typically built with Dialog (or Sheet) as the fullscreen overlay wrapper, with Card components inside for each option — sometimes paired with Command if there's also search/filtering. There's no single official spec name for it (unlike, say, "onboarding carousel"), so you'll see it called an interstitial, a chooser, or just "entry modal" depending on the design system's docs.
• Port over from historical: current split mode is actually historical side-by-side, it could be good to add a split mode, which does css clip-path crop, with same viewport in canvases, one clipped. Could do transparency or other css mix-blend blending mode properties (like difference, addition, etc). Bonus: the drag pill horiz position for size-percent, and vertical pos for opacity/transparency. See clipPath implementation here: https://github.com/Iconem/historical-satellite/blob/main/src/App.tsx
• other grid modes: modes other than 2x1 to compare more than 2 maps like 2x2, 3x1, eventually 3x2 or 4x1 Grid modes other than 2x1 like bbbike/mc 3x1, 2x2, 1x1 etc historical-satellite#63 and timeline labels would read a mapA...mapF in pill (A-F), and only display in case 2x1 the bottom left/right the dates labels.
• Would also be great to port export-multi, one set of historical imagery basemaps per feature from a drawing layer.
• note for later: a nice interaction for loads of timeline pills, would be handling maintaining Ctrl key while clicking a pill, then moving left, would also move all pills to the left of the selected one by the same amount (1, 2, 10 marks to the left). Same for moving to the right. The start of the drag would indicate which pills get dragged (only those on the side of the initial intention of drag), then how much to the left or right is given by where the cursor lands (on the one pill to the right, or 2, or 10 etc).
• add quick mention in changelog to grid mode being inspired by RealityScan, bbbike map compare.
• migrate from shiki large footprint to sugar-high with its react components, also if editable, or tanstack highlight see repo and blog post
• Histogram Equalization for basemap sources: Histogram matching / Equalization or Contrast Stretch historical-satellite#32
• expose changelog to user, probably a summarized succinct in general settings section, dumped from changelog.md in vite build copied but shorter? Could conventional commit and semver help? Can we find the largest commits backwards and add to changelog? Exposing what's new to users since last visit would also be great, notification pointing to changelog, changelog since last loaded app like revanced rvx. Part of the solution probably is tegami by fumanama. Give me the list of what's usually done for this, knowing I want to stay client side only to local storage notifications version last opened vs eg novu server notification. Tell me about my options.
• Clicking the "historical imagery" label (right of the 4x2 or grid mode A-H button) could set ALL map views to historical to avoid having to click on A-H
• Eventually point both domains, https://terrain-viewer.iconem.com/ and https://historical-satellite.iconem.com/ to the github hosted static site, and set ?appMode=historical if right route. Might be needed to keep old historical-sat, at old.historical?

Bookmarks, docs, coachmark changelog

• pre-populate bookmarks with some interesting visualization on some areas, mountains, city, various sources, nice screens thumbnails. probably-wont-do a Mode I'm feeling lucky or simple mode, choose one good combination of modes that looks nice, with eventually associated colorramp, and eventually viewport, and let the viewer evaluate that mode on various locations.
• changelog: add screenshots and gif for important updates like xypad, timeline, N grid, slope, SVF, etc. Make sure screens can open in gallery modal because would otherwise appear too small. Also add links to all sources added, terrain, basemap and historical. Also put link to scaffolding Ge_historicql_imagery link and repo.
• Docs/Landing page: More important, it's probable a fumadocs or fumapress would start to make sense to document features, with loads of screenshots or gifs, in addition to the settings changelog. VitePress or astro+starlight for a SSR github-page served would probably be simpler and make more sense. Eventually useful to reuse react components for landing like aceternity
• App Tours, Walkthroughs & Coach Marks, guided tours, via https://sglza.xyz/coachmark (or react joyride, reactors or shadcn tours)
• Coachmark: our own scrollTo could be ainmated with quick duration rather than jump, and scroll to just a few like 100px below, right now the section title or highlighted element ends up under the white to alpha gradient that indicates the meta section is scrollable.
• fix cam sync, map padding, center offset by elebation once dem tiles loaded etc