Add add_h3t_source() for tiled H3J (h3t) data

NAMESPACE

@@ -18,6 +18,7 @@ export(add_geolocate_control)
 export(add_globe_control)
 export(add_globe_minimap)
 export(add_h3j_source)
+export(add_h3t_source)
 export(add_heatmap_layer)
 export(add_image)
 export(add_image_source)

R/h3j-h3t.R

@@ -47,3 +47,84 @@ add_h3j_source <- function(map, id, url) {
 }
 
 
+# addH3TSource
+#' Add a tiled hexagon source from the H3 geospatial indexing system.
+#'
+#' Wraps the [h3t](https://github.com/INSPIDE/h3j-h3t) tile protocol, which
+#' registers a `h3tiles://` MapLibre protocol and fetches H3J-formatted JSON
+#' tiles from a `{z}/{x}/{y}` endpoint. Unlike [add_h3j_source()], which pulls
+#' a single H3J file, this source lets the map request only the cells visible
+#' in the current viewport — on pan/zoom the protocol handler fires a fresh
+#' request per tile.
+#'
+#' @param map A map object created by `maplibre()` or a `maplibre_proxy`.
+#' @param id Unique source ID.
+#' @param tiles A character vector of tile URL templates, each using the
+#'   `h3tiles://` scheme. The tokens `{z}`, `{x}`, `{y}` are substituted by
+#'   MapLibre on each tile request. Example:
+#'   `"h3tiles://h3t.example.com/{z}/{x}/{y}.h3t?q=..."`.
+#' @param sourcelayer Name of the source layer that downstream `add_fill_layer()`
+#'   (or similar) calls reference via `source_layer`. Defaults to `id`.
+#' @param geometry_type Either `"Polygon"` (hex boundaries) or `"Point"` (cell
+#'   centroids). Defaults to `"Polygon"`.
+#' @param minzoom,maxzoom Zoom bounds for the source (MapLibre semantics).
+#' @param promote_id Whether to promote the `h3id` property to the feature ID.
+#' @param debug If `TRUE`, the protocol handler logs per-tile timing to the
+#'   browser console.
+#' @references https://github.com/INSPIDE/h3j-h3t
+#' @export
+#' @examplesIf interactive()
+#' maplibre(center = c(-119, 34), zoom = 5) |>
+#'   add_h3t_source(
+#'     id = "sardine",
+#'     tiles = "h3tiles://h3t.example.com/{z}/{x}/{y}.h3t?q=<base64-SELECT>"
+#'   ) |>
+#'   add_fill_layer(
+#'     id           = "sardine",
+#'     source       = "sardine",
+#'     source_layer = "sardine",
+#'     fill_color   = interpolate(
+#'       column = "value", values = c(0, 100),
+#'       stops = c("#ffffcc", "#e31a1c")
+#'     ),
+#'     fill_opacity = 0.7
+#'   )
+add_h3t_source <- function(map, id, tiles,
+                           sourcelayer    = id,
+                           geometry_type  = c("Polygon", "Point"),
+                           minzoom        = 0,
+                           maxzoom        = 14,
+                           promote_id     = TRUE,
+                           debug          = FALSE) {
+  geometry_type <- match.arg(geometry_type)
+  if (is.character(tiles)) tiles <- as.list(tiles)
+  stopifnot(is.list(tiles), length(tiles) >= 1L)
+
+  h3t_source <- list(
+    id            = id,
+    tiles         = tiles,
+    sourcelayer   = sourcelayer,
+    geometry_type = geometry_type,
+    minzoom       = minzoom,
+    maxzoom       = maxzoom,
+    promoteId     = promote_id,
+    debug         = debug
+  )
+
+  if (inherits(map, "mapboxgl_proxy") || inherits(map, "maplibre_proxy")) {
+    proxy_class <- if (inherits(map, "mapboxgl_proxy")) "mapboxgl-proxy" else "maplibre-proxy"
+    map$session$sendCustomMessage(
+      proxy_class,
+      list(
+        id      = map$id,
+        message = list(type = "add_h3t_sources", h3t_sources = list(h3t_source))
+      )
+    )
+  } else {
+    map$x$h3t_sources <- c(map$x$h3t_sources, list(h3t_source))
+  }
+
+  map
+}
+
+

inst/htmlwidgets/maplibregl.js

@@ -1309,6 +1309,22 @@ HTMLWidgets.widget({
               }
             });
           }
+          if (x.h3t_sources) {
+            x.h3t_sources.forEach(function (source) {
+              map.addH3TSource(source.id, {
+                tiles: source.tiles,
+                sourcelayer: source.sourcelayer,
+                geometry_type: source.geometry_type,
+                minzoom: source.minzoom,
+                maxzoom: source.maxzoom,
+                promoteId: source.promoteId,
+                debug: source.debug,
+              });
+              if (x.layers) {
+                x.layers.forEach((layer) => add_my_layers(layer));
+              }
+            });
+          }
 
           // Add layers if provided
           if (x.layers) {
@@ -2568,6 +2584,30 @@ if (HTMLWidgets.shinyMode) {
         map.setFilter(message.layer, message.filter);
         // Track filter state for layer restoration
         layerState.filters[message.layer] = message.filter;
+      } else if (message.type === "add_h3t_sources") {
+        (message.h3t_sources || []).forEach(function (source) {
+          try {
+            map.addH3TSource(source.id, {
+              tiles: source.tiles,
+              sourcelayer: source.sourcelayer,
+              geometry_type: source.geometry_type,
+              minzoom: source.minzoom,
+              maxzoom: source.maxzoom,
+              promoteId: source.promoteId,
+              debug: source.debug,
+            });
+          } catch (e) {
+            console.error("addH3TSource failed for", source.id, e);
+          }
+        });
+      } else if (message.type === "add_h3j_sources") {
+        (message.h3j_sources || []).forEach(async function (source) {
+          try {
+            await map.addH3JSource(source.id, { data: source.url });
+          } catch (e) {
+            console.error("addH3JSource failed for", source.id, e);
+          }
+        });
       } else if (message.type === "add_source") {
         if (message.source.type === "vector") {
           const sourceConfig = {

inst/htmlwidgets/maplibregl.yaml

@@ -46,7 +46,7 @@ dependencies:
     script:
       - "pmtiles.js"
   - name: h3j-h3t
-    version: 0.9.2
+    version: 0.9.7
     src: "htmlwidgets/lib/h3j-h3t"
     script:
       - "h3j_h3t.js"

inst/htmlwidgets/maplibregl_compare.js

@@ -1,3 +1,7 @@
+// build marker for bbest/mapgl feat/add-h3t-source — bump on every JS change
+window.__mapgl_h3t_build = "2026-04-22g";
+console.log("[mapgl] maplibregl_compare.js build:", window.__mapgl_h3t_build);
+
 function evaluateExpression(expression, properties) {
   if (!Array.isArray(expression)) {
     return expression;
@@ -3046,6 +3050,20 @@ HTMLWidgets.widget({
               });
             });
           }
+          // Process H3T (tiled h3j) sources if provided
+          if (mapData.h3t_sources) {
+            mapData.h3t_sources.forEach(function (source) {
+              map.addH3TSource(source.id, {
+                tiles: source.tiles,
+                sourcelayer: source.sourcelayer,
+                geometry_type: source.geometry_type,
+                minzoom: source.minzoom,
+                maxzoom: source.maxzoom,
+                promoteId: source.promoteId,
+                debug: source.debug,
+              });
+            });
+          }
 
           if (mapData.markers) {
             if (!window.maplibreglMarkers) {
@@ -4227,12 +4245,18 @@ HTMLWidgets.widget({
                 link.setAttribute("data-layer-ids", JSON.stringify(layerIds));
                 link.setAttribute("data-layer-type", config.type);
 
-                // Check if the first layer's visibility is set to "none" initially
+                // Check if the first layer's visibility is set to "none" initially.
+                // In a compare widget each side only has its own layers, but a single
+                // layers_control can reference ids from both sides (e.g. "sp" and "env")
+                // so the toggle can fire on both maps. If the first id isn't present on
+                // this map, fall back to "visible". We pre-check with getLayer() because
+                // getLayoutProperty() on a missing layer fires an error event (not a
+                // throw), which try/catch cannot silence.
                 const firstLayerId = layerIds[0];
-                const initialVisibility = map.getLayoutProperty(
-                  firstLayerId,
-                  "visibility",
-                );
+                let initialVisibility = "visible";
+                if (map.getLayer(firstLayerId)) {
+                  initialVisibility = map.getLayoutProperty(firstLayerId, "visibility") || "visible";
+                }
                 link.className = initialVisibility === "none" ? "" : "active";
 
                 // Show or hide layer(s) when the toggle is clicked
@@ -4244,17 +4268,22 @@ HTMLWidgets.widget({
                   const layerIds = JSON.parse(
                     this.getAttribute("data-layer-ids"),
                   );
+                  // read visibility from whichever map actually has this layer
+                  // (pre-check with getLayer() — getLayoutProperty fires an error
+                  // event on missing layers and try/catch cannot silence it)
                   const firstLayerId = layerIds[0];
-                  const visibility = map.getLayoutProperty(
-                    firstLayerId,
-                    "visibility",
-                  );
-
-                  const newVis = visibility === "visible" ? "none" : "visible";
+                  let visibility;
+                  for (const m of [map, beforeMap, afterMap]) {
+                    if (!m || !m.getLayer(firstLayerId)) continue;
+                    visibility = m.getLayoutProperty(firstLayerId, "visibility");
+                    if (visibility !== undefined) break;
+                  }
+                  const newVis = (visibility || "visible") === "visible" ? "none" : "visible";
                   const allMaps = [beforeMap, afterMap];
                   layerIds.forEach((layerId) => {
                     allMaps.forEach((m) => {
-                      try { m.setLayoutProperty(layerId, "visibility", newVis); } catch(err) {}
+                      if (!m || !m.getLayer(layerId)) return;
+                      m.setLayoutProperty(layerId, "visibility", newVis);
                     });
                   });
                   this.className = newVis === "visible" ? "active" : "";

inst/htmlwidgets/maplibregl_compare.yaml

@@ -53,7 +53,7 @@ dependencies:
     script:
       - "pmtiles.js"
   - name: h3j-h3t
-    version: 0.9.2
+    version: 0.9.7
     src: "htmlwidgets/lib/h3j-h3t"
     script:
       - "h3j_h3t.js"