Increase hillshade source from 12 to 13.

It still avoids strong artifacts and maplibre-gl 4 is using much less
memory.

Reduce maximum hillshade-exaggeration from 1 to 0.5.
The default is 0.5; going higher throws away contrast.

src/js/style.js

@@ -21,7 +21,7 @@ export function build(tileURL, spriteURL, glyphURL, locales) {
         encoding: "terrarium",
         tileSize: 256,
         // The actual maxzoom is 15
-        maxzoom: 12,
+        maxzoom: 13,
       },
     },
     sprite: spriteURL,

src/layer/hillshade.js

@@ -2,20 +2,15 @@ export const hillshading = {
   id: "hillshading",
   type: "hillshade",
   source: "dem",
-  maxzoom: 17,
   paint: {
     "hillshade-exaggeration": [
       "interpolate",
       ["linear"],
       ["zoom"],
-      6,
-      1,
       12,
-      0.7,
-      16,
-      0.1,
+      0.5,
       17,
-      0,
+      0.1,
     ],
     "hillshade-shadow-color": "hsla(30, 14%, 76%, 1)",
     "hillshade-highlight-color": "hsla(30, 44%, 99%, 1)",