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@@ -167,6 +167,22 @@ If you don't need the tiles in separate files, you can use the SQLite output
 mode. For the same data as above, the SQLite database would be 73 MiB in size.
 ====
 
+=== DIFFERENT OVERLAYS
+
+By default, `hittekaart` generates a heatmap. However, it does also support
+different modes:
+
+tilehunter::
+    In this mode, a tile that is touched by at least one input track is marked
+    as green. The goal is to get as big of a filled square as possible. The
+    difference to *marktile* (see below) is that the markings operate on a
+    fixed zoom level.
+
+marktile::
+    In this mode, tiles that contain points are marked. The difference to
+    *tilehunter* is that the marking doesn't scale and always operates on the
+    map zoom level.
+
 == OPTIONS
 
 The following options are supported:
@@ -193,6 +209,14 @@ The following options are supported:
     separate PNG file. In this case, `-o` can be used to set the location of
     the SQLite database. The schema is described above.
 
+`-m MODE`, `--mode=MODE`::
+    Sets the overlay generation mode (heatmap, marktile, tilehunter). See
+    section DIFFERENT OVERLAYS for more information.
+
+`--tilehunter-zoom=ZOOM`::
+    Only effective in the tilehunter mode. Sets the zoom level at which the
+    tiles are marked.
+
 == EXAMPLE
 
 You can generate a heatmap and serve it locally with the following commands: