Support drawing options in scheme.

It is now necessary to enable drawing map features in the scheme file.
In the `options` field one should enable the following features in
order to have these features on the map, because they are disabled by
default:
  - `draw_nodes`,
  - `draw_buildings`,
  - `draw_trees`,
  - `draw_craters`,
  - `draw_directions`

Related to #140.

map_machine/mapper.py

@@ -87,18 +87,26 @@ class Map:
                 path.update(figure.line_style.style)
                 self.svg.add(path)
 
+        if self.scheme.draw_trees:
             for tree in constructor.trees:
                 tree.draw(self.svg, self.flinger, self.scheme)
+
+        if self.scheme.draw_craters:
             for crater in constructor.craters:
                 crater.draw(self.svg, self.flinger)
 
-        self.draw_buildings(constructor, self.configuration.use_building_colors)
+        if self.scheme.draw_buildings:
+            self.draw_buildings(
+                constructor, self.configuration.use_building_colors
+            )
 
+        if self.scheme.draw_directions:
             for direction_sector in constructor.direction_sectors:
                 direction_sector.draw(self.svg, self.scheme)
 
         # All other points
 
+        if self.scheme.draw_nodes:
             occupied: Optional[Occupied]
             if self.configuration.overlap == 0:
                 occupied = None

map_machine/scheme.py

@@ -321,6 +321,16 @@ class Scheme:
                 for element in group["tags"]:
                     self.node_matchers.append(NodeMatcher(element, group))
 
+        options = content.get("options", {})
+
+        self.draw_nodes: bool = options.get("draw_nodes", False)
+
+        # Map features.
+        self.draw_buildings: bool = options.get("draw_buildings", False)
+        self.draw_trees: bool = options.get("draw_trees", False)
+        self.draw_craters: bool = options.get("draw_craters", False)
+        self.draw_directions: bool = options.get("draw_directions", False)
+
         self.colors: dict[str, str] = content.get("colors", {})
         self.material_colors: dict[str, str] = content.get(
             "material_colors", {}

map_machine/scheme/default.yml

@@ -1,3 +1,11 @@
+options:
+
+  draw_nodes: yes
+  draw_trees: yes
+  draw_craters: yes
+  draw_buildings: yes
+  draw_directions: yes
+
 colors:
 
   # Entity