Issue #10: support priority for icons.

roentgen/constructor.py

@@ -340,11 +340,15 @@ class Constructor:
             if (line.get_tag("area") == "yes" or
                     is_cycle(outers[0]) and line.get_tag("area") != "no" and
                     self.scheme.is_area(line.tags)):
-                icon_set: IconSet = self.scheme.get_icon(
+
+                priority: int
+                icon_set: IconSet
+                icon_set, priority = self.scheme.get_icon(
                     self.icon_extractor, line.tags, for_="line")
+
                 self.nodes.append(Point(
                     icon_set, line.tags, center_point, center_coordinates,
-                    is_for_node=False))
+                    is_for_node=False, priority=priority))
 
         if not line_styles:
             if DEBUG:
@@ -353,11 +357,15 @@ class Constructor:
                     "stroke-width": 1}
                 self.figures.append(Figure(
                     line.tags, inners, outers, LineStyle(style, 1000)))
-            icon_set: IconSet = self.scheme.get_icon(
+
+            priority: int
+            icon_set: IconSet
+            icon_set, priority = self.scheme.get_icon(
                 self.icon_extractor, line.tags)
+
             self.nodes.append(Point(
                 icon_set, line.tags, center_point, center_coordinates,
-                is_for_node=False))
+                is_for_node=False, priority=priority))
 
     def construct_relations(self) -> None:
         """
@@ -410,7 +418,9 @@ class Constructor:
             if not self.check_level(tags):
                 continue
 
-            icon_set: IconSet = self.scheme.get_icon(self.icon_extractor, tags)
+            priority: int
+            icon_set: IconSet
+            icon_set, priority = self.scheme.get_icon(self.icon_extractor, tags)
 
             if self.mode in ["time", "user-coloring"]:
                 if not tags:
@@ -421,7 +431,8 @@ class Constructor:
             if self.mode == "time":
                 icon_set.color = get_time_color(node.timestamp, self.map_.time)
 
-            self.nodes.append(Point(icon_set, tags, flung, node.coordinates))
+            self.nodes.append(Point(
+                icon_set, tags, flung, node.coordinates, priority=priority))
 
             missing_tags.update(
                 f"{key}: {tags[key]}" for key in tags

roentgen/mapper.py

@@ -230,7 +230,7 @@ class Painter:
             occupied = Occupied(
                 self.flinger.size[0], self.flinger.size[1], self.overlap)
 
-        nodes = sorted(constructor.nodes, key=lambda x: x.layer)
+        nodes = sorted(constructor.nodes, key=lambda x: -x.priority)
         for index, node in enumerate(nodes):  # type: int, Point
             if (node.get_tag("natural") == "tree" and
                     ("diameter_crown" in node.tags or

roentgen/scheme.py

@@ -8,7 +8,7 @@ import yaml
 
 from colour import Color
 from dataclasses import dataclass
-from typing import Any, Dict, List, Optional, Set, Union
+from typing import Any, Dict, List, Optional, Set, Union, Tuple
 
 from roentgen.icon import DEFAULT_SHAPE_ID, IconExtractor, Icon
 
@@ -104,7 +104,7 @@ class Scheme:
         self.prefix_to_skip: List[str] = content["prefix_to_skip"]
 
         # Storage for created icon sets.
-        self.cache: Dict[str, IconSet] = {}
+        self.cache: Dict[str, Tuple[IconSet, int]] = {}
 
     def get_color(self, color: str) -> Color:
         """
@@ -156,7 +156,7 @@ class Scheme:
 
     def get_icon(
             self, icon_extractor: IconExtractor, tags: Dict[str, Any],
-            for_: str = "node") -> IconSet:
+            for_: str = "node") -> Tuple[IconSet, int]:
         """
         Construct icon set.
 
@@ -172,11 +172,14 @@ class Scheme:
         extra_icon_ids: List[List[str]] = []
         processed: Set[str] = set()
         fill: Color = DEFAULT_COLOR
+        priority: int = 0
 
-        for matcher in self.icons:  # type: Dict[str, Any]
+        for index, matcher in enumerate(self.icons):
+            # type: (int, Dict[str, Any])
             matched: bool = is_matched(matcher, tags)
             if not matched:
                 continue
+            priority = len(self.icons) - index
             if "draw" in matcher and not matcher["draw"]:
                 processed |= set(matcher["tags"].keys())
             if "icon" in matcher:
@@ -229,9 +232,9 @@ class Scheme:
         returned: IconSet = IconSet(
             main_icon, extra_icons, fill, processed, is_default)
 
-        self.cache[tags_hash] = returned
+        self.cache[tags_hash] = returned, priority
 
-        return returned
+        return returned, priority
 
     def get_style(self, tags: Dict[str, Any], scale):