add icons manager. show icons in group

bbp_ng/UTIL_icons_manager.py

@@ -1,7 +1,113 @@
-import bpy
-import os, enum
+import bpy, bpy.utils.previews
+import os, enum, typing
 
 class BlenderPresetIcons(enum.Enum):
     Info = 'INFO'
     Warning = 'ERROR'
     Error = 'CANCEL'
+
+#region Custom Icons Helper
+
+_g_SupportedImageExts: set[str] = (
+    '.png',
+)
+
+_g_IconsManager: bpy.utils.previews.ImagePreviewCollection | None = None
+
+_g_EmptyIcon: int = 0
+_g_IconPrefix: str = "BlcBldPlg_"
+
+_g_FloorIconsMap: dict[str, int] = {}
+_g_FloorIconPrefix: str = _g_IconPrefix + 'Floor_'
+_g_ElementIconsMap: dict[str, int] = {}
+_g_ElementIconPrefix: str = _g_IconPrefix + 'Element_'
+_g_GroupIconsMap: dict[str, int] = {}
+_g_GroupIconPrefix: str = _g_IconPrefix + 'Group_'
+
+def _iterate_folder_images(folder: str) -> typing.Iterator[tuple[str, str]]:
+    for name in os.listdir(folder):
+        # check whether it is file
+        filepath: str = os.path.join(folder, name)
+        if os.path.isfile(filepath):
+            # check file exts
+            (root, ext) = os.path.splitext(name)
+            if ext.lower() in _g_SupportedImageExts:
+                yield (filepath, root)
+
+def _load_image_folder(
+        folder: str, 
+        loader: bpy.utils.previews.ImagePreviewCollection, 
+        container: dict[str, int],
+        name_prefix: str) -> None:
+    # iterate folder
+    for (filepath, filename_no_ext) in _iterate_folder_images(folder):
+        # generate name for unique
+        icon_name: str = name_prefix + filename_no_ext
+        # load it
+        loader.load(icon_name, filepath, 'IMAGE')
+        # add into list. use plain name (not the unique name)
+        container[filename_no_ext] = loader[icon_name].icon_id
+
+#endregion
+
+#region Custom Icons Visitors
+
+def get_empty_icon() -> int:
+    return _g_EmptyIcon
+
+def get_floor_icon(name: str) -> int | None:
+    return _g_FloorIconsMap.get(name, None)
+
+def get_element_icon(name: str) -> int | None:
+    return _g_ElementIconsMap.get(name, None)
+
+def get_group_icon(name: str) -> int | None:
+    return _g_GroupIconsMap.get(name, None)
+
+#endregion
+
+def register():
+    global _g_IconsManager
+    global _g_EmptyIcon
+    global _g_FloorIconsMap, _g_ElementIconsMap, _g_GroupIconsMap
+
+    # create preview collection and get icon folder
+    icons_folder: str = os.path.join(os.path.dirname(__file__), "icons")
+    _g_IconsManager = bpy.utils.previews.new()
+
+    # load empty icon as default fallback
+    empty_icon_name: str = _g_IconPrefix + 'EmptyIcon'
+    _g_IconsManager.load(empty_icon_name, os.path.join(icons_folder, "Empty.png"), 'IMAGE')
+    _g_EmptyIcon = _g_IconsManager[empty_icon_name].icon_id
+
+    # load floor, element, group icon
+    _load_image_folder(
+        os.path.join(icons_folder, 'floor'),
+        _g_IconsManager,
+        _g_FloorIconsMap,
+        _g_FloorIconPrefix
+    )
+    _load_image_folder(
+        os.path.join(icons_folder, 'element'),
+        _g_IconsManager,
+        _g_ElementIconsMap,
+        _g_ElementIconPrefix
+    )
+    _load_image_folder(
+        os.path.join(icons_folder, 'group'),
+        _g_IconsManager,
+        _g_GroupIconsMap,
+        _g_GroupIconPrefix
+    )
+
+def unregister():
+    global _g_IconsManager
+    global _g_EmptyIcon
+    global _g_FloorIconsMap, _g_ElementIconsMap, _g_GroupIconsMap
+
+    bpy.utils.previews.remove(_g_IconsManager)
+    _g_IconsManager = None
+
+    _g_FloorIconsMap.clear()
+    _g_ElementIconsMap.clear()
+    _g_GroupIconsMap.clear()