doc: add some docstring for assemblicon context

tool/src/aurora_iconset_builder/assemblicon/context.py

@@ -184,25 +184,51 @@ class AdvancedContext:
     def __intern_render_svg(
         self, src: Path, dst: Optional[Path], cfg: SvgConfig
     ) -> Path:
+        """
+        Internal used function for rendering SVG.
+
+        :return: The path to destination storing render result.
+        """
         if dst is None:
             dst = self.__allocate_lib_temporary_artifact(".png")
         artrender.render_svg(src, dst, self.__context.prerequisite.svg_render, cfg)
         return dst
 
     def render_svg(
-        self, src: Path, dst: Optional[Path], cfg: SvgConfig = _DEFAULT_SVG_CONFIG
+        self, src: Path, dst: Path, cfg: SvgConfig = _DEFAULT_SVG_CONFIG
     ) -> None:
+        """
+        Just render given SVG to PNG file.
+
+        :param src: The path to SVG file to be rendered.
+        :param dst: The path to rendered PNG file.
+        :param cfg: The configuration when rendering SVG file. Default for vanilla artifact.
+        """
         self.__intern_render_svg(src, dst, cfg)
 
     def render_svg_then_load(
         self, src: Path, dst: Optional[Path], cfg: SvgConfig = _DEFAULT_SVG_CONFIG
     ) -> Artifact:
+        """
+        Render given SVG to PNG file, then load it directly.
+
+        :param src: The path to SVG file to be rendered.
+        :param dst: The path to rendered PNG file.
+            ``None`` if you don't need to store it in temporary or output directory.
+        :param cfg: The configuration when rendering SVG file. Default for vanilla artifact.
+        :return: The loaded built PNG file.
+        """
         dst = self.__intern_render_svg(src, dst, cfg)
         return artio.load_artifact(dst)
 
     def __intern_render_blender(
         self, src: Path, dst: Optional[Path], cfg: BlenderConfig
     ) -> Path:
+        """
+        Internal used function for rendering Blender composition.
+
+        :return: The path to destination storing render result.
+        """
         temp_script = self.__fetch_const_lib_temporary_artifact("blender.py")
         if dst is None:
             dst = self.__allocate_lib_temporary_artifact(".png")
@@ -210,13 +236,29 @@ class AdvancedContext:
         return dst
 
     def render_blender(
-        self, src: Path, dst: Optional[Path], cfg: BlenderConfig = _DEFAULT_BLD_CONFIG
+        self, src: Path, dst: Path, cfg: BlenderConfig = _DEFAULT_BLD_CONFIG
     ) -> None:
+        """
+        Just render given Blender composition to PNG file.
+
+        :param src: The path to Blender composition file to be rendered.
+        :param dst: The path to rendered PNG file.
+        :param cfg: The configuration when rendering Blender composition file. Default for vanilla artifact.
+        """
         self.__intern_render_blender(src, dst, cfg)
 
     def render_blender_then_load(
         self, src: Path, dst: Optional[Path], cfg: BlenderConfig = _DEFAULT_BLD_CONFIG
     ) -> Artifact:
+        """
+        Render given Blender composition to PNG file, then load it directly.
+
+        :param src: The path to Blender composition file to be rendered.
+        :param dst: The path to rendered PNG file.
+            ``None`` if you don't need to store it in temporary or output directory.
+        :param cfg: The configuration when rendering Blender composition file. Default for vanilla artifact.
+        :return: The loaded built PNG file.
+        """
         dst = self.__intern_render_blender(src, dst, cfg)
         return artio.load_artifact(dst)