diff --git a/src/scene.rs b/src/scene.rs
index 86a78c3..a0dba0c 100644
--- a/src/scene.rs
+++ b/src/scene.rs
@@ -38,6 +38,9 @@ impl Scene {
     }
 }
 
+/// scene name is derived from the filename,
+/// and None values are represented as "" in the toml
+/// so it's Vec<String> instead of Vec<Option<String>>
 #[derive(Serialize, Deserialize)]
 struct IntermediateScene {
     background: Vec<String>,