Board layers

kiln-core/src/object_def.rs

@@ -1,7 +1,7 @@
-use color::Rgba8;
-use std::collections::HashSet;
 use crate::glyph::Glyph;
 use crate::utils::ObjectId;
+use color::Rgba8;
+use std::collections::HashSet;
 
 /// A scripted object placed on the board, loaded from a map file.
 ///
@@ -32,6 +32,10 @@ pub struct ObjectDef {
     pub x: usize,
     /// Row of this object on the board (0-indexed).
     pub y: usize,
+    /// Index of the layer this object belongs to (0 = bottom). Determines its
+    /// draw order: objects on higher layers render above lower-layer terrain and
+    /// objects. Set at load from the layer the object's palette char appeared in.
+    pub z: usize,
     /// Visual representation of this object. Owned by the object (not derived
     /// from the grid cell), so scripts can change tile, fg, and bg at runtime.
     pub glyph: Glyph,
@@ -78,6 +82,7 @@ impl ObjectDef {
             id: 0,
             x,
             y,
+            z: 0,
             glyph: Self::default_glyph(),
             solid: true,
             opaque: true,
@@ -87,4 +92,4 @@ impl ObjectDef {
             name: None,
         }
     }
-}
+}