.

2 files changed, 6 insertions, 3 deletions

diff --git a/src/wall-atlas.cpp b/src/wall-atlas.cpp
index 9b711f60..685125cd 100644
--- a/src/wall-atlas.cpp
+++ b/src/wall-atlas.cpp
@@ -47,7 +47,8 @@ StringView wall_atlas::name() const { return _info.name; }
 
 ArrayView<const wall_frame> wall_frames::items(const wall_atlas& a) const
 {
-    fm_debug_assert(index != (uint32_t)-1);
+    fm_assert(index < a.array().size());
+    fm_debug_assert(count != (uint32_t)-1);
     return { a.array() + index, count };
 }
 
diff --git a/src/wall-atlas.hpp b/src/wall-atlas.hpp
index 02d0ce91..4706a47b 100644
--- a/src/wall-atlas.hpp
+++ b/src/wall-atlas.hpp
@@ -18,13 +18,15 @@ struct wall_frame
 
 struct wall_frames
 {
-    uint32_t index = (uint32_t)-1, count = (uint32_t)-1;
+    ArrayView<const wall_frame> items(const wall_atlas& a) const;
+
+    uint32_t index = (uint32_t)-1, count = (uint32_t)-1; // not serialized
+
     Vector2ui pixel_size;
     Color4 tint_mult{1,1,1,1};
     Color3 tint_add;
     uint8_t from_rotation = (uint8_t)-1;
     bool mirrored : 1 = false;
-    ArrayView<const wall_frame> items(const wall_atlas& a) const;
 };
 
 struct wall_frame_set