diff --git a/tools/pack.bash b/tools/pack.bash
index 1598de2..15ae3d1 100755
--- a/tools/pack.bash
+++ b/tools/pack.bash
@@ -3,4 +3,5 @@
 # Note: due to how Godot finds paths, this works best if cwd is this directory
 
 
-./pack_res.gd ++ $@
+BASENAMES=$(find -name 'VA_*.mdd' | sed s@\./@@ | sed s@\.mdd@@ | tr "\n" " ")
+./pack_res.gd ++ $BASENAMES
diff --git a/tools/pack_res.gd b/tools/pack_res.gd
index 258707b..5aedb12 100755
--- a/tools/pack_res.gd
+++ b/tools/pack_res.gd
@@ -17,6 +17,7 @@ var VertexAnimations = preload("VertexAnimations.gd")
 
 func _init():
 	var basenames := OS.get_cmdline_user_args()
+	print(basenames)
 
 	var animations = VertexAnimations.new()
 	animations.name = "VertexAnimations"
diff --git a/tools/src/main.rs b/tools/src/main.rs
index a922f7c..cad6983 100644
--- a/tools/src/main.rs
+++ b/tools/src/main.rs
@@ -122,15 +122,17 @@ fn _write_animation_info(filename: &str, info: AnimationInfo) -> Result<(), Box<
 enum PointState {
     Unseen,
     OneValue { point_idx: usize, point: Point },
-    Varying { new_idx: usize },
+    Varying,
+    Reindexed { new_idx: usize },
 }
 use PointState::*;
 impl PointState {
     fn mask_value(&self) -> f32 {
         match *self {
             Unseen => panic!("no point should be unseen"),
+            Varying => panic!("no point should be unindexed"),
             OneValue { .. } => -1.0,
-            Varying { new_idx, .. } => new_idx as f32,
+            Reindexed { new_idx, .. } => new_idx as f32,
         }
     }
     fn point_changed(a: &Point, b: &Point) -> bool {
@@ -138,7 +140,6 @@ impl PointState {
     }
 }
 
-
 fn main() {
     let basename = std::env::args()
         .nth(1)
@@ -152,7 +153,6 @@ fn main() {
 
     let mut mask_last: Vec<PointState> = vec![Unseen; info.total_points];
     let pc = MDDSeekableFile::read_frames(mdd_file.try_clone().unwrap()).unwrap();
-    let mut total_varying = 0;
     for frame in pc {
         let MDDFrame {
             point, point_idx, ..
@@ -165,13 +165,34 @@ fn main() {
             } => {
                 assert_eq!(old_point_idx, point_idx);
                 if PointState::point_changed(&point, &old_point) {
-                    mask_last[point_idx] = Varying {
-                        new_idx: total_varying,
-                    };
-                    total_varying += 1;
+                    mask_last[point_idx] = Varying;
                 }
             }
-            Varying { .. } => {}
+            Varying => {}
+            Reindexed { .. } => unreachable!()
+        }
+    }
+
+    let mut total_varying = 0;
+    for point in mask_last.iter_mut() {
+        if let Varying = point {
+            *point = Reindexed { new_idx: total_varying };
+            total_varying += 1;
+        }
+    }    
+
+    // Check that the varing indices are increasing w.r.t. point_idx
+    let mut mask_iter = mask_last.iter().filter_map(|x| {
+        if let &Reindexed { new_idx } = x {
+            Some(new_idx)
+        } else {
+            None
+        }
+    });
+    if let Some(mut prev_idx) = mask_iter.next() {
+        for next_idx in mask_iter {
+            assert_eq!(prev_idx + 1, next_idx);
+            prev_idx = next_idx;
         }
     }
 
@@ -199,9 +220,9 @@ fn main() {
             point_idx, point, ..
         } = frame.unwrap();
         match mask_last[point_idx] {
-            Unseen => panic!(),
+            Varying | Unseen => panic!(),
             OneValue { .. } => None,
-            Varying { .. } => Some(point),
+            Reindexed { .. } => Some(point),
         }
     }));