Liquify: saved projects show Distortion Mesh Offset too (#1194)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/effects/src/migrate.rs

@@ -239,6 +239,8 @@ fn refresh(pr: &mut Property, ps: &ParamSpec, spec: &EffectSpec) {
         // A path typed as text, or set only by commands, that got a Choose… button (Apply Color
         // LUT's LUT, the OCIO files, #514).
         (ParamUi::Hidden | ParamUi::Text, ParamUi::File { .. }) => pr.ui = ps.ui.clone(),
+        // An internal point that became a control (Liquify's Distortion Mesh Offset, #1194).
+        (ParamUi::Hidden, ParamUi::Point) => pr.ui = ParamUi::Point,
         // Same kind of value: take the spec's hints (units, ranges).
         (a, b) if std::mem::discriminant(a) == std::mem::discriminant(b) || is_numeric_ui(a) && is_numeric_ui(b) => pr.ui = ps.ui.clone(),
         _ => {}
@@ -514,6 +516,19 @@ mod tests {
         }
     }
 
+    /// #1194: Liquify's Distortion Mesh Offset was hidden; old projects show it, keeping its value.
+    #[test]
+    fn a_hidden_point_that_became_a_control_is_shown() {
+        let mut next = 1;
+        let (spec, mut g) = instance("ec.distort.liquify", &mut next);
+        let pr = g.get_mut("distortionMeshOffset").unwrap();
+        pr.ui = ParamUi::Hidden;
+        pr.value = Value::Vec2([20.0, -5.0]);
+        assert!(upgrade_instance(spec, &mut g, &mut Ids(&mut next), [100.0, 100.0]));
+        let pr = g.get("distortionMeshOffset").unwrap();
+        assert_eq!((&pr.ui, &pr.value), (&ParamUi::Point, &Value::Vec2([20.0, -5.0])));
+    }
+
     #[test]
     fn upgrade_moves_params_into_twirl_down_groups() {
         let spec = find(crate::warp_stab::ID).unwrap();