feat: save body and occurrence visibility with the design (#531) (#592)

Hidden bodies, occurrence placements, sketches and origin items are saved with the design and come back when it is reopened. Visibility is still not an undo step, but hiding or showing something now counts as an unsaved change. Additive field under format 16. Fixes #531.

Co-authored-by: jonaswre <jonas.wrede@beyondit.gmbh>

crates/engine/src/lib.rs

@@ -27,6 +27,7 @@ use solidcraft_geom::Vec3;
 
 pub use cmd::{CommandInfo, CommandSpec, auto_operation, command_specs, find_command};
 pub use solidcraft_doc as doc;
+pub use solidcraft_doc::Visibility;
 pub use solidcraft_geom as geom;
 pub use solidcraft_io as io;
 pub use solidcraft_kernel as kernel;
@@ -217,8 +218,11 @@ pub struct Session {
     pub section: Option<(Vec3, Vec3)>,
     /// Surface analysis shading the model (zebra, draft, curvature map).
     pub analysis: Option<SurfaceAnalysis>,
-    /// What is hidden or shown in the view (`browser.visibility`).
+    /// What is hidden or shown in the view (`browser.visibility`): saved with the design, not an
+    /// undo step. A design brings its saved visibility when it opens (`Session::new`).
     pub visibility: Visibility,
+    /// The visibility the design file holds (what `is_dirty` compares with).
+    saved_visibility: Visibility,
     /// States to go back to (`edit.checkpoint`, `edit.restore_checkpoint`): how batches of
     /// commands are undone however long the undo history is.
     pub(crate) checkpoints: Vec<Checkpoint>,
@@ -252,22 +256,6 @@ pub(crate) struct Checkpoint {
     pub redo: Vec<Snapshot>,
 }
 
-/// Items hidden or shown one by one (view state, not part of the design and not an undo step).
-#[derive(Clone, Debug, Default, PartialEq, serde::Serialize, serde::Deserialize)]
-#[serde(default)]
-pub struct Visibility {
-    /// Bodies by name.
-    pub hidden_bodies: Vec<String>,
-    /// Exact occurrence placements hidden with all descendants.
-    pub hidden_occurrences: Vec<Vec<u64>>,
-    /// Origin items (O, X, Y, Z, XY, XZ, YZ) and construction geometry, by name.
-    pub hidden_origin: Vec<String>,
-    /// Sketches by feature id.
-    pub hidden_sketches: Vec<u64>,
-    /// Finished sketches shown although a feature uses them.
-    pub shown_sketches: Vec<u64>,
-}
-
 /// A way of shading the model's faces to judge their shape (view state, not part of the design).
 #[derive(Clone, Copy, Debug, PartialEq, serde::Serialize, serde::Deserialize)]
 #[serde(tag = "type", rename_all = "snake_case")]
@@ -297,7 +285,9 @@ impl Default for Session {
 }
 
 impl Session {
-    pub fn new(doc: Document) -> Self {
+    pub fn new(mut doc: Document) -> Self {
+        // The session keeps what is hidden (not an undo step); the design file carries it.
+        let visibility = std::mem::take(&mut doc.visibility);
         let doc = Arc::new(doc);
         let mut model = Model::new();
         model.evaluate(&doc);
@@ -324,18 +314,31 @@ impl Session {
             analysis: None,
             checkpoints: Vec::new(),
             next_checkpoint: 1,
-            visibility: Visibility::default(),
+            saved_visibility: visibility.clone(),
+            visibility,
             #[cfg(test)]
             evaluations: 0,
             crash_journal: false,
         }
     }
 
+    /// The design has changes not in its file: in the document, or in what is hidden.
     pub fn is_dirty(&self) -> bool {
-        !Arc::ptr_eq(&self.doc, &self.saved) && *self.doc != *self.saved
+        (!Arc::ptr_eq(&self.doc, &self.saved) && *self.doc != *self.saved) || self.visibility != self.saved_visibility
     }
     pub fn mark_saved(&mut self) {
         self.saved = self.doc.clone();
+        self.saved_visibility = self.visibility.clone();
+    }
+
+    /// The design as a file holds it: the document with what is hidden in it.
+    pub fn design(&self) -> std::borrow::Cow<'_, Document> {
+        if self.visibility.is_empty() {
+            return std::borrow::Cow::Borrowed(&*self.doc);
+        }
+        let mut doc = (*self.doc).clone();
+        doc.visibility = self.visibility.clone();
+        std::borrow::Cow::Owned(doc)
     }
     /// The design has changes not in its file (a recovered design).
     pub fn mark_unsaved(&mut self) {
@@ -667,6 +670,7 @@ impl Session {
             checkpoints: Vec::new(),
             next_checkpoint: 1,
             visibility: self.visibility.clone(),
+            saved_visibility: self.saved_visibility.clone(),
             #[cfg(test)]
             evaluations: 0,
             crash_journal: false,