Clean up the outline view (#19)

Clean up the source code and interface of the outline view. In addition, [fix a bug](commit/6e42681b719d7ec97c4225ca321225979bf87b56) that could cause `Assembly::realize` to react to itself under certain circumstances. Those circumstances arose, making the bug noticeable, while this branch was being written.

#### Source code

- Modularize the `Outline` component into smaller components.
- Switch from static iteration to dynamic Sycamore lists. This reduces the amount of re-rendering that happens when an element or constraint changes. It also allows constraint details to stay open or closed during constraint updates, rather than resetting to closed.
- Make `Element::index` private, as discussed [here](pulls/15#issuecomment-1816).

#### Interface

- Make constraints editable, updating the assembly realization on input. Flag constraints where the Lorentz product value doesn't parse.
- Round element vector coordinates to prevent the displayed strings from overlapping.

Note that issue #20 was created by this PR, but it will be addressed shortly.

Co-authored-by: Aaron Fenyes <aaron.fenyes@fareycircles.ooo>
Reviewed-on: glen/dyna3#19
Co-authored-by: Vectornaut <vectornaut@nobody@nowhere.net>
Co-committed-by: Vectornaut <vectornaut@nobody@nowhere.net>

app-proto/src/assembly.rs

@@ -18,17 +18,33 @@ pub struct Element {
     pub id: String,
     pub label: String,
     pub color: ElementColor,
-    pub representation: DVector<f64>,
-    pub constraints: BTreeSet<ConstraintKey>,
+    pub representation: Signal<DVector<f64>>,
+    pub constraints: Signal<BTreeSet<ConstraintKey>>,
     
     // the configuration matrix column index that was assigned to this element
     // last time the assembly was realized
-    /* TO DO */
-    // this is public, as a kludge, because `Element` doesn't have a constructor
-    // yet. it should be made private as soon as the constructor is written
-    pub index: usize
+    column_index: usize
 }
 
+impl Element {
+    pub fn new(
+        id: String,
+        label: String,
+        color: ElementColor,
+        representation: DVector<f64>
+    ) -> Element {
+        Element {
+            id: id,
+            label: label,
+            color: color,
+            representation: create_signal(representation),
+            constraints: create_signal(BTreeSet::default()),
+            column_index: 0
+        }
+    }
+}
+            
+
 #[derive(Clone)]
 pub struct Constraint {
     pub subjects: (ElementKey, ElementKey),
@@ -92,24 +108,23 @@ impl Assembly {
         
         // create and insert a new element
         self.insert_element_unchecked(
-            Element {
-                id: id,
-                label: format!("Sphere {}", id_num),
-                color: [0.75_f32, 0.75_f32, 0.75_f32],
-                representation: DVector::<f64>::from_column_slice(&[0.0, 0.0, 0.0, 0.5, -0.5]),
-                constraints: BTreeSet::default(),
-                index: 0
-            }
+            Element::new(
+                id,
+                format!("Sphere {}", id_num),
+                [0.75_f32, 0.75_f32, 0.75_f32],
+                DVector::<f64>::from_column_slice(&[0.0, 0.0, 0.0, 0.5, -0.5])
+            )
         );
     }
     
     pub fn insert_constraint(&self, constraint: Constraint) {
         let subjects = constraint.subjects;
         let key = self.constraints.update(|csts| csts.insert(constraint));
-        self.elements.update(|elts| {
-            elts[subjects.0].constraints.insert(key);
-            elts[subjects.1].constraints.insert(key);
-        });
+        let subject_constraints = self.elements.with(
+            |elts| (elts[subjects.0].constraints, elts[subjects.1].constraints)
+        );
+        subject_constraints.0.update(|csts| csts.insert(key));
+        subject_constraints.1.update(|csts| csts.insert(key));
     }
     
     // --- realization ---
@@ -118,7 +133,7 @@ impl Assembly {
         // index the elements
         self.elements.update_silent(|elts| {
             for (index, (_, elt)) in elts.into_iter().enumerate() {
-                elt.index = index;
+                elt.column_index = index;
             }
         });
         
@@ -130,8 +145,8 @@ impl Assembly {
                 for (_, cst) in csts {
                     if cst.active.get_untracked() && cst.lorentz_prod_valid.get_untracked() {
                         let subjects = cst.subjects;
-                        let row = elts[subjects.0].index;
-                        let col = elts[subjects.1].index;
+                        let row = elts[subjects.0].column_index;
+                        let col = elts[subjects.1].column_index;
                         gram_to_be.push_sym(row, col, cst.lorentz_prod.get_untracked());
                     }
                 }
@@ -141,9 +156,9 @@ impl Assembly {
             // Gram matrix
             let mut guess_to_be = DMatrix::<f64>::zeros(5, elts.len());
             for (_, elt) in elts {
-                let index = elt.index;
+                let index = elt.column_index;
                 gram_to_be.push_sym(index, index, 1.0);
-                guess_to_be.set_column(index, &elt.representation);
+                guess_to_be.set_column(index, &elt.representation.get_clone_untracked());
             }
             
             (gram_to_be, guess_to_be)
@@ -185,11 +200,11 @@ impl Assembly {
         
         if success {
             // read out the solution
-            self.elements.update(|elts| {
-                for (_, elt) in elts.iter_mut() {
-                    elt.representation.set_column(0, &config.column(elt.index));
-                }
-            });
+            for (_, elt) in self.elements.get_clone_untracked() {
+                elt.representation.update(
+                    |rep| rep.set_column(0, &config.column(elt.column_index))
+                );
+            }
         }
     }
 }