Enforce constraints in the editor

app-proto/src/assembly.rs

@@ -1,8 +1,11 @@
-use nalgebra::DVector;
+use nalgebra::{DMatrix, DVector};
 use rustc_hash::FxHashMap;
 use slab::Slab;
 use std::collections::BTreeSet;
 use sycamore::prelude::*;
+use web_sys::{console, wasm_bindgen::JsValue}; /* DEBUG */
+
+use crate::engine::{realize_gram, PartialMatrix};
 
 #[derive(Clone, PartialEq)]
 pub struct Element {
@@ -10,7 +13,10 @@ pub struct Element {
     pub label: String,
     pub color: [f32; 3],
     pub rep: DVector<f64>,
-    pub constraints: BTreeSet<usize>
+    pub constraints: BTreeSet<usize>,
+    
+    // internal properties, not reflected in any view
+    pub index: usize
 }
 
 #[derive(Clone)]
@@ -40,6 +46,8 @@ impl Assembly {
         }
     }
     
+    // --- inserting elements and constraints ---
+    
     // insert an element into the assembly without checking whether we already
     // have an element with the same identifier. any element that does have the
     // same identifier will get kicked out of the `elements_by_id` index
@@ -77,7 +85,8 @@ impl Assembly {
                 label: format!("Sphere {}", id_num),
                 color: [0.75_f32, 0.75_f32, 0.75_f32],
                 rep: DVector::<f64>::from_column_slice(&[0.0, 0.0, 0.0, 0.5, -0.5]),
-                constraints: BTreeSet::default()
+                constraints: BTreeSet::default(),
+                index: 0
             }
         );
     }
@@ -90,4 +99,83 @@ impl Assembly {
             elts[args.1].constraints.insert(key);
         })
     }
+    
+    // --- realization ---
+    
+    pub fn realize(&self) {
+        // index the elements
+        self.elements.update_silent(|elts| {
+            for (index, (_, elt)) in elts.into_iter().enumerate() {
+                elt.index = index;
+            }
+        });
+        
+        // set up the Gram matrix and the initial configuration matrix
+        let (gram, guess) = self.elements.with_untracked(|elts| {
+            // set up the off-diagonal part of the Gram matrix
+            let mut gram_to_be = PartialMatrix::new();
+            self.constraints.with_untracked(|csts| {
+                for (_, cst) in csts {
+                    let args = cst.args;
+                    let row = elts[args.0].index;
+                    let col = elts[args.1].index;
+                    gram_to_be.push_sym(row, col, cst.rep);
+                }
+            });
+            
+            // set up the initial configuration matrix and the diagonal of the
+            // Gram matrix
+            let mut guess_to_be = DMatrix::<f64>::zeros(5, elts.len());
+            for (_, elt) in elts {
+                let index = elt.index;
+                gram_to_be.push_sym(index, index, 1.0);
+                guess_to_be.set_column(index, &elt.rep);
+            }
+            
+            (gram_to_be, guess_to_be)
+        });
+        
+        /* DEBUG */
+        // log the Gram matrix
+        console::log_1(&JsValue::from("Gram matrix:"));
+        gram.log_to_console();
+        
+        /* DEBUG */
+        // log the initial configuration matrix
+        console::log_1(&JsValue::from("old configuration:"));
+        for j in 0..guess.nrows() {
+            let mut row_str = String::new();
+            for k in 0..guess.ncols() {
+                row_str.push_str(format!(" {:>8.3}", guess[(j, k)]).as_str());
+            }
+            console::log_1(&JsValue::from(row_str));
+        }
+        
+        // look for a configuration with the given Gram matrix
+        let (config, success, history) = realize_gram(
+            &gram, guess, &[],
+            1.0e-12, 0.5, 0.9, 1.1, 200, 110
+        );
+        
+        /* DEBUG */
+        // report the outcome of the search
+        console::log_1(&JsValue::from(
+            if success {
+                "Target accuracy achieved!"
+            } else {
+                "Failed to reach target accuracy"
+            }
+        ));
+        console::log_2(&JsValue::from("Steps:"), &JsValue::from(history.scaled_loss.len() - 1));
+        console::log_2(&JsValue::from("Loss:"), &JsValue::from(*history.scaled_loss.last().unwrap()));
+        
+        if success {
+            // read out the solution
+            self.elements.update(|elts| {
+                for (_, elt) in elts.iter_mut() {
+                    elt.rep.set_column(0, &config.column(elt.index));
+                }
+            });
+        }
+    }
 }