Check tangent space sync when deforming

Only give elements column indices once they've actually been through a
realization. Ignore motions of elements that haven't been through a
realization. Get the dimensions of the projected motion matrix from the
saved tangent space, not the current number of elements.

app-proto/src/engine.rs

@@ -88,11 +88,17 @@ impl PartialMatrix {
 // --- configuration subspaces ---
 
 #[derive(Clone)]
-pub struct ConfigSubspace(Vec<DMatrix<f64>>);
+pub struct ConfigSubspace {
+    assembly_dim: usize,
+    basis: Vec<DMatrix<f64>>
+}
 
 impl ConfigSubspace {
-    pub fn zero() -> ConfigSubspace {
-        ConfigSubspace(Vec::new())
+    pub fn zero(assembly_dim: usize) -> ConfigSubspace {
+        ConfigSubspace {
+            assembly_dim: assembly_dim,
+            basis: Vec::new()
+        }
     }
     
     // approximate the kernel of a symmetric endomorphism of the configuration
@@ -119,12 +125,18 @@ impl ConfigSubspace {
             format!("Eigenvalues used to find kernel: {}", eig.eigenvalues)
         ));
         
-        ConfigSubspace(basis.collect())
+        ConfigSubspace {
+            assembly_dim: assembly_dim,
+            basis: basis.collect()
+        }
     }
     
     pub fn dim(&self) -> usize {
-        let ConfigSubspace(basis) = self;
-        basis.len()
+        self.basis.len()
+    }
+    
+    pub fn assembly_dim(&self) -> usize {
+        self.assembly_dim
     }
     
     // find the projection onto this subspace of the motion where the element
@@ -133,8 +145,7 @@ impl ConfigSubspace {
     // for the zero subspace, this method's behavior doesn't match its name: it
     // panics rather than returning zero
     pub fn proj(&self, v: &DVectorView<f64>, column_index: usize) -> DMatrix<f64> {
-        let ConfigSubspace(basis) = self;
-        basis.into_iter().map(
+        self.basis.iter().map(
             |b| b.column(column_index).dot(&v) * b
         ).sum()
     }
@@ -325,14 +336,14 @@ pub fn realize_gram(
                 state = better_state;
                 history.backoff_steps.push(backoff_steps);
             },
-            None => return (state.config, ConfigSubspace::zero(), false, history)
+            None => return (state.config, ConfigSubspace::zero(assembly_dim), false, history)
         };
     }
     let success = state.loss < tol;
     let tangent = if success {
         ConfigSubspace::symmetric_kernel(hess, assembly_dim)
     } else {
-        ConfigSubspace::zero()
+        ConfigSubspace::zero(assembly_dim)
     };
     (state.config, tangent, success, history)
 }