Open large designs faster: meshes, face names and Measure on all cores (#916)

Display meshes after opening, the face names read when a feature finds a face by name, and inspect.measure over all bodies are now worked out per body on plain scoped threads (solidcraft_kernel::for_each_on_threads / map_on_threads), in body order and with the same results; the browser build stays serial.

crates/doc/src/eval.rs

@@ -619,6 +619,17 @@ impl ModelState {
     pub fn body(&self, name: &str) -> Option<&ModelBody> {
         self.bodies.iter().find(|b| b.name == name)
     }
+
+    /// Make every body's display mesh now, on all cores (bodies are meshed independently and
+    /// each keeps its own mesh, so the meshes are those `ModelBody::mesh` makes one by one).
+    /// Stops starting bodies once `go_on` says no.
+    pub fn warm_meshes(&self, go_on: impl Fn() -> bool + Sync) {
+        kernel::for_each_on_threads(&self.bodies, 16, |b| {
+            if go_on() {
+                let _ = b.mesh();
+            }
+        });
+    }
     pub fn sketch(&self, feature: u64) -> Option<&SolvedSketch> {
         self.sketches.iter().find(|s| s.feature == feature).map(|s| &**s)
     }

crates/doc/src/name_lookup.rs

@@ -260,6 +260,14 @@ impl EdgeHit {
 /// answering to it (merged into it, or the named piece told apart by the faces around it); else
 /// the piece of it nearest `p` (`split`).
 pub fn locate_face(st: &ModelState, name: &str, p: Vec3) -> Option<FaceHit> {
+    // Every body's names are read below: work out the ones not known yet on all cores first
+    // (each body's names are its own, whichever thread works them out).
+    if legacy_name(name).is_none() {
+        let bodies: Vec<&ModelBody> = st.bodies.iter().filter(|b| !b.body.is_mesh()).collect();
+        solidcraft_kernel::for_each_on_threads(&bodies, 16, |b| {
+            let _ = naming::names(b);
+        });
+    }
     locate_in(st.bodies.iter().enumerate().filter(|(_, b)| !b.body.is_mesh()), name, p)
 }