Fix/Unfix on every sketch entity: points (Fix constraint) and lines, arcs, circles, ellipses, splines and conics (fixed curves hold their points and radius); ConstraintFix takes entities (fixes them all unless all are fixed); the toolbar button and the context menu act on the whole selection; fixed points never move when dragged or solved; projected geometry counts as fixed; fixed geometry is drawn green; sketch.inspect reports fixed

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AS5Tn3xieewUSg3uxrMVdL

crates/ui-egui/src/context_menu.rs

@@ -586,11 +586,8 @@ pub fn run_item(app: &mut SolveApp, item: &Item, at: Pos2) {
         "ui.unsection" => drop(app.run("FusionHalfSectionViewCommand", json!({"clear": true}))),
         "ui.fit" => app.animate_view("fit"),
         "ui.home" => app.animate_view("home"),
-        "ui.fix" => {
-            for e in strs(&p, "entities") {
-                let _ = app.run("ConstraintFix", json!({ "entity": e }));
-            }
-        }
+        // One command for the whole selection: all fixed unless all already are.
+        "ui.fix" => drop(app.run("ConstraintFix", json!({ "entities": strs(&p, "entities") }))),
         "ui.editSketch" => {
             if let Some(id) = id_of(&p, "sketch") {
                 app.edit_sketch(id);

crates/ui-egui/src/lib.rs

@@ -295,6 +295,22 @@ impl SolveApp {
             let edges = self.session.selection.iter().any(|s| matches!(s, solvecraft_engine::Sel::Edge { .. }));
             return self.start(if edges { "FusionFilletEdgesCommand" } else { "Extrude" });
         }
+        // Fix/Unfix: the selected sketch points and curves change at once, otherwise pick them.
+        if id == "ConstraintFix" {
+            let ents: Vec<String> = self
+                .session
+                .selection
+                .iter()
+                .filter_map(|s| match s {
+                    solvecraft_engine::Sel::SketchCurve { id } | solvecraft_engine::Sel::SketchPoint { id } => Some(id.clone()),
+                    _ => None,
+                })
+                .collect();
+            if !ents.is_empty() {
+                let _ = self.run(id, json!({ "entities": ents }));
+                return;
+            }
+        }
         // Construction toggle: selected sketch curves switch at once, otherwise pick them.
         if id == "sketch.construction" {
             let curves: Vec<String> = self

crates/ui-egui/src/viewport.rs

@@ -178,6 +178,8 @@ fn sketch_color(t: &Tokens, c: Rgb) -> [u8; 4] {
         c4(t.sketch)
     } else if c == colors::SKETCH_DONE || c == colors::SKETCH_FIXED {
         c4(t.sketch_fixed)
+    } else if c == colors::SKETCH_LOCKED {
+        c4(t.sketch_locked)
     } else {
         rgba(c)
     }
@@ -1265,13 +1267,20 @@ fn overlays(app: &SolveApp, painter: &egui::Painter, proj: &Proj) {
     let Some(sid) = app.session.active_sketch else { return };
     let Some(ss) = st.sketch(sid) else { return };
     let sk = &ss.sketch;
+    let locked = sk.locked_points();
     for (i, p) in sk.points.iter().enumerate() {
         if !solvecraft_engine::view::sketch_point_visible(sk, i) {
             continue;
         }
         let Some(sp) = proj.to_screen(ss.plane.to_world(p.pos)) else { continue };
         let det = ss.report.point_determined.get(i).copied().unwrap_or(false);
-        let c = if det { t.sketch_point } else { t.sketch_point_free };
+        let c = if p.link.is_none() && locked.get(i).copied().unwrap_or(false) {
+            t.sketch_locked
+        } else if det {
+            t.sketch_point
+        } else {
+            t.sketch_point_free
+        };
         if i == 0 {
             painter.circle(sp, 3.5, Color32::from_rgb(240, 200, 60), Stroke::new(1.0, t.body_edge));
         } else {