feat(topola-egui): Add progress bar for the currently routed ratline

The capability to measure progress will later be useful to choose slower
but better optimization strategies if more time is available.

crates/topola-egui/src/status_bar.rs

@@ -4,7 +4,7 @@
 
 use std::ops::ControlFlow;
 
-use topola::interactor::activity::ActivityStepperWithStatus;
+use topola::{interactor::activity::ActivityStepperWithStatus, stepper::EstimateProgress};
 
 use crate::{translator::Translator, viewport::Viewport};
 
@@ -38,6 +38,20 @@ impl StatusBar {
                 "x: {} y: {} \t {}",
                 latest_pos.x, -latest_pos.y, message
             ));
+
+            if let Some(activity) = maybe_activity {
+                let value = activity.estimate_progress_value();
+                let maximum = activity.estimate_progress_maximum();
+
+                ui.add(
+                    egui::ProgressBar::new((value / maximum) as f32).text(format!(
+                        "{:.1} ({:.1}/{:.1})",
+                        value / maximum * 100.0,
+                        value,
+                        maximum
+                    )),
+                );
+            }
         });
     }
 }

crates/topola-egui/src/viewport.rs

@@ -376,7 +376,6 @@ impl Viewport {
                                         };
 
                                         if menu_bar.show_pathfinding_scores {
-                                            //TODO "{astar.scores[index]} ({astar.estimate_scores[index]}) (...)"
                                             let score_text = thetastar
                                                 .scores()
                                                 .get(&navnode)
@@ -384,7 +383,7 @@ impl Viewport {
                                                     format!("g={:.2}", s)
                                                 });
                                             let estimate_score_text = thetastar
-                                                .estimate_scores()
+                                                .cost_to_goal_estimate_scores()
                                                 .get(&navnode)
                                                 .map_or_else(String::new, |s| {
                                                     format!("(f={:.2})", s)

src/autorouter/autoroute.rs

@@ -17,7 +17,7 @@ use crate::{
     router::{
         navcord::Navcord, navmesh::Navmesh, thetastar::ThetastarStepper, RouteStepper, Router,
     },
-    stepper::Step,
+    stepper::{EstimateProgress, Step},
 };
 
 use super::{invoker::GetDebugOverlayData, Autorouter, AutorouterError, AutorouterOptions};
@@ -164,6 +164,22 @@ impl<M: AccessMesadata> Step<Autorouter<M>, Option<LayoutEdit>, AutorouteContinu
     }
 }
 
+impl EstimateProgress for AutorouteExecutionStepper {
+    type Value = f64;
+
+    fn estimate_progress_value(&self) -> f64 {
+        self.route
+            .as_ref()
+            .map_or(0.0, |route| route.estimate_progress_value())
+    }
+
+    fn estimate_progress_maximum(&self) -> f64 {
+        self.route
+            .as_ref()
+            .map_or(0.0, |route| route.estimate_progress_maximum())
+    }
+}
+
 impl GetDebugOverlayData for AutorouteExecutionStepper {
     fn maybe_thetastar(&self) -> Option<&ThetastarStepper<Navmesh, f64>> {
         self.route.as_ref().map(|route| route.thetastar())

src/autorouter/compare_detours.rs

@@ -15,7 +15,7 @@ use crate::{
     geometry::{primitive::PrimitiveShape, shape::MeasureLength},
     graph::MakeRef,
     router::{navcord::Navcord, navmesh::Navmesh, thetastar::ThetastarStepper},
-    stepper::Step,
+    stepper::{EstimateProgress, Step},
 };
 
 use super::{
@@ -100,6 +100,10 @@ impl<M: AccessMesadata> Step<Autorouter<M>, (f64, f64)> for CompareDetoursExecut
     }
 }
 
+impl EstimateProgress for CompareDetoursExecutionStepper {
+    type Value = f64;
+}
+
 impl GetDebugOverlayData for CompareDetoursExecutionStepper {
     fn maybe_thetastar(&self) -> Option<&ThetastarStepper<Navmesh, f64>> {
         self.autoroute.maybe_thetastar()

src/autorouter/execution.rs

@@ -11,7 +11,7 @@ use crate::{
     board::AccessMesadata,
     layout::{via::ViaWeight, LayoutEdit},
     router::ng,
-    stepper::{Abort, Step},
+    stepper::{Abort, EstimateProgress, Step},
 };
 
 use super::{
@@ -165,3 +165,39 @@ impl<M: AccessMesadata + Clone> Abort<Invoker<M>> for ExecutionStepper<M> {
         }
     }
 }
+
+// Since enum_dispatch does not really support generics, we implement this the
+// long way.
+impl<M> EstimateProgress for ExecutionStepper<M> {
+    type Value = f64;
+
+    fn estimate_progress_value(&self) -> f64 {
+        match self {
+            ExecutionStepper::Autoroute(autoroute) => autoroute.estimate_progress_value(),
+            ExecutionStepper::TopoAutoroute(toporoute) => toporoute.estimate_progress_value(),
+            ExecutionStepper::PlaceVia(place_via) => place_via.estimate_progress_value(),
+            ExecutionStepper::RemoveBands(remove_bands) => remove_bands.estimate_progress_value(),
+            ExecutionStepper::CompareDetours(compare_detours) => {
+                compare_detours.estimate_progress_value()
+            }
+            ExecutionStepper::MeasureLength(measure_length) => {
+                measure_length.estimate_progress_value()
+            }
+        }
+    }
+
+    fn estimate_progress_maximum(&self) -> f64 {
+        match self {
+            ExecutionStepper::Autoroute(autoroute) => autoroute.estimate_progress_maximum(),
+            ExecutionStepper::TopoAutoroute(toporoute) => toporoute.estimate_progress_maximum(),
+            ExecutionStepper::PlaceVia(place_via) => place_via.estimate_progress_maximum(),
+            ExecutionStepper::RemoveBands(remove_bands) => remove_bands.estimate_progress_maximum(),
+            ExecutionStepper::CompareDetours(compare_detours) => {
+                compare_detours.estimate_progress_maximum()
+            }
+            ExecutionStepper::MeasureLength(measure_length) => {
+                measure_length.estimate_progress_maximum()
+            }
+        }
+    }
+}

src/autorouter/invoker.rs

@@ -150,10 +150,10 @@ impl<M: AccessMesadata + Clone> Invoker<M> {
         }
     }
 
-    #[debug_requires(self.ongoing_command.is_none())]
     /// Pass given command to be executed.
     ///
     /// Function used to set given [`Command`] to ongoing state, dispatch and execute it.
+    #[debug_requires(self.ongoing_command.is_none())]
     pub fn execute_stepper(
         &mut self,
         command: Command,

src/autorouter/measure_length.rs

@@ -8,6 +8,7 @@
 
 use crate::{
     board::AccessMesadata, geometry::shape::MeasureLength as MeasureLengthTrait, graph::MakeRef,
+    stepper::EstimateProgress,
 };
 
 use super::{invoker::GetDebugOverlayData, selection::BandSelection, Autorouter, AutorouterError};
@@ -47,4 +48,7 @@ impl MeasureLengthExecutionStepper {
     }
 }
 
+impl EstimateProgress for MeasureLengthExecutionStepper {
+    type Value = f64;
+}
 impl GetDebugOverlayData for MeasureLengthExecutionStepper {}

src/autorouter/place_via.rs

@@ -9,6 +9,7 @@
 use crate::{
     board::AccessMesadata,
     layout::{via::ViaWeight, LayoutEdit},
+    stepper::EstimateProgress,
 };
 
 use super::{invoker::GetDebugOverlayData, Autorouter, AutorouterError};
@@ -46,4 +47,7 @@ impl PlaceViaExecutionStepper {
     }
 }
 
+impl EstimateProgress for PlaceViaExecutionStepper {
+    type Value = f64;
+}
 impl GetDebugOverlayData for PlaceViaExecutionStepper {}

src/autorouter/remove_bands.rs

@@ -4,7 +4,7 @@
 
 //! Provides functionality to remove bands from the layout.
 
-use crate::{board::AccessMesadata, layout::LayoutEdit};
+use crate::{board::AccessMesadata, layout::LayoutEdit, stepper::EstimateProgress};
 
 use super::{invoker::GetDebugOverlayData, selection::BandSelection, Autorouter, AutorouterError};
 
@@ -44,4 +44,7 @@ impl RemoveBandsExecutionStepper {
     }
 }
 
+impl EstimateProgress for RemoveBandsExecutionStepper {
+    type Value = f64;
+}
 impl GetDebugOverlayData for RemoveBandsExecutionStepper {}

src/interactor/activity.rs

@@ -25,7 +25,7 @@ use crate::{
         ng,
         thetastar::ThetastarStepper,
     },
-    stepper::{Abort, OnEvent, Step},
+    stepper::{Abort, EstimateProgress, OnEvent, Step},
 };
 
 /// Stores the interactive input data from the user.
@@ -98,6 +98,26 @@ impl<M: AccessMesadata + Clone> Abort<Invoker<M>> for ActivityStepper<M> {
     }
 }
 
+// Since enum_dispatch does not really support generics, we implement this the
+// long way.
+impl<M> EstimateProgress for ActivityStepper<M> {
+    type Value = f64;
+
+    fn estimate_progress_value(&self) -> f64 {
+        match self {
+            ActivityStepper::Interaction(..) => 0.0,
+            ActivityStepper::Execution(execution) => execution.estimate_progress_value(),
+        }
+    }
+
+    fn estimate_progress_maximum(&self) -> f64 {
+        match self {
+            ActivityStepper::Interaction(..) => 0.0,
+            ActivityStepper::Execution(execution) => execution.estimate_progress_maximum(),
+        }
+    }
+}
+
 impl<M: AccessMesadata> OnEvent<ActivityContext<'_, M>, InteractiveEvent> for ActivityStepper<M> {
     type Output = Result<(), InteractionError>;
 
@@ -179,6 +199,18 @@ impl<M: AccessMesadata + Clone> OnEvent<ActivityContext<'_, M>, InteractiveEvent
     }
 }
 
+impl<M> EstimateProgress for ActivityStepperWithStatus<M> {
+    type Value = f64;
+
+    fn estimate_progress_value(&self) -> f64 {
+        self.activity.estimate_progress_value()
+    }
+
+    fn estimate_progress_maximum(&self) -> f64 {
+        self.activity.estimate_progress_maximum()
+    }
+}
+
 impl<M> GetDebugOverlayData for ActivityStepperWithStatus<M> {
     fn maybe_thetastar(&self) -> Option<&ThetastarStepper<Navmesh, f64>> {
         self.activity.maybe_thetastar()

src/router/ng/router.rs

@@ -15,7 +15,7 @@ use crate::{
     geometry::primitive::PrimitiveShape,
     graph::GenericIndex,
     layout::{poly::PolyWeight, Layout, LayoutEdit},
-    stepper::Abort,
+    stepper::{Abort, EstimateProgress},
 };
 
 use super::{
@@ -232,6 +232,10 @@ impl<R: AccessRules + Clone + std::panic::RefUnwindSafe> AutorouteExecutionStepp
     }
 }
 
+impl<M> EstimateProgress for AutorouteExecutionStepper<M> {
+    type Value = f64;
+}
+
 impl<M> GetDebugOverlayData for AutorouteExecutionStepper<M> {
     fn maybe_topo_navmesh(&self) -> Option<pie::navmesh::NavmeshRef<'_, super::PieNavmeshBase>> {
         Some(pie::navmesh::NavmeshRef {

src/router/route.rs

@@ -19,7 +19,7 @@ use crate::{
         thetastar::{ThetastarError, ThetastarStepper},
         Router, RouterThetastarStrategy,
     },
-    stepper::Step,
+    stepper::{EstimateProgress, Step},
 };
 
 #[derive(Getters, Dissolve)]
@@ -80,6 +80,7 @@ impl<R: AccessRules> Step<Router<'_, R>, BandTermsegIndex> for RouteStepper {
         let target = self.thetastar.graph().destination();
         let mut strategy = RouterThetastarStrategy::new(layout, &mut self.navcord, target);
         let result = self.thetastar.step(&mut strategy);
+
         self.ghosts = strategy.probe_ghosts;
         self.obstacles = strategy.probe_obstacles;
 
@@ -97,3 +98,15 @@ impl<R: AccessRules> Step<Router<'_, R>, BandTermsegIndex> for RouteStepper {
         }
     }
 }
+
+impl EstimateProgress for RouteStepper {
+    type Value = f64;
+
+    fn estimate_progress_value(&self) -> f64 {
+        self.thetastar.estimate_progress_value()
+    }
+
+    fn estimate_progress_maximum(&self) -> f64 {
+        self.thetastar.estimate_progress_maximum()
+    }
+}

src/router/router.rs

@@ -119,7 +119,7 @@ impl<R: AccessRules> ThetastarStrategy<Navmesh, f64, BandTermsegIndex>
         self.navcord.step_back(self.layout);
     }
 
-    fn estimate_cost(&mut self, navmesh: &Navmesh, vertex: NavnodeIndex) -> f64 {
+    fn estimate_cost_to_goal(&mut self, navmesh: &Navmesh, vertex: NavnodeIndex) -> f64 {
         let start_point = PrimitiveIndex::from(navmesh.node_weight(vertex).unwrap().node)
             .primitive(self.layout.drawing())
             .shape()

src/router/thetastar.rs

@@ -11,7 +11,7 @@
 use std::collections::btree_map::Entry;
 use std::collections::{BTreeMap, BinaryHeap};
 
-use std::ops::ControlFlow;
+use std::ops::{ControlFlow, Sub};
 
 use derive_getters::Getters;
 use petgraph::algo::Measure;
@@ -20,7 +20,7 @@ use thiserror::Error;
 
 use std::cmp::Ordering;
 
-use crate::stepper::Step;
+use crate::stepper::{EstimateProgress, Step};
 
 #[derive(Copy, Clone, Debug)]
 pub struct MinScored<K, T>(pub K, pub T);
@@ -122,7 +122,7 @@ where
     ) -> Result<Option<R>, ()>;
     fn place_probe_to_navnode<'a>(&mut self, graph: &'a G, probed_navnode: G::NodeId) -> Option<K>;
     fn remove_probe(&mut self, graph: &G);
-    fn estimate_cost(&mut self, graph: &G, navnode: G::NodeId) -> K;
+    fn estimate_cost_to_goal(&mut self, graph: &G, navnode: G::NodeId) -> K;
 }
 
 pub trait MakeEdgeRef: IntoEdgeReferences {
@@ -155,21 +155,28 @@ where
     G: GraphBase,
     G::NodeId: Eq + Ord,
     for<'a> &'a G: IntoEdges<NodeId = G::NodeId, EdgeId = G::EdgeId> + MakeEdgeRef,
-    K: Measure + Copy,
+    K: Measure + Copy + Sub<Output = K>,
 {
     state: ThetastarState<G::NodeId, G::EdgeId>,
     graph: G,
+    /// The priority queue of the navnodes to expand.
     #[getter(skip)]
-    visit_next: BinaryHeap<MinScored<K, G::NodeId>>,
+    frontier: BinaryHeap<MinScored<K, G::NodeId>>,
     /// Also known as the g-scores, or just g.
     scores: BTreeMap<G::NodeId, K>,
     /// Also known as the f-scores, or just f.
-    estimate_scores: BTreeMap<G::NodeId, K>,
+    cost_to_goal_estimate_scores: BTreeMap<G::NodeId, K>,
     #[getter(skip)]
     path_tracker: PathTracker<G>,
     // FIXME: To work around edge references borrowing from the graph we collect then reiterate over them.
     #[getter(skip)]
     edge_ids: Vec<G::EdgeId>,
+
+    #[getter(skip)]
+    progress_estimate_value: K,
+
+    #[getter(skip)]
+    progress_estimate_maximum: K,
 }
 
 #[derive(Error, Debug, Clone)]
@@ -183,29 +190,55 @@ where
     G: GraphBase,
     G::NodeId: Eq + Ord,
     for<'a> &'a G: IntoEdges<NodeId = G::NodeId, EdgeId = G::EdgeId> + MakeEdgeRef,
-    K: Measure + Copy,
+    K: Measure + Copy + Sub<Output = K>,
 {
     pub fn new<R>(
         graph: G,
         start: G::NodeId,
         strategy: &mut impl ThetastarStrategy<G, K, R>,
     ) -> Self {
+        let estimated_cost_from_start_to_goal = strategy.estimate_cost_to_goal(&graph, start);
+
         let mut this = Self {
             state: ThetastarState::Scanning,
             graph,
-            visit_next: BinaryHeap::new(),
+            frontier: BinaryHeap::new(),
             scores: BTreeMap::new(),
-            estimate_scores: BTreeMap::new(),
+            cost_to_goal_estimate_scores: BTreeMap::new(),
             path_tracker: PathTracker::<G>::new(),
             edge_ids: Vec::new(),
+            progress_estimate_value: K::default(),
+            progress_estimate_maximum: estimated_cost_from_start_to_goal,
         };
 
         let zero_score = K::default();
         this.scores.insert(start, zero_score);
-        this.visit_next
+        this.frontier
-            .push(MinScored(strategy.estimate_cost(&this.graph, start), start));
+            .push(MinScored(estimated_cost_from_start_to_goal, start));
         this
     }
+
+    fn push_to_frontier<R>(
+        &mut self,
+        next: G::NodeId,
+        next_score: K,
+        predecessor: G::NodeId,
+        strategy: &mut impl ThetastarStrategy<G, K, R>,
+    ) {
+        let cost_to_goal_estimate = strategy.estimate_cost_to_goal(&self.graph, next);
+
+        if cost_to_goal_estimate > self.progress_estimate_maximum {
+            self.progress_estimate_maximum = cost_to_goal_estimate;
+        }
+
+        if self.progress_estimate_maximum - cost_to_goal_estimate > self.progress_estimate_value {
+            self.progress_estimate_value = self.progress_estimate_maximum - cost_to_goal_estimate;
+        }
+
+        self.path_tracker.set_predecessor(next, predecessor);
+        let next_estimate_score = next_score + cost_to_goal_estimate;
+        self.frontier.push(MinScored(next_estimate_score, next));
+    }
 }
 
 impl<G, K, R, S: ThetastarStrategy<G, K, R>>
@@ -214,7 +247,7 @@ where
     G: GraphBase,
     G::NodeId: Eq + Ord,
     for<'a> &'a G: IntoEdges<NodeId = G::NodeId, EdgeId = G::EdgeId> + MakeEdgeRef,
-    K: Measure + Copy,
+    K: Measure + Copy + Sub<Output = K>,
 {
     type Error = ThetastarError;
 
@@ -227,7 +260,7 @@ where
     > {
         match self.state {
             ThetastarState::Scanning => {
-                let Some(MinScored(estimate_score, navnode)) = self.visit_next.pop() else {
+                let Some(MinScored(estimate_score, navnode)) = self.frontier.pop() else {
                     return Err(ThetastarError::NotFound);
                 };
 
@@ -243,7 +276,7 @@ where
                     return Ok(ControlFlow::Break((cost, path, result)));
                 }
 
-                match self.estimate_scores.entry(navnode) {
+                match self.cost_to_goal_estimate_scores.entry(navnode) {
                     Entry::Occupied(mut entry) => {
                         // If the node has already been visited with an equal or lower
                         // estimated score than now, then we do not need to re-visit it.
@@ -299,10 +332,7 @@ where
                                 }
                             }
 
-                            self.path_tracker.set_predecessor(next, parent_navnode);
+                            self.push_to_frontier(next, next_score, parent_navnode, strategy);
-                            let next_estimate_score =
-                                next_score + strategy.estimate_cost(&self.graph, next);
-                            self.visit_next.push(MinScored(next_estimate_score, next));
 
                             self.state = ThetastarState::Probing(visited_navnode);
                             Ok(ControlFlow::Continue(self.state))
@@ -353,10 +383,7 @@ where
                         }
                     }
 
-                    self.path_tracker.set_predecessor(next, visited_navnode);
+                    self.push_to_frontier(next, next_score, visited_navnode, strategy);
-                    let next_estimate_score =
-                        next_score + strategy.estimate_cost(&self.graph, next);
-                    self.visit_next.push(MinScored(next_estimate_score, next));
 
                     self.state = ThetastarState::Probing(visited_navnode);
                     Ok(ControlFlow::Continue(self.state))
@@ -374,3 +401,21 @@ where
         }
     }
 }
+
+impl<G, K> EstimateProgress for ThetastarStepper<G, K>
+where
+    G: GraphBase,
+    G::NodeId: Eq + Ord,
+    for<'a> &'a G: IntoEdges<NodeId = G::NodeId, EdgeId = G::EdgeId> + MakeEdgeRef,
+    K: Measure + Copy + Sub<Output = K>,
+{
+    type Value = K;
+
+    fn estimate_progress_value(&self) -> K {
+        self.progress_estimate_value
+    }
+
+    fn estimate_progress_maximum(&self) -> K {
+        self.progress_estimate_maximum
+    }
+}

src/stepper.rs

@@ -11,14 +11,14 @@ use core::ops::ControlFlow;
 ///
 /// An object that implements this trait is called a "stepper".
 ///
-/// Steppers always progress linearly, that is, it is presumed that the context
+/// Steppers always progress linearly and their future states are determined by
-/// does not change between calls in a way that can affect the stepper's future
+/// the initial state. It is assumed that the changes in context cannot change
-/// states. Advanceable data structures designed for uses where the future state
+/// the stepper's execution. Advanceable data structures designed for uses where
-/// intentionally *may* change from the information supplied as arguments are
+/// the future state intentionally *may* change from the information supplied
-/// not considered steppers. An example of such an advanceable non-stepper is
+/// after initialization are not considered steppers. An example of such an
-/// the [`Navcord`](crate::router::navcord::Navcord) struct, as it does not progress
+/// advanceable non-stepper is the [`Navcord`] (crate::router::navcord::Navcord)
-/// linearly because it branches out by on each call taking in a
+/// struct, as it does not progress linearly because it branches out on each
-/// changeable `to` argument that affects the future states.
+/// call by taking in a changeable `to` argument that affects the future states.
 ///
 /// Petgraph's counterpart of this trait is its
 /// [`petgraph::visit::Walker<Context>`] trait.
@@ -53,9 +53,25 @@ pub trait Abort<C> {
     fn abort(&mut self, context: &mut C);
 }
 
-/// Steppers that may receive discrete events and act on them, implement this trait.
+/// Steppers that can receive discrete events and act on them, implement this
+/// trait.
+// XXX: Doesn't this violate the rule that stepper's future states are
+// determined by its initial state?
 pub trait OnEvent<Ctx, Event> {
     type Output;
 
     fn on_event(&mut self, context: &mut Ctx, event: Event) -> Self::Output;
 }
+
+/// Some steppers report estimates of how far they are from completion.
+pub trait EstimateProgress {
+    type Value: Default;
+
+    fn estimate_progress_value(&self) -> Self::Value {
+        Self::Value::default()
+    }
+
+    fn estimate_progress_maximum(&self) -> Self::Value {
+        Self::Value::default()
+    }
+}