feat(autorouter/anterouter): Fanout only in cardinal directions

This works around the falsely positively fillet exclusions our current
navmesh creation method causes.

src/autorouter/anterouter.rs

@@ -10,7 +10,7 @@ use rstar::{Envelope, RTreeObject, AABB};
 use specctra_core::mesadata::AccessMesadata;
 
 use crate::{
-    autorouter::{compass_direction::CompassDirection8, ratline::RatlineIndex, Autorouter},
+    autorouter::{compass_direction::CardinalDirection, ratline::RatlineIndex, Autorouter},
     board::edit::BoardEdit,
     drawing::{
         dot::FixedDotIndex,
@@ -18,12 +18,8 @@ use crate::{
         primitive::MakePrimitiveShape,
     },
     geometry::{GenericNode, GetLayer},
-    graph::{GenericIndex, GetIndex, MakeRef},
-    layout::{
-        poly::{MakePolygon, PolyWeight},
-        via::ViaWeight,
-        CompoundWeight,
-    },
+    graph::MakeRef,
+    layout::{poly::MakePolygon, via::ViaWeight},
     math::Circle,
 };
 
@@ -120,7 +116,7 @@ impl Anterouter {
             ratline_delta = -ratline_delta;
         }
 
-        let initial_compass_direction8 = CompassDirection8::nearest_to_vector(ratline_delta);
+        let cardinal_direction = CardinalDirection::nearest_to_vector(ratline_delta);
 
         if self
             .anteroute_fanout_to_anchor(
@@ -128,15 +124,15 @@ impl Anterouter {
                 ratvertex,
                 source_dot,
                 target_layer,
-                Point::from(initial_compass_direction8) * 1.2,
+                Point::from(cardinal_direction) * 1.4,
             )
             .is_ok()
         {
             return;
         }
 
-        let mut counterclockwise_turning = initial_compass_direction8;
-        let mut clockwise_turning = initial_compass_direction8;
+        let mut counterclockwise_turning = cardinal_direction;
+        let mut clockwise_turning = cardinal_direction;
 
         loop {
             counterclockwise_turning = counterclockwise_turning.turn_counterclockwise();
@@ -147,7 +143,7 @@ impl Anterouter {
                     ratvertex,
                     source_dot,
                     target_layer,
-                    Point::from(counterclockwise_turning) * 1.2,
+                    Point::from(counterclockwise_turning) * 1.4,
                 )
                 .is_ok()
             {
@@ -162,15 +158,15 @@ impl Anterouter {
                     ratvertex,
                     source_dot,
                     target_layer,
-                    Point::from(clockwise_turning) * 1.2,
+                    Point::from(clockwise_turning) * 1.4,
                 )
                 .is_ok()
             {
                 return;
             }
 
-            if counterclockwise_turning == initial_compass_direction8
-                || clockwise_turning == initial_compass_direction8
+            if counterclockwise_turning == cardinal_direction
+                || clockwise_turning == cardinal_direction
             {
                 break;
                 //panic!();
@@ -211,25 +207,7 @@ impl Anterouter {
             .primitive(dot)
             .maybe_net();
 
-        let pin_bbox = if let Some(poly) = autorouter
-            .board()
-            .layout()
-            .drawing()
-            .compounds(GenericIndex::<()>::new(dot.index()))
-            .find_map(|(_, compound)| {
-                if let CompoundWeight::Poly(_) = autorouter
-                    .board()
-                    .layout()
-                    .drawing()
-                    .compound_weight(compound)
-                {
-                    Some(compound)
-                } else {
-                    None
-                }
-            })
-            .map(|compound| GenericIndex::<PolyWeight>::new(compound.index()))
-        {
+        let pin_bbox = if let Some(poly) = autorouter.board().layout().primitive_poly(dot.into()) {
             let bbox = poly.ref_(autorouter.board().layout()).shape().envelope();
             AABB::<[f64; 2]>::from_corners(
                 [bbox.lower().x(), bbox.lower().y()],

src/autorouter/compass_direction.rs

@@ -1,11 +1,66 @@
 // SPDX-FileCopyrightText: 2025 Topola contributors
 //
-// SPDX-License-Identifier: MIT OR Apache-2.0
+// SPDX-License-Identifier: MIT
 
 use geo::Point;
 
 #[derive(Clone, Copy, Debug, Eq, PartialEq)]
-pub enum CompassDirection8 {
+pub enum CardinalDirection {
+    North,
+    West,
+    South,
+    East,
+}
+
+impl From<CardinalDirection> for Point {
+    fn from(compass_direction: CardinalDirection) -> Point {
+        match compass_direction {
+            CardinalDirection::North => [0.0, -1.0].into(),
+            CardinalDirection::West => [-1.0, 0.0].into(),
+            CardinalDirection::South => [0.0, 1.0].into(),
+            CardinalDirection::East => [1.0, 0.0].into(),
+        }
+    }
+}
+
+impl CardinalDirection {
+    pub fn nearest_to_vector(vector: Point) -> Self {
+        if vector.x().abs() > vector.y().abs() {
+            if vector.x() > 0.0 {
+                Self::East
+            } else {
+                Self::West
+            }
+        } else {
+            if vector.y() > 0.0 {
+                Self::North
+            } else {
+                Self::South
+            }
+        }
+    }
+
+    pub fn turn_counterclockwise(self) -> Self {
+        match self {
+            Self::North => Self::West,
+            Self::West => Self::South,
+            Self::South => Self::East,
+            Self::East => Self::North,
+        }
+    }
+
+    pub fn turn_clockwise(self) -> Self {
+        match self {
+            Self::North => Self::East,
+            Self::East => Self::South,
+            Self::South => Self::West,
+            Self::West => Self::North,
+        }
+    }
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum PrincipalWind {
     North,
     NorthWest,
     West,
@@ -16,52 +71,41 @@ pub enum CompassDirection8 {
     NorthEast,
 }
 
-impl From<CompassDirection8> for Point {
-    fn from(compass_direction8: CompassDirection8) -> Point {
-        match compass_direction8 {
-            CompassDirection8::North => [0.0, -1.0].into(),
-            CompassDirection8::NorthWest => [-1.0, -1.0].into(),
-            CompassDirection8::West => [-1.0, 0.0].into(),
-            CompassDirection8::SouthWest => [-1.0, 1.0].into(),
-            CompassDirection8::South => [0.0, 1.0].into(),
-            CompassDirection8::SouthEast => [1.0, 1.0].into(),
-            CompassDirection8::East => [1.0, 0.0].into(),
-            CompassDirection8::NorthEast => [1.0, -1.0].into(),
+impl From<PrincipalWind> for Point {
+    fn from(principal_wind: PrincipalWind) -> Point {
+        match principal_wind {
+            PrincipalWind::North => [0.0, -1.0].into(),
+            PrincipalWind::NorthWest => [-1.0, -1.0].into(),
+            PrincipalWind::West => [-1.0, 0.0].into(),
+            PrincipalWind::SouthWest => [-1.0, 1.0].into(),
+            PrincipalWind::South => [0.0, 1.0].into(),
+            PrincipalWind::SouthEast => [1.0, 1.0].into(),
+            PrincipalWind::East => [1.0, 0.0].into(),
+            PrincipalWind::NorthEast => [1.0, -1.0].into(),
         }
     }
 }
 
-impl CompassDirection8 {
+impl PrincipalWind {
     pub fn nearest_to_vector(vector: Point) -> Self {
-        /*match (vector.x().signum(), vector.y().signum()) {
-            (0.0, -1.0) => Self::North,
-            (-1.0, -1.0) => Self::NorthWest,
-            (-1.0, 0.0) => Self::West,
-            (-1.0, 1.0) => Self::SouthWest,
-            (0.0, 1.0) => Self::South,
-            (1.0, 1.0) => Self::SouthEast,
-            (1.0, 0.0) => Self::East,
-            (1.0, -1.0) => Self::NorthEast,
-            (_, _) => panic!(),
-        }*/
         if vector.x() == 0.0 && vector.y() == 0.0 {
             panic!("Zero vector has no direction");
         }
 
-        let angle = vector.y().atan2(vector.x()); // atan2 gives angle in radians from -π to π
-        let angle_deg = angle.to_degrees(); // Convert to degrees for easier reasoning
-        let compass_angle = (450.0 - angle_deg) % 360.0; // Convert to compass heading (0° = North)
+        let angle = vector.y().atan2(vector.x()); // atan2 gives angle in radians from -pi to pi.
+        let angle_deg = angle.to_degrees(); // Convert to degrees for easier reasoning.
+        let compass_angle = (450.0 - angle_deg) % 360.0; // Convert to compass heading (0 deg = North).
 
-        // Each direction is 45 degrees wide; round to nearest
+        // Each direction is 45 degrees wide; round to nearest.
         match ((compass_angle + 22.5) / 45.0).floor() as i32 % 8 {
-            0 => CompassDirection8::North,
-            1 => CompassDirection8::NorthEast,
-            2 => CompassDirection8::East,
-            3 => CompassDirection8::SouthEast,
-            4 => CompassDirection8::South,
-            5 => CompassDirection8::SouthWest,
-            6 => CompassDirection8::West,
-            7 => CompassDirection8::NorthWest,
+            0 => PrincipalWind::North,
+            1 => PrincipalWind::NorthEast,
+            2 => PrincipalWind::East,
+            3 => PrincipalWind::SouthEast,
+            4 => PrincipalWind::South,
+            5 => PrincipalWind::SouthWest,
+            6 => PrincipalWind::West,
+            7 => PrincipalWind::NorthWest,
             _ => unreachable!(),
         }
     }

src/geometry/with_rtree.rs

@@ -465,7 +465,9 @@ impl<
     where
         I: Copy + GetIndex,
     {
-        self.geometry.add_to_compound(primitive, label, compound);
+        todo!();
+        // This is incorrect: R-tree bbox is not updated.
+        //self.geometry.add_to_compound(primitive, label, compound);
     }
 
     fn compound_weight(&self, compound: GenericIndex<CW>) -> &CW {

src/layout/layout.rs

@@ -347,6 +347,19 @@ impl<R: AccessRules> Layout<R> {
         }
     }
 
+    pub fn primitive_poly(&self, primitive: PrimitiveIndex) -> Option<GenericIndex<PolyWeight>> {
+        self.drawing()
+            .compounds(GenericIndex::<()>::new(primitive.index()))
+            .find_map(|(_, compound)| {
+                if let CompoundWeight::Poly(_) = self.drawing().compound_weight(compound) {
+                    Some(compound)
+                } else {
+                    None
+                }
+            })
+            .map(|compound| GenericIndex::<PolyWeight>::new(compound.index()))
+    }
+
     /// Checks if a node is not a primitive part of a compound, and if yes, returns its apex and center
     pub fn apex_of_compoundless_node(
         &self,