From 61f246213fd3df76277601d9e705cfc6a8a2f9bd Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Wed, 27 Mar 2024 13:30:27 +0100
Subject: [PATCH] Provide surface to `Cycle::winding`

---
 crates/fj-core/src/operations/sweep/sketch.rs        | 2 +-
 crates/fj-core/src/topology/objects/cycle.rs         | 4 +++-
 crates/fj-core/src/topology/objects/face.rs          | 2 +-
 crates/fj-core/src/validate/sketch.rs                | 6 ++++--
 crates/fj-core/src/validation/checks/face_winding.rs | 4 ++--
 5 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/crates/fj-core/src/operations/sweep/sketch.rs b/crates/fj-core/src/operations/sweep/sketch.rs
index 446fa1a90..e2888db5a 100644
--- a/crates/fj-core/src/operations/sweep/sketch.rs
+++ b/crates/fj-core/src/operations/sweep/sketch.rs
@@ -42,7 +42,7 @@ impl SweepSketch for Sketch {
                 // clockwise. Let's check that real quick.
                 assert!(region
                     .exterior()
-                    .winding(&core.layers.geometry)
+                    .winding(&core.layers.geometry, self.surface())
                     .is_ccw());
 
                 let is_negative_sweep = {
diff --git a/crates/fj-core/src/topology/objects/cycle.rs b/crates/fj-core/src/topology/objects/cycle.rs
index ea55d8f8f..032a3e4b8 100644
--- a/crates/fj-core/src/topology/objects/cycle.rs
+++ b/crates/fj-core/src/topology/objects/cycle.rs
@@ -6,6 +6,8 @@ use crate::{
     topology::{HalfEdge, ObjectSet},
 };
 
+use super::surface::Surface;
+
 /// A cycle of connected edges
 #[derive(Clone, Debug)]
 pub struct Cycle {
@@ -29,7 +31,7 @@ impl Cycle {
     /// Please note that this is not *the* winding of the cycle, only one of the
     /// two possible windings, depending on the direction you look at the
     /// surface that the cycle is defined on from.
-    pub fn winding(&self, geometry: &Geometry) -> Winding {
+    pub fn winding(&self, geometry: &Geometry, _: &Handle<Surface>) -> Winding {
         // The cycle could be made up of one or two circles. If that is the
         // case, the winding of the cycle is determined by the winding of the
         // first circle.
diff --git a/crates/fj-core/src/topology/objects/face.rs b/crates/fj-core/src/topology/objects/face.rs
index 919d635bf..e1e6ab883 100644
--- a/crates/fj-core/src/topology/objects/face.rs
+++ b/crates/fj-core/src/topology/objects/face.rs
@@ -63,7 +63,7 @@ impl Face {
     /// back sides. The front side is the side, where the face's exterior cycle
     /// is wound counter-clockwise.
     pub fn coord_handedness(&self, geometry: &Geometry) -> Handedness {
-        match self.region.exterior().winding(geometry) {
+        match self.region.exterior().winding(geometry, self.surface()) {
             Winding::Ccw => Handedness::RightHanded,
             Winding::Cw => Handedness::LeftHanded,
         }
diff --git a/crates/fj-core/src/validate/sketch.rs b/crates/fj-core/src/validate/sketch.rs
index 5e536c5f7..150a66833 100644
--- a/crates/fj-core/src/validate/sketch.rs
+++ b/crates/fj-core/src/validate/sketch.rs
@@ -77,7 +77,7 @@ impl SketchValidationError {
     ) {
         sketch.regions().iter().for_each(|region| {
             let cycle = region.exterior();
-            if cycle.winding(geometry) == Winding::Cw {
+            if cycle.winding(geometry, sketch.surface()) == Winding::Cw {
                 errors.push(ValidationError::Sketch(
                     SketchValidationError::ClockwiseExteriorCycle {
                         cycle: cycle.clone(),
@@ -97,7 +97,9 @@ impl SketchValidationError {
             region
                 .interiors()
                 .iter()
-                .filter(|interior| interior.winding(geometry) == Winding::Ccw)
+                .filter(|interior| {
+                    interior.winding(geometry, sketch.surface()) == Winding::Ccw
+                })
                 .for_each(|cycle| {
                     errors.push(ValidationError::Sketch(
                         SketchValidationError::CounterClockwiseInteriorCycle {
diff --git a/crates/fj-core/src/validation/checks/face_winding.rs b/crates/fj-core/src/validation/checks/face_winding.rs
index d60f4cbc6..ee049d1fe 100644
--- a/crates/fj-core/src/validation/checks/face_winding.rs
+++ b/crates/fj-core/src/validation/checks/face_winding.rs
@@ -53,8 +53,8 @@ impl ValidationCheck<Face> for InteriorCycleHasInvalidWinding {
                 return None;
             }
 
-            let exterior_winding = exterior.winding(geometry);
-            let interior_winding = interior.winding(geometry);
+            let exterior_winding = exterior.winding(geometry, object.surface());
+            let interior_winding = interior.winding(geometry, object.surface());
 
             if exterior_winding == interior_winding {
                 return Some(InteriorCycleHasInvalidWinding {