From 1be782b88d499c7e058e7cfe78db3707170e4d7a Mon Sep 17 00:00:00 2001
From: Tanner Collin <git@tannercollin.com>
Date: Wed, 18 Feb 2026 12:23:29 -0700
Subject: [PATCH] fix: Improve face creation from edges using
 BRepOffsetAPI_MakeFilling

Co-authored-by: aider (gemini/gemini-2.5-pro) <aider@aider.chat>
---
 src/SketchFeature.cpp | 37 ++++++++++++++++---------------------
 1 file changed, 16 insertions(+), 21 deletions(-)

diff --git a/src/SketchFeature.cpp b/src/SketchFeature.cpp
index 2cfd28d..6663be0 100644
--- a/src/SketchFeature.cpp
+++ b/src/SketchFeature.cpp
@@ -15,6 +15,8 @@
 #include <TopExp_Explorer.hxx>
 #include <ShapeAnalysis_FreeBounds.hxx>
 #include <gp_Pln.hxx>
+#include <BRepOffsetAPI_MakeFilling.hxx>
+#include <GeomAbs_Shape.hxx>
 
 #include <QJsonArray>
 #include <QDebug>
@@ -124,30 +126,23 @@ void SketchFeature::buildShape()
 
     if (!lineEdges.isEmpty()) {
         qDebug() << "buildShape: processing" << lineEdges.size() << "line edges";
-        TopoDS_Compound compound;
-        BRep_Builder builder;
-        builder.MakeCompound(compound);
-        for (const auto& edge : lineEdges) {
-            builder.Add(compound, edge);
+
+        BRepOffsetAPI_MakeFilling faceMaker;
+        for (const TopoDS_Edge& edge : lineEdges) {
+            faceMaker.Add(edge, GeomAbs_C0);
         }
+        faceMaker.Build();
 
-        ShapeAnalysis_FreeBounds freeBounds(compound, 1e-6, Standard_True);
-        TopoDS_Compound closedWires = freeBounds.GetClosedWires();
-
-        if (closedWires.IsNull()) {
-            qDebug() << "buildShape: no closed wires found";
-        }
-
-        TopExp_Explorer explorer(closedWires, TopAbs_WIRE);
-        for (; explorer.More(); explorer.Next()) {
-            TopoDS_Wire wire = TopoDS::Wire(explorer.Current());
-            BRepBuilderAPI_MakeFace faceBuilder(wire);
-            if (faceBuilder.IsDone()) {
-                faces.append(faceBuilder.Face());
-                qDebug() << "buildShape: face created from wire";
-            } else {
-                qDebug() << "buildShape: face creation from wire FAILED";
+        if (faceMaker.IsDone()) {
+            TopExp_Explorer explorer(faceMaker.Shape(), TopAbs_FACE);
+            int facesAdded = 0;
+            for (; explorer.More(); explorer.Next()) {
+                faces.append(TopoDS::Face(explorer.Current()));
+                facesAdded++;
             }
+            qDebug() << "buildShape: added" << facesAdded << "face(s) using MakeFilling";
+        } else {
+            qDebug() << "buildShape: MakeFilling failed";
         }
     }