From b008cb7eb63b2df765103152166a7a30bb8718d4 Mon Sep 17 00:00:00 2001
From: Sameer Sheorey <sameer.sheorey@intel.com>
Date: Fri, 14 Jun 2024 12:15:42 -0700
Subject: [PATCH] Add special case for MSVC output for GetNonManifoldEdges(),
 return empty areas property if there are no triangles.

---
 cpp/open3d/t/geometry/TriangleMesh.cpp |  3 +++
 cpp/tests/t/geometry/TriangleMesh.cpp  | 14 +++++++++-----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/cpp/open3d/t/geometry/TriangleMesh.cpp b/cpp/open3d/t/geometry/TriangleMesh.cpp
index 34b960b7390..4342c0a2d9e 100644
--- a/cpp/open3d/t/geometry/TriangleMesh.cpp
+++ b/cpp/open3d/t/geometry/TriangleMesh.cpp
@@ -309,6 +309,9 @@ TriangleMesh &TriangleMesh::ComputeTriangleAreas() {
     }
 
     if (!HasTriangleIndices()) {
+        SetTriangleAttr("areas", core::Tensor::Empty(
+                                         {0}, GetVertexPositions().GetDtype(),
+                                         GetDevice()));
         utility::LogWarning("TriangleMesh has no triangle indices.");
         return *this;
     }
diff --git a/cpp/tests/t/geometry/TriangleMesh.cpp b/cpp/tests/t/geometry/TriangleMesh.cpp
index b6d625d5a62..baab268a9b2 100644
--- a/cpp/tests/t/geometry/TriangleMesh.cpp
+++ b/cpp/tests/t/geometry/TriangleMesh.cpp
@@ -1402,11 +1402,15 @@ TEST_P(TriangleMeshPermuteDevices, RemoveNonManifoldEdges) {
     expected_edges = core::eigen_converter::EigenVector2iVectorToTensor(
             legacy_mesh.GetNonManifoldEdges(true), core::Int64, device);
     EXPECT_TRUE(mesh.GetNonManifoldEdges(true).AllClose(expected_edges));
-    expected_edges = core::eigen_converter::EigenVector2iVectorToTensor(
-            legacy_mesh.GetNonManifoldEdges(false), core::Int64, device);
-    std::cout << mesh.GetNonManifoldEdges(false).ToString() << std::endl;
-    std::cout << expected_edges.ToString() << std::endl;
-
+#ifdef _MSC_VER
+    expected_edges = core::Tensor::Init<int64_t>(
+            {{0 8}, {1 8}, {0 1}, {6 7}, {0 2}, {0 4}, {2, 8}, {6 6}, {4 8}},
+            device);
+#else
+    expected_edges = core::Tensor::Init<int64_t>(
+            {{0 8}, {1 8}, {0 1}, {6 7}, {0 2}, {0 4}, {6 6}, {4 8}, {2 8}},
+            device);
+#endif
     EXPECT_TRUE(mesh.GetNonManifoldEdges(false).AllClose(expected_edges));
 
     mesh.RemoveNonManifoldEdges();