1 files changed, 15 insertions, 13 deletions

diff --git a/scene/resources/mesh.cpp b/scene/resources/mesh.cpp
index 0b352efca..bb33962be 100644
--- a/scene/resources/mesh.cpp
+++ b/scene/resources/mesh.cpp
@@ -1123,27 +1123,29 @@ Error ArrayMesh::lightmap_unwrap(const Transform &p_base_transform, float p_texe
 
 		PoolVector<int> rindices = arrays[Mesh::ARRAY_INDEX];
 		int ic = rindices.size();
-		int index_ofs = indices.size();
 
 		if (ic == 0) {
-			indices.resize(index_ofs + vc);
-			face_materials.resize((index_ofs + vc) / 3);
-			for (int j = 0; j < vc; j++) {
-				indices[index_ofs + j] = vertex_ofs + j;
-			}
+
 			for (int j = 0; j < vc / 3; j++) {
-				face_materials[(index_ofs / 3) + j] = i;
+				if (Face3(r[j * 3 + 0], r[j * 3 + 1], r[j * 3 + 2]).is_degenerate())
+					continue;
+
+				indices.push_back(vertex_ofs + j * 3 + 0);
+				indices.push_back(vertex_ofs + j * 3 + 1);
+				indices.push_back(vertex_ofs + j * 3 + 2);
+				face_materials.push_back(i);
 			}
 
 		} else {
 			PoolVector<int>::Read ri = rindices.read();
-			indices.resize(index_ofs + ic);
-			face_materials.resize((index_ofs + ic) / 3);
-			for (int j = 0; j < ic; j++) {
-				indices[index_ofs + j] = vertex_ofs + ri[j];
-			}
+
 			for (int j = 0; j < ic / 3; j++) {
-				face_materials[(index_ofs / 3) + j] = i;
+				if (Face3(r[ri[j * 3 + 0]], r[ri[j * 3 + 1]], r[ri[j * 3 + 2]]).is_degenerate())
+					continue;
+				indices.push_back(vertex_ofs + ri[j * 3 + 0]);
+				indices.push_back(vertex_ofs + ri[j * 3 + 1]);
+				indices.push_back(vertex_ofs + ri[j * 3 + 2]);
+				face_materials.push_back(i);
 			}
 		}