From df984e9b59dc0428b9f1d3ae5bbc55229bfe8755 Mon Sep 17 00:00:00 2001
From: Tim Ohliger <ohliger.tim@gmail.com>
Date: Sat, 31 Aug 2024 19:36:41 +0200
Subject: [PATCH 1/2] Changed lookat, up, front, and zoom to optional args.

This is in line with the cpp implementation and avoids named args before
positional args.
---
 .../visualization/utility/DrawGeometry.cpp     |  2 +-
 cpp/pybind/visualization/utility.cpp           | 18 ++++++++++++------
 2 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/cpp/open3d/visualization/utility/DrawGeometry.cpp b/cpp/open3d/visualization/utility/DrawGeometry.cpp
index e057e393f29..858cd514d61 100644
--- a/cpp/open3d/visualization/utility/DrawGeometry.cpp
+++ b/cpp/open3d/visualization/utility/DrawGeometry.cpp
@@ -35,7 +35,7 @@ bool DrawGeometries(const std::vector<std::shared_ptr<const geometry::Geometry>>
                     Eigen::Vector3d *lookat /* = nullptr */,
                     Eigen::Vector3d *up /* = nullptr */,
                     Eigen::Vector3d *front /* = nullptr */,
-                    double *zoom /* = zoom */) {
+                    double *zoom /* = nullptr */) {
     Visualizer visualizer;
     if (!visualizer.CreateVisualizerWindow(window_name, width, height, left,
                                            top)) {
diff --git a/cpp/pybind/visualization/utility.cpp b/cpp/pybind/visualization/utility.cpp
index 77d63d5e100..70269ab36b1 100644
--- a/cpp/pybind/visualization/utility.cpp
+++ b/cpp/pybind/visualization/utility.cpp
@@ -133,22 +133,28 @@ void pybind_visualization_utility_definitions(py::module &m) {
                        &geometry_ptrs,
                const std::string &window_name, int width, int height, int left,
                int top, bool point_show_normal, bool mesh_show_wireframe,
-               bool mesh_show_back_face, Eigen::Vector3d lookat,
-               Eigen::Vector3d up, Eigen::Vector3d front, double zoom) {
+               bool mesh_show_back_face,
+               utility::optional<Eigen::Vector3d> lookat,
+               utility::optional<Eigen::Vector3d> up,
+               utility::optional<Eigen::Vector3d> front,
+               utility::optional<double> zoom) {
                 std::string current_dir =
                         utility::filesystem::GetWorkingDirectory();
                 DrawGeometries(geometry_ptrs, window_name, width, height, left,
                                top, point_show_normal, mesh_show_wireframe,
-                               mesh_show_back_face, &lookat, &up, &front,
-                               &zoom);
+                               mesh_show_back_face,
+                               lookat.has_value() ? &lookat.value() : nullptr,
+                               up.has_value() ? &up.value() : nullptr,
+                               front.has_value() ? &front.value() : nullptr,
+                               zoom.has_value() ? &zoom.value() : nullptr);
                 utility::filesystem::ChangeWorkingDirectory(current_dir);
             },
             "Function to draw a list of geometry::Geometry objects",
             "geometry_list"_a, "window_name"_a = "Open3D", "width"_a = 1920,
             "height"_a = 1080, "left"_a = 50, "top"_a = 50,
             "point_show_normal"_a = false, "mesh_show_wireframe"_a = false,
-            "mesh_show_back_face"_a = false, "lookat"_a, "up"_a, "front"_a,
-            "zoom"_a);
+            "mesh_show_back_face"_a = false, "lookat"_a = py::none(),
+            "up"_a = py::none(), "front"_a = py::none(), "zoom"_a = py::none());
     docstring::FunctionDocInject(m, "draw_geometries",
                                  map_shared_argument_docstrings);
 

From a0a3bcba09a2b6fe0a1b36a5975b6c9ac3c0ca9b Mon Sep 17 00:00:00 2001
From: Tim Ohliger <ohliger.tim@gmail.com>
Date: Mon, 16 Dec 2024 14:21:03 +0100
Subject: [PATCH 2/2] Removed overload since default args serve this case
 already

---
 cpp/pybind/visualization/utility.cpp | 19 -------------------
 1 file changed, 19 deletions(-)

diff --git a/cpp/pybind/visualization/utility.cpp b/cpp/pybind/visualization/utility.cpp
index 70269ab36b1..1e0cb09329f 100644
--- a/cpp/pybind/visualization/utility.cpp
+++ b/cpp/pybind/visualization/utility.cpp
@@ -108,25 +108,6 @@ void pybind_visualization_utility_definitions(py::module &m) {
                     {"up", "The up vector of the camera."},
                     {"front", "The front vector of the camera."},
                     {"zoom", "The zoom of the camera."}};
-    m.def(
-            "draw_geometries",
-            [](const std::vector<std::shared_ptr<const geometry::Geometry>>
-                       &geometry_ptrs,
-               const std::string &window_name, int width, int height, int left,
-               int top, bool point_show_normal, bool mesh_show_wireframe,
-               bool mesh_show_back_face) {
-                std::string current_dir =
-                        utility::filesystem::GetWorkingDirectory();
-                DrawGeometries(geometry_ptrs, window_name, width, height, left,
-                               top, point_show_normal, mesh_show_wireframe,
-                               mesh_show_back_face);
-                utility::filesystem::ChangeWorkingDirectory(current_dir);
-            },
-            "Function to draw a list of geometry::Geometry objects",
-            "geometry_list"_a, "window_name"_a = "Open3D", "width"_a = 1920,
-            "height"_a = 1080, "left"_a = 50, "top"_a = 50,
-            "point_show_normal"_a = false, "mesh_show_wireframe"_a = false,
-            "mesh_show_back_face"_a = false);
     m.def(
             "draw_geometries",
             [](const std::vector<std::shared_ptr<const geometry::Geometry>>