update external dependencies and ExternalProject for compatibility with cmake 4.0

3rdparty/civetweb/civetweb.cmake

@@ -8,6 +8,7 @@ ExternalProject_Add(
     DOWNLOAD_DIR "${OPEN3D_THIRD_PARTY_DOWNLOAD_DIR}/civetweb"
     UPDATE_COMMAND ""
     CMAKE_ARGS
+        -DCMAKE_POLICY_VERSION_MINIMUM=3.5
         -DCIVETWEB_BUILD_TESTING=OFF
         -DCIVETWEB_ENABLE_CXX=ON
         -DCIVETWEB_SSL_OPENSSL_API_1_0=OFF

3rdparty/fmt/fmt.cmake

@@ -31,6 +31,7 @@ ExternalProject_Add(
         -DFMT_DOC=OFF
         -DFMT_TEST=OFF
         -DFMT_FUZZ=OFF
+        -DCMAKE_POLICY_VERSION_MINIMUM=3.5
     BUILD_BYPRODUCTS
         <INSTALL_DIR>/${Open3D_INSTALL_LIB_DIR}/${CMAKE_STATIC_LIBRARY_PREFIX}${FMT_LIB_NAME}${CMAKE_STATIC_LIBRARY_SUFFIX}
         <INSTALL_DIR>/${Open3D_INSTALL_LIB_DIR}/${CMAKE_STATIC_LIBRARY_PREFIX}${FMT_LIB_NAME}d${CMAKE_STATIC_LIBRARY_SUFFIX}

3rdparty/googletest/googletest.cmake

@@ -3,8 +3,8 @@ include(FetchContent)
 FetchContent_Declare(
     ext_googletest
     PREFIX googletest
-    URL https://github.com/google/googletest/archive/refs/tags/release-1.11.0.tar.gz
-    URL_HASH SHA256=b4870bf121ff7795ba20d20bcdd8627b8e088f2d1dab299a031c1034eddc93d5
+    URL https://github.com/google/googletest/releases/download/v1.16.0/googletest-1.16.0.tar.gz
+    URL_HASH SHA256=78c676fc63881529bf97bf9d45948d905a66833fbfa5318ea2cd7478cb98f399
     DOWNLOAD_DIR "${OPEN3D_THIRD_PARTY_DOWNLOAD_DIR}/googletest"
     UPDATE_COMMAND ""
     CONFIGURE_COMMAND ""

3rdparty/libjpeg-turbo/libjpeg-turbo.cmake

@@ -58,6 +58,7 @@ ExternalProject_Add(
     DOWNLOAD_DIR "${OPEN3D_THIRD_PARTY_DOWNLOAD_DIR}/libjpeg-turbo"
     UPDATE_COMMAND ""
     CMAKE_ARGS
+        -DCMAKE_POLICY_VERSION_MINIMUM=3.5
         -DCMAKE_INSTALL_PREFIX=<INSTALL_DIR>
         -DWITH_CRT_DLL=${WITH_CRT_DLL}
         -DENABLE_STATIC=ON

3rdparty/libpng/libpng.cmake

@@ -14,6 +14,7 @@ ExternalProject_Add(
     DOWNLOAD_DIR "${OPEN3D_THIRD_PARTY_DOWNLOAD_DIR}/libpng"
     UPDATE_COMMAND ""
     CMAKE_ARGS
+        -DCMAKE_POLICY_VERSION_MINIMUM=3.5
         -DCMAKE_INSTALL_PREFIX=<INSTALL_DIR>
         -DPNG_SHARED=OFF
         -DPNG_EXECUTABLES=OFF

3rdparty/librealsense/librealsense.cmake

@@ -21,6 +21,7 @@ ExternalProject_Add(
     COMMAND ${GIT_EXECUTABLE} apply --ignore-space-change --ignore-whitespace
         ${CMAKE_CURRENT_LIST_DIR}/fix-macos-arm64.patch
     CMAKE_ARGS
+        -DCMAKE_POLICY_VERSION_MINIMUM=3.5
         -DCMAKE_INSTALL_PREFIX=<INSTALL_DIR>
         -DBUILD_SHARED_LIBS=OFF
         -DBUILD_EXAMPLES=OFF

3rdparty/librealsense/libusb-CMakeLists.txt

@@ -1,7 +1,7 @@
 # ubuntu 12.04 LTS cmake version 2.8.7
 # ubuntu 14.04 LTS cmake version 2.8.12.2
 # ubuntu 16.04 LTS cmake version 3.5.1
-cmake_minimum_required(VERSION 2.8.3)
+cmake_minimum_required(VERSION 3.5)
 
 project(usb)
 

3rdparty/zeromq/zeromq_build.cmake

@@ -19,7 +19,7 @@ if(WIN32)
         string(APPEND lib_name -${CMAKE_VS_PLATFORM_TOOLSET})
     endif()
     string(APPEND lib_name -mt-s)
-    set(lib_suffix -4_3_3)
+    set(lib_suffix -4_3_5)
 else()
     set(WIN_CMAKE_ARGS "")
     set(lib_name zmq)
@@ -29,15 +29,16 @@ endif()
 ExternalProject_Add(
     ext_zeromq
     PREFIX zeromq
-    URL https://github.com/zeromq/libzmq/releases/download/v4.3.3/zeromq-4.3.3.tar.gz
-    URL_HASH SHA256=9d9285db37ae942ed0780c016da87060497877af45094ff9e1a1ca736e3875a2
+    URL https://github.com/zeromq/libzmq/releases/download/v4.3.5/zeromq-4.3.5.tar.gz
+    URL_HASH SHA256=6653ef5910f17954861fe72332e68b03ca6e4d9c7160eb3a8de5a5a913bfab43
     DOWNLOAD_DIR "${OPEN3D_THIRD_PARTY_DOWNLOAD_DIR}/zeromq"
     # do not update
     UPDATE_COMMAND ""
     CMAKE_ARGS
         # Does not seem to work. We have to directly set the flags on Windows.
         #-DCMAKE_POLICY_DEFAULT_CMP0091:STRING=NEW
         #-DCMAKE_MSVC_RUNTIME_LIBRARY:STRING=${CMAKE_MSVC_RUNTIME_LIBRARY}
+        -DCMAKE_POLICY_VERSION_MINIMUM=3.5
         -DBUILD_STATIC=ON
         -DBUILD_SHARED=OFF
         -DBUILD_TESTS=OFF
@@ -58,8 +59,8 @@ ExternalProject_Add(
 ExternalProject_Add(
     ext_cppzmq
     PREFIX zeromq
-    URL https://github.com/zeromq/cppzmq/archive/v4.7.1.tar.gz
-    URL_HASH SHA256=9853e0437d834cbed5d3c223bf1d755cadee70e7c964c6e42c4c6783dee5d02c
+    URL https://github.com/zeromq/cppzmq/archive/refs/tags/v4.10.0.tar.gz
+    URL_HASH SHA256=c81c81bba8a7644c84932225f018b5088743a22999c6d82a2b5f5cd1e6942b74
     DOWNLOAD_DIR "${OPEN3D_THIRD_PARTY_DOWNLOAD_DIR}/zeromq"
     UPDATE_COMMAND ""
     CONFIGURE_COMMAND ""

3rdparty/zlib/zlib.cmake

@@ -19,6 +19,7 @@ ExternalProject_Add(
     COMMAND       ${GIT_EXECUTABLE} apply --ignore-space-change --ignore-whitespace
                   ${CMAKE_CURRENT_LIST_DIR}/0001-patch-zlib-to-enable-unzip.patch
     CMAKE_ARGS
+        -DCMAKE_POLICY_VERSION_MINIMUM=3.5
         -DCMAKE_INSTALL_PREFIX=<INSTALL_DIR>
         # zlib needs visiible symbols for examples. Disabling example building causes
         # assember error in GPU CI. zlib symbols are hidden during linking.

util/ci_utils.sh

@@ -356,9 +356,7 @@ install_docs_dependencies() {
     command -v python
     python -V
     python -m pip install -U -q "pip==$PIP_VER"
-    # cmake 4.0 breaks librealsense. Remove restriction when librealsense is
-    # updated.
-    which cmake || python -m pip install -U -q "cmake<4.0"
+    which cmake || python -m pip install -U -q cmake
     python -m pip install -U -q -r "${OPEN3D_SOURCE_ROOT}/python/requirements_build.txt"
     if [[ -d "$1" ]]; then
         OPEN3D_ML_ROOT="$1"
@@ -378,6 +376,8 @@ install_docs_dependencies() {
 # Build documentation
 # Usage: build_docs $DEVELOPER_BUILD
 build_docs() {
+    echo "Using cmake: $(command -v cmake)"
+    cmake --version
     NPROC=$(nproc)
     echo NPROC="$NPROC"
     mkdir -p build