Add 3mf export and import

src/CMakeLists.txt

@@ -123,6 +123,7 @@ if(NOT DEFINED MESHLAB_PLUGINS) # it may be already defined in parent directory
 	set(MESHLAB_PLUGINS
 		# IO plugins
 		meshlabplugins/io_3ds
+		meshlabplugins/io_3mf
 		meshlabplugins/io_base
 		meshlabplugins/io_bre
 		meshlabplugins/io_collada

src/external/CMakeLists.txt

@@ -55,6 +55,9 @@ if ((NOT MESHLAB_BUILD_MINI) AND MESHLAB_ALLOW_OPTIONAL_EXTERNAL_LIBRARIES)
 	# lib3ds - optional, for io_3ds
 	include(${CMAKE_CURRENT_SOURCE_DIR}/lib3ds.cmake)
 
+	# lib3mf - optional, for io_3mf
+	include(${CMAKE_CURRENT_SOURCE_DIR}/lib3mf.cmake)
+
 	# libigl - optional for filter_mesh_booleans
 	include(${CMAKE_CURRENT_SOURCE_DIR}/libigl.cmake)
 

src/external/lib3mf.cmake

@@ -0,0 +1,73 @@
+#############################################################################
+# MeshLab                                                           o o     #
+# A versatile mesh processing toolbox                             o     o   #
+#                                                                _   O  _   #
+# Copyright(C) 2023 - 2024                                         \/)\/    #
+# Visual Computing Lab                                            /\/|      #
+# ISTI - Italian National Research Council                           |      #
+#                                                                    \      #
+# All rights reserved.                                                      #
+#                                                                           #
+# This program is free software; you can redistribute it and/or modify      #
+# it under the terms of the GNU General Public License as published by      #
+# the Free Software Foundation; either version 2 of the License, or         #
+# (at your option) any later version.                                       #
+#                                                                           #
+# This program is distributed in the hope that it will be useful,           #
+# but WITHOUT ANY WARRANTY; without even the implied warranty of            #
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the             #
+# GNU General Public License (http://www.gnu.org/licenses/gpl.txt)          #
+# for more details.                                                         #
+#                                                                           #
+#############################################################################
+
+option(MESHLAB_ALLOW_DOWNLOAD_SOURCE_LIB3MF "Allow download and use of lib3MF source" ON)
+
+if(MESHLAB_ALLOW_DOWNLOAD_SOURCE_LIB3MF)
+  set(LIB3MF_DIR ${MESHLAB_EXTERNAL_DOWNLOAD_DIR}/lib3mf-2.3.2)
+  set(LIB3MF_CHECK ${LIB3MF_DIR}/CMakeLists.txt) 
+
+  if(NOT EXISTS ${LIB3MF_CHECK})
+    set(LIB3MF_LINK https://github.com/3MFConsortium/lib3mf/releases/download/v2.3.2/lib3mf-2.3.2-source-with-submodules.zip)
+    set(LIB3MF_MD5 e9f3f40de2bd58c3f9109d657c86f3a8)
+    download_and_unzip(
+      NAME "Lib3MF"
+      MD5  ${LIB3MF_MD5}
+      LINK ${LIB3MF_LINK}
+      DIR  ${MESHLAB_EXTERNAL_DOWNLOAD_DIR})
+    if(NOT download_and_unzip_SUCCESS)
+      message(STATUS "- Lib3MF - download failed")
+    endif()
+  endif()
+
+  if(EXISTS ${LIB3MF_CHECK})
+    message(STATUS "- Lib3MF - Using downloaded Lib3MF sources")
+    set(MESSAGE_QUIET ON)
+    set(LIB3MF_TESTS OFF)
+    add_subdirectory(${LIB3MF_DIR} EXCLUDE_FROM_ALL)
+
+    # Well, this is extremely ugly
+    # But due to some bug in lib3mf CMake function `generate_product_version`,
+    # it is not possible to build lib3mf with ninja on Windows, because the following
+    # error message will appear when processing VersionResource.rc
+    #
+    # fatal error RC1106: invalid option: -3
+    #
+    # I don't know what causes the bug. A workaround is to just simply exclude VersionResource.rc from the list
+    # of sources associated to the lib3mf target.
+    if( WIN32 AND CMAKE_GENERATOR STREQUAL "Ninja" )
+      get_target_property(LIB3MF_SRCS lib3mf SOURCES)
+      LIST(FILTER LIB3MF_SRCS EXCLUDE REGEX "VersionResource.rc")
+      SET_TARGET_PROPERTIES(lib3mf PROPERTIES SOURCES "${LIB3MF_SRCS}")
+    endif()
+    unset(MESSAGE_QUIET)
+  else()
+    message(FATAL " - Lib3MF - Could not add lib3mf to source tree ")
+  endif()
+
+  add_library(external-lib3mf INTERFACE)
+  target_link_libraries(external-lib3mf INTERFACE lib3mf)
+  target_include_directories(external-lib3mf INTERFACE ${LIB3MF_DIR}/Autogenerated/Bindings/Cpp)
+  install(TARGETS lib3mf DESTINATION ${MESHLAB_LIB_INSTALL_DIR})
+
+endif()

src/meshlabplugins/io_3mf/CMakeLists.txt

@@ -0,0 +1,34 @@
+#############################################################################
+# MeshLab                                                           o o     #
+# A versatile mesh processing toolbox                             o     o   #
+#                                                                _   O  _   #
+# Copyright(C) 2023 - 2024                                         \/)\/    #
+# Visual Computing Lab                                            /\/|      #
+# ISTI - Italian National Research Council                           |      #
+#                                                                    \      #
+# All rights reserved.                                                      #
+#                                                                           #
+# This program is free software; you can redistribute it and/or modify      #
+# it under the terms of the GNU General Public License as published by      #
+# the Free Software Foundation; either version 2 of the License, or         #
+# (at your option) any later version.                                       #
+#                                                                           #
+# This program is distributed in the hope that it will be useful,           #
+# but WITHOUT ANY WARRANTY; without even the implied warranty of            #
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the             #
+# GNU General Public License (http://www.gnu.org/licenses/gpl.txt)          #
+# for more details.                                                         #
+#                                                                           #
+#############################################################################
+
+set(HEADERS
+	io_3mf.h
+	)
+
+set(SOURCES
+	io_3mf.cpp
+	)
+
+add_meshlab_plugin(io_3mf ${SOURCES} ${HEADERS})
+
+target_link_libraries(io_3mf PUBLIC external-lib3mf)