Mapple can be built with Qt6

applications/Mapple/CMakeLists.txt

@@ -4,12 +4,10 @@ get_filename_component(PROJECT_NAME ${CMAKE_CURRENT_LIST_DIR} NAME)
 project(${PROJECT_NAME})
 
 
-include(../../cmake/UseQt5.cmake)
-if (NOT QT5_FOUND)
-    message(WARNING "${PROJECT_NAME} requires Qt but Qt was not found. You can set 'Qt5_DIR' to the "
-            "directory containing 'Qt5Config.cmake' or 'qt5-config.cmake'. "
-            "Optionally, you can set the Qt5 root directory 'QT5_ROOT_PATH' to the directory "
-            "containing the 'bin' folder.")
+include(../../cmake/UseQt.cmake)
+if (NOT Qt6_FOUND AND NOT Qt5_FOUND)
+    message(WARNING "${PROJECT_NAME} requires Qt (Qt6 or Qt5), but Qt was not found. You can set 'Qt*_DIR' to the "
+            "directory containing 'Qt*Config.cmake' or 'qt*-config.cmake' (* is 5 or 6) to specify the location of Qt.")
     return()
 endif ()
 
@@ -212,7 +210,7 @@ if (MSVC)
     target_compile_definitions(${PROJECT_NAME} PRIVATE _CRT_SECURE_NO_DEPRECATE)
 endif ()
 
-target_link_libraries(${PROJECT_NAME} PRIVATE Qt5::Core Qt5::Gui Qt5::Widgets Qt5::OpenGL)
+target_link_libraries(${PROJECT_NAME} PRIVATE ${QtLibs})
 
 target_link_libraries(${PROJECT_NAME} PRIVATE easy3d::renderer easy3d::algo easy3d::gui)
 if (Easy3D_HAS_CGAL)

cmake/UseQt.cmake

@@ -0,0 +1,75 @@
+# *************************************************************************
+#      Copyright (C) 2015 Liangliang Nan <[email protected]>
+#      https://3d.bk.tudelft.nl/liangliang/
+#
+#      This file is part of Easy3D. If it is useful in your research/work,
+#      I would be grateful if you show your appreciation by citing it:
+#      ------------------------------------------------------------------
+#           Liangliang Nan.
+#           Easy3D: a lightweight, easy-to-use, and efficient C++ library
+#           for processing and rendering 3D data.
+#           Journal of Open Source Software, 6(64), 3255, 2021.
+#      ------------------------------------------------------------------
+#
+#      Easy3D is free software; you can redistribute it and/or modify
+#      it under the terms of the GNU General Public License Version 3
+#      as published by the Free Software Foundation.
+#
+#      Easy3D 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 for more details.
+#
+#      You should have received a copy of the GNU General Public License
+#      along with this program. If not, see <http://www.gnu.org/licenses/>.
+# *************************************************************************
+
+
+# ------------------------------------------------------------------------------
+# This file sets up Qt for CMake. When Qt6 was setup successfully, 'Qt6_FOUND'
+# will be set. If Qt6 is not found, it will try to find Qt5. If Qt5 is found,
+# 'Qt5_FOUND' will be set. If both Qt6 and Qt5 are not found, it will stop the
+# configuration and show an error message.
+# If either Qt6 or Qt5 is found, it will set QtLibs to the corresponding Qt
+# libraries, e.g., Qt5Core, Qt5Gui, Qt5Widgets, Qt5OpenGL, Qt5Xml, etc.
+#
+# To use Qt in your program, you only need to include this file and specifying
+# Qt libraries to link against, e.g.,
+#       ------------------------------------------------------------------------
+#           project(${PROJECT_NAME})
+#           include( ../cmake/UseQt.cmake )
+#           add_executable(${PROJECT_NAME}, main.cpp)
+#           target_link_libraries(${PROJECT_NAME} ${QtLibs})
+#       ------------------------------------------------------------------------
+# NOTE: 'UseQt.cmake' must be included after you define your project but before
+#       'add_executable()' or 'add_library()'.
+#
+#   The recommended way to specify libraries and headers with CMake is to use the
+#   target_link_libraries command. This command automatically adds appropriate
+#   include directories, compile definitions, the position-independent-code flag,
+#   and links to the qtmain.lib library on Windows.
+# ------------------------------------------------------------------------------
+
+# Find includes in corresponding build directories
+set(CMAKE_INCLUDE_CURRENT_DIR ON)
+# Instruct CMake to run moc automatically when needed.
+set(CMAKE_AUTOMOC ON)
+# Instruct CMake to run uic automatically when needed.
+set(CMAKE_AUTOUIC ON)
+# Instruct CMake to run rcc automatically when needed.
+set(CMAKE_AUTORCC ON)
+
+# This will find the Qt files.
+find_package(Qt6 COMPONENTS Core Widgets OpenGL OpenGLWidgets QUIET)
+if (Qt6_FOUND)
+    message(STATUS "Found Qt6 version: ${Qt6Core_VERSION}")
+    set(QtLibs Qt::Core Qt::Widgets Qt::OpenGL Qt::OpenGLWidgets)
+else()
+    find_package(Qt5 COMPONENTS Core Widgets OpenGL QUIET)
+    if (Qt5_FOUND)
+        message(STATUS "Found Qt5 version: ${Qt5Core_VERSION}")
+        set(QtLibs Qt5::Core Qt5::Widgets Qt5::OpenGL)
+    else()
+        message(FATAL_ERROR "Qt is required, either Qt6 or Qt5, but both cannot be found")
+    endif()
+endif()

easy3d/util/version.h

@@ -59,7 +59,7 @@ namespace easy3d {
 #define EASY3D_VERSION_NR 1020504
 
 /// Easy3D release date, in the format YYYYMMDD.
-#define EASY3D_RELEASE_DATE 20241129
+#define EASY3D_RELEASE_DATE 20241214
 
 
 #endif  // EASY3D_UTIL_VERSION_H

tutorials/Tutorial_204_Viewer_Qt/CMakeLists.txt

@@ -3,12 +3,10 @@ cmake_minimum_required(VERSION 3.12)
 get_filename_component(PROJECT_NAME ${CMAKE_CURRENT_SOURCE_DIR} NAME)
 project(${PROJECT_NAME})
 
-include(../../cmake/UseQt5.cmake)
-if (NOT QT5_FOUND)
-    message(WARNING "${PROJECT_NAME} requires Qt but Qt was not found. You can set 'Qt5_DIR' to the "
-            "directory containing 'Qt5Config.cmake' or 'qt5-config.cmake'. "
-            "Optionally, you can set the Qt5 root directory 'QT5_ROOT_PATH' to the directory "
-            "containing the 'bin' folder.")
+include(../../cmake/UseQt.cmake)
+if (NOT Qt6_FOUND AND NOT Qt5_FOUND)
+    message(WARNING "${PROJECT_NAME} requires Qt (Qt6 or Qt5), but Qt was not found. You can set 'Qt*_DIR' to the "
+            "directory containing 'Qt*Config.cmake' or 'qt*-config.cmake' (* is 5 or 6) to specify the location of Qt.")
     return()
 endif ()
 
@@ -83,5 +81,5 @@ endif ()
 target_compile_definitions(${PROJECT_NAME} PRIVATE "EXAMPLE_TITLE=\"${PROJECT_NAME}\"")
 
 target_include_directories(${PROJECT_NAME} PRIVATE ${Easy3D_INCLUDE_DIR})
-target_link_libraries(${PROJECT_NAME} PRIVATE Qt5::Core Qt5::Gui Qt5::Widgets Qt5::OpenGL easy3d::renderer)
+target_link_libraries(${PROJECT_NAME} PRIVATE ${QtLibs} easy3d::renderer)
 set_target_properties(${PROJECT_NAME} PROPERTIES FOLDER "tutorials")