Improve Qt handling in CMake

Support 3 options:

	* VIRCADIA_USE_SYSTEM_QT is set -- use system's Qt
	* VIRCADIA_QT_PATH is set -- use Qt found in that dir
	* Otherwise -- use downloaded Qt package

This removes these variables:
	* VIRCADIA_USE_QT_VERSION
	* VIRCADIA_USE_PREBUILT_QT
	* HIFI_QT_BASE

cmake/macros/SetupQt.cmake

@@ -25,6 +25,9 @@ function(calculate_qt5_version result _QT_DIR)
     set(_QT_CORE_DIR "${_QT_DIR}/lib/QtCore.framework/Versions/5/Headers")
   else()
     set(_QT_CORE_DIR "${_QT_DIR}/include/QtCore")
+    if(NOT EXISTS "${_QT_CORE_DIR}")
+      set(_QT_CORE_DIR "${_QT_DIR}/include/qt5/QtCore")
+    endif()
   endif()
   if(NOT EXISTS "${_QT_CORE_DIR}")
       message(FATAL_ERROR "Could not find 'include/QtCore' in '${_QT_DIR}'")
@@ -78,6 +81,17 @@ macro(setup_qt)
         message(FATAL_ERROR "Unable to locate Qt5CoreConfig.cmake in '${QT_CMAKE_PREFIX_PATH}'")
     endif()
 
+    set(RCC_BINARY "${QT_DIR}/bin/rcc")
+
+    if(NOT EXISTS "${RCC_BINARY}")
+    set(RCC_BINARY "${QT_DIR}/bin/rcc-qt5")
+    endif()
+
+    if(NOT EXISTS "${RCC_BINARY}")
+    message(FATAL_ERROR "Unable to locate rcc '${QT_DIR}'")
+    endif()
+
+
     message(STATUS "Using Qt build in : '${QT_DIR}' with version ${QT_VERSION}")
 
     # Instruct CMake to run moc automatically when needed.

hifi_qt.py

@@ -28,18 +28,83 @@ endif()
         self.args = args
         self.configFilePath = os.path.join(args.build_root, 'qt.cmake')
         self.version = os.getenv('VIRCADIA_USE_QT_VERSION', '5.15.2')
-
         self.assets_url = hifi_utils.readEnviromentVariableFromFile(args.build_root, 'EXTERNAL_BUILD_ASSETS')
 
-        defaultBasePath = os.path.expanduser('~/hifi/qt')
-        self.basePath = os.getenv('HIFI_QT_BASE', defaultBasePath)
-        if (not os.path.isdir(self.basePath)):
-            os.makedirs(self.basePath)
-        self.path = os.path.join(self.basePath, self.version)
-        self.fullPath = os.path.join(self.path, 'qt5-install')
-        self.cmakePath = os.path.join(self.fullPath, 'lib/cmake')
+        # OS dependent information
+        system = platform.system()
 
-        print("Using qt path {}".format(self.path))
+        qt_found = False
+
+        # Here we handle the 3 possible cases of dealing with Qt:
+        if os.getenv('VIRCADIA_USE_SYSTEM_QT'):
+            # 1. Using the system provided Qt. This is only recommended for Qt 5.15.0 and above,
+            # as it includes a required fix on Linux.
+            #
+            # This path only works on Linux as neither Windows nor OSX ship Qt.
+
+            if system != "Linux":
+                raise Exception("Using the system Qt is only supported on Linux")
+
+            cmake_paths = [ "lib64/cmake", "lib/cmake" ]
+            cmake_path_ok = False
+
+            # This makes the lockFile stuff happy. Needs to be writable.
+            self.path = tempfile.mkdtemp()
+
+            self.fullPath = '/usr'
+
+            # Find the cmake directory
+            for cp in cmake_paths:
+                self.cmakePath = os.path.join(self.fullPath, cp)
+                if os.path.isdir(self.cmakePath):
+                    cmake_path_ok = True
+                    break
+
+            if not cmake_path_ok:
+                raise Exception("Failed to find cmake directory. Looked under " + self.fullPath + " in " + (', '.join(cmake_paths)))
+
+            qt_found = True
+            print("Using system Qt")
+
+        elif os.getenv('VIRCADIA_QT_PATH'):
+            # 2. Using an user-provided directory.
+            # VIRCADIA_QT_PATH must point to a directory with a Qt install in it.
+
+            self.path = os.getenv('VIRCADIA_QT_PATH')
+            self.fullPath = self.path
+            self.cmakePath = os.path.join(self.fullPath, 'lib/cmake')
+
+            qt_found = True
+            print("Using Qt from " + self.fullPath)
+
+        else:
+            # 3. Using a pre-built Qt.
+            #
+            # This works somewhat differently from above, notice how path and fullPath are
+            # used differently in this case.
+            #
+            # In the case of an user-provided directory, we just use the user-supplied directory.
+            #
+            # For a pre-built qt, however, we have to unpack it. The archive is required to contain
+            # a qt5-install directory in it.
+
+            self.path = os.path.expanduser("~/vircadia-files/qt")
+            self.fullPath = os.path.join(self.path, 'qt5-install')
+            self.cmakePath = os.path.join(self.fullPath, 'lib/cmake')
+
+            if (not os.path.isdir(self.path)):
+                os.makedirs(self.path)
+
+            qt_found = os.path.isdir(self.fullPath)
+            print("Using a packaged Qt")
+
+        if qt_found:
+            # Sanity check, ensure we have a good cmake directory
+            if not os.path.isdir(os.path.join(self.cmakePath, "Qt5")):
+                raise Exception("Failed to find Qt5 directory under " + self.cmakePath)
+
+        # I'm not sure why this is needed. It's used by hifi_singleton.
+        # Perhaps it stops multiple build processes from interferring?
         lockDir, lockName = os.path.split(self.path)
         lockName += '.lock'
         if not os.path.isdir(lockDir):
@@ -47,21 +112,16 @@ endif()
 
         self.lockFile = os.path.join(lockDir, lockName)
 
-        if (os.getenv('VIRCADIA_USE_PREBUILT_QT')):
-            print("Using pre-built Qt5")
+        if qt_found:
+            print("Found pre-built Qt5")
             return
 
-        # OS dependent information
-        system = platform.system()
-        cpu_architecture = platform.machine()
-
         if 'Windows' == system:
             self.qtUrl = self.assets_url + '/dependencies/vcpkg/qt5-install-5.15.2-windows.tar.gz'
         elif 'Darwin' == system:
             self.qtUrl = self.assets_url + '/dependencies/vcpkg/qt5-install-5.15.2-macos.tar.gz'
         elif 'Linux' == system:
             import distro
-            dist = distro.linux_distribution()
 
             if 'x86_64' == cpu_architecture:
                 if distro.id() == 'ubuntu':
@@ -124,6 +184,14 @@ endif()
             print("Machine     : " + platform.machine())
             raise Exception('UNKNOWN OPERATING SYSTEM!!!')
 
+    def showQtBuildInfo(self):
+        print("")
+        print("It's also possible to build Qt for your distribution, please see the documentation at:")
+        print("https://github.com/vircadia/vircadia/tree/master/tools/qt-builder")
+        print("")
+        print("Alternatively, you can try building against the system Qt by setting the VIRCADIA_USE_SYSTEM_QT environment variable.")
+        print("You'll need to install the development packages, and to have Qt 5.15.0 or newer. ")
+
     def writeConfig(self):
         print("Writing cmake config to {}".format(self.configFilePath))
         # Write out the configuration for use by CMake

interface/CMakeLists.txt

@@ -34,14 +34,14 @@ if (ANDROID)
   add_custom_command(
     OUTPUT ${RESOURCES_RCC}
     DEPENDS ${RESOURCES_QRC} ${GENERATE_QRC_DEPENDS}
-    COMMAND "${QT_DIR}/bin/rcc"
+    COMMAND "${RCC_BINARY}"
     ARGS ${RESOURCES_QRC} -no-compress -binary -o ${RESOURCES_RCC}
   )
 else ()
   add_custom_command(
     OUTPUT ${RESOURCES_RCC}
     DEPENDS ${RESOURCES_QRC} ${GENERATE_QRC_DEPENDS}
-    COMMAND "${QT_DIR}/bin/rcc"
+    COMMAND "${RCC_BINARY}"
     ARGS ${RESOURCES_QRC} -binary -o ${RESOURCES_RCC}
   )
 endif()
@@ -199,6 +199,8 @@ endif()
 
 if (WIN32 OR APPLE)
   add_dependencies(${TARGET_NAME} resources)
+if (WIN32 OR APPLE OR UNIX)
+    add_dependencies(${TARGET_NAME} resources screenshare)
 endif()
 
 if (SCREENSHARE)
@@ -435,18 +437,20 @@ else()
   endif()
 endif()
 
-if (DEV_BUILD AND (APPLE OR UNIX))
-  # create a qt.conf file to override hard-coded search paths in Qt libs
-  set(QT_LIB_PATH "${QT_CMAKE_PREFIX_PATH}/../..")
-  if (APPLE)
-    set(QT_CONF_FILE "${RESOURCES_DEV_DIR}/../Resources/qt.conf")
-  else ()
-    set(QT_CONF_FILE "${INTERFACE_EXEC_DIR}/qt.conf")
-  endif ()
-  file(GENERATE
-    OUTPUT "${QT_CONF_FILE}"
-    CONTENT "[Paths]\nPrefix=${QT_LIB_PATH}\n"
-  )
+if (NOT $ENV{VIRCADIA_USE_SYSTEM_QT})
+  if (DEV_BUILD AND (APPLE OR UNIX))
+    # create a qt.conf file to override hard-coded search paths in Qt libs
+    set(QT_LIB_PATH "${QT_CMAKE_PREFIX_PATH}/../..")
+    if (APPLE)
+      set(QT_CONF_FILE "${RESOURCES_DEV_DIR}/../Resources/qt.conf")
+    else ()
+      set(QT_CONF_FILE "${INTERFACE_EXEC_DIR}/qt.conf")
+    endif ()
+    file(GENERATE
+      OUTPUT "${QT_CONF_FILE}"
+      CONTENT "[Paths]\nPrefix=${QT_LIB_PATH}\n"
+    )
+  endif()
 endif()
 
 if (SCRIPTS_INSTALL_DIR)

libraries/controllers/src/controllers/UserInputMapper.cpp

@@ -44,6 +44,10 @@
 #include "impl/Route.h"
 #include "impl/Mapping.h"
 
+#if QT_VERSION > QT_VERSION_CHECK(5, 13, 0)
+// FIXME: Remove this after Qt 5.15 upgrade
+#define endl Qt::endl
+#endif
 
 namespace controller {
     const uint16_t UserInputMapper::STANDARD_DEVICE = 0;

tools/nitpick/CMakeLists.txt

@@ -12,7 +12,7 @@ generate_qrc(OUTPUT ${RESOURCES_QRC} PATH ${CMAKE_CURRENT_SOURCE_DIR}/resources
 add_custom_command(
     OUTPUT ${RESOURCES_RCC}
     DEPENDS ${RESOURCES_QRC} ${GENERATE_QRC_DEPENDS}
-    COMMAND "${QT_DIR}/bin/rcc"
+    COMMAND "${RCC_BINARY}"
     ARGS ${RESOURCES_QRC} -binary -o ${RESOURCES_RCC}
 )
 

tools/skeleton-dump/src/SkeletonDumpApp.cpp

@@ -15,6 +15,11 @@
 #include <FBXSerializer.h>
 #include <AnimSkeleton.h>
 
+#if QT_VERSION > QT_VERSION_CHECK(5, 13, 0)
+// FIXME: Remove this after Qt 5.15 upgrade
+#define endl Qt::endl
+#endif
+
 SkeletonDumpApp::SkeletonDumpApp(int argc, char* argv[]) : QCoreApplication(argc, argv) {
 
     // parse command-line