Enably QtForPython for Linux (#5667)

- Fix PALification and include Linux for the QtForPython gem
- Add Linux-only module loader for Pyside2 related modules
- Remove (unnecessary) #if !defined(Q_OS_WIN)

Signed-off-by: Steve Pham <82231385+spham-amzn@users.noreply.github.com>

Gems/QtForPython/Code/CMakeLists.txt

@@ -21,7 +21,8 @@ ly_add_target(
     NAME QtForPython.Editor.Static STATIC
     NAMESPACE Gem
     FILES_CMAKE
-        qtforpython_editor_${PAL_PLATFORM_NAME_LOWERCASE}_files.cmake
+        qtforpython_editor_files.cmake
+        ${CMAKE_CURRENT_SOURCE_DIR}/Source/Platform/${PAL_PLATFORM_NAME}/qtforpython_editor_${PAL_PLATFORM_NAME_LOWERCASE}_files.cmake
     PLATFORM_INCLUDE_FILES
         ${common_source_dir}/${PAL_TRAIT_COMPILER_ID}/qtforpython_${PAL_TRAIT_COMPILER_ID_LOWERCASE}.cmake
     INCLUDE_DIRECTORIES
@@ -45,6 +46,9 @@ ly_add_target(
     NAMESPACE Gem
     FILES_CMAKE
         qtforpython_shared_files.cmake
+    INCLUDE_DIRECTORIES
+        PRIVATE
+            ${CMAKE_CURRENT_SOURCE_DIR}/Source/Platform/${PAL_PLATFORM_NAME}
     BUILD_DEPENDENCIES
         PRIVATE
             Gem::QtForPython.Editor.Static

Gems/QtForPython/Code/Source/Platform/Linux/InitializeEmbeddedPyside2.h

@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) Contributors to the Open 3D Engine Project.
+ * For complete copyright and license terms please see the LICENSE at the root of this distribution.
+ *
+ * SPDX-License-Identifier: Apache-2.0 OR MIT
+ *
+ */
+#pragma once
+
+#include <AzCore/Debug/Trace.h>
+#include <dlfcn.h>
+
+namespace QtForPython
+{
+    const char* s_libPythonLibraryFile = "libpython3.7m.so.1.0";
+    const char* s_libPyside2LibraryFile = "libpyside2.abi3.so.5.14";
+    const char* s_libShibokenLibraryFile = "libshiboken2.abi3.so.5.14";
+
+    class InitializeEmbeddedPyside2
+    {
+    public:
+        InitializeEmbeddedPyside2()
+        {
+            m_libPythonLibraryFile = InitializeEmbeddedPyside2::LoadModule(s_libPythonLibraryFile);
+            m_libPyside2LibraryFile = InitializeEmbeddedPyside2::LoadModule(s_libPyside2LibraryFile);
+            m_libShibokenLibraryFile = InitializeEmbeddedPyside2::LoadModule(s_libShibokenLibraryFile);
+        }
+        virtual ~InitializeEmbeddedPyside2()
+        {
+            InitializeEmbeddedPyside2::UnloadModule(m_libShibokenLibraryFile);
+            InitializeEmbeddedPyside2::UnloadModule(m_libPyside2LibraryFile);
+            InitializeEmbeddedPyside2::UnloadModule(m_libPythonLibraryFile);
+        }
+
+    private:
+        static void* LoadModule(const char* moduleToLoad)
+        {
+            void* moduleHandle = dlopen(moduleToLoad, RTLD_NOW | RTLD_GLOBAL);
+            if (!moduleHandle)
+            {
+                const char* loadError = dlerror();
+                AZ_Error("QtForPython", false, "Unable to load python library %s for Pyside2: %s", moduleToLoad,
+                         loadError ? loadError : "Unknown Error");
+            }
+            return moduleHandle;
+        }
+
+        static void UnloadModule(void* moduleHandle)
+        {
+            if (moduleHandle)
+            {
+                dlclose(moduleHandle);
+            }
+        }
+
+        void* m_libPythonLibraryFile;
+        void* m_libPyside2LibraryFile;
+        void* m_libShibokenLibraryFile;
+    };
+} // namespace QtForPython

Gems/QtForPython/Code/Source/Platform/Linux/PAL_linux.cmake

@@ -6,4 +6,4 @@
 #
 #
 
-set(PAL_TRAIT_BUILD_QTFORPYTHON_SUPPORTED FALSE)
+set(PAL_TRAIT_BUILD_QTFORPYTHON_SUPPORTED TRUE)

Gems/QtForPython/Code/Source/Platform/Linux/qtforpython_editor_linux_files.cmake

@@ -0,0 +1,11 @@
+#
+# Copyright (c) Contributors to the Open 3D Engine Project.
+# For complete copyright and license terms please see the LICENSE at the root of this distribution.
+#
+# SPDX-License-Identifier: Apache-2.0 OR MIT
+#
+#
+
+set(FILES
+    InitializeEmbeddedPyside2.h
+)

Gems/QtForPython/Code/Source/Platform/Mac/InitializeEmbeddedPyside2.h

@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) Contributors to the Open 3D Engine Project.
+ * For complete copyright and license terms please see the LICENSE at the root of this distribution.
+ *
+ * SPDX-License-Identifier: Apache-2.0 OR MIT
+ *
+ */
+#pragma once
+
+namespace QtForPython
+{
+    class InitializeEmbeddedPyside2
+    {
+    public:
+        InitializeEmbeddedPyside2() = default;
+        virtual ~InitializeEmbeddedPyside2() = default;
+    };
+} // namespace QtForPython

Gems/QtForPython/Code/Source/Platform/Mac/qtforpython_editor_macos_files.cmake

@@ -0,0 +1,11 @@
+#
+# Copyright (c) Contributors to the Open 3D Engine Project.
+# For complete copyright and license terms please see the LICENSE at the root of this distribution.
+#
+# SPDX-License-Identifier: Apache-2.0 OR MIT
+#
+#
+
+set(FILES
+    InitializeEmbeddedPyside2.h
+)

Gems/QtForPython/Code/Source/Platform/Windows/InitializeEmbeddedPyside2.h

@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) Contributors to the Open 3D Engine Project.
+ * For complete copyright and license terms please see the LICENSE at the root of this distribution.
+ *
+ * SPDX-License-Identifier: Apache-2.0 OR MIT
+ *
+ */
+#pragma once
+
+namespace QtForPython
+{
+    class InitializeEmbeddedPyside2
+    {
+    public:
+        InitializeEmbeddedPyside2() = default;
+        virtual ~InitializeEmbeddedPyside2() = default;
+    };
+} // namespace QtForPython

Gems/QtForPython/Code/Source/Platform/Windows/qtforpython_editor_windows_files.cmake

@@ -0,0 +1,11 @@
+#
+# Copyright (c) Contributors to the Open 3D Engine Project.
+# For complete copyright and license terms please see the LICENSE at the root of this distribution.
+#
+# SPDX-License-Identifier: Apache-2.0 OR MIT
+#
+#
+
+set(FILES
+    InitializeEmbeddedPyside2.h
+)

Gems/QtForPython/Code/Source/QtForPythonModule.cpp

@@ -8,13 +8,17 @@
 
 #include <AzCore/Memory/SystemAllocator.h>
 #include <AzCore/Module/Module.h>
+#include <AzCore/Debug/Trace.h>
 
 #include <QtForPythonSystemComponent.h>
 
+#include "InitializeEmbeddedPyside2.h"
+
 namespace QtForPython
 {
     class QtForPythonModule
         : public AZ::Module
+        , private InitializeEmbeddedPyside2
     {
     public:
         AZ_RTTI(QtForPythonModule, "{81545CD5-79FA-47CE-96F2-1A9C5D59B4B9}", AZ::Module);
@@ -22,11 +26,13 @@ namespace QtForPython
 
         QtForPythonModule()
             : AZ::Module()
+            , InitializeEmbeddedPyside2()
         {
             m_descriptors.insert(m_descriptors.end(), {
                 QtForPythonSystemComponent::CreateDescriptor(),
             });
         }
+        ~QtForPythonModule() override = default;
 
         /**
          * Add required SystemComponents to the SystemEntity.

Gems/QtForPython/Code/Source/QtForPythonSystemComponent.cpp

@@ -203,10 +203,6 @@ namespace QtForPython
     {
         QtBootstrapParameters params;
        
-#if !defined(Q_OS_WIN)
-#error Unsupported OS platform for this QtForPython gem
-#endif
-
         params.m_mainWindowId = 0;
         using namespace AzToolsFramework;
         QWidget* activeWindow = nullptr;

cmake/3rdParty/Platform/Linux/BuiltInPackages_linux.cmake

@@ -45,3 +45,4 @@ ly_associate_package(PACKAGE_NAME squish-ccr-deb557d-rev1-linux
 ly_associate_package(PACKAGE_NAME astc-encoder-3.2-rev1-linux                       TARGETS astc-encoder                PACKAGE_HASH 2ba97a06474d609945f0ab4419af1f6bbffdd294ca6b869f5fcebec75c573c0f)
 ly_associate_package(PACKAGE_NAME ISPCTexComp-36b80aa-rev1-linux                    TARGETS ISPCTexComp                 PACKAGE_HASH 065fd12abe4247dde247330313763cf816c3375c221da030bdec35024947f259)
 ly_associate_package(PACKAGE_NAME lz4-1.9.3-vcpkg-rev4-linux                        TARGETS lz4                         PACKAGE_HASH 5de3dbd3e2a3537c6555d759b3c5bb98e5456cf85c74ff6d046f809b7087290d)
+ly_associate_package(PACKAGE_NAME pyside2-5.15.2-rev1-linux                         TARGETS pyside2                     PACKAGE_HASH ec04291f3940e76ac817bc0c825f7a47f18d8760f0bdb8da4530732f2a69405e)