feat(gameclient): Introduce imgui framework

Core/CMakeLists.txt

@@ -24,6 +24,7 @@ target_link_libraries(corei_always INTERFACE
     corei_libraries_include
     resources
 )
+
 target_link_libraries(corei_always_no_pch INTERFACE
     core_config
     core_utility_no_pch

Core/Libraries/CMakeLists.txt

@@ -10,3 +10,8 @@ add_subdirectory(Source/debug)
 add_subdirectory(Source/EABrowserDispatch)
 add_subdirectory(Source/EABrowserEngine)
 add_subdirectory(Source/Compression)
+
+# Imgui library
+if (RTS_BUILD_OPTION_IMGUI)
+    add_subdirectory(Source/ImGui)
+endif ()

Core/Libraries/Source/ImGui/CMakeLists.txt

@@ -0,0 +1,57 @@
+FetchContent_Declare(
+    imgui
+    GIT_REPOSITORY https://github.com/ocornut/imgui.git
+    GIT_TAG 791ad9b82db44ada9fedb3e26b2d900974ac0959
+    SYSTEM
+)
+
+FetchContent_MakeAvailable(imgui)
+
+# Main IMGUI sources we are going to need
+set(IMGUI_BASE_SRCS
+    "${imgui_SOURCE_DIR}/imgui.cpp"
+    "${imgui_SOURCE_DIR}/imgui_draw.cpp"
+    "${imgui_SOURCE_DIR}/imgui_tables.cpp"
+    "${imgui_SOURCE_DIR}/imgui_widgets.cpp"
+    "${imgui_SOURCE_DIR}/imgui_demo.cpp"
+)
+
+# Main Win32 DX8 specific sources we are going to need we can specify more if we need extra platforms
+set(IMGUI_WIN32_DX8_ALL_SRCS
+    "${IMGUI_BASE_SRCS}"
+    "${imgui_SOURCE_DIR}/backends/imgui_impl_win32.cpp"
+    "${CMAKE_SOURCE_DIR}/Core/Libraries/Source/ImGui/dx8_backend/imgui_impl_dx8.cpp"
+)
+
+# All Include directories
+set(IMGUI_INCLUDE_DIRS
+    "${imgui_SOURCE_DIR}"
+    "${imgui_SOURCE_DIR}/backends"
+    # DX8 override. Remove the following once we are using a standard backend
+    "${CMAKE_SOURCE_DIR}/Core/Libraries/Source/ImGui/dx8_backend"
+)
+
+# start target build section
+# we currently have a hard dependency on dx8 and win32 api
+if (WIN32)
+    MESSAGE(STATUS "Enabling ImGui")
+
+    add_library(lib_imgui STATIC ${IMGUI_WIN32_DX8_ALL_SRCS}
+        "${CMAKE_CURRENT_LIST_DIR}/wrapper/ImGuiFrameManager.cpp"
+    )
+    target_include_directories(lib_imgui
+        PUBLIC ${IMGUI_INCLUDE_DIRS}
+        PUBLIC "${CMAKE_CURRENT_LIST_DIR}/wrapper")
+    target_link_libraries(lib_imgui PRIVATE d3d8lib)
+
+    # use our own imconfig.h
+    target_compile_definitions(lib_imgui
+        PRIVATE IMGUI_DISABLE_DEFAULT_IMCONFIG
+        PRIVATE IMGUI_USER_CONFIG="${CMAKE_CURRENT_LIST_DIR}/imconfig.h"
+        INTERFACE RTS_HAS_IMGUI
+    )
+else ()
+    # currently only WIN32 DX is supported
+    MESSAGE(FATAL_ERROR "Non-Windows platforms currently not supported for ImGui")
+endif ()
+# end target build section