cmake+imgui: add imgui submodule

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "external/microprofile/microprofile"]
 	path = external/microprofile/microprofile
 	url = https://github.com/jonasmr/microprofile.git
+[submodule "imgui"]
+	path = external/imgui/imgui
+	url = https://github.com/ocornut/imgui.git

cmake_options.cmake

@@ -6,6 +6,7 @@ option(BUILD_VIEWER "Build GUI data viewer")
 
 option(ENABLE_SCRIPT_DEBUG "Enable verbose script execution")
 option(ENABLE_PROFILING "Enable detailed profiling metrics")
+option(ENABLE_IMGUI "Enable imgui plugin")
 
 option(TEST_DATA "Enable tests that require game data")
 

external/CMakeLists.txt

@@ -1,3 +1,7 @@
 if(ENABLE_PROFILING)
   add_subdirectory(microprofile)
 endif()
+
+if(ENABLE_IMGUI)
+  add_subdirectory(imgui)
+endif()

external/imgui/CMakeLists.txt

@@ -0,0 +1,58 @@
+add_library(imgui EXCLUDE_FROM_ALL
+    rw_imconfig.h
+    imgui/imgui.h
+    imgui/imgui.cpp
+    imgui/imgui_demo.cpp
+    imgui/imgui_draw.cpp
+    imgui/imgui_internal.h
+    imgui/imgui_widgets.cpp
+    imgui/imstb_rectpack.h
+    imgui/imstb_textedit.h
+    imgui/imstb_truetype.h
+)
+
+target_include_directories(imgui SYSTEM
+    PUBLIC
+        "${CMAKE_CURRENT_LIST_DIR}/imgui"
+)
+
+target_compile_definitions(imgui
+    PUBLIC
+        IMGUI_USER_CONFIG="${CMAKE_CURRENT_SOURCE_DIR}/rw_imconfig.h"
+)
+
+add_library(imgui::core ALIAS imgui)
+
+openrw_target_apply_options(
+    TARGET imgui
+)
+
+add_library(imgui_sdl_gl3 EXCLUDE_FROM_ALL
+    imgui/examples/imgui_impl_opengl3.h
+    imgui/examples/imgui_impl_opengl3.cpp
+    imgui/examples/imgui_impl_sdl.h
+    imgui/examples/imgui_impl_sdl.cpp
+)
+
+target_include_directories(imgui_sdl_gl3 SYSTEM
+    PUBLIC
+        "${CMAKE_CURRENT_LIST_DIR}/imgui/examples"
+)
+
+target_link_libraries(imgui_sdl_gl3
+    PUBLIC
+        imgui::core
+        SDL2::SDL2
+)
+
+# FIXME: extract gl loader to target + add property to get header
+target_compile_definitions(imgui_sdl_gl3
+    PRIVATE
+        "IMGUI_IMPL_OPENGL_LOADER_CUSTOM=\"${OpenRW_SOURCE_DIR}/rwcore/gl/gl_core_3_3.h\""
+)
+
+add_library(imgui::sdl_gl3 ALIAS imgui_sdl_gl3)
+
+openrw_target_apply_options(
+    TARGET imgui_sdl_gl3
+)

external/imgui/imgui

@@ -0,0 +1 @@
+Subproject commit 801645d35092c8da0eeabe71d7c1997c47aa3648

external/imgui/rw_imconfig.h

@@ -0,0 +1,9 @@
+#ifndef RW_IMCONFIG_H
+#define RW_IMCONFIG_H
+
+// Disable imgui assertions when not in debug mode
+#ifndef RW_DEBUG
+#define IM_ASSERT(MSG) //FIXME(madebr): remove comment
+#endif
+
+#endif // RW_IMCONFIG_H