Feature/dear imgui (#4987)

* Add imgui

* migrate render options

* remove wmcgui

* Add subsystem selection and highlighting

* Add a syntactic sugar extension for imgui

* don't rebuild the mission list every frame

* Add imgui_sugar extension

* Move helper functions out of lab_ui, add function to display consolidated table text for object

* add button to export cubemap

* fix entering and exiting the lab

* refactor some of this for greater cleanness

* use techroom lighting when no mission background is set

* minor things

* add imguizmo

* add imguizmo

* Add imgui

* migrate render options

* remove wmcgui

* Add subsystem selection and highlighting

* Add a syntactic sugar extension for imgui

* don't rebuild the mission list every frame

* Move helper functions out of lab_ui, add function to display consolidated table text for object

* add button to export cubemap

* fix entering and exiting the lab

* refactor some of this for greater cleanness

* minor things

* add imguizmo

* add imguizmo

* Add button to reset changes made in the render dialog

* refactoring

* unfuck rebase

* fix issue with loose mission files

* use with_CollapsingHeader for greater uniformity

* add weapon selection functionality

* make primaries and secondaries fire again

* implement animation triggers

* avoid crash when switching back and forth between ships with and without team colors

* add control to set team color setting to renderer texture dialog

* make sure the table text updates when the ship class changes

* let rotating subsystems rotate

* do not add imgui.h to pstypes

* code cleanup

* add subsys highlighter from fred

* Highlight non-modelled subsystems as well

* add cmdline flag to show the imgui demo dialogue

* fix compiler warnings reported by CI

* fix error when building the subsystem list

* refactor variable/method naming

* code cleanup

* remove vestigial code

* update to imgui 1.89.1

* add credits entry for imgui

* use the imgui namespace

* Separate the background dialog out into its own window

* make sure the subsystem highlights are placed correctly

Co-authored-by: Fabian Woltermann <fabian.woltermann@peakwork.com>

Author: The-E

.gitmodules

@@ -4,3 +4,4 @@
 [submodule "lib/libRocket"]
 	path = lib/libRocket
 	url = https://github.com/asarium/libRocket.git
+

code/CMakeLists.txt

@@ -70,6 +70,8 @@ target_link_libraries(code PUBLIC any)
 
 target_link_libraries(code PUBLIC optional)
 
+target_link_libraries(code PUBLIC imgui)
+
 # Headers for standalone "gui" on UNIX
 IF(UNIX)
 	TARGET_LINK_LIBRARIES(code PUBLIC ${MONGOOSE_LIBS})

code/cmdline/cmdline.cpp

@@ -260,6 +260,7 @@ Flag exe_params[] =
 	{ "-gr_debug",		"Output graphics debug information",			true,	0,									EASY_DEFAULT,					"Dev Tool",		"http://www.hard-light.net/wiki/index.php/Command-Line_Reference#-gr_debug", },
 	{ "-stdout_log",		"Output log file to stdout",				true,	0,									EASY_DEFAULT,					"Dev Tool",		"http://www.hard-light.net/wiki/index.php/Command-Line_Reference#-stdout_log", },
 	{ "-slow_frames_ok",	"Don't adjust timestamps for slow frames",	true,	0,									EASY_DEFAULT,					"Dev Tool",		"http://www.hard-light.net/wiki/index.php/Command-Line_Reference#-slow_frames_ok", },
+	{ "-imgui_debug",		"Show imgui debug/demo window in the lab",  true,	0,									EASY_DEFAULT,					"Dev Tool",		"http://www.hard-light.net/wiki/index.php/Command-Line_Reference#-imgui_debug", },	
 };
 // clang-format on
 
@@ -511,6 +512,7 @@ cmdline_parm slow_frames_ok_arg("-slow_frames_ok", nullptr, AT_NONE);	// Cmdline
 cmdline_parm fixed_seed_rand("-seed", nullptr, AT_INT);	// Cmdline_rng_seed,Cmdline_reuse_rng_seed;
 cmdline_parm luadev_arg("-luadev", nullptr, AT_NONE);	// Cmdline_lua_devmode
 cmdline_parm override_arg("-override_data", nullptr, AT_NONE);	// Cmdline_override_data
+cmdline_parm imgui_debug_arg("-imgui_debug", nullptr, AT_NONE);
 
 char *Cmdline_start_mission = NULL;
 int Cmdline_dis_collisions = 0;
@@ -545,6 +547,7 @@ bool Cmdline_log_to_stdout = false;
 bool Cmdline_slow_frames_ok = false;
 bool Cmdline_lua_devmode = false;
 bool Cmdline_override_data = false;
+bool Cmdline_show_imgui_debug = false;
 
 // Other
 cmdline_parm get_flags_arg(GET_FLAGS_STRING, "Output the launcher flags file", AT_STRING);
@@ -2176,6 +2179,10 @@ bool SetCmdlineParams()
 		Cmdline_override_data = true;
 	}
 
+	if (imgui_debug_arg.found()) {
+		Cmdline_show_imgui_debug = true;
+	}
+
 	if (show_video_info.found())
 	{
 		Cmdline_show_video_info = true;

code/cmdline/cmdline.h

@@ -155,6 +155,7 @@ extern bool Cmdline_log_to_stdout;
 extern bool Cmdline_slow_frames_ok;
 extern bool Cmdline_lua_devmode;
 extern bool Cmdline_override_data;
+extern bool Cmdline_show_imgui_debug;
 
 enum class WeaponSpewType { NONE = 0, STANDARD, ALL };
 extern WeaponSpewType Cmdline_spew_weapon_stats;

code/globalincs/pstypes.h

@@ -482,25 +482,37 @@ SCP_string dump_stacktrace();
 	const auto ptr_memset = std::memset;
 	#define memset memset_if_trivial_else_error
 
+// Forward declarations from libraries
+struct ImDrawListSplitter;
+
 // Put into std to be compatible with code that uses std::mem*
 namespace std
 {
-	template<typename T>
-	using trivial_check = std::is_trivially_copyable<T>;
+template <typename T>
+using trivial_check = std::is_trivially_copyable<T>;
+
+template <typename T>
+void* memset_if_trivial_else_error(
+	typename std::enable_if<!std::is_same<T, ImDrawListSplitter>::value, T>::type* memset_data,
+	int ch,
+	size_t count)
+{
+	static_assert(trivial_check<T>::value, "memset on non-trivial object");
+	return ptr_memset(memset_data, ch, count);
+}
 
-	template<typename T>
-	void *memset_if_trivial_else_error(T *memset_data, int ch, size_t count)
-	{
-		static_assert(trivial_check<T>::value, "memset on non-trivial object");
-		return ptr_memset(memset_data, ch, count);
-	}
+// assume memset on a void* is "safe"
+// only used in cutscene/mveplayer.cpp:mve_video_createbuf()
+inline void* memset_if_trivial_else_error(void* memset_data, int ch, size_t count)
+{
+	return ptr_memset(memset_data, ch, count);
+}
 
-	// assume memset on a void* is "safe"
-	// only used in cutscene/mveplayer.cpp:mve_video_createbuf()
-	inline void *memset_if_trivial_else_error(void *memset_data, int ch, size_t count)
-	{
-		return ptr_memset(memset_data, ch, count);
-	}
+// Dear ImGui triggers these as well, so we need to let them pass
+inline void* memset_if_trivial_else_error(ImDrawListSplitter* memset_data, int ch, size_t count)
+{
+	return ptr_memset(memset_data, ch, count);
+}
 
 	// MEMCPY!
 	const auto ptr_memcpy = std::memcpy;