Move to imgui submodules

.gitmodules

@@ -6,3 +6,10 @@
 [submodule "data/doxygen-awesome-css"]
 	path = data/doxygen-awesome-css
 	url = https://github.com/jothepro/doxygen-awesome-css
+[submodule "src/frontend/gui/vendor/imgui"]
+	path = src/frontend/gui/vendor/imgui
+	url = https://github.com/apache-hb/imgui
+	branch = docking
+[submodule "src/frontend/gui/vendor/implot"]
+	path = src/frontend/gui/vendor/implot
+	url = https://github.com/epezent/implot

src/frontend/gui/editor/src/main.cpp

@@ -1103,7 +1103,7 @@ int main(int argc, const char **argv)
 
     while (draw::begin_frame())
     {
-        ImGui::DockSpaceOverViewport(ImGui::GetMainViewport());
+        ImGui::DockSpaceOverViewport();
         DrawMainMenuBar("Cthulhu");
         DrawEditorWidgets();
         draw::end_frame();

src/frontend/gui/editor/src/stdafx.hpp

@@ -17,7 +17,7 @@
 // dear imgui + widgets
 #include "imgui.h"
 #include "imgui_internal.h"
-#include "imgui_stdlib.h"
+#include "imgui/misc/cpp/imgui_stdlib.h"
 #include "implot.h"
 #include "imfilebrowser.h"
 #include "imgui_memory_editor.h"

src/frontend/gui/vendor/ctuconfig.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include "base/panic.h"
+
+#define IM_ASSERT(EXPR) CTASSERT(EXPR)
+
+#if CTU_PARANOID
+#   define IMGUI_DEBUG_PARANOID
+#endif
+
+#if CTU_STB_SPRINTF
+#   define IMGUI_USE_STB_SPRINTF
+#   define IMGUI_DISABLE_STB_SPRINTF_IMPLEMENTATION
+#endif
+
+#define IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+#define IMGUI_DISABLE_OBSOLETE_KEYIO
+#define IMGUI_DEFINE_MATH_OPERATORS

src/frontend/gui/vendor/imfilebrowser/imfilebrowser.cpp

@@ -360,7 +360,7 @@ void ImGui::FileBrowser::Display()
             const bool selected = selectedFilenames_.find(rsc.name)
                                != selectedFilenames_.end();
             if(Selectable(rsc.showName.c_str(), selected,
-                          ImGuiSelectableFlags_DontClosePopups))
+                          ImGuiSelectableFlags_NoAutoClosePopups))
             {
                 const bool wantDir = flags_ & ImGuiFileBrowserFlags_SelectDirectory;
                 const bool canSelect = rsc.name != ".." && rsc.isDir == wantDir;