Write ImGui config to an appropriate folder instead of the current one.

private/raid/application.cpp

@@ -6,7 +6,10 @@
 #include <fmt/base.h>
 #include <SDL3/SDL.h>
 #include <mijin/debug/assert.hpp>
+#include <mijin/platform/folders.hpp>
 #include <mijin/util/scope_guard.hpp>
+#include <mijin/virtual_filesystem/mapping.hpp>
+#include <mijin/virtual_filesystem/relative.hpp>
 #include <imgui.h>
 #include <backends/imgui_impl_opengl3.h>
 #include <backends/imgui_impl_sdl3.h>
@@ -27,6 +30,37 @@ int Application::run(int argc, char** argv)
     MIJIN_SCOPE_EXIT {
         cleanup();
     };
+
+    using namespace mijin::vfs_pipe;
+    mFS.addAdapter(os()
+        | relative_to(mijin::getKnownFolder(mijin::KnownFolder::USER_CONFIG_ROOT) / getFolderName())
+        | map_to("/config")
+    );
+    mFS.addAdapter(os()
+        | relative_to(mijin::getKnownFolder(mijin::KnownFolder::USER_DATA_ROOT) / getFolderName())
+        | map_to("/data")
+    );
+
+    auto createUserDir = [&](const fs::path& virtualPath)
+    {
+        mijin::Optional<fs::path> pathOpt = mFS.getNativePath(virtualPath);
+        if (!pathOpt.empty())
+        {
+            const fs::path path = std::move(*pathOpt);
+            if (!fs::exists(path))
+            {
+                const bool result = fs::create_directories(path);
+                MIJIN_ASSERT(result, "Error creating user folder.");
+            }
+        }
+        else
+        {
+            MIJIN_ERROR("User folder path shouldn't be empty.");
+        }
+    };
+    createUserDir("/config");
+    createUserDir("/data");
+
     if (!initSDL())
     {
         return ERR_INIT_FAILED;
@@ -50,12 +84,14 @@ int Application::run(int argc, char** argv)
             continue;
         }
 
+        ImGuiIO& imguiIO = ImGui::GetIO();
+
         ImGui_ImplOpenGL3_NewFrame();
         ImGui_ImplSDL3_NewFrame();
         ImGui::NewFrame();
 
         ImGui::SetNextWindowPos({0, 0});
-        ImGui::SetNextWindowSize(ImGui::GetIO().DisplaySize);
+        ImGui::SetNextWindowSize(imguiIO.DisplaySize);
 
         ImGui::Begin("##main", nullptr, ImGuiWindowFlags_NoBackground | ImGuiWindowFlags_NoDecoration);
         render();
@@ -68,6 +104,12 @@ int Application::run(int argc, char** argv)
         ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
 
         SDL_GL_SwapWindow(mWindow);
+
+        if (imguiIO.WantSaveIniSettings)
+        {
+            saveImGuiConfig();
+            imguiIO.WantSaveIniSettings = false;
+        }
     }
 
     return 0;
@@ -160,9 +202,12 @@ bool Application::initImGui()
         return false;
     }
 
+    loadImGuiConfig();
+
     ImGuiIO& imguiIO = ImGui::GetIO();
     imguiIO.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;
     imguiIO.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;
+    imguiIO.IniFilename = nullptr; // disable automatic saving of settings
 
     // default style
     ImGui::StyleColorsDark();
@@ -189,6 +234,8 @@ void Application::cleanup()
 {
     if (ImGui::GetCurrentContext() != nullptr)
     {
+        saveImGuiConfig();
+
         const ImGuiIO& imguiIO = ImGui::GetIO();
         if (imguiIO.BackendRendererUserData != nullptr)
         {
@@ -220,6 +267,40 @@ void Application::handleSDLEvents()
     }
 }
 
+void Application::loadImGuiConfig()
+{
+    std::unique_ptr<mijin::Stream> iniFile;
+    if (mFS.open("/config/imgui.ini", mijin::FileOpenMode::READ, iniFile) != mijin::StreamError::SUCCESS)
+    {
+        return;
+    }
+    std::string config;
+    if (iniFile->readAsString(config) != mijin::StreamError::SUCCESS)
+    {
+        msgWarning("IO error reading ImGui config.");
+        return;
+    }
+    ImGui::LoadIniSettingsFromMemory(config.c_str());
+}
+
+void Application::saveImGuiConfig()
+{
+    std::unique_ptr<mijin::Stream> iniFile;
+    if (const mijin::StreamError error = mFS.open("/config/imgui.ini", mijin::FileOpenMode::WRITE, iniFile);
+        error != mijin::StreamError::SUCCESS)
+    {
+        msgError("Error opening ImGui config file for writing: {}.", mijin::errorName(error));
+        return;
+    }
+
+    std::size_t length = 0;
+    const char* config = ImGui::SaveIniSettingsToMemory(&length);
+    if (const mijin::StreamError error = iniFile->writeText(config); error != mijin::StreamError::SUCCESS)
+    {
+        msgError("Error writing ImGui config: {}.", mijin::errorName(error));
+    }
+}
+
 void QuickApp::init(QuickAppOptions options)
 {
     MIJIN_ASSERT_FATAL(options.callbacks.render, "Missing render callback.");
@@ -231,6 +312,11 @@ void QuickApp::render()
     mOptions.callbacks.render();
 }
 
+std::string QuickApp::getFolderName()
+{
+    return mOptions.folderName;
+}
+
 int runQuick(int argc, char* argv[], QuickAppOptions options)
 {
     QuickApp app;

private/raid_test/main.cpp

@@ -8,6 +8,10 @@ namespace
 void render()
 {
     ImGui::Text("hi");
+
+    ImGui::Begin("Test");
+        ImGui::Text("Test Content");
+    ImGui::End();
 }
 }
 

public/raid/raid.hpp

@@ -7,6 +7,7 @@
 #include <cstdint>
 #include <functional>
 #include <fmt/format.h>
+#include <mijin/virtual_filesystem/stacked.hpp>
 #include <SDL3/SDL.h>
 
 namespace raid
@@ -33,6 +34,8 @@ private:
     SDL_Window* mWindow = nullptr;
     SDL_GLContext mGLContext = nullptr;
 
+    mijin::StackedFileSystemAdapter mFS;
+
     using glClear_fn_t = void (*)(std::uint32_t);
     using glClearColor_fn_t = void (*)(float, float, float, float);
 
@@ -46,6 +49,7 @@ public:
 
 protected:
     virtual void render() = 0;
+    virtual std::string getFolderName() = 0;
     virtual void handleMessage(const Message& message);
     virtual void handleSDLEvent(const SDL_Event& event);
 
@@ -106,6 +110,8 @@ private:
     bool initImGui();
     void cleanup();
     void handleSDLEvents();
+    void loadImGuiConfig();
+    void saveImGuiConfig();
 };
 
 using render_cb_t = std::function<void()>;
@@ -115,6 +121,7 @@ struct QuickAppOptions
     {
         render_cb_t render;
     } callbacks;
+    std::string folderName = "raid";
 };
 
 class QuickApp : public Application
@@ -124,6 +131,7 @@ private:
 public:
     void init(QuickAppOptions options);
     void render() override;
+    std::string getFolderName() override;
 };
 
 [[nodiscard]]