add lua navigation

main.cpp

@@ -9,12 +9,26 @@
 #include <RmlUi/Core.h>
 #include <RmlUi/Debugger.h>
 #include <RmlUi/Lua.h>
+#include <RmlUi/Lua/Interpreter.h>
 #include <RmlUi_Backend.h>
 #include <RmlUi_Include_Windows.h>
 #include <RmlUi_Include_GL3.h>
 #include <GLFW/glfw3.h>
 #include <png.h>
 
+extern "C" {
+#include <lua.h>
+#include <lauxlib.h>
+#include <lualib.h>
+}
+
+// Global app state for Lua access
+struct AppState {
+    Rml::Context* context = nullptr;
+    Rml::ElementDocument* document = nullptr;
+    std::filesystem::path assets_path;
+} g_app;
+
 void load_fonts(const std::filesystem::path& dir)
 {
     for (const auto& file : std::filesystem::directory_iterator(dir))
@@ -26,6 +40,57 @@ void load_fonts(const std::filesystem::path& dir)
     }
 }
 
+// Lua function: loadScreen(path) - loads a new RML document
+// Path is relative to assets folder
+int lua_loadScreen(lua_State* L)
+{
+    const char* path = luaL_checkstring(L, 1);
+
+    std::filesystem::path full_path = g_app.assets_path / path;
+
+    if (!std::filesystem::exists(full_path))
+    {
+        std::println("Screen not found: {}", full_path.string());
+        lua_pushboolean(L, false);
+        return 1;
+    }
+
+    // Unload current document
+    if (g_app.document)
+    {
+        g_app.context->UnloadDocument(g_app.document);
+        g_app.document = nullptr;
+    }
+
+    // Load new document
+    g_app.document = g_app.context->LoadDocument(full_path.string());
+    if (g_app.document)
+    {
+        g_app.document->Show();
+        std::println("Loaded screen: {}", path);
+        lua_pushboolean(L, true);
+    }
+    else
+    {
+        std::println("Failed to load screen: {}", path);
+        lua_pushboolean(L, false);
+    }
+
+    return 1;
+}
+
+// Register custom Lua functions
+void registerLuaFunctions()
+{
+    lua_State* L = Rml::Lua::Interpreter::GetLuaState();
+
+    // Register global function
+    lua_pushcfunction(L, lua_loadScreen);
+    lua_setglobal(L, "loadScreen");
+
+    std::println("Registered Lua functions");
+}
+
 void DumpElementTree(Rml::Element* element, std::ofstream& out, int depth = 0)
 {
     if (!element) return;
@@ -173,22 +238,25 @@ int main(const int argc, const char* argv[])
     Rml::Initialise();
     Rml::Lua::Initialise();
 
-    Rml::Context* context = Rml::CreateContext("main", Rml::Vector2i(window_width, window_height));
-    if (!context)
+    g_app.context = Rml::CreateContext("main", Rml::Vector2i(window_width, window_height));
+    if (!g_app.context)
     {
         Rml::Shutdown();
         Backend::Shutdown();
         return EXIT_FAILURE;
     }
 
+    // Register custom Lua functions
+    registerLuaFunctions();
+
     // Find the assets folder by checking for fonts
-    std::filesystem::path assets_path = std::filesystem::absolute(file.parent_path());
+    g_app.assets_path = std::filesystem::absolute(file.parent_path());
 
     // Walk up the directory tree to find a folder containing .ttf fonts
-    while (!assets_path.empty() && assets_path.has_parent_path())
+    while (!g_app.assets_path.empty() && g_app.assets_path.has_parent_path())
     {
         bool has_fonts = false;
-        for (const auto& entry : std::filesystem::directory_iterator(assets_path))
+        for (const auto& entry : std::filesystem::directory_iterator(g_app.assets_path))
         {
             if (entry.path().extension() == ".ttf")
             {
@@ -197,15 +265,15 @@ int main(const int argc, const char* argv[])
             }
         }
         if (has_fonts) break;
-        assets_path = assets_path.parent_path();
+        g_app.assets_path = g_app.assets_path.parent_path();
     }
 
-    load_fonts(assets_path);
+    load_fonts(g_app.assets_path);
 
-    Rml::ElementDocument* document = context->LoadDocument(file.string());
-    if (document)
+    g_app.document = g_app.context->LoadDocument(file.string());
+    if (g_app.document)
     {
-        document->Show();
+        g_app.document->Show();
     }
 
     // Dump mode: render and capture screenshot
@@ -222,10 +290,10 @@ int main(const int argc, const char* argv[])
         }
 
         // First render to default framebuffer to initialize everything
-        Backend::ProcessEvents(context);
-        context->Update();
+        Backend::ProcessEvents(g_app.context);
+        g_app.context->Update();
         Backend::BeginFrame();
-        context->Render();
+        g_app.context->Render();
         Backend::PresentFrame();
 
         // Create dump folder if it doesn't exist
@@ -238,7 +306,7 @@ int main(const int argc, const char* argv[])
         {
             dump_file << "Window: " << window_width << "x" << window_height << "\n";
             dump_file << "\n=== Element Layout ===\n";
-            DumpElementTree(document, dump_file);
+            DumpElementTree(g_app.document, dump_file);
             dump_file.close();
         }
 
@@ -252,8 +320,8 @@ int main(const int argc, const char* argv[])
         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
         // Render to FBO
-        context->Update();
-        context->Render();
+        g_app.context->Update();
+        g_app.context->Render();
 
         // Read pixels
         auto pixels = fbo.readPixels();
@@ -269,7 +337,7 @@ int main(const int argc, const char* argv[])
         return EXIT_SUCCESS;
     }
 
-    const HANDLE hNotif = FindFirstChangeNotification(assets_path.c_str(),
+    const HANDLE hNotif = FindFirstChangeNotification(g_app.assets_path.c_str(),
         TRUE, FILE_NOTIFY_CHANGE_LAST_WRITE);
 
     bool running = true;
@@ -278,22 +346,22 @@ int main(const int argc, const char* argv[])
         if (const DWORD wait_result = WaitForSingleObject(hNotif, 100);
             wait_result == WAIT_OBJECT_0)
         {
-            if (document)
-                context->UnloadDocument(document);
-            context->Update();
+            if (g_app.document)
+                g_app.context->UnloadDocument(g_app.document);
+            g_app.context->Update();
             std::this_thread::sleep_for(std::chrono::milliseconds(100));
-            document = context->LoadDocument(file.string());
-            if (document)
+            g_app.document = g_app.context->LoadDocument(file.string());
+            if (g_app.document)
             {
-                document->ReloadStyleSheet();
-                document->Show();
+                g_app.document->ReloadStyleSheet();
+                g_app.document->Show();
             }
             FindNextChangeNotification(hNotif);
         }
-        running = Backend::ProcessEvents(context);
-        context->Update();
+        running = Backend::ProcessEvents(g_app.context);
+        g_app.context->Update();
         Backend::BeginFrame();
-        context->Render();
+        g_app.context->Render();
         Backend::PresentFrame();
     }