wip: moving backend-related stuff out of the app logic

src/gui/backend/backend.hpp

@@ -0,0 +1,38 @@
+#ifndef CLRSYNC_BACKEND_HPP
+#define CLRSYNC_BACKEND_HPP
+
+#include <string>
+
+namespace clrsync::gui::backend{
+
+    struct window_config{
+        std::string title = "clrsync";
+        int width = 1280;
+        int height = 720;
+        bool resizable = true;
+        bool decorated = true;
+        bool transparent_framebuffer = true;
+        float clear_color[4] = {0.1f, 0.1f, 0.1f, 0.0f};
+    };
+    class backend_interface{
+    public:
+        virtual ~backend_interface() = default;
+
+        virtual bool initialize(const window_config& config) = 0;
+        virtual void shutdown() = 0;
+        virtual bool should_close() const = 0;
+        virtual void begin_frame() = 0;
+        virtual void end_frame() = 0;
+
+        virtual void* get_native_window() const = 0;
+        virtual void* get_graphics_context() const = 0;
+        
+        virtual bool init_imgui_backend() = 0;
+        virtual void shutdown_imgui_backend() = 0;
+        virtual void imgui_new_frame() = 0;
+        virtual void imgui_render_draw_data(void* draw_data) = 0;
+    };
+
+}
+
+#endif // CLRSYNC_BACKEND_HPP