Reorganize source files into logical subdirectories

Co-authored-by: Hirek193 <23196899+Hirek193@users.noreply.github.com>

rendering/renderer.cpp

@@ -0,0 +1,43 @@
+/*
+This Source Code Form is subject to the
+terms of the Mozilla Public License, v.
+2.0. If a copy of the MPL was not
+distributed with this file, You can
+obtain one at
+http://mozilla.org/MPL/2.0/.
+*/
+
+#include "stdafx.h"
+#include "renderer.h"
+#include "Logs.h"
+
+std::unique_ptr<gfx_renderer> GfxRenderer;
+
+bool gfx_renderer_factory::register_backend(const std::string &backend, gfx_renderer_factory::create_method func)
+{
+    backends[backend] = func;
+    return true;
+}
+
+std::unique_ptr<gfx_renderer> gfx_renderer_factory::create(const std::string &backend)
+{
+    auto it = backends.find(backend);
+    if (it != backends.end())
+        return it->second();
+
+    ErrorLog("renderer \"" + backend + "\" not found!");
+    return nullptr;
+}
+
+gfx_renderer_factory *gfx_renderer_factory::get_instance()
+{
+    if (!instance)
+        instance = new gfx_renderer_factory();
+
+    return instance;
+}
+
+gfx_renderer_factory *gfx_renderer_factory::instance;
+
+
+//---------------------------------------------------------------------------