The ImGui extension for axmol

#include "ImGui/ImGuiPresenter.h"
USING_NS_AX;
USING_NS_AX_EXT;

class GameScene : public Scene {
public:
    void onEnter() override
    {
        Scene::onEnter();
        ImGuiPresenter::getInstance()->addFont(R"(C:\Windows\Fonts\msyh.ttc)");
        /* For Simplified Chinese support, please use:
        ImGuiPresenter::getInstance()->addFont(R"(C:\Windows\Fonts\msyh.ttc)", ImGuiPresenter::DEFAULT_FONT_SIZE,
                                           ImGuiPresenter::CHS_GLYPH_RANGE::GENERAL);
        */
        ImGuiPresenter::getInstance()->enableDPIScale(); // enable dpi scale for 4K display support, depends at least one valid ttf/ttc font was added.
        ImGuiPresenter::getInstance()->addRenderLoop("#im01", AX_CALLBACK_0(GameScene::onImGuiDraw, this), this);
    }
    void onExit() override
    {
        Scene::onExit();
        ImGuiPresenter::getInstance()->removeRenderLoop("#im01");
    }
    void onImGuiDraw()
    {
        ImGui::Begin("window");
        ImGui::Text("FPS=%.1f", 1.f / ImGui::GetIO().DeltaTime);
        ImGui::End();
    }
}