I am extending some functionality for the shortmath question type. I need to create a new separate page for providing some complex admin settings. This page is to be accessible via a link in the settings page.
The problem is that I want to use Mustache templates (rendered via PHP) for generating the page contents. So, for this to work I need a renderer class (ideally placed under classes/output). But since this plugin is a question type, I already have a specialized renderer extending qtype_renderer.
So, one option is to define the required render_something methods in the existing qtype_shortmath_renderer class. However, since this renderer is mainly meant for rendering questions, I feel like this might be the wrong approach? Alternatively, I could make an additional renderer class, extending plugin_renderer_base. But then calling $PAGE->get_renderer('type_shortmath') won't work properly with two renderers, so I would have to manually instantiate the renderer. However, I'm not sure of all the implications this would make.
So to sum up. What is the recommended way to generate page contents with Mustache templates, for a standalone page in a question type?