How to find out if a frame started

[KungFooMasta]

Hello,

I'm working on a 2D Renderer that uses Ogre, which I plan to release to the community, however there is just one last thing I couldn't figure out.

As I understand it, the RenderSystem performs render operations to render targets. In order to setup the render system for rendering, the _beginFrame and _endFrame APIs are called. My question is, is there a way to tell if the render system is currently rendering a frame? (At a particular point in time, how to tell if _beginFrame has been called?)

The reason to know this is to make the library easier for users. The Renderer class I'm making can be used at any time, however it can be called during frame rendering, or before/after frame rendering, and theres is a slight change in render system configuration for these cases.

[Kojack]

There's nothing I can find in the render systems or scene manager that would indicate it's between the begin and end frame. Mostly both of those methods just directly call the underlying graphics api, so maybe directx or opengl has something. Although the dx11 renderer actually does nothing when _beginFrame or _endFrame are called, they are empty (except an exception). (freaky, directx11 doesn't use beginscene?)

You might be able to roughly work it out by using a render queue listener. Between the _beginFrame and _endFrame the closest listener events are firePreRenderQueues and firePostRenderQueues. There's not much code between them and the frame methods, and none of it looks user accessible. So those should be roughly similar, just set a bool on and off in the listener.