Missing RenderSystem APIs

[KungFooMasta]

This is sort of a papercut, although I'm not sure of a solution either.

The RenderSystem has the following APIs:

_beingFrame
_endFrame
_pauseFrame
_resumeFrame

However I couldn't find any APIs that told me if the frame has begun or not. I'm writing a small class I want to share with others, which uses the RenderSystem, however in my code I can't tell if I need to call _beginFrame, it really depends if the frame has not been started. Accidentally calling _beginFrame at the wrong time will cause a crash, so its not easy to implement a workaround for this. (Think of rendering to a Texture, which likely hasn't started rendering a frame, vs a RenderWindow, which may or may not have started rendering a frame at any given time)

I propose we add something like

_frameStarted

I made a post in the help section, in case there is a solution that I can use: http://www.ogre3d.org/forums/viewtopic. ... 05&start=0