libstage: add return value to stage_render_func_t

This introduces some stage_render() flow control and render-time
freeing of nodes via the nodes render_func().

It's particularly useful for one-shot ephemeral nodes which are
thrown on-screen and require nothing more than their render and
free funcs for a full lifecycle.  An example would be something
running an effect briefly which runs autonomously from just a
timer alone, returning the free request from the final render once
the ending time arrives.

0 files changed, 0 insertions, 0 deletions