The nodes now have more control over how their accelerated shaders/sample
functions are run, as well as how items are popped off the value tables.
This allows for various optimizations that we didn't have access to before.
Several things are accomplished in this commit, including:
- Use OIIO instead of our own functions for pixel format conversions
(cleaner code/less for us to maintain)
- Fold all PixelService functions into the PixelFormat class
(cleaner code)
- Moved OpenGL pixel definitions to OpenGL classes and out of the
global classes.
- Add support for RGB buffers as well as RGBA (optimization)
functions
Indexing is a lengthy process and had a high chance of getting RenderWorkers
stuck doing it rather than being responsive to cache requests. This commit
introduces a system where workers never index media, but instead signal that
media is not ready to their RenderBackends which ensure that the media gets
indexed and re-queues the affected frames when those indexes are ready.