Previously the OpenGL instance was tied to each render/cache task,
creating and destroying it each time one started and stopped. This was
completely unnecessary since the instance holds no state and can be
shared by all of the render tasks without having to expensively start
a new one.
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.
As opposed to simply leaving all values in the table, nodes can now "take"
values that they use to free up memory (e.g. "taking" input buffers if they're
used to produce an output buffer).
This is a fairly large change, expect regressions.
This mostly builds on the keyframing we already set up for video, but the
audio renderer will now appropriately updated keyframe inputs per sample in
accordance with keyframe values.
Creating and destroying textures is a slow process, particularly when we can
re-use them throughout most of the render chain. We now keep them stored so
they can be re-used which improves performance substantially.
This was many changes that were largely fundamentally related. They included:
- More const modifiers to enforce read only node graphs
- Support for fragment and vertex shaders from the nodes
- Support for node code loaded externally (embedded into the binary)
- Fixed issue preventing two textures from being used in a shader
- Removed several unused functions and cleaned up code
- Fixed video media node misreading its matrix input
If the nodes are now stateless, there's nothing stopping the renderer from
rendering multiple frames at once. Earlier since the nodes held some of their
input/output data (and that data could change per frame), it was not possible
to render multiple frames at once without conflicts. Now that the node state is
held in render threads, they can do whatever they want at any time.
If Nodes only have the one output, we don't need to do so much differentiation
between them. Previous iteration used outputs as like a distinct function
within a Node (e.g. length output would return one result, buffer output would
produce a different result - each run different code to produce their results).
Now in this iteration, it's more accurate to say a Node is just one function
(which seems more appropriate for a node system anyway).
Largely conforming renderers to new NodeValue system. Code seems a lot cleaner
this way which is a nice advantage. Likely non-functional as this won't
compile just yet and still needs probably another day or two of testing to get
it back to where it was before.
Major refactoring work to try sharing as much code as possible between the
video renderers and audio renderers, as well as make them as
platform-independent as possible.
commit
For testing the new iteration, the texture cache disk download was written
into the main thread instead of into the separate threads. Now they're back
in separate threads again.
Also I think some of these files probably should have been in the previous
commit.
Once again, conceptually this system should work, however it does not seem to
be the most efficient and it wouldn't surprise me if the multithreading was
eventually upgraded to an even more coherent system one day. However for
"core principles" this should be fairly decent.
itsmattkc