When adjusting a slider, keyframe time, or curve value, it is undesirable to
re-cache the entire affected area while the user is still dragging UI objects.
Since the video is unlikely to be playing, the priority must go to the
currently active frame so the user gets visual feedback on the rendered image
as soon as possible. This was implemented in some areas, but this commit should
have that functionality in all areas.
Since rationals aren't a known Qt format, the QVariant container can't
automatically convert them to and from strings (for XML serialization). We have
to hijack these functions and do the conversion manually for those types.
Also moved the block name type to a node input, which means it's serialized
and copied by default (I'm not sure why it wasn't already like this).
This functions more or less identically to using a media out value, but the
desired speed is preserved through block length changes, even if the block's
length is reduced to zero (i.e. no rounding errors).
Previously the non-keyframed value was stored as a static keyframe but this
introduced issues when an input was in a state of keyframes being enabled but
0 keyframes existing. Having a standard value makes much more sense.
Since all NodeInputs will generally only need their data type and default
value set once, we place it all into the constructor for cleaner and easier
to manage code.
With differently set speeds, these functions would mess with the timing in ways
that would be confusing to the user. Now they act in a much more intuitive way
and also prevent negative media times.
Splitting commands would run CopyInputs after set_length. Since length is now
a parameter (aka a NodeInput) the former would override the latter breaking the
implementation. This commit fixes that.
Transitions are nodes but have a few parameters that are programmatic and always
required. This lets people write external code for transitions as well.
An earlier commit implementing media in and out parameters was primarily for
this addition. A simple control dialog for the clip's speed presentation
reimplemented from the old codebase.
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
Like the base "Block" type, the "Transition" type will not be a node used on its
own, it will have to be derived. This type defines some basic behavior for a
transition (e.g. how much it overlaps its "from" and "to" blocks).
Since all Nodes have an output that provides all output values now, we now
never need to add an output from a Node derivative. These changes remove the
last of them and disable the ability to add more outputs from a derivative.
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).
Since the nodes won't be holding any rendering data themselves in this system,
we may as well enforce some level of non-write access by setting all the
functions to const. They were already const-friendly, they just weren't
labelled as such.
Fixes recurring design issue that the Blocks were a frequent exception to the
DAG concept. The Blocks connecting to each others inputs/outputs while not
necessarily being "dependent" on each other to produce an image continually
causes issues while trying to create a rendering code path. This redesign
should provide a more "directed" approach to the directed acyclic graph.
It was becoming inevitable to get rid of this, it was continuously an exception
that had to be made to the DAG concept seeing as blocks are never really
"dependents" on each other, i.e. the images they produce have nothing to do
with other blocks. The only exception is a transition which will also be
easier to accomplish with this slightly different design.
A signal emitted and received in the same thread will call other functions
before returning to the one that emitted the signal. If these other functions
try to lock a mutex while a mutex is already locked by the emitting function,
we get stuck in a deadlock. These changes ensure that a signal is never emitted
by any function until all the nodes locked by it are unlocked.
Previous iterations would use mutexes to prevent changing of the graph
mid-render, however several user actions would need to capture these mutexes
causing the main thread to hang until the current render job (frame/range of
samples) was complete. We now copy the nodes necessary as part of the "compile"
process so that the main thread shouldn't need nearly as much blocking while
caching occurs.
itsmattkc