Age | Commit message (Collapse) | Author |
|
There needs to be a way for a meta module like rocket to take
ownership of pipes immediately upon instantiation. Since the
pipes are created on demand as they become tapped by the modules
using htem, the simplest way to do this is to register some
callbacks with the ability to intercept the pipe creation in
terms of ownership and driving tap control etc.
This commit forms a minimal implementation of that, with the
ability to have a single intercepter hooked into a given stream.
It's a first-come-first-served situation, but that should suffice
for now since the rocket meta module would be the entrypoint for
such constructions. It then calls into another module to produce
on the stream, after it'll already have its hooks registered.
There might be a need for stacking hooks to let multiple modules
control pipes. GNU Rocket for instance only deals with
floats/doubles, and doesn't make it particularly easy to work on
higher order concepts like say orbiting a vector around a point
spatially. It might make sense to allow compositing of editors
where there's rocket controlling the simple floats, and another
doing dimensional/spatial stuff, with separate stacked meta
modules accomodating those editors. But that's putting the cart
before the horse, let's do the stupid simple thing for now and
see what this is like.
|
|
The driving tap's owner and pipe's owner are decoupled. When
tearing down an owner from a stream, any pipes its taps are
driving should also just go away. Otherwise its taps could
linger on pipes it doesn't own, which would be a UAF bug.
If the pipe is still needed, it'll just get recreated by another
tap. So there's a small perf hit, but this shouldn't be a
continuos kind of occurrence.
|
|
Some clarifications
|
|
|
|
When a driving tap becomes inactive, til_stream_tap() should be
able to notice and replace the driver.
An example driving tap becoming inactive would be a GNU Rocket
track that once had keys in it, but then had them all deleted.
This should set the inactive flag so the tap's automation can
take over. This gives the user at the Rocket editor the ability
to both take over from the tap automation and surrender control
back, by populating vs. emptying the respective track.
|
|
In order to implement something like a rocket module there needs
to be a way to iterate the pipes in the stream, and take
owernship of them when not already owned by rocket.
The way rocket's API works is you lookup tracks by name at
runtime. The rocket module will be a meta module that calls into
another module for rendering, arbitrarily configured via a rocket
setting a la checkers::fill_module.
So it won't be until the underlying modules do some rendering
that their taps get their respective pipes established in the
stream. Then the rocket module can look at all the pipes and for
any it doesn't own yet, it can get the tracks for those names and
take ownership while stowing the track handle in owner_foo for
the pipe.
While iterating all the pipes, the pipes already owned will have
the tracks readily available which can produce the values to
stick in the tap.
Something like that anyways, the til_stream_t api changes in this
commit are all preparatory for a rocket module.
|
|
Just clarify some verbiage, and actually assert type+n_elems
match. Note mismatch also fallsthrough to an -EINVAL just in
case asserts() have been compiled out (-DNDEBUG).
|
|
It seems likely that pipe owners will need not only a way to
differentiate themselves via the owner pointer, but also
somewhere to register a pipe-specific reference.
There probably needs to be a result pointer added for storing the
owner_foo when the owner taps, so the owner can make use of it.
|
|
Just some banal paperwork...
|
|
Until now there's just been a forward declared type for
til_fb_fragment_t.stream's type, and it's been completely unused.
The purpose of the stream is to provide a continous inter-frame
object where information can be stored pertaining to the stream
of frames.
Right now, that information is limited to emergent "pipes" formed
by using taps against a given stream. Taps at new paths in the
stream become added as pipes for those paths, with the
responsible tap hooked in as the driving tap. Taps at existing
paths become diverted to the driving taps, enabling potential for
external drivers for tapped variables.
This commit only adds the implementation, nothing is actually
using it yet.
|