Many thanks to Peter and Darian for clearing up my misunderstanding of
how vkResetCommandPool works. The manager creates command buffers from
the command pool on an as-needed basis (when the queue of available
buffers is empty), and keeps track of those buffers in a queue. When the
pool is reset, the queues (one each for primary and secondary command
buffers) are reset such that the tracked buffers are available again.
Imageless framebuffers would probably be easier and cleaner, but this
takes care of the validation error attempting to present the second
frame (because rendering was being done to the first frame's swapchain
image instead of the second frame's).
The new render system now passes validation for the first frame (but
no drawing is done by the various subsystems yet). Something is wrong
with how swap chain semaphores are handled thus the second frame fails.
Frame buffer attachments can now be defined externally, with
"$swapchain" supported for now (in which case, the swap chain defines
the size of the frame buffer).
Also, render pass render areas and pipeline viewport and scissor rects
are updated when necessary.
I don't like the current name (update_framebuffer), but if the
referenced render pass doesn't have a framebuffer, one is created. The
renderpass is referenced via the active renderpass of the named render
step. Unfortunately, this has uncovered a bug in the setup of renderpass
objects: main.deferred has output's renderpass, and main.deferred_cube
and output have bogus renderpass objects.
The creation of the render jobs doesn't really belong with the running
of those jobs. This makes the code a little easier to navigate as it was
too easy to lost between load-time and run-time code.
This is with the new render job scheme. I very much doubt it actually
works (can't start testing until everything passes, and it's disabled
for the moment (define in vid_render_vulkan.c)), but it's helping iron
out what more is needed in the render system.
Really, a bit more than stub as the basic code is there, but nothing
works properly yet due to missing resources (especially descriptor sets
and pools), and the frame buffer creation is still disabled.
The step dependencies are not handled yet as threading isn't used at
this stage, but since I'll require dependencies to always come earlier,
this shouldn't cause a problem.
The jobs will become the core of the renderer, with each job step being
one of a render pass, compute pass, or processor (CPU-only) task. The
steps support dependencies, which will allow for threading the system in
the future.
Currently, just the structures, parse support, and prototype job
specification (render.plist) have been implemented. No conversion to
working data is done yet, and many things, in particular resources, will
need to be reworked, but this gets the basic design in.
Render passes and subpasses are now mostly initialized, just command
buffers and frame buffer related info to go (including view/scissor for
pipelines).
Not only does this quieten the validation layers, it ensures that all
the object handles are named and where they need to be. Also fixes only
one pipeline being created instead of the 15 or so.
The render passes seem to be created successfully, but pipelines fail
due to not having layout set, resulting in a segfault (bug in validation
layers?).
.dictionary can ask for standard parsing via a .parse key (value is
ignored currently).
Fields can use $auto to use standard parsing for that field.
If either is used, the plist field descriptors are written.
They're currently just stubs, but this gets the render info loading
working without any errors. The next step is to connect up pipelines and
create the image resources, then implementing the task functions will
have meaning.
This gets an empty (no tasks or pipelines connected) render context
initialized and available for other subsystems to register their task
functions. Nothing is using it yet, but the test parse of rp_main_def
fails gracefully (needs those tasks).
This just sets up the memory block and cexpr descriptors for the
parameters, parameter parsing is separate (and next). The parameters are
aligned to their size.
There's still a lot of work to do, but the basics are in. The spec will
be parsed into info structs that can then be further processed to
generate all the actual structs, generally making things a little less
timing dependent (eg, image view info refers to its image by name).
The new render pass and subpass structs have their names mangled for now
until I can switch over to the new system.
While the old system did get things going, it felt clunky to set up,
especially when it came to variations on render passes (eg, flat vs
cube-mapped). Also, much of it felt inside-out, especially the
separation of pipelines and render passes: having to specify the render
pass and subpass in the pipeline spec made the spec feel overly coupled
to the render pass setup. While this is the case in Vulkan, it is not
reflected properly in the pipeline spec. The new system will adjust the
render pass and subpass parameters of the pipeline spec as needed,
making the pipeline specs more reusable, and hopefully less error prone
as the pipelines are directly referenced by the subpasses that use them.
In addition, subpass dependencies should be much easier to set up as
only the dependent subpass specifies the dependency and the subpass
source dependency is mentioned by name. Frame buffer attachments also
get a similar treatment.
The new spec "format" isn't quite finalized (needs to meet the enemy
known as parsing) but it feels like a good starting place.
