Id Software had pretty much nothing to do with the vulkan renderer (they
still get credit for code that's heavily based on the original quake
code, of course).
It's not used yet, and thus may have some incorrect settings, but I
decided that I will probably want it at some stage for qwaq. It's
essentially was was in the original spec, but updated for some of the
niceties added to parsing since I removed it back then. It's also in its
own file.
Despite the base IQM specification not supporting blend-shapes, I think
IQM will become the basis for QF's generic model representation (at
least for the more advanced renderers). After my experience with .mu
models (KSP) and unity mesh objects (both normal and skinned), and
reviewing the IQM spec, it looks like with the addition of support for
blend-shapes, IQM is actually pretty good.
This is just the preliminary work to get standard IQM models loading in
vulkan (seems to work, along with unloading), and they very basics into
the renderer (most likely not working: not tested yet). The rest of the
renderer seems to be unaffected, though, which is good.
The resource subsystem creates buffers, images, buffer views and image
views in a single batch operation, using a single memory object to back
all the buffers and images. I had been doing this by hand for a while,
but got tired of jumping through all those vulkan hoops. While it's
still a little tedious to set up the arrays for QFV_CreateResource (and
they need to be kept around for QFV_DestroyResource), it really eases
calculation of memory object size and sub-resource offsets. And
destroying all the objects is just one call to QFV_DestroyResource.
Vulkan doesn't appreciate the empty buffers that result from the model
not having any textures or surfaces that can be rendered (rightfully so,
for such a bare-metal api).
I doubt the calls were ever actually made in a normal map due to the
node actually being a node when breaking out of the loop, but when I
experimented with an empty world model (no nodes, one infinite empty
leaf) I found that visit_leaf was getting called twice instead of once.
Since it is updated every frame, it needs to be as fast as possible for
the cpu code. This seems to make a difference of about 10us (~130 ->
~120) when testing in marcher. Not a huge change, but the timing
calculation was wrapped around the entire base world pass, so there was
a fair bit of overhead from bsp traversal etc.
It makes a significant difference to level load times (approximately
halves them for demo1 and demo2). Nicely, it turns out I had implemented
the rest of the staging buffer code (in particular, flushing) correctly
in that it seems there's no corruption any of the data.
This is an extremely extensive patch as it hits every cvar, and every
usage of the cvars. Cvars no longer store the value they control,
instead, they use a cexpr value object to reference the value and
specify the value's type (currently, a null type is used for strings).
Non-string cvars are passed through cexpr, allowing expressions in the
cvars' settings. Also, cvars have returned to an enhanced version of the
original (id quake) registration scheme.
As a minor benefit, relevant code having direct access to the
cvar-controlled variables is probably a slight optimization as it
removed a pointer dereference, and the variables can be located for data
locality.
The static cvar descriptors are made private as an additional safety
layer, though there's nothing stopping external modification via
Cvar_FindVar (which is needed for adding listeners).
While not used yet (partly due to working out the design), cvars can
have a validation function.
Registering a cvar allows a primary listener (and its data) to be
specified: it will always be called first when the cvar is modified. The
combination of proper listeners and direct access to the controlled
variable greatly simplifies the more complex cvar interactions as much
less null checking is required, and there's no need for one cvar's
callback to call another's.
nq-x11 is known to work at least well enough for the demos. More testing
will come.
This allows for easy (and safe) printing of cexpr values where the type
supports it. Types that don't support printing would be due to being too
complex or possibly write-only (eg, password strings, when strings are
supported directly).
This allows a single render pass description to be used for both
on-screen and off-screen targets. While Vulkan does allow a VkRenderPass
to be used with any compatible frame buffer, and vkparse caches a
VkRenderPass created from the same description, this allows the same
description to be used for a compatible off-screen target without any
dependence on the swapchain. However, there is a problem in the caching
when it comes to targeting outputs with different formats.
As I had suspected, it's due to a synchronization problem between the
scrap and drawing. There's actually a double problem in that data
uploaded to the scrap isn't flushed until the first frame is rendered
causing a quick init-shutdown sequence to take at least five seconds due
to the staging buffer waiting (and timing out) on a stuck fence.
Rendering just one frame "fixes" the problem (draw was one of the
earliest subsystems to get going in vulkan).
Since it is updated every frame, it needs to be as fast as possible for
the cpu code. This seems to make a difference of about 10us (~130 ->
~120) when testing in marcher. Not a huge change, but the timing
calculation was wrapped around the entire base world pass, so there was
a fair bit of overhead from bsp traversal etc.
While looking at the deferred attachment images with using a template in
mind, I noticed that the opaque attachment was using 8-bit color. The
problem is, it's meant to be HDRI with the compose pass crunching it
down to LDRI. Switching to 16-bit float does seem to have made a subtle
difference (hey, it's still quake data, not much HDRI in there).
That certainly makes it nicer to work with large sets, and shows one way
to be careful with allocated resources: don't allocate them in the
inherited data and use a template that needs a few things filled in to
be valid. Also, it seems that overriding values in sub-structures "just
works" :)
It simply parses the referenced plist dictionary (via @inherit =
plist.path;) into the current data block, then allows the data to be
overwritten by the current plist dictionary. This may be a bit iffy for
any allocated resources, so some care must be taken, but it seems to
work nicely.
This allows a single render pass description to be used for both
on-screen and off-screen targets. While Vulkan does allow a VkRenderPass
to be used with any compatible frame buffer, and vkparse caches a
VkRenderPass created from the same description, this allows the same
description to be used for a compatible off-screen target without any
dependence on the swapchain. However, there is a problem in the caching
when it comes to targeting outputs with different formats.
This makes much more sense as they are intimately tied to the frame
buffer on which a render pass is working. Now, just the window width
and height are stored in vulkan_ctx_t. As a side benefit,
QFV_CreateSwapchain no long references viddef (now just palette and
conview in vulkan_draw.c to go).
While I have trouble imagining it making that much performance
difference going from 4 verts to 3 for a whopping 2 polygons, or even
from 2 triangles to 1 for each poly, using only indices for the vertices
does remove a lot of code, and better yet, some memory and buffer
allocations... always a good thing.
That said, I guess freeing up a GPU thread for something else could make
a difference.
I think I had gotten lucky with captures not being corrupt due to them
being much bigger than all but the L3 cache (and then they're over 1/2
the size), so the memory was being automatically invalidated by other
activity. Don't want to trust such luck, though.
It makes a significant difference to level load times (approximately
halves them for demo1 and demo2). Nicely, it turns out I had implemented
the rest of the staging buffer code (in particular, flushing) correctly
in that it seems there's no corruption any of the data.
This means that a tex_t object is passed in instead of just raw bytes
and width and height, but it means the texture can specify whether it's
flipped or uses BGR instead of RGB. This fixes the upside down
screenshots for vulkan.
Still work with gcc, of course, and I still need to fix them properly,
but now they're actually slightly easier to find as they all have vec_t
and FIXME on the same line.
Viewport and FOV updates are now separate so updating one doesn't cause
recalculations of the other. Also, perspective setup is now done
directly from the tangents of the half angles for fov_x and fov_y making
the renderers independent of fov/aspect mode. I imagine things are a bit
of a mess with view size changes, and especially screen size changes
(not supported yet anyway), and vulkan winds up updating its projection
matrices every frame, but everything that's expected to work does
(vulkan errors out for fisheye or warp due to frame buffer creation not
being supported yet).
r_screen isn't really the right place, but it gets the scene rendering
out of the low-level renderers and will make it easier to sort out
later, and hopefully easier to figure out a good design for vulkan.
The code is really part of scene (not a typo wrt r_screen: that is
misnamed as such, or at least SCR_UpdateScreen needs to be split into
screen (2d overlay, really) and scene updates).
This breaks fisheye rendering as the fisheye code calls the actual scene
render code multiple times, but the fisheye code is called by said scene
render code via a diversion. The fisheye needs to be moved out to the
high level scene render, but that will takes some extra work for frame
buffer setup.
This moves the common camera setup code out of the individual drivers,
and completely removes vup/vright/vpn from the non-software renderers.
This has highlighted the craziness around AngleVectors with it putting
+X forward, -Y right and +Z up. The main issue with this is it requires
a 90 degree pre-rotation about the Z axis to get the camera pointing in
the right direction, and that's for the native sw renderer (vulkan needs
a 90 degree pre-rotation about X, and gl and glsl need to invert an
axis, too), though at least it's just a matrix swizzle and vector
negation. However, it does mean the camera matrices can't be used
directly.
Also rename vpn to vfwd (still abbreviated, but fwd is much clearer in
meaning (to me, at least) than pn (plane normal, I guess, but which
way?)).
This is a step towards high-level unification of the renderers, as far
as possible keeping only actual low-level implementation details in the
individual renderers (some higher level stuff, eg shadows, is expected
to be per-renderer as some things are just not feasible to implement in
all renderers). However, the idea is to move the high-level
functionality into scene rendering.
While there's currently only the one still, this will allow the entities
to be multiply queued for multi-pass rendering (eg, shadows). As the
avoidance of putting an entity in the same queue more than once relies
on the entity id, all entities now come from the scene (which is stored
in cl_world in the client code for nq and qw), thus the extensive
changes in the clients.
While I doubt the difference is all that significant, this should speed
up entity rendering because it cuts out a lot of branching, and
eliminates scanning the same list multiple times only to not do anything
for large chunks of the list.
While both matrices had positive determinants in the first place, I find
the projection matrix easier to understand without all the negatives,
and having quake-x/vulkan-z positively parallel in the z-up matrix makes
that a lot easier to think about.
Regardless of whether the sky is spinning or not, the matrix needs to be
updated with the current origin in order to get the direction vector
right in the shader. Also, it's in the update that the required x-y
plane rotation gets in so the skies move in the correct direction.
