This is intended for the built-in 8x8 bitmap characters and quake's
"conchars", but could potentially be used for any simple (non-composed
characters) mono-spaced font. Currently, the buffers can be created,
destroyed, cleared, scrolled vertically in either direction, and
rendered to the screen in a single blast.
One of the reasons for creating the buffer is to make it so scaling can
be supported in the sw renderer.
While this does pull the grovelling for the subpic out to the callers,
the real problem is the excessive use of qpic_t in the internal code:
qpic_t is really just the image format in wad files, and shouldn't be
used as a generic image handle.
Cleans up more of the icky code in the font drawing functions.
This makes working with quads, implied alpha quads, and lines much
cleaner (and gets rid of the bulk of the "eww" fixme), and will probably
make it easier to support multiple scraps and fonts, and potentially
more flexible ordering between pipelines.
This means that QF should support more exotic fonts without any issue
(once the rest of the text handling system is up to snuff) as HarfBuzz
does all the hard work of handling OpenType, Graphite, etc text shaping,
including kerning (when enabled).
Also, font loading now loads all the glyphs into the atlas (preload is
gone).
It is currently an ugly hack for dealing with the separate quad queue,
and the pipeline handling code needs a lot of cleanup, but it works
quite well, though I do plan on moving to HarfBuzz for text shaping. One
nice development is I got updating of descriptor sets working (just need
to ensure the set is no longer in use by the command queue, which the
multiple frames in flight makes easy).
It's implemented only in the Vulkan renderer, partly because there's a
lot of experimenting going on with it, but the glyphs do get transferred
to the GPU (checked in render doc). No rendering is done yet: still
thinking about whether to do a quick-and-dirty test, or to add HarfBuzz
immediately, and the design surrounding that.
I have recently learned that pre-multiplied alpha is the correct way to
do compositing, which is pretty much what the 2d pass does (actually,
all passes, but...). This required ensuring the color factor passed to
the fragment shader is pre-multiplied (a little silly for cshifts as
they used to be pre-multiplied but were un-pre-multiplied early in QF's
history and I don't feel like fixing that right now as it affects all
renderers), and also pre-multiplying alpha when converting from 8-bit
palette to rgba as the palette entry for transparent has that funky pink
(which is used in full-brights).
The software renderer uses Bresenham's line slice algorithm as presented
by Michael Abrash in his Graphics Programming Black Book Special Edition
with the serial numbers filed off (as such, more just so *I* can read
the code easily), along with the Chen-Sutherland line clipping
algorithm. The other renderers were more or less trivial in comparison.
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.
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).
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).
They should increment by one for each pic, not 4 (I think some fluff
remaining from copying glsl's draw code).
I noticed the problem when I saw large gaps of 0s in the vertex data in
renderdoc.
This needed changing Vulkan_CreatePipeline to
Vulkan_CreateGraphicsPipeline for consistency (and parsing the
difference from a plist seemed... not worth thinking about).
This should fix the horrid frame rate dependent behavior of the view
model.
They are also in their own descriptor set so they can be easily shared
between pipelines. This has been verified to work for Draw.
Multiple render passes are needed for supporting shadow mapping, and
this is a huge step towards breaking the Vulkan render free of Quake,
and hopefully will lead the way for breaking the GL renderers free as
well.
The renderer's LineGraph now takes a height parameter, and netgraph now
uses cl_* cvars instead of r_* (which never really made sense),
including it's own height cvar (the render graphs still use
r_graphheight).
conwidth and conheight have been moved into vid.conview (probably change
the name at some time), and scr_vrect has been replaced by a view as
well. This makes it much easier to create 2d elements that follow the
screen size (taking advantage of a view's gravity) which will, in the
end, make changing the window size easier.
Not only does it makes sense to centralize the setting of viewport and
scissor, but it's actually necessary in order to fix the upside-down
rendering on windows.
After getting lights even vaguely working for alias models, I realized
that it just wasn't going to be feasible to do nice lighting with
forward rendering. This gets the bulk of the work done for deferred
rendering, but still need to sort out the shaders before any real
testing can be done.
Never really wanted in the first place (back when I did the plugin
renderers), but I didn't feel like doing the required work to avoid it
at the time. At least with Vulkan being a fresh start in an environment
that's already plugin-friendly, there was no real work involved. I'll
get to the other renderers eventually (especially now that I know gdb
does the right thing when there are multiple functions with the same
name).
It turns out I had conflated frame buffers with frames and wound up
making a minor mess when separating the number of frames the renderer
could have in flight from the number of swap-chain images. This is the
first step towards correcting that mistake.
It's not entirely there yet, but the basics are working. Work is still
needed for avoiding duplication of objects (different threads will have
different contexts and thus different tables, so necessary per-thread
duplication should not become a problem) and general access to arbitrary
fields (mostly just parsing the strings)
It now uses the ring buffer code I wrote for qwaq (and forgot about,
oops) to handle the packets themselves, and the logic for allocating and
freeing space from the buffer is a bit simpler and seems to be more
reliable. The automated test is a bit of a joke now, though, but coming
up with good tests for it... However, nq now cycles through the demos
without obvious issue under the same conditions that caused the light
map update code to segfault.
I had originally planned on mixing the stage management with general
texture support code like I did in glsl, but I think that was a mistake
and I did keep looking for scrap.[ch] when I wanted to edit something to
do with the scrap...
Cleans up global space and makes it usable in multiple contexts. Also,
max quads dropped to 32k as each frame now has its own vertex buffer to
avoid issues with vertex overwrites (which I have seen). However, all
vertex buffers are in the one memory/buffer object (using offsets) and
the index buffer has been moved into a device-local memory object.
This allows the array in which the command buffers are allocated to be
allocated on the stack using alloca and thus remove the need to
malloc/free of relatively small chunks.
The console background is missing, and scaled vs unscaled (currently
always scaled) 2d, but otherwise everything seems to work. Lots of
places to clean up, though.
