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 does mean that the gl and sw renderers can no longer call
S_ExtraUpdate, but really, they shouldn't be anyway. And I seem to
remember it not really helping (been way too long since quake ran that
slowly for me).
The gl water warp ones have been useless since very early on due to not
doing water warp in gl (vertex warping just didn't work well), and the
recent water warp implementation doesn't need those hacks. The rest of
the removed flags just aren't needed for anything. SURF_DRAWNOALPHA
might get renamed, but should be useful for translucent bsp surfaces
(eg, vines in ad_tears).
One more step towards BSP thread-safety. This one brought with it a very
noticeable speed boost (ie, not lost in the noise) thanks to the face
visframes being in tightly packed groups instead of 128 bytes apart,
though the sw render's boost is lost in the noise (but it's very
fill-rate limited).
This is next critical step to making BSP rendering thread-safe.
visframe was replaced with cluster (not used yet) in anticipation of BSP
cluster reconstruction (which will be necessary for dealing with large
maps like ad_tears).
The main goal was to get visframe out of mnode_t to make it thread-safe
(each thread can have its own visframe array), but moving the plane info
into mnode_t made for better data access patters when traversing the bsp
tree as the plane is right there with the child indices. Nicely, the
size of mnode_t is the same as before (64 bytes due to alignment), with
4 bytes wasted.
Performance-wise, there seems to be very little difference. Maybe
slightly slower.
The unfortunate thing about the change is the plane distance is negated,
possibly leading to some confusion, particularly since the box and
sphere culling functions were affected. However, this is so point-plane
distance calculations can be done with a single 4d dot product.
The map uses 41% of a 4k light map scrap, and 512 texture descriptors
wasn't enough for vulkan. Ouch. I do need to get cvars on these things,
but this will do for now (decades later...)
This gives a rather significant speed boost to timedemo demo1: from
about 2300-2360fps up to 2520-2600fps, at least when using
multi-texture.
Since it was necessary for testing the scrap, gl got the ability to set
the console background texture, too.
The parsing of light data from maps is now in the client library, and
basic light management is in scene. Putting the light loading code into
the Vulkan renderer was a mistake I've wanted to correct for a while.
The client code still needs a bit of cleanup, but the basics are working
nicely.
This replaces *_NewMap with *_NewScene and adds SCR_NewScene to handle
loading a new map (for quake) in the renderer, and will eventually be
how any new scene is loaded.
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.
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 fixes (*ahem*) the vulkan renderer segfaulting when attempting to
take a screenshot. However, the image is upside down. Also, remote
snapshots and demo capture are broken for the moment.
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).
I meant to do this a while ago but forgot about it. Things are a bit of
a mess in that the renderer knows too much about entities, but
eventually the renderer will know about only things to render (meshes,
particles, etc).
Now GL perspective matrix setup matches that of GLSL and Vulkan, and
GL's z_up matrix matches GLSL's (as it should, since they're really
going through the same API). GL also needs the depth adjustmet matrix
now. Other than having to google the docs for glFrustum, there's nothing
wrong with the function itself, but it's nice to have direct control
over the matrices.
In the process, I discovered how horribly confused I've been at times
with respect to the handedness of GL and Quake: GL is right-handed
(y-up, z-out, x-right), as is Quake itself (but z-up, y-left, x-in), but
as the perspective matrix used in the three renderers expects z-in,
having x-right and y-up makes the matrix effectively left-handed (not
for Vulkan though, because there it's y-down, x-right, z-up, so
right-handed again).
Of course, it's not as correct as glsl or sw due to using polygons and
uvs rather than a fragment shader (not that such is out of the question
since GL 3.0 is requested, but I don't feel like getting shaders going
just for a couple of post-processing effects in an obsolete renderer).
The cvar setup for particles is a bit wonky in that the arrays get
initialized using the default max particle count but never updated.
Though things could be improved some more, this solution works (and has
been more or less copied to gl, but I couldn't reproduce the crash
there, or even the valgrind error).
Again, gl/vulkan not working yet (on the assumption that sw would be
trickier).
Fisheye overrides water warp because updating the projection map every
frame is far too expensive.
I've added a post-process pass to the interface in order to hide the
implementation details, but I'm not sure I'm happy about how the
multi-pass rendering for cube maps is handled (or having the frame
buffers as exposed as they are), but mainly because Vulkan will make
implementation interesting.
Other than the view model (undecided on the approach) this has
R_RenderView pretty much pulled out of the low level renderers. With
this, I'll be able to focus on scene handling for a bit then getting
shadows and fisheye working (again for fisheye).
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.
gl_overbright_f shouldn't need to run through any entity queues to
update the light maps as only the world model has light maps, and
hitting the world model should hit all its sub-models.
Move r_pcurrentvertbase into the sw renderer, cleaning up gl's use of
(not really needed there). Not ready to move r_bsp into the main bin yet
as there are linking issues since only the low-level code references any
of its symbols.
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.
While the scheme of using our own allocated did work just fine, fisheye
rendering uses glGenTextures which caused a texture id clash and thus
invalid operations (the cube map texture happened to be the same as the
console background texture). Sure, I could have just "fixed" the fisheye
init code, but this brings gl closer in line with glsl (which makes
extensive use of glGenTextures and glDeleteTextures). This doesn't fix
any texture leaks gl has (plenty, I imagine), but it's a step in the
right direction.
Only for gl and sw at the moment (want to merge things further before I
do anything for glsl or vulkan). However, with with I've learned getting
gl and sw to work, glsl and vulkan will be trivial.
R_RecursiveLightUpdate has been obsolete for a very long time, and
R_Mirror is just wrong (needs envmaps etc, wonder if it can be done in
the fixed function code using skyclip?)
Finally. I never liked it (felt bad adding it in the first place), and
it has caused confusion with function and global variable names, but it
did let me get the render plugins working.
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?)).
So far, in gl and glsl, but viewposition is much clearer than r_origin
(despite being the same thing), and modelorg is just confusing (I think
it's the view position relative to the current model).
GL still has its own functions for enabling and disabling fog while
rendering, but GLSL doesn't need such (thanks to the shaders), nor will
vulkan (and the software renderers don't support fog).
