This avoids the possibility of a singularity (and thus the temptation to
use Sys_Error). While the rendering is rubbish, 0 degrees is allowed
because values less than 1 should be allowed, but where does one stop?
170 is the maximum in order to avoid any issues with (near) parallel or
inverted frustum planes (or other fun things) in the low level code.
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.
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.
Only CaptureBGR is per-renderer as the rest of the screenshot code uses
it to do the actual capture (which is target dependent). Vulkan is
currently broken due to capture being an asynchronous process and the
rest of the code expecting capture to be synchronous (also, bgr vs rgb).
The best thing is all renderers now write the same format (currently
png).
This is actually a better solution to the renderer directly accessing
client code than provided by 7e078c7f9c.
Essentially, V_RenderView should not have been calling R_RenderView, and
CL_UpdateScreen should have been calling V_RenderView directly. The
issue was that the renderers expected the world entity model to be valid
at all times. Now, R_RenderView checks the world entity model's validity
and immediately bails if it is not, and R_ClearState (which is called
whenever the client disconnects and thus no longer has a world to
render) clears the world entity model. Thus R_RenderView can (and is)
now called unconditionally from within the renderer, simplifying
renderer-specific variants.
The render plugins have made a bit of a mess of getting at the data and
thus it's a tad confusing how to get at it in different places. Really
needs a proper cleanup :(
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.
This ensures that fov_y is not calculated until after the render view
size is known and thus doesn't become some crazy angle (that happens to
result in a negative tan). Fixes upside-down-quake :)
vid.aspect is removed (for now) as it was not really the right idea (I
really didn't know what I was doing at the time). Nicely, this *almost*
fixes the fov bug on fresh installs: the view is now properly
upside-down rather than just flipped vertically (ie, it's now rotated
180 degrees).
This separate the FOV calculations from other refdef calcs, cleaning up the
renderer proper and making it easier for other parts of the engine (eg,
csqc) to update the fov.
r_screen because of SCR_UpdateScreen, and r_cvar because the cvars
really should never have been in a plugin in the first place (and
r_screen needed access).
Things are still a mess, but a proper cleanup will be a lot of work and
will, really, involve properly splitting quake-specific code* out from
the rest of the renderer.
* data loading and format specific stuff
Where possible, symbols have been made static, prefixed with gl_/GL_ or
moved into the code shared by all renderers. This will make doing plugins
easier but done now for link testing.