While QF doesn't currently use nanoseconds, having access to a clock
that is not affected by setting system time is nice, and as a bonus, can
handle suspends should the need arise.
At the low level, only unions can cause a set to grow. Of course, things
get interesting at the higher level when infinite (inverted) sets are
mixed in.
Instead of printing every representable member of an infinite set (ie,
up to element 63 in a set that can hold 64 elements), only those
elements up to one after the last non-member are listed. For example,
{...} - {2 3} -> {0 1 4 ...}
This makes reading (and testing!) infinite sets much easier.
Most of the set ops were always endian-agnostic since they were simply
operating on multiple bits in parallel, but individual element
add/remove/test was very endian-dependent. For the most part, this
didn't matter, but it does matter very much when loading external data
into a set or writing the data out (eg, for PVS).
Attempting to vis ad_tears drags a few lurking bugs out of
SmallestEnclosingBall_vf: poor calculation of 2-point affine space, poor
handling of duplicate points and dropped support points, poor
calculation of the new center (related to duplicate points), and
insufficient iterations for large point sets. qfvis (modified for
cluster spheres) now loads ad_tears.
As per usual, fp math finds a way to confound any epsilon test. So
rather than relying entirely on test_support_points, check the distance
from the sphere center to the affine point and break out of the loop if
the distance is small enough (< 1% of the current radius). This allows
qfvis to load ad_tears without hacks.
Scaling the checks by 1e-6 was a little too tight for very small
triangles, but 1e-5 seems to work well. This fixes SEB getting stuck for
a ridiculously small (for quake) triangle in ad_tears (probably resulted
from some bad math in qfbsp when generating the portal file from the
bsp).
For now, the functions check for a null hunk pointer and use the global
hunk (initialized via Memory_Init) if necessary. However, Hunk_Init is
available (and used by Memory_Init) to create a hunk from any arbitrary
memory block. So long as that block is 64-byte aligned, allocations
within the hunk will remain 64-byte aligned.
I need to write some automated tests for this, and reading of course,
but 1 and two byte outputs look correct. Kind of sad it took sixteen
years to get around to attempting to use the code :(
I knew counting bits individually was slow, but it never really mattered
until now. However, I didn't expect such a dramatic boost just by going
to mapping bytes to bit counts. 16-bit words would be faster still, but
the 64kB lookup table would probably start hurting cache performance,
and 32-bit words (4GB table) definitely would ruin the cache. The
universe isn't big enough for 64-bits :)
After seeing set_size and thinking it redundant (thought it returned the
capacity of the set until I checked), I realized set_count would be a
much better name (set_count (node->successors) in qfcc does make much
more sense).
Having set_expand exposed is useful for loading data into a set.
However, it turns out there was a bug in its size calculation in that
when the requested set size was a multiple of SET_BITS (and greater than
the current set size), the new set size one be SET_BITS larger than
requested. There's now some tests for this :)
This fixes a bug when loading bsp29 files that resulted in leaf nodes
having bogus bounding boxes if any coordinates were negative (and thus
dynamic lights, and probably all sorts of other things) being broken.
And it took me only 9 years to notice :P
This reduces the overhead needed to manage the memory blocks as the
blocks are guaranteed to be page-aligned. Also, the superblock is now
alllocated from within one of the memory blocks it manages. While this
does slightly reduce the available cachelines within the first block (by
one or two depending on 32 vs 64 bit pointers), it removes the need for
an extra memory allocation (probably via malloc) for the superblock.
The uptime display had not been updated for the offset Sys_DoubleTime,
so add Sys_DoubleTimeBase to make it easy to use Sys_DoubleTime as
uptime.
Line up the layout of the client list was not consistent for drop and
qport.
This failed with errors such as:
from ./include/QF/simd/vec4d.h:32,
from libs/util/simd.c:37:
./include/QF/simd/vec4d.h: In function ‘qmuld’:
/usr/lib/gcc/x86_64-pc-linux-gnu/10.3.0/include/avx2intrin.h:1049:1: error: inlining failed in call to ‘always_inline’ ‘_mm256_permute4x64_pd’: target specific option mismatch
1049 | _mm256_permute4x64_pd (__m256d __X, const int __M)
If Sys_Shutdown gets called twice, particularly if a shutdown callback
hangs and the program is killed with INT or QUIT, shutdown_list would be
in an invalid state. Thus, get the required data (function pointer and
data pointer) from the list element, then unlink the element before
calling the function. This ensures that a reinvocation of Sys_Shutdown
continues from the next callback or ends cleanly. Fixes a segfault when
killing testsound while using the oss output (it hangs on shutdown).
Fuzzy bsearch is useful for finding an entry in a prefix sum array
(value is >= ele[0], < ele[1]), and the reentrant version is good when
data needs to be passed to the compare function. Adapted from the code
used in pr_resolve.
A bit of a mess for optimized vs unoptimized, but the tests acknowledge
the differences in precision while checking that the code produces the
right results allowing for that precision.
It seems that i686 code generation is all over the place reguarding sse2
vs fp, with the resulting differences in carried precision. I'm not sure
I'm happy with the situation, but at least it's being tested to a
certain extent. Not sure if this broke basic (no sse) i686 tests.
GCC does a fairly nice job of producing code for vector types when the
hardware doesn't support SIMD, but it seems to break certain math
optimization rules due to excess precision (?). Still, it works well
enough for the core engine, but may not be well suited to the tools.
However, so far, only qfvis uses vector types (and it's not tested yet),
and tools should probably be used on suitable machines anyway (not
forces, of course).
I don't know that the cache line size is 64 bytes on 32 bit systems, but
it should be ok to assume that 64-byte alignment behaves well on systems
with smaller cache lines so long as they are powers of two. This does
mean there is some waste on 32-bit systems, but it should be fairly
minimal (32 bytes per memblock, which manages page sized regions).
