Thomas Debesse (c5ecfe71) at 03 Jul 02:12

q3map2/light_bounce: prevent infinite loop on obscure bias compute

New code produces same result without loop at all, so it cannot fall in infinite loop, and it is faster in use cases requiring more than one loop in previous code.

The Unvanquished vega map is known to trigger the bug: github.com/UnvanquishedAssets/map-vega_src.dpkdir I reproduced it multiple time on various hardware (8 core FX-9590, 12 core/24 thread Ryzen 9 3900X) with commit af40508 and using final compilation profile edited to use -fastbounce instead of -fast option.

The symptom is simple, q3map2 stucks there (with an 8 core FX-9590 CPU):

--- Radiosity (bounce 1 of 8) ---
--- RadCreateDiffuseLights ---
0...1...2...3..

Or somewhere else in that progression bar given your hardware and the amount of core your CPU has.

For example, with a 12 core / 24 thread Ryzen 9 3900X CPU, q3map2 stucks there:

--- Radiosity (bounce 1 of 8) ---
--- RadCreateDiffuseLights ---
0...1...2...3...4..

When stuck, all the CPU cores are running 100% but the thread never returns (a strace can reveals it, a gdb backtrace too).

Thanks to @slipher for the precious advices and improving my first attempt to fix it.

For more information on the issue, I asked:

which negative value never can become positive when incremented infinitely?

slipher said:

for a double, any value less than -2^53 would have this property don't know for float off the top of my head

But then, it means that's theoretically verified this loop was able to run forever in some case.

I don't know what this code is doing anyway, but at least we can keep the behaviour without requiring to understand it.

For information, this is how q3map2 processes look when the issue happens:

$ strace -p 52551
strace: Process 52551 attached
futex(0x7f4bdffff9d0, FUTEX_WAIT, 183960, NULL

$ gdb --pid=52551
GNU gdb (Ubuntu 9.1-0ubuntu1) 9.1
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Attaching to process 52551
[New LWP 183960]
[New LWP 183961]
[New LWP 183962]
[New LWP 183963]
[New LWP 183964]
[New LWP 183965]
[New LWP 183966]
[New LWP 183967]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
__pthread_clockjoin_ex (threadid=139963857368832, thread_return=0x0, clockid=, abstime=, block=)
    at pthread_join_common.c:145
145	pthread_join_common.c: Aucun fichier ou dossier de ce type.
(gdb) thread apply all bt

Thread 9 (Thread 0x7f4bddffb700 (LWP 183967)):
#0  0x0000557fd26a25fd in RadSampleImage (pixels=0x7f4bf16c2010 "egh\377egh\377egh\377ggi\377iik\377ggi\377fhj\377ehi\377gij\377hii\377ghg\377ghh\377fgg\377ehh\377fii\377eij\377fhi\377ghi\377hij\377ghj\377ghj\377ggj\377dgi\377ehj\377egi\377ehj\377gik\377fij\377fii\377ehg\377egg\377ehi\377egi\377egi\377egh\377dgg\377dgg\377dgf\377dgg\377egi\377fij\377ehi\377dgg\377cfg\377dgg\377dgg\377dgg\377cfg\377dfg\377ffi\377"..., width=512, height=512, st=0x7f4bddfc9c40, color=0x7f4bddfc9c80) at …/netradiant/tools/quake3/q3map2/light_bounce.c:221
#1  0x0000557fd26a312c in RadSample (lightmapNum=0, ds=0x7f4be6444d80, lm=0x557fdaf48d10, si=0x7f4bf2ae61c0, rw=0x7f4bddfe9e20, average=0x7f4bddfc9d90, gradient=0x7f4bddfd9da0, style=0x7f4bddfc9d1c) at …/netradiant/tools/quake3/q3map2/light_bounce.c:373
#2  0x0000557fd26a3a56 in RadSubdivideDiffuseLight (lightmapNum=0, ds=0x7f4be6444d80, lm=0x557fdaf48d10, si=0x7f4bf2ae61c0, scale=1, subdivide=256, original=qtrue, rw=0x7f4bddfe9e20, cw=0x7f4bddff9e90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:484
#3  0x0000557fd26a4b46 in RadLightForTriangles (num=13612, lightmapNum=0, lm=0x557fdaf48d10, si=0x7f4bf2ae61c0, scale=1, subdivide=256, cw=0x7f4bddff9e90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:676
#4  0x0000557fd26a58cd in RadLight (num=13612) at …/netradiant/tools/quake3/q3map2/light_bounce.c:884
#5  0x0000557fd2675fe1 in ThreadWorkerFunction (threadnum=7) at …/netradiant/tools/quake3/common/threads.c:101
#6  0x00007f4bf5309609 in start_thread (arg=) at pthread_create.c:477
#7  0x00007f4bf4ed2103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 8 (Thread 0x7f4bde7fc700 (LWP 183966)):
#0  0x0000557fd26a25fa in RadSampleImage (pixels=0x7f4bf16c2010 "egh\377egh\377egh\377ggi\377iik\377ggi\377fhj\377ehi\377gij\377hii\377ghg\377ghh\377fgg\377ehh\377fii\377eij\377fhi\377ghi\377hij\377ghj\377ghj\377ggj\377dgi\377ehj\377egi\377ehj\377gik\377fij\377fii\377ehg\377egg\377ehi\377egi\377egi\377egh\377dgg\377dgg\377dgf\377dgg\377egi\377fij\377ehi\377dgg\377cfg\377dgg\377dgg\377dgg\377cfg\377dfg\377ffi\377"..., width=512, height=512, st=0x7f4bde7cac40, color=0x7f4bde7cac80) at …/netradiant/tools/quake3/q3map2/light_bounce.c:221
#1  0x0000557fd26a312c in RadSample (lightmapNum=0, ds=0x7f4be644c120, lm=0x557fdaf4e110, si=0x7f4bf2ae61c0, rw=0x7f4bde7eae20, average=0x7f4bde7cad90, gradient=0x7f4bde7dada0, style=0x7f4bde7cad1c) at …/netradiant/tools/quake3/q3map2/light_bounce.c:373
#2  0x0000557fd26a3a56 in RadSubdivideDiffuseLight (lightmapNum=0, ds=0x7f4be644c120, lm=0x557fdaf4e110, si=0x7f4bf2ae61c0, scale=1, subdivide=256, original=qtrue, rw=0x7f4bde7eae20, cw=0x7f4bde7fae90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:484
#3  0x0000557fd26a4b46 in RadLightForTriangles (num=13812, lightmapNum=0, lm=0x557fdaf4e110, si=0x7f4bf2ae61c0, scale=1, subdivide=256, cw=0x7f4bde7fae90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:676
#4  0x0000557fd26a58cd in RadLight (num=13812) at …/netradiant/tools/quake3/q3map2/light_bounce.c:884
#5  0x0000557fd2675fe1 in ThreadWorkerFunction (threadnum=6) at …/netradiant/tools/quake3/common/threads.c:101
#6  0x00007f4bf5309609 in start_thread (arg=) at pthread_create.c:477
#7  0x00007f4bf4ed2103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 7 (Thread 0x7f4bdeffd700 (LWP 183965)):
#0  0x0000557fd26a25fd in RadSampleImage (pixels=0x7f4bf16c2010 "egh\377egh\377egh\377ggi\377iik\377ggi\377fhj\377ehi\377gij\377hii\377ghg\377ghh\377fgg\377ehh\377fii\377eij\377fhi\377ghi\377hij\377ghj\377ghj\377ggj\377dgi\377ehj\377egi\377ehj\377gik\377fij\377fii\377ehg\377egg\377ehi\377egi\377egi\377egh\377dgg\377dgg\377dgf\377dgg\377egi\377fij\377ehi\377dgg\377cfg\377dgg\377dgg\377dgg\377cfg\377dfg\377ffi\377"..., width=512, height=512, st=0x7f4bdefcbc40, color=0x7f4bdefcbc80) at …/netradiant/tools/quake3/q3map2/light_bounce.c:221
#1  0x0000557fd26a312c in RadSample (lightmapNum=0, ds=0x7f4be6444c58, lm=0x557fdaf4df10, si=0x7f4bf2ae61c0, rw=0x7f4bdefebe20, average=0x7f4bdefcbd90, gradient=0x7f4bdefdbda0, style=0x7f4bdefcbd1c) at …/netradiant/tools/quake3/q3map2/light_bounce.c:373
#2  0x0000557fd26a3a56 in RadSubdivideDiffuseLight (lightmapNum=0, ds=0x7f4be6444c58, lm=0x557fdaf4df10, si=0x7f4bf2ae61c0, scale=1, subdivide=256, original=qtrue, rw=0x7f4bdefebe20, cw=0x7f4bdeffbe90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:484
#3  0x0000557fd26a4b46 in RadLightForTriangles (num=13610, lightmapNum=0, lm=0x557fdaf4df10, si=0x7f4bf2ae61c0, scale=1, subdivide=256, cw=0x7f4bdeffbe90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:676
#4  0x0000557fd26a58cd in RadLight (num=13610) at …/netradiant/tools/quake3/q3map2/light_bounce.c:884
#5  0x0000557fd2675fe1 in ThreadWorkerFunction (threadnum=5) at …/netradiant/tools/quake3/common/threads.c:101
#6  0x00007f4bf5309609 in start_thread (arg=) at pthread_create.c:477
#7  0x00007f4bf4ed2103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 6 (Thread 0x7f4bdf7fe700 (LWP 183964)):
#0  0x0000557fd26a25fa in RadSampleImage (pixels=0x7f4bf16c2010 "egh\377egh\377egh\377ggi\377iik\377ggi\377fhj\377ehi\377gij\377hii\377ghg\377ghh\377fgg\377ehh\377fii\377eij\377fhi\377ghi\377hij\377ghj\377ghj\377ggj\377dgi\377ehj\377egi\377ehj\377gik\377fij\377fii\377ehg\377egg\377ehi\377egi\377egi\377egh\377dgg\377dgg\377dgf\377dgg\377egi\377fij\377ehi\377dgg\377cfg\377dgg\377dgg\377dgg\377cfg\377dfg\377ffi\377"..., width=512, height=512, st=0x7f4bdf7ccc40, color=0x7f4bdf7ccc80) at …/netradiant/tools/quake3/q3map2/light_bounce.c:221
#1  0x0000557fd26a312c in RadSample (lightmapNum=0, ds=0x7f4be644eff4, lm=0x557fdaefbb10, si=0x7f4bf2ae61c0, rw=0x7f4bdf7ece20, average=0x7f4bdf7ccd90, gradient=0x7f4bdf7dcda0, style=0x7f4bdf7ccd1c) at …/netradiant/tools/quake3/q3map2/light_bounce.c:373
#2  0x0000557fd26a3a56 in RadSubdivideDiffuseLight (lightmapNum=0, ds=0x7f4be644eff4, lm=0x557fdaefbb10, si=0x7f4bf2ae61c0, scale=1, subdivide=256, original=qtrue, rw=0x7f4bdf7ece20, cw=0x7f4bdf7fce90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:484
#3  0x0000557fd26a4b46 in RadLightForTriangles (num=13893, lightmapNum=0, lm=0x557fdaefbb10, si=0x7f4bf2ae61c0, scale=1, subdivide=256, cw=0x7f4bdf7fce90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:676
#4  0x0000557fd26a58cd in RadLight (num=13893) at …/netradiant/tools/quake3/q3map2/light_bounce.c:884
#5  0x0000557fd2675fe1 in ThreadWorkerFunction (threadnum=4) at …/netradiant/tools/quake3/common/threads.c:101
#6  0x00007f4bf5309609 in start_thread (arg=) at pthread_create.c:477
#7  0x00007f4bf4ed2103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7f4be91a1700 (LWP 183963)):
#0  0x0000557fd26a25fa in RadSampleImage (pixels=0x7f4bf16c2010 "egh\377egh\377egh\377ggi\377iik\377ggi\377fhj\377ehi\377gij\377hii\377ghg\377ghh\377fgg\377ehh\377fii\377eij\377fhi\377ghi\377hij\377ghj\377ghj\377ggj\377dgi\377ehj\377egi\377ehj\377gik\377fij\377fii\377ehg\377egg\377ehi\377egi\377egi\377egh\377dgg\377dgg\377dgf\377dgg\377egi\377fij\377ehi\377dgg\377cfg\377dgg\377dgg\377dgg\377cfg\377dfg\377ffi\377"..., width=512, height=512, st=0x7f4be916fc40, color=0x7f4be916fc80) at …/netradiant/tools/quake3/q3map2/light_bounce.c:221
#1  0x0000557fd26a312c in RadSample (lightmapNum=0, ds=0x7f4be644bff8, lm=0x557fdae71110, si=0x7f4bf2ae61c0, rw=0x7f4be918fe20, average=0x7f4be916fd90, gradient=0x7f4be917fda0, style=0x7f4be916fd1c) at …/netradiant/tools/quake3/q3map2/light_bounce.c:373
#2  0x0000557fd26a3a56 in RadSubdivideDiffuseLight (lightmapNum=0, ds=0x7f4be644bff8, lm=0x557fdae71110, si=0x7f4bf2ae61c0, scale=1, subdivide=256, original=qtrue, rw=0x7f4be918fe20, cw=0x7f4be919fe90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:484
#3  0x0000557fd26a4b46 in RadLightForTriangles (num=13810, lightmapNum=0, lm=0x557fdae71110, si=0x7f4bf2ae61c0, scale=1, subdivide=256, cw=0x7f4be919fe90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:676
#4  0x0000557fd26a58cd in RadLight (num=13810) at …/netradiant/tools/quake3/q3map2/light_bounce.c:884
#5  0x0000557fd2675fe1 in ThreadWorkerFunction (threadnum=3) at …/netradiant/tools/quake3/common/threads.c:101
#6  0x00007f4bf5309609 in start_thread (arg=) at pthread_create.c:477
#7  0x00007f4bf4ed2103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7f4be89a0700 (LWP 183962)):
#0  0x0000557fd26a25fa in RadSampleImage (pixels=0x7f4bf16c2010 "egh\377egh\377egh\377ggi\377iik\377ggi\377fhj\377ehi\377gij\377hii\377ghg\377ghh\377fgg\377ehh\377fii\377eij\377fhi\377ghi\377hij\377ghj\377ghj\377ggj\377dgi\377ehj\377egi\377ehj\377gik\377fij\377fii\377ehg\377egg\377ehi\377egi\377egi\377egh\377dgg\377dgg\377dgf\377dgg\377egi\377fij\377ehi\377dgg\377cfg\377dgg\377dgg\377dgg\377cfg\377dfg\377ffi\377"..., width=512, height=512, st=0x7f4be896ec40, color=0x7f4be896ec80) at …/netradiant/tools/quake3/q3map2/light_bounce.c:221
#1  0x0000557fd26a312c in RadSample (lightmapNum=0, ds=0x7f4be6444bc4, lm=0x557fdaea4310, si=0x7f4bf2ae61c0, rw=0x7f4be898ee20, average=0x7f4be896ed90, gradient=0x7f4be897eda0, style=0x7f4be896ed1c) at …/netradiant/tools/quake3/q3map2/light_bounce.c:373
#2  0x0000557fd26a3a56 in RadSubdivideDiffuseLight (lightmapNum=0, ds=0x7f4be6444bc4, lm=0x557fdaea4310, si=0x7f4bf2ae61c0, scale=1, subdivide=256, original=qtrue, rw=0x7f4be898ee20, cw=0x7f4be899ee90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:484
#3  0x0000557fd26a4b46 in RadLightForTriangles (num=13609, lightmapNum=0, lm=0x557fdaea4310, si=0x7f4bf2ae61c0, scale=1, subdivide=256, cw=0x7f4be899ee90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:676
#4  0x0000557fd26a58cd in RadLight (num=13609) at …/netradiant/tools/quake3/q3map2/light_bounce.c:884
#5  0x0000557fd2675fe1 in ThreadWorkerFunction (threadnum=2) at …/netradiant/tools/quake3/common/threads.c:101
#6  0x00007f4bf5309609 in start_thread (arg=) at pthread_create.c:477
#7  0x00007f4bf4ed2103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7f4be4d10700 (LWP 183961)):
#0  0x0000557fd26a25e8 in RadSampleImage (pixels=0x7f4bf16c2010 "egh\377egh\377egh\377ggi\377iik\377ggi\377fhj\377ehi\377gij\377hii\377ghg\377ghh\377fgg\377ehh\377fii\377eij\377fhi\377ghi\377hij\377ghj\377ghj\377ggj\377dgi\377ehj\377egi\377ehj\377gik\377fij\377fii\377ehg\377egg\377ehi\377egi\377egi\377egh\377dgg\377dgg\377dgf\377dgg\377egi\377fij\377ehi\377dgg\377cfg\377dgg\377dgg\377dgg\377cfg\377dfg\377ffi\377"..., width=512, height=512, st=0x7f4be4cdec40, color=0x7f4be4cdec80) at …/netradiant/tools/quake3/q3map2/light_bounce.c:222
#1  0x0000557fd26a312c in RadSample (lightmapNum=0, ds=0x7f4be6444cec, lm=0x557fdaefb110, si=0x7f4bf2ae61c0, rw=0x7f4be4cfee20, average=0x7f4be4cded90, gradient=0x7f4be4ceeda0, style=0x7f4be4cded1c) at …/netradiant/tools/quake3/q3map2/light_bounce.c:373
#2  0x0000557fd26a3a56 in RadSubdivideDiffuseLight (lightmapNum=0, ds=0x7f4be6444cec, lm=0x557fdaefb110, si=0x7f4bf2ae61c0, scale=1, subdivide=256, original=qtrue, rw=0x7f4be4cfee20, cw=0x7f4be4d0ee90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:484
#3  0x0000557fd26a4b46 in RadLightForTriangles (num=13611, lightmapNum=0, lm=0x557fdaefb110, si=0x7f4bf2ae61c0, scale=1, subdivide=256, cw=0x7f4be4d0ee90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:676
#4  0x0000557fd26a58cd in RadLight (num=13611) at …/netradiant/tools/quake3/q3map2/light_bounce.c:884
#5  0x0000557fd2675fe1 in ThreadWorkerFunction (threadnum=1) at …/netradiant/tools/quake3/common/threads.c:101
#6  0x00007f4bf5309609 in start_thread (arg=) at pthread_create.c:477
#7  0x00007f4bf4ed2103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7f4bdffff700 (LWP 183960)):
#0  0x0000557fd26a25fd in RadSampleImage (pixels=0x7f4bf16c2010 "egh\377egh\377egh\377ggi\377iik\377ggi\377fhj\377ehi\377gij\377hii\377ghg\377ghh\377fgg\377ehh\377fii\377eij\377fhi\377ghi\377hij\377ghj\377ghj\377ggj\377dgi\377ehj\377egi\377ehj\377gik\377fij\377fii\377ehg\377egg\377ehi\377egi\377egi\377egh\377dgg\377dgg\377dgf\377dgg\377egi\377fij\377ehi\377dgg\377cfg\377dgg\377dgg\377dgg\377cfg\377dfg\377ffi\377"..., width=512, height=512, st=0x7f4bdffcdc40, color=0x7f4bdffcdc80) at …/netradiant/tools/quake3/q3map2/light_bounce.c:221
#1  0x0000557fd26a312c in RadSample (lightmapNum=0, ds=0x7f4be644c08c, lm=0x557fdaf48f10, si=0x7f4bf2ae61c0, rw=0x7f4bdffede20, average=0x7f4bdffcdd90, gradient=0x7f4bdffddda0, style=0x7f4bdffcdd1c) at …/netradiant/tools/quake3/q3map2/light_bounce.c:373
#2  0x0000557fd26a3a56 in RadSubdivideDiffuseLight (lightmapNum=0, ds=0x7f4be644c08c, lm=0x557fdaf48f10, si=0x7f4bf2ae61c0, scale=1, subdivide=256, original=qtrue, rw=0x7f4bdffede20, cw=0x7f4bdfffde90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:484
#3  0x0000557fd26a4b46 in RadLightForTriangles (num=13811, lightmapNum=0, lm=0x557fdaf48f10, si=0x7f4bf2ae61c0, scale=1, subdivide=256, cw=0x7f4bdfffde90) at …/netradiant/tools/quake3/q3map2/light_bounce.c:676
#4  0x0000557fd26a58cd in RadLight (num=13811) at …/netradiant/tools/quake3/q3map2/light_bounce.c:884
#5  0x0000557fd2675fe1 in ThreadWorkerFunction (threadnum=0) at …/netradiant/tools/quake3/common/threads.c:101
#6  0x00007f4bf5309609 in start_thread (arg=) at pthread_create.c:477
#7  0x00007f4bf4ed2103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7f4bf5b54f00 (LWP 52551)):
#0  __pthread_clockjoin_ex (threadid=139963857368832, thread_return=0x0, clockid=, abstime=, block=) at pthread_join_common.c:145
#1  0x0000557fd26764db in RunThreadsOn (workcnt=38977, showpacifier=qtrue, func=0x557fd2675fb6 ) at …/netradiant/tools/quake3/common/threads.c:576
#2  0x0000557fd267602e in RunThreadsOnIndividual (workcnt=38977, showpacifier=qtrue, func=0x557fd26a55da ) at …/netradiant/tools/quake3/common/threads.c:110
#3  0x0000557fd26a59c8 in RadCreateDiffuseLights () at …/netradiant/tools/quake3/q3map2/light_bounce.c:918
#4  0x0000557fd269db2c in LightWorld (BSPFilePath=0x7ffca8537f90 "…/maps/vega.bsp", fastLightmapSearch=qtrue, noBounceStore=qtrue) at …/netradiant/tools/quake3/q3map2/light.c:2062
#5  0x0000557fd26a1a00 in LightMain (argc=27, argv=0x7ffca85388f0) at …/netradiant/tools/quake3/q3map2/light.c:3056
#6  0x0000557fd26c8b0e in main (argc=28, argv=0x7ffca85388e8) at …/netradiant/tools/quake3/q3map2/main.c:244

@Garux said on DeFraG discord:

i guess these are img sts and they try to get positive values there normally they are not far from 0, so must be some fucked up projection in the bug case might worth to check for nan/inf even then

It would definitely be interesting to investigate why we get such wrong number there, we can reliably reproduce the bug with this map. But in all case, now that we have a way to reproduce it if we want to investigate, avoiding the infinite loop is good whatever the other bugs that may lie around.

Right, I renamed it Modulo1IfNegative().

Just a nit - modulo 1 would be return f - floor(f);. This does mod 1 only if the number is negative.

New code produces same result without loop at all, so it cannot fall in infinite loop, and it is faster in use cases requiring more than one loop in previous code.

The Unvanquished vega map is known to trigger the bug: github.com/UnvanquishedAssets/map-vega_src.dpkdir I reproduced it multiple time on various hardware (8 core FX-9590, 12 core/24 thread Ryzen 9 3900X) with commit af40508 and using final compilation profile edited to use -fastbounce instead of -fast option.

The symptom is simple, q3map2 stucks there (with an 8 core FX-9590 CPU):

--- Radiosity (bounce 1 of 8) ---
--- RadCreateDiffuseLights ---
0...1...2...3..

Or somewhere else in that progression bar given your hardware and the amount of core your CPU has.

For example, with a 12 core / 24 thread Ryzen 9 3900X CPU, q3map2 stucks there:

--- Radiosity (bounce 1 of 8) ---
--- RadCreateDiffuseLights ---
0...1...2...3...4..

When stuck, all the CPU cores are running 100% but the thread never returns (a strace can reveals it, a gdb backtrace too).

Thanks to @slipher for the precious advices and improving my first attempt to fix it.

For more information on the issue, I asked:

which negative value never can become positive when incremented infinitely?

slipher said:

for a double, any value less than -2^53 would have this property don't know for float off the top of my head

But then, it means that's theoretically verified this loop was able to run forever in some case.

I don't know what this code is doing anyway, but at least we can keep the behaviour without requiring to understand it.

Yes, I have come to the same solution as you ;)

ASE & OBJ model files will be empty if "deformVertexes autosprite" is used when compiling.

Thank you anyway, Garux.

try without deformVertexes autosprite

I provide a file for fast testing:

modeltest.pk3

It is a small map to build as model, in two versions:

modeltest_brushes.map & modeltest_patches.map

Some explanation:

If you compile/convert the file modeltest_brushes.map to have an ASE model then you will have the expected -and correct- ASE file.

If you compile/convert the file modeltest_patches.map then you will have an ASE file with no mesh (zero tris), only the materials are defined.

It seems clear to me that the -patchmeta switch of q3map2 is not working.

I'm trying to create some ASE/OBJ model in Netradiant using a few patch meshes but the output files are empty, -pachmeta doesn't seem to work.

My Netradiant is 1.5.0-20200328

My Netradiant's preset used to compile/convert is:

  [q3map2] -meta -patchmeta -subdivisions 8 "[MapFile]"
  [q3map2] -convert -format ase -shadersasbitmap "[BspFile]"
  [q3map2] -convert -format obj "[BspFile]"

P.D.: The generated BSP is also "empty" as there is nothing to show if I load it in the game. ITOH, everything is right if I made the same model with brushes instead of patches, but this would be an excessive limitation to create models with Netradiant.

Some screenshot of Netradiant output:

♦

It's a refactoring that came along some VFS work done for game features. It would have been possible to add more convolution to not factorize that code but that did not seem a good idea. Having a dedicated VFS code for notex only is as absurd as having some texwindow code only for WAD, and it looks like you're not happy yourself with that dedicated WAD texwindow code. So, you may be happy, VFS factorization is already done, no dedicated VFS for notex anymore!