Resize window coredump mpv NVScaler: src/shaders/sampling.c:924: fill_ortho_lut: Assertion `w0 + w1 >= 0.0f' failed.

mpv Information

mpv v0.40.0 Copyright © 2000-2025 mpv/MPlayer/mplayer2 projects
libplacebo version: v7.349.0
FFmpeg version: 7.1.1-1+b1
FFmpeg library versions:
   libavcodec      61.19.101
   libavdevice     61.3.100
   libavfilter     10.4.100
   libavformat     61.7.100
   libavutil       59.39.100
   libswresample   5.3.100
   libswscale      8.3.100

Other Information

- Linux version: Debian GNU/Linux 13 (trixie)
- Kernel Version: Linux debian 6.12.38+deb13-amd64
- GPU Model: AMD
- Mesa/GPU Driver Version: 25.0.7-2
- Window Manager and Version: sway 1.10.1-2
- Source of mpv: debian trixie repo
- Latest known working version: 
- Issue started after the following happened: play av1.mkv file and resize window multiple times to trigger the crash.

Reproduction Steps

1. open terminal
2. mpv av1.mkv (AV1 DV 10bit video)
3. activate NVScaler.glsl https://gist.github.com/agyild/7e8951915b2bf24526a9343d951db214
4. hold sway mod key and resize the mpv window multiple!! times from right to left with mouse
5. coredump: mpv: src/shaders/sampling.c:924: fill_ortho_lut: Assertion `w0 + w1 >= 0.0f' failed.

Expected Behavior

no crash

Actual Behavior

src/shaders/sampling.c:924: fill_ortho_lut: Assertion `w0 + w1 >= 0.0f' failed.

Log File

(gdb) bt
#0  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at ./nptl/pthread_kill.c:44
#1  0x000076f5248ed9ff in __pthread_kill_internal (threadid=<optimized out>, signo=6) at ./nptl/pthread_kill.c:89
#2  0x000076f524898cc2 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
#3  0x000076f5248814ac in __GI_abort () at ./stdlib/abort.c:73
#4  0x000076f524881420 in __assert_fail_base (fmt=<optimized out>, assertion=<optimized out>, file=<optimized out>, line=924, 
    function=<optimized out>) at ./assert/assert.c:118
#5  0x000076f5248916dc in __assert_fail (assertion=<optimized out>, file=<optimized out>, line=<optimized out>, function=<optimized out>)
    at ./assert/assert.c:127
#6  0x000076f5256a7148 in fill_ortho_lut (data=<optimized out>, params=<optimized out>) at src/shaders/sampling.c:924
#7  0x000076f5256a55d3 in sh_lut (sh=sh@entry=0x76f4dc4916b0, params=params@entry=0x76f5037f8390) at src/shaders/lut.c:485
#8  0x000076f5256aab53 in pl_shader_sample_ortho2 (sh=0x76f4dc4916b0, src=src@entry=0x76f5037f8520, params=params@entry=0x76f5037f85e0)
    at src/shaders/sampling.c:1024
#9  0x000076f52567fb2a in dispatch_sampler (pass=pass@entry=0x76f5037f8d30, sh=0x76f4dc492080, sampler=sampler@entry=0x76f4dc4a76e8, 
    usage=usage@entry=SAMPLER_CONTRAST, target_tex=target_tex@entry=0x76f4dd920150, src=src@entry=0x76f5037f8850) at src/renderer.c:749
#10 0x000076f5256827f9 in get_feature_map (pass=0x76f5037f8d30) at src/renderer.c:2077
#11 pass_convert_colors (pass=pass@entry=0x76f5037f8d30) at src/renderer.c:2195
#12 0x000076f525688f78 in pl_render_image (rr=rr@entry=0x76f4dc4a7640, pimage=pimage@entry=0x76f4dc745c30, 
    ptarget=ptarget@entry=0x76f5037fcbd0, params=params@entry=0x76f5037fcab0) at src/renderer.c:3152
#13 0x000076f52568a224 in pl_render_image_mix (rr=<optimized out>, images=images@entry=0x76f5037fc740, 
    ptarget=ptarget@entry=0x76f5037fcbd0, params=params@entry=0x76f5037fcab0) at src/renderer.c:3688
#14 0x000062eb2fc2562f in draw_frame (vo=0x62eb40b61b30, frame=<optimized out>) at ../video/out/vo_gpu_next.c:1135
#15 0x000062eb2fc13e31 in render_frame (vo=0x62eb40b61b30) at ../video/out/vo.c:1010

mpv --gpu-debug --log-file=output.txt av1.mkv

https://0x0.st/8hyB.txt

Sample Files

No response

I carefully read all instruction and confirm that I did the following:

• I tested with the latest mpv version to validate that the issue is not already fixed.
• I provided all required information including system and mpv version.
• I produced the log file with the exact same set of files, parameters, and conditions used in "Reproduction Steps", with the addition of --log-file=output.txt.
• I produced the log file while the behaviors described in "Actual Behavior" were actively observed.
• I attached the full, untruncated log file.
• I attached the backtrace in the case of a crash.

Reproduce the crash with mpv av1.mkv, NVScaler.glsl, and repeated sway window resizing. Start at libplacebo's src/shaders/sampling.c:924, then trace the callers in src/shaders/lut.c:485 and src/shaders/renderer.c:749; mpv enters through video/out/vo_gpu_next.c:1135. Done means the reported resize sequence no longer aborts at fill_ortho_lut.