VSE Render crash when zooming timeline
Closed, ResolvedPublic

Description

System Information
Windows 7 Ultimate, 64-bit, 32GB, 5960x, Nvidia Quadro FX 1800 (Primary) & GeForce 9800 GTX+ (Secondary)
Graphics Tablet: Wacom Bamboo Model: CTF-430 Driver Version 5.2.4-5

Blender Version
Official release(s) unless specified:
Broken: 2.79 (Windows 64-Bit & Ubuntu Linux (ubuntu-17.10-desktop-amd64) w/ Virtual Box Version 5.2.4 r119785 (Qt5.6.2)), 2.79.0-e59cf13 (Windows 64-Bit)

Worked: (N/A)

Short description of error

When rendering in the Video Sequence Editor Blender crashes if you zoom on the timeline.

Exact steps for others to reproduce the error

Windows: https://www.youtube.com/watch?v=2cDWGxDbmWo

Ubuntu Linux: https://www.youtube.com/watch?v=pdbQZ3_cxxM

Related Objects

Christopher Anderssarian (Christopher_Anderssarian) renamed this task from VSE Render crash when Zooming timeline to VSE Render crash when zooming timeline.
Philipp Oeser (lichtwerk) triaged this task as Confirmed priority.

Can confirm this (apparently only happening with mousewheel zoom), will look into it shortly...

... and apparently only happening with a Text Strip rendering (no Sequencer preview window has to be open for this even), crash happening in font handling

1   BLI_addhead                  listbase.c        77   0x2deda1e      
2   blf_glyph_add                blf_glyph.c       313  0x337b632      
3   blf_font_ensure_ascii_table  blf_font.c        125  0x3377c20      
4   blf_font_wrap_apply          blf_font.c        669  0x3379866      
5   blf_font_boundbox__wrap      blf_font.c        767  0x3379d48      
6   BLF_boundbox_ex              blf.c             669  0x3376ab0      
7   do_text_effect               seqeffects.c      3519 0x2af6d53      
8   seq_render_effect_strip_impl sequencer.c       2769 0x2b029dd      
9   do_render_strip_uncached     sequencer.c       3533 0x2b05036      
10  seq_render_strip             sequencer.c       3614 0x2b053ed      
11  seq_render_strip_stack       sequencer.c       3766 0x2b059d1      
12  BKE_sequencer_give_ibuf      sequencer.c       3883 0x2b05f52      
13  do_render_seq                pipeline.c        2740 0x22cd480      
14  do_render_all_options        pipeline.c        2830 0x22cd978      
15  RE_BlenderAnim               pipeline.c        3762 0x22d08b9      
16  render_startjob              render_internal.c 604  0x21b0a9d      
17  do_job_thread                wm_jobs.c         337  0x1c43c44      
18  tslot_thread_start           threads.c         253  0x2e41f25      
19  start_thread                                        0x7ffff095a609 
20  clone                                               0x7ffff0483e6f 
... <More>

hm, seems like font->glyph_cache is cleared by UI_view2d_zoom_cache_reset() somewhere inbetween setting it up in do_text_effect BLF_size and actually needing it later in blf_glyph_add
Not sure if there is a good way to lock here? Or just recreate it on the fly [in the case it was cleared]?

Wrong commit message, sorry!