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Crash in sculpt mode using "Smooth" brush and tab with tablet stylus #89164

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opened 2021-06-15 09:08:58 +02:00 by Balazs Oszvald · 26 comments
Balazs Oszvald commented 2021-06-15 09:08:58 +02:00
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System Information
Operating system: Windows 10
Graphics card: GTX 1050Ti (latest studio driver)
Other: Wacom Intuos 5 (latest driver, wireless)

Blender Version
Broken: All versions after 2.90.1
Worked: 2.90.1

Caused by 3e5431fdf4

Short description of error
Crash in sculpt mode with the Draw brush and smoothing (pressing {key Shift}) when using a tablet.

The issue is that ss->cache->detail_directions is NULL in do_enhance_details_brush_task_cb_ex.

Exact steps for others to reproduce the error

  • File > New > Sculpting
  • choose the Smooth brush
  • set Radius to 4px
  • enable Strength Pressure sensitivity (should be ON by default though)
  • use tablet (not mouse) and tap with the stylus, don't drag, repeatedly
  • crash

Original report:

  • Open the attached file
  • Select the Draw brush, hold {key Shift} and tap with the stylus, don't drag, repeatedly on the area shown in the screenshot below.

crash.jpg
crash.blend

Stack trace 3.0.0 Alpha, branch: master, commit date: 2021-06-24 07:12, hash: 6570159929

madd_v3_v3v3fl(float * r, const float * a, const float * b, float f) Line 720	C
do_enhance_details_brush_task_cb_ex(void * userdata, const int n, const TaskParallelTLS * tls) Line 249	C
BLI_task_parallel_range(const int start, const int stop, void * userdata, void(*)(void *, const int, const TaskParallelTLS *) func, const TaskParallelSettings * settings) Line 140	C++
SCULPT_enhance_details_brush(Sculpt * sd, Object * ob, PBVHNode * * nodes, const int totnode) Line 291	C
SCULPT_do_smooth_brush(Sculpt * sd, Object * ob, PBVHNode * * nodes, int totnode) Line 401	C
do_brush_action(Sculpt * sd, Object * ob, Brush * brush, UnifiedPaintSettings * ups) Line 6017	C
do_tiled(Sculpt * sd, Object * ob, Brush * brush, UnifiedPaintSettings * ups, void(*)(Sculpt *, Object *, Brush *, UnifiedPaintSettings *) action) Line 6469	C
do_symmetrical_brush_actions(Sculpt * sd, Object * ob, void(*)(Sculpt *, Object *, Brush *, UnifiedPaintSettings *) action, UnifiedPaintSettings * ups) Line 6552	C
sculpt_stroke_update_step(bContext * C, PaintStroke * UNUSED_stroke, PointerRNA * itemptr) Line 7929	C
paint_brush_stroke_add_step(bContext * C, wmOperator * op, const float * mouse_in, float pressure) Line 637	C
paint_space_stroke(bContext * C, wmOperator * op, const float * final_mouse, float final_pressure) Line 873	C
paint_stroke_modal(bContext * C, wmOperator * op, const wmEvent * event) Line 1553	C
wm_handler_operator_call(bContext * C, ListBase * handlers, wmEventHandler * handler_base, wmEvent * event, PointerRNA * properties, const unsigned char * kmi_idname) Line 2080	C
wm_handlers_do_intern(bContext * C, wmEvent * event, ListBase * handlers) Line 2909	C
wm_handlers_do(bContext * C, wmEvent * event, ListBase * handlers) Line 2957	C
wm_event_do_handlers(bContext * C) Line 3377	C
WM_main(bContext * C) Line 650	C
main(int argc, const unsigned char * * UNUSED_argv_c) Line 562	C

Original crash log
crash_logs.zip

**System Information** Operating system: Windows 10 Graphics card: GTX 1050Ti (latest studio driver) Other: Wacom Intuos 5 (latest driver, wireless) **Blender Version** Broken: All versions after 2.90.1 Worked: 2.90.1 Caused by 3e5431fdf4 **Short description of error** Crash in sculpt mode with the *Draw* brush and smoothing (pressing {key Shift}) when using a tablet. The issue is that `ss->cache->detail_directions` is `NULL` in `do_enhance_details_brush_task_cb_ex`. **Exact steps for others to reproduce the error** - File > New > Sculpting - choose the `Smooth` brush - set `Radius` to 4px - enable `Strength Pressure` sensitivity (should be ON by default though) - use tablet (not mouse) and tap with the stylus, don't drag, repeatedly - crash --- Original report: - Open the attached file - Select the *Draw* brush, hold {key Shift} and tap with the stylus, don't drag, repeatedly on the area shown in the screenshot below. ![crash.jpg](https://archive.blender.org/developer/F10192787/crash.jpg) [crash.blend](https://archive.blender.org/developer/F10192789/crash.blend) Stack trace 3.0.0 Alpha, branch: master, commit date: 2021-06-24 07:12, hash: `6570159929` ``` madd_v3_v3v3fl(float * r, const float * a, const float * b, float f) Line 720 C do_enhance_details_brush_task_cb_ex(void * userdata, const int n, const TaskParallelTLS * tls) Line 249 C BLI_task_parallel_range(const int start, const int stop, void * userdata, void(*)(void *, const int, const TaskParallelTLS *) func, const TaskParallelSettings * settings) Line 140 C++ SCULPT_enhance_details_brush(Sculpt * sd, Object * ob, PBVHNode * * nodes, const int totnode) Line 291 C SCULPT_do_smooth_brush(Sculpt * sd, Object * ob, PBVHNode * * nodes, int totnode) Line 401 C do_brush_action(Sculpt * sd, Object * ob, Brush * brush, UnifiedPaintSettings * ups) Line 6017 C do_tiled(Sculpt * sd, Object * ob, Brush * brush, UnifiedPaintSettings * ups, void(*)(Sculpt *, Object *, Brush *, UnifiedPaintSettings *) action) Line 6469 C do_symmetrical_brush_actions(Sculpt * sd, Object * ob, void(*)(Sculpt *, Object *, Brush *, UnifiedPaintSettings *) action, UnifiedPaintSettings * ups) Line 6552 C sculpt_stroke_update_step(bContext * C, PaintStroke * UNUSED_stroke, PointerRNA * itemptr) Line 7929 C paint_brush_stroke_add_step(bContext * C, wmOperator * op, const float * mouse_in, float pressure) Line 637 C paint_space_stroke(bContext * C, wmOperator * op, const float * final_mouse, float final_pressure) Line 873 C paint_stroke_modal(bContext * C, wmOperator * op, const wmEvent * event) Line 1553 C wm_handler_operator_call(bContext * C, ListBase * handlers, wmEventHandler * handler_base, wmEvent * event, PointerRNA * properties, const unsigned char * kmi_idname) Line 2080 C wm_handlers_do_intern(bContext * C, wmEvent * event, ListBase * handlers) Line 2909 C wm_handlers_do(bContext * C, wmEvent * event, ListBase * handlers) Line 2957 C wm_event_do_handlers(bContext * C) Line 3377 C WM_main(bContext * C) Line 650 C main(int argc, const unsigned char * * UNUSED_argv_c) Line 562 C ``` Original crash log [crash_logs.zip](https://archive.blender.org/developer/F10171996/crash_logs.zip)
Balazs Oszvald commented 2021-06-15 09:08:58 +02:00
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Added subscriber: @BalazsOszvald

Added subscriber: @BalazsOszvald
Pratik Borhade commented 2021-06-15 09:15:34 +02:00
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Added subscriber: @PratikPB2123

Added subscriber: @PratikPB2123
Balazs Oszvald commented 2021-06-22 07:48:10 +02:00
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Same crash produced on Windows 10 21H1, Ryzen 2600x, 64Gb, GTX 1060 (Studio Driver 462.59), Wacom Intuos 3, Blender 2.93.0
crash.zip

Same crash produced on Windows 10 21H1, Ryzen 2600x, 64Gb, GTX 1060 (Studio Driver 462.59), Wacom Intuos 3, Blender 2.93.0 [crash.zip](https://archive.blender.org/developer/F10187477/crash.zip)
Germano Cavalcante commented 2021-06-23 17:08:15 +02:00
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Added subscriber: @mano-wii

Added subscriber: @mano-wii
Germano Cavalcante commented 2021-06-23 17:08:15 +02:00
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Changed status from 'Needs Triage' to: 'Needs User Info'

Changed status from 'Needs Triage' to: 'Needs User Info'
Germano Cavalcante commented 2021-06-23 17:08:15 +02:00
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All crash-logs show that the crash happens in do_enhance_details_brush_task_cb_ex.
But without reproducible steps, unfortunately we can't triage this as a complete bug report.

For the development team to be able to help, there needs to be reproducible steps (start blender, press this, then that and crash).

All crash-logs show that the crash happens in `do_enhance_details_brush_task_cb_ex`. But without reproducible steps, unfortunately we can't triage this as a complete bug report. For the development team to be able to help, there needs to be reproducible steps (start blender, press this, then that and crash).
Robert Guetzkow commented 2021-06-23 17:58:39 +02:00
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Added subscriber: @rjg

Added subscriber: @rjg
Robert Guetzkow commented 2021-06-23 17:58:39 +02:00
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Likely the same underlying issue as #85135

Likely the same underlying issue as #85135
Balazs Oszvald commented 2021-06-23 19:16:34 +02:00
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All crash-logs show that the crash happens in do_enhance_details_brush_task_cb_ex.

Can you direct me what kind of function it is? I would be more than happy to catch this bug.

> All crash-logs show that the crash happens in `do_enhance_details_brush_task_cb_ex`. Can you direct me what kind of function it is? I would be more than happy to catch this bug.
Germano Cavalcante commented 2021-06-23 19:36:14 +02:00
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The crash happens in this function: https://developer.blender.org/diffusion/B/browse/master/source/blender/editors/sculpt_paint/sculpt_smooth.c$213
But we still don't know what the source of the problem is.

The crash happens in this function: https://developer.blender.org/diffusion/B/browse/master/source/blender/editors/sculpt_paint/sculpt_smooth.c$213 But we still don't know what the source of the problem is.
Balazs Oszvald commented 2021-06-23 20:02:30 +02:00
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The crash happens in this function: https://developer.blender.org/diffusion/B/browse/master/source/blender/editors/sculpt_paint/sculpt_smooth.c$213

Thank you, that is valuable help for me!

> The crash happens in this function: https://developer.blender.org/diffusion/B/browse/master/source/blender/editors/sculpt_paint/sculpt_smooth.c$213 Thank you, that is valuable help for me!
Balazs Oszvald commented 2021-06-24 09:50:47 +02:00
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Ok, so the crash happened for me always when using smoothing with the basic "draw" brush. I managed to create a .blend where the crash can be reproduced constantly and without too much effort .
Load the attached .blend, hold down SHIFT and do a few rapid dots (NOT strokes!) with your stylus (NOT mouse) over the area marked in the image.
crash.jpg
crash.blend
I have reproduced it on different Windows systems using Blender 2.93.0, with different Wacom tablets (Intuos 3, Intuos, Cintiq).

Ok, so the crash happened for me always when using smoothing with the basic "draw" brush. I managed to create a .blend where the crash can be reproduced constantly and without too much effort . Load the attached .blend, hold down SHIFT and do a few rapid dots (NOT strokes!) with your stylus (NOT mouse) over the area marked in the image. ![crash.jpg](https://archive.blender.org/developer/F10192787/crash.jpg) [crash.blend](https://archive.blender.org/developer/F10192789/crash.blend) I have reproduced it on different Windows systems using Blender 2.93.0, with different Wacom tablets (Intuos 3, Intuos, Cintiq).
Robert Guetzkow commented 2021-06-24 11:21:12 +02:00
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Changed status from 'Needs User Info' to: 'Confirmed'

Changed status from 'Needs User Info' to: 'Confirmed'
Robert Guetzkow changed title from EXCEPTION_ACCESS_VIOLATION in sculpt mode to Crash in sculpt mode using "Draw" brush and holding Shift 2021-06-24 11:27:05 +02:00
Balazs Oszvald commented 2021-07-31 21:38:12 +02:00
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2.93.2 RC still crashes but 3.0.0 alpha seems to be stable! I'll probably move to 3.0.0 right away and test it more deeply. Kudos to the one who did the magic :)

2.93.2 RC still crashes but 3.0.0 alpha seems to be stable! I'll probably move to 3.0.0 right away and test it more deeply. Kudos to the one who did the magic :)
Germano Cavalcante commented 2021-08-02 15:00:16 +02:00
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Changed status from 'Confirmed' to: 'Resolved'

Changed status from 'Confirmed' to: 'Resolved'
Germano Cavalcante self-assigned this 2021-08-02 15:00:16 +02:00
Germano Cavalcante commented 2021-08-02 15:00:16 +02:00
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Thanks for the update :)

Closing since it was fixed.

If the problem persists, please let us know so we can re-open the report. Don't forget to mention the specific version you tested again.

Thanks for the update :) Closing since it was fixed. If the problem persists, please let us know so we can re-open the report. Don't forget to mention the specific version you tested again.
Balazs Oszvald commented 2021-08-04 10:03:07 +02:00
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It seems, it only solved the problem in the case of the attached crash.blend . In my actual daytime job I got the same crash with the same smooth brush :/ (Blender 3.0.0 Alpha - fb87d236ed) dl_walls.crash.txt

It seems, it only solved the problem in the case of the attached crash.blend . In my actual daytime job I got the same crash with the same smooth brush :/ (Blender 3.0.0 Alpha - fb87d236edb7) [dl_walls.crash.txt](https://archive.blender.org/developer/F10264486/dl_walls.crash.txt)
Pratik Borhade commented 2021-09-13 07:49:20 +02:00
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Changed status from 'Resolved' to: 'Needs Triage'

Changed status from 'Resolved' to: 'Needs Triage'
Pratik Borhade commented 2021-09-13 07:49:20 +02:00
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In my actual daytime job I got the same crash with the same smooth brush :/ (Blender 3.0.0 Alpha - fb87d236ed)

Reopening then.

> In my actual daytime job I got the same crash with the same smooth brush :/ (Blender 3.0.0 Alpha - fb87d236edb7) Reopening then.
Germano Cavalcante was unassigned by Philipp Oeser 2021-09-28 16:17:31 +02:00
Philipp Oeser commented 2021-09-28 16:35:08 +02:00
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Added subscriber: @lichtwerk

Added subscriber: @lichtwerk
Philipp Oeser commented 2021-09-28 16:35:08 +02:00
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Changed status from 'Needs Triage' to: 'Confirmed'

Changed status from 'Needs Triage' to: 'Confirmed'
Philipp Oeser commented 2021-09-28 16:35:08 +02:00
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Can confirm the crash.

Happens mostly with a very small brush.
Can also be reproduced from the default sculpting template, setting the brush size to 4px, smooth brush (Strength Pressure sensitivity ON), use tablet and hit a few dots (not strokes)

Can confirm the crash. Happens mostly with a very small brush. Can also be reproduced from the default sculpting template, setting the brush size to 4px, smooth brush (Strength Pressure sensitivity ON), use tablet and hit a few dots (not strokes)
Philipp Oeser changed title from Crash in sculpt mode using "Draw" brush and holding Shift to Crash in sculpt mode using "Smooth" brush with small radius and tab with tablet stylus 2021-09-28 16:38:49 +02:00
Philipp Oeser self-assigned this 2021-09-28 17:46:51 +02:00
Philipp Oeser commented 2021-09-28 17:46:51 +02:00
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Caused by 3e5431fdf4

Issue is that sculpting could start with using SCULPT_smooth and (because of the Pressure sensitivity dropping to zero) code would switch to SCULPT_enhance_details_brush at stregth zero.
Issue with this though is that this can be in the middle or end of a stroke and the necessary ss->cache->detail_directions are only initialized for the first brush step (see SCULPT_stroke_is_first_brush_step in SCULPT_enhance_details_brush). With these missing, it could only go downhill from there.

Suggest to prevent the "mode-flip" from SCULPT_smooth to SCULPT_enhance_details_brush (happening solely because of pressure strength) by changing the condition.
Now do SCULPT_enhance_details_brush only if strength is below zero and SCULPT_smooth only if strength is above zero.
Skipping exactly zero should be fine since with an influence of zero, the brush step would not do anything anyways.

I think this can happen quite often actually (first assumption of this happening only with small brush radius is wrong -- can happen with all sizes), so will dare setting this to High prio.
Fix incomming.

Caused by 3e5431fdf4 Issue is that sculpting could start with using `SCULPT_smooth` and (because of the Pressure sensitivity dropping to zero) code would switch to `SCULPT_enhance_details_brush` at stregth zero. Issue with this though is that this can be in the middle or end of a stroke and the necessary `ss->cache->detail_directions` are only initialized for the first brush step (see `SCULPT_stroke_is_first_brush_step` in `SCULPT_enhance_details_brush`). With these missing, it could only go downhill from there. Suggest to prevent the "mode-flip" from `SCULPT_smooth` to `SCULPT_enhance_details_brush` (happening solely because of pressure strength) by changing the condition. Now do `SCULPT_enhance_details_brush` only if strength is **below** zero and `SCULPT_smooth` only if strength is **above** zero. Skipping exactly zero should be fine since with an influence of zero, the brush step would not do anything anyways. I think this can happen quite often actually (first assumption of this happening only with small brush radius is wrong -- can happen with all sizes), so will dare setting this to High prio. Fix incomming.
Philipp Oeser changed title from Crash in sculpt mode using "Smooth" brush with small radius and tab with tablet stylus to Crash in sculpt mode using "Smooth" brush and tab with tablet stylus 2021-09-28 17:47:10 +02:00
blender-admin commented 2021-09-28 17:50:50 +02:00
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This issue was referenced by 71f354a825

This issue was referenced by 71f354a825cc339a6af577cf6a704776d02fa77d
blender-admin commented 2021-09-28 17:50:50 +02:00
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This issue was referenced by b80ed8396d

This issue was referenced by b80ed8396d285fd3f63831cb1b6589e7057514ce
Philipp Oeser commented 2021-09-29 15:12:58 +02:00
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Changed status from 'Confirmed' to: 'Resolved'

Changed status from 'Confirmed' to: 'Resolved'
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