Grease Pencil: Sculpt Tools Will Revert Back to Add After One Use of Subtract #115313

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Weston-Meade · 2023-11-23T18:59:28+01:00

Weston-Meade commented

2023-11-23 18:59:28 +01:00

System Information
Operating system: Microsoft Windows 11 Home
Graphics card: NVIDIA GeForce RTX 3060 Ti

Blender Version
Broken: 4.0.0 (As shown on splash screen and downloaded from the main website)
Worked: 3.6.6 Stable

Short description of error
When manually switching a sculpt tool from +add to -subtract (As in pressing the GUI button, rather than using the CTRL key), the tool will automatically switch back to +add after using it one time.

(I have tested this on the 4.1.0 Alpha with both my own settings configs and factory default settings with the same result)

Exact steps for others to reproduce the error
Open a 2D Animation file or create a new one.
Draw a stroke of any thickness.
Go into sculpt mode.
Change the tool to any tool that has an alternate mode (+ -) and set the mode to the subtract mode.
Sculpt the stroke once, if it does not change back immediately try sculpting the stroke one more time.

**System Information** Operating system: Microsoft Windows 11 Home Graphics card: NVIDIA GeForce RTX 3060 Ti **Blender Version** Broken: 4.0.0 (As shown on splash screen and downloaded from the main website) Worked: 3.6.6 Stable **Short description of error** When manually switching a sculpt tool from +add to -subtract (As in pressing the GUI button, rather than using the CTRL key), the tool will automatically switch back to +add after using it one time. (I have tested this on the 4.1.0 Alpha with both my own settings configs and factory default settings with the same result) **Exact steps for others to reproduce the error** Open a 2D Animation file or create a new one. Draw a stroke of any thickness. Go into sculpt mode. Change the tool to any tool that has an alternate mode (+ -) and set the mode to the subtract mode. Sculpt the stroke once, if it does not change back immediately try sculpting the stroke one more time.

BugBlend.blend

1010 KiB

Weston-Meade added the

labels 2023-11-23 18:59:29 +01:00

Nika Kutsniashvili commented

2023-11-23 19:07:10 +01:00

I also have that

Pratik Borhade commented

2023-11-24 04:55:54 +01:00

Hi, thanks for the report. Can confirm the regression, checking.

Pratik Borhade added

and removed

labels 2023-11-24 04:56:07 +01:00

Pratik Borhade commented

2023-11-24 06:17:05 +01:00

Caused by 325acb51df
@JacquesLucke @antoniov ^

Caused by 325acb51dfce14421f83a40c338bde22f8602861 @JacquesLucke @antoniov ^

Pratik Borhade commented

2023-11-24 11:21:39 +01:00

Guess I found the fix.

Pratik Borhade self-assigned this 2023-11-24 11:21:49 +01:00

Jacques Lucke commented

2023-11-24 11:31:22 +01:00

The root problem here seems to be that BrushGpencilSettings.sculpt_flag is a mess. It's used with e.g. BRUSH_DIR_IN (from eBrushFlags), with GP_SCULPT_FLAG_TMP_INVERT (from eGP_Sculpt_Flag) and GP_SCULPT_FLAGMODE_APPLY_THICKNESS (from eGP_Sculpt_Mode_Flag).

This caused the issue in the C++ conversion, because of the newly added ENUM_OPERATORS(eGP_Sculpt_Flag, GP_SCULPT_FLAG_TMP_INVERT). The problem is that the passed max value is not actually the max value, even though it looks like it should based on the code.

The fix would be to pass the actual max value into the ENUM_OPERATORS macro. Since the max value is not obvious right now, I'd like to ask @antoniov to look into this.

The root problem here seems to be that `BrushGpencilSettings.sculpt_flag` is a mess. It's used with e.g. `BRUSH_DIR_IN` (from `eBrushFlags`), with `GP_SCULPT_FLAG_TMP_INVERT` (from `eGP_Sculpt_Flag`) and `GP_SCULPT_FLAGMODE_APPLY_THICKNESS` (from `eGP_Sculpt_Mode_Flag`). This caused the issue in the C++ conversion, because of the newly added `ENUM_OPERATORS(eGP_Sculpt_Flag, GP_SCULPT_FLAG_TMP_INVERT)`. The problem is that the passed max value is not actually the max value, even though it looks like it should based on the code. The fix would be to pass the actual max value into the `ENUM_OPERATORS` macro. Since the max value is not obvious right now, I'd like to ask @antoniov to look into this.

Pratik Borhade commented

2023-11-24 11:37:54 +01:00

Following diff fixes the problem:
Below bitwise operation was giving wrong answer after clearing the flag so I tried explicit casting.
But I don't quite understand why we require explicit casting here, shouldn't enum be implicitly treated as int in this operation?

diff --git a/source/blender/editors/gpencil_legacy/gpencil_sculpt_paint.cc b/source/blender/editors/gpencil_legacy/gpencil_sculpt_paint.cc
index b79b41dd5a1..7bd6555333b 100644
--- a/source/blender/editors/gpencil_legacy/gpencil_sculpt_paint.cc
+++ b/source/blender/editors/gpencil_legacy/gpencil_sculpt_paint.cc
@@ -1338,7 +1338,7 @@ static void gpencil_sculpt_brush_exit(bContext *C, wmOperator *op)
   ED_workspace_status_text(C, nullptr);

   /* disable temp invert flag */
-  gso->brush->gpencil_settings->sculpt_flag &= ~GP_SCULPT_FLAG_TMP_INVERT;
+  gso->brush->gpencil_settings->sculpt_flag &= ~static_cast<int>(GP_SCULPT_FLAG_TMP_INVERT);

   /* Update geometry data for tagged strokes. */
   gpencil_update_geometry(gso->gpd);

Following diff fixes the problem: Below bitwise operation was giving wrong answer after clearing the flag so I tried explicit casting. But I don't quite understand why we require explicit casting here, shouldn't enum be implicitly treated as int in this operation? ``` diff --git a/source/blender/editors/gpencil_legacy/gpencil_sculpt_paint.cc b/source/blender/editors/gpencil_legacy/gpencil_sculpt_paint.cc index b79b41dd5a1..7bd6555333b 100644 --- a/source/blender/editors/gpencil_legacy/gpencil_sculpt_paint.cc +++ b/source/blender/editors/gpencil_legacy/gpencil_sculpt_paint.cc @@ -1338,7 +1338,7 @@ static void gpencil_sculpt_brush_exit(bContext *C, wmOperator *op) ED_workspace_status_text(C, nullptr); /* disable temp invert flag */ - gso->brush->gpencil_settings->sculpt_flag &= ~GP_SCULPT_FLAG_TMP_INVERT; + gso->brush->gpencil_settings->sculpt_flag &= ~static_cast<int>(GP_SCULPT_FLAG_TMP_INVERT); /* Update geometry data for tagged strokes. */ gpencil_update_geometry(gso->gpd); ```

Pratik Borhade commented

2023-11-24 11:38:52 +01:00

Oh @JacquesLucke already commented, didn't notice that

Pratik Borhade removed their assignment 2023-11-24 11:39:38 +01:00

Jacques Lucke commented

2023-11-24 11:45:38 +01:00

Your fix should work as well, but I think it would be better to fix the root cause of the bug.

👍 1

Pratik Borhade referenced this issue

2023-12-13 05:48:27 +01:00

Thickness brush in Grease Pencil keeps reverting to add effect #116113

Falk David commented

2024-01-11 18:07:14 +01:00

@antoniov Could you look into this. It seems like right now there is sculpt_flag and sculpt_mode_flag, but sometimes sculpt_flag is using flags from eGP_Sculpt_Mode_Flag or eBrushFlags. There should be some consistency here.

@antoniov Could you look into this. It seems like right now there is `sculpt_flag` and `sculpt_mode_flag`, but sometimes `sculpt_flag` is using flags from `eGP_Sculpt_Mode_Flag` or `eBrushFlags`. There should be some consistency here.

Antonio Vazquez commented

2024-01-12 09:57:03 +01:00

I'm really sorry, but right now I'm very busy working on several personal projects and I don't have the time or energy to dedicate myself to fixing Blender bugs.

👍 1

Falk David added this to the Grease Pencil project 2024-03-08 12:21:32 +01:00

Thomas Dinges commented

2024-03-12 11:21:06 +01:00

Any update here? Would be good to have a solution for 4.1, even if the root cause isn't fixed.