Tablet not drawing - moving pen causes drawing to break #79335

New Issue

Phil Smy · 2020-07-28T06:40:45+02:00

Phil Smy commented

2020-07-28 06:40:45 +02:00

System Information
Operating system: MacOS 10.15.5 (19F101)
Graphics card: AMD Radeon Pro 5300M 4 GB
Intel UHD Graphics 630 1536 MB
(I am on a MacBook Pro (16-inch, 2019))

Blender Version
Broken: 2.83.2 2020-07-09, also 2.90.0 2020-07-27

Worked: None

Short description of error
I have 2 graphics tablets - a Huion 610Pro and an XP-PEN Artist 12 - and both exhibit the same behavior: unable to draw in 2d mode.

Exact steps for others to reproduce the error

Open Blender
Choose 2D Animation from the splash screen
Can draw using the mouse
Bring tablet pen onscreen (don't need to click, simply moving the cursor with the pen does it)
Can no longer draw with mouse(!)
Cannot draw with pen

Both tablets work perfectly fine in other applications (eg Photoshop). I actually bought the XPPen because I thought the Huion was old and maybe that was the issue.
The bizarre thing is that simply moving the cursor with the tablet causes the issue. You do NOT need to touch pen to tablet and try to draw.

I tried this with 'clean' settings (i.e Load Default) and also with Emulate 3 Button Mouse.

I also turned on Screencast keys to see if some command was being issued by the tablets, but I see nothing coming through.

**System Information** Operating system: MacOS 10.15.5 (19F101) Graphics card: AMD Radeon Pro 5300M 4 GB Intel UHD Graphics 630 1536 MB (I am on a MacBook Pro (16-inch, 2019)) **Blender Version** Broken: 2.83.2 2020-07-09, also 2.90.0 2020-07-27 Worked: None **Short description of error** I have 2 graphics tablets - a Huion 610Pro and an XP-PEN Artist 12 - and both exhibit the same behavior: unable to draw in 2d mode. **Exact steps for others to reproduce the error** 1) Open Blender 2) Choose 2D Animation from the splash screen 3) Can draw using the mouse 4) Bring tablet pen onscreen (don't need to click, simply moving the cursor with the pen does it) 5) Can no longer draw with mouse(!) 6) Cannot draw with pen Both tablets work perfectly fine in other applications (eg Photoshop). I actually bought the XPPen because I thought the Huion was old and maybe that was the issue. The bizarre thing is that simply moving the cursor with the tablet causes the issue. You do NOT need to touch pen to tablet and try to draw. I tried this with 'clean' settings (i.e Load Default) and also with Emulate 3 Button Mouse. I also turned on Screencast keys to see if some command was being issued by the tablets, but I see nothing coming through.

Phil Smy commented

2020-07-28 06:40:45 +02:00

Added subscriber: @philinjp

Phil Smy commented

2020-07-28 07:55:14 +02:00

Ok, looking around more I found this bug report: https://developer.blender.org/T62565

In it there is discussion of tablet pressure. So, I decided to run Blender 2.83.2 with --debug-events and see, and sure enough that does seem to be the issue.

wm_event_do_handlers: Handling event
wmEvent  type:1 / LEFTMOUSE, val:2 / RELEASE,
         prev_type:1 / LEFTMOUSE, prev_val:2 / RELEASE,
         shift:0, ctrl:0, alt:0, oskey:0, keymodifier:0, is_repeat:0,
         mouse:(1836,636), ascii:'', utf8:'', pointer:0x7fd10cc2b028
 tablet: active: 1, pressure 0.0000, tilt: (0.0000 0.0000)

Now, in bug https://developer.blender.org/T62565 it says that a fix was put in place for 2.83. As far as I can tell both 2.83 and 2.9 still exhibit this behavior.

So - the questions are:

Was this actually implemented/committed/rolled out?
How can I fix this so I can actually use my tablet?

Ok, looking around more I found this bug report: https://developer.blender.org/T62565 In it there is discussion of tablet pressure. So, I decided to run Blender 2.83.2 with `--debug-events` and see, and sure enough that does seem to be the issue. ``` wm_event_do_handlers: Handling event wmEvent type:1 / LEFTMOUSE, val:2 / RELEASE, prev_type:1 / LEFTMOUSE, prev_val:2 / RELEASE, shift:0, ctrl:0, alt:0, oskey:0, keymodifier:0, is_repeat:0, mouse:(1836,636), ascii:'', utf8:'', pointer:0x7fd10cc2b028 tablet: active: 1, pressure 0.0000, tilt: (0.0000 0.0000) ``` Now, in bug https://developer.blender.org/T62565 it says that a fix was put in place for 2.83. As far as I can tell both 2.83 and 2.9 still exhibit this behavior. So - the questions are: 1) Was this actually implemented/committed/rolled out? 2) How can I fix this so I can actually use my tablet?

Richard Antalik commented

2020-08-01 21:40:48 +02:00

Added subscribers: @PrototypeNM1, @iss

Richard Antalik commented

2020-08-01 21:40:48 +02:00

@PrototypeNM1 can you look at this?

Nicholas Rishel commented

2020-08-02 01:05:25 +02:00

Added subscriber: @ArtoKitula

Nicholas Rishel commented

2020-08-02 01:05:25 +02:00

@iss issue is macOS specific, unfortunately not my area. :(

Maybe an issue for @ArtoKitula?

@iss issue is macOS specific, unfortunately not my area. :( Maybe an issue for @ArtoKitula?

Phil Smy commented

2020-08-02 07:50:19 +02:00

More observations. I compiled my own version so I could add some debugging information and hard coded values to see what's going on.

In gpencil_paint.c in the gpencil_draw_apply_event method the event->tablet.pressure is always 0 when it comes from my tablets. If I hard-code in a value later by inserting this around line 2800

  if (p->pressure < 0.001f) {
    p->pressure = 0.75f;
    if (G.debug & G_DEBUG) {
      printf("GPencil - gpencil_draw_apply_event manually setting pressure: %.4f\n", p->pressure);
    }
  }

Then I get the debug string and I can actually draw! Of course the pressure never changes, but it is a step in the right direction.
Whatever is firing the event is not reading the pressure from my tablet. Could this be configuration on my side? Perhaps. But I did no configuration to get the pen to work in Photoshop, and the Pen Tablet tool reports varying pressure.

The other thing I have noticed, digging into this more, is that after trying to use the tablet, the debug messages will ALWAYS print out

tablet: active: 1 pressure: 0.0000

even if I go back to trying to draw with the mouse.
Perhaps this is expected behavior?

More observations. I compiled my own version so I could add some debugging information and hard coded values to see what's going on. In `gpencil_paint.c` in the `gpencil_draw_apply_event` method the `event->tablet.pressure` is always 0 when it comes from my tablets. If I hard-code in a value later by inserting this around line 2800 ``` if (p->pressure < 0.001f) { p->pressure = 0.75f; if (G.debug & G_DEBUG) { printf("GPencil - gpencil_draw_apply_event manually setting pressure: %.4f\n", p->pressure); } } ``` Then I get the debug string and I can actually draw! Of course the pressure never changes, but it is a step in the right direction. Whatever is firing the event is not reading the pressure from my tablet. Could this be configuration on my side? Perhaps. But I did no configuration to get the pen to work in Photoshop, and the Pen Tablet tool reports varying pressure. The other thing I have noticed, digging into this more, is that after trying to use the tablet, the debug messages will ALWAYS print out `tablet: active: 1 pressure: 0.0000` even if I go back to trying to draw with the mouse. Perhaps this is expected behavior?

Phil Smy commented

2020-08-02 08:01:25 +02:00

FYI - annotation_draw_invoke in annotate_paint.c DOES work and does get correct tablet pressure.

Today is the first day I am looking at the Blender code, so I am not confident I will find the source of the event information.

Sorry for the spam. Last comment on this, I promise.

FYI - `annotation_draw_invoke` in `annotate_paint.c` DOES work and does get correct tablet pressure. Today is the first day I am looking at the Blender code, so I am not confident I will find the source of the event information. Sorry for the spam. Last comment on this, I promise.

Pratik Borhade commented

2021-06-09 18:14:18 +02:00

Added subscriber: @PratikPB2123

Pratik Borhade commented

2021-06-09 18:14:18 +02:00

@philinjp , thanks for trying, just want to know if this is still an issue for you.

Please comment here if you want to share any update regarding this task. (I don't have device to test this, unfortunately)

@philinjp , thanks for trying, just want to know if this is still an issue for you. Please comment here if you want to share any update regarding this task. (I don't have device to test this, unfortunately)

Philipp Oeser commented

2022-02-25 14:25:48 +01:00

Added subscriber: @lichtwerk

Philipp Oeser commented

2022-02-25 14:25:48 +01:00

Changed status from 'Needs Triage' to: 'Needs User Info'

Philipp Oeser commented

2022-02-25 14:25:48 +01:00

A lot of time has passed since (and a lot of development/fixes, too).
@philinjp : could you check if you still have the problem in 3.1beta or 3.2alpha builds from https://builder.blender.org/download/daily/?

A lot of time has passed since (and a lot of development/fixes, too). @philinjp : could you check if you still have the problem in 3.1beta or 3.2alpha builds from https://builder.blender.org/download/daily/?

Philipp Oeser commented

2022-03-24 15:21:56 +01:00

Changed status from 'Needs User Info' to: 'Archived'

Philipp Oeser closed this issue

2022-03-24 15:21:56 +01:00

Philipp Oeser commented

2022-03-24 15:21:56 +01:00

No activity for more than a week. As per the tracker policy we assume the issue is gone and can be closed.

Thanks again for the report. If the problem persists please open a new report with the required information.

No activity for more than a week. As per the tracker policy we assume the issue is gone and can be closed. Thanks again for the report. If the problem persists please open a new report with the required information.

Sign in to join this conversation.

No Label

Download

What's New

Blender Studio

Manual

Developers Blog

Documentation

Benchmark

Blender Conference

Development Fund

One-time Donations

Tablet not drawing - moving pen causes drawing to break #79335