Hi!
I'm using krita for the first time in a couple of years and I'm amazed at how much has changed and how polished it feels!

I'm trying to set the rotation of a rectangular brush (such as Chalk Grainy) to the Wacom art pen rotation, similar to the way Corel Painter uses it for the "Real" category of brushes.
So I open the brush options, check "Rotation" and uncheck "Drawing angle" and it works, except that I can only use 180 degrees of physical rotation (the graph is the default, a straight line from 0,-180 to 360,180).

Let's say the angle 0º is the pen buttons pointing to my left and 180º is the pen buttons pointing to my right:

• If I go from 0º to 180º clockwise the brush behaves as expected, no problem here and it feels great
• If I try to to from 0º to 180º counter clockwise the brush just won't rotate, it will stuck at 0º.
• When rotating clockwise, the moment I go more than 180º, the rotation will jump to 0º, I think, I'm not completely sure about the exact rotation, it just jumps and doesn't behave the way I'd expect to.

I'm not completely sure if this is a bug or is working as expected, since I'd like to have a total control of my pen rotation, the way I'd had in other software like painter and clip studio.

Using krita 4.2.6 in steam, Windows 10. On a cintiq13HD and intuos4 (the issue happens on both) with an art pen.

Thank you!

Hi, maybe you can use "tilt direction" and/or "tilt elevation" instead of "drawing angle".

mcoudert wrote:Hi, maybe you can use "tilt direction" and/or "tilt elevation" instead of "drawing angle".

Hi, thanks for the answer.

I could do that, but I'd like to use all the tools I have available, if possible. One of those tools is the art pen, which supports rotation. If I need to control the brush rotation using a grip or pro pens in a wacom tablet, tilt direction and/or elevation are definitely a good option.

Does the Tablet Tester log show stylus rotation? I don't know if it's supposed to and I don't have a tablet that has a stylus rotation output so that I can check if it does.

If it does, what do you get as you rotate the stylus through 0 - 360 degrees?

If you use stylus rotation as the control input to opacity for the basic_opacity brush (instead of pressure as input), do you get the full opacity range as you paint with the stylus while rotating it through 0-360 degrees?

ahabgreybeard wrote:Does the Tablet Tester log show stylus rotation? I don't know if it's supposed to and I don't have a tablet that has a stylus rotation output so that I can check if it does.

If it does, what do you get as you rotate the stylus through 0 - 360 degrees?

If you use stylus rotation as the control input to opacity for the basic_opacity brush (instead of pressure as input), do you get the full opacity range as you paint with the stylus while rotating it through 0-360 degrees?

Hi
1. the tablet settings window doesn't show rotation, only pressure, I don't know if there's a more direct way to test it.
2. I created a very simple brush and set the opacity to rotation and the results were very similar: at 180º the opacity is around 50% and between 180º and 360º the opacity goes to 0%

for test purposes I mapped the opacity curve to a straight line from 0º, 0% to 180º, 100%, and it paints fully opaque on 180º rotation, so the mapping seems to be working as intended.

I tested the pen in corel painter 2019 to discard hardware malfunction and it worked fine.

I'm not sure if Drawing Angle is what you're thinking it is. As far as I know, it's the type of sensor that works even with a mouse or a finger, it just calculates the drawing angle based on last few positions of the pen...

If you are looking for a sensor that checks the position of your pen and adjust the rotation (or other option) based on the angle it creates, Tilt Direction is what I think you're looking for. If you believe it's something else, could you please explain to me what is the difference between Tilt Direction and what you have in mind?

It is of course entirely possible that there is a bug in it (Drawing Angle), but it would be best if you attach some pictures to show what you mean.

Cheers

tymond wrote:could you please explain to me what is the difference between Tilt Direction and what you have in mind?

Hi
It's not drawing angle or direction, neither tilt.
It's a sensor available in some pens, like this one: https://us-store.wacom.com/Catalog/Accessories/Pens/art-pen#/undefined1%20 and allows you not only to tilt the pen but also rotate it.

If you want to use drawing angle, any pen will do, even a mouse
If you want to use tilt direction, you need an intuos pro and the pen that comes with it, usually a grip pen.
If you want to use rotation, you need an art pen or similar (and an intuos pro or cintiq), usually it's sold separately.

you can see here the brush options for rotation, you can see there are tilt direction/elevation and drawing angle options along the rotation options, which is selected:

The tablet settings window shows the adjustable pressure transfer curve so you can adjust the 'feel' of the stylus as you paint. Below that curve is a wide button that says 'Open Tablet Tester'. Is that the one you tried, that gives a log of tablet/stylus output as you draw on the test grid?

You said , "for test purposes I mapped the opacity curve to a straight line from 0º, 0% to 180º, 100%,....."
Shouldn't that be from 0º, 0% to 360º, 100%, as seems to be the case in the image you posted?

I've tried the Rotation parameter with every control input that I can use, Pressure, Drawing Angle, Distance, Time; they all give rotation of the full range of 0 - 360 degrees. (The transfer curve mapping claims that it's -180 to +180 degrees so I think a bug report is needed there for the UI aspect of it.)

With Wacom tablets, there is a thing you can try that often solves some behaviour problems. In the Wacom control/setup utility, you can set up a 'profile' for a specific application in case you want different behaviour in different applications. The Wacom drivers can sense which application is active. In the past, for some problems, the simple act of setting up a specific profile for krita has fixed some problems (it doesn't need to be any different from other profiles). You might want to try that to see if it helps.

EDIT: Additional thought: Does the tablet control utilty have an option to select stylus rotation output offset to give a choice of -180 -> +180 vs 0 -> 360 ?

ahabgreybeard wrote:The tablet settings window shows the adjustable pressure transfer curve so you can adjust the 'feel' of the stylus as you paint. Below that curve is a wide button that says 'Open Tablet Tester'. Is that the one you tried, that gives a log of tablet/stylus output as you draw on the test grid?

You said , "for test purposes I mapped the opacity curve to a straight line from 0º, 0% to 180º, 100%,....."
Shouldn't that be from 0º, 0% to 360º, 100%, as seems to be the case in the image you posted?

I've tried the Rotation parameter with every control input that I can use, Pressure, Drawing Angle, Distance, Time; they all give rotation of the full range of 0 - 360 degrees. (The transfer curve mapping claims that it's -180 to +180 degrees so I think a bug report is needed there for the UI aspect of it.)

With Wacom tablets, there is a thing you can try that often solves some behaviour problems. In the Wacom control/setup utility, you can set up a 'profile' for a specific application in case you want different behaviour in different applications. The Wacom drivers can sense which application is active. In the past, for some problems, the simple act of setting up a specific profile for krita has fixed some problems (it doesn't need to be any different from other profiles). You might want to try that to see if it helps.

EDIT: Additional thought: Does the tablet control utilty have an option to select stylus rotation output offset to give a choice of -180 -> +180 vs 0 -> 360 ?

1. Ohh, when you said tablet tester I thought you were refering to a wacom utility or something like that. I used it and it show X, Y, B(?) and P (Pressure, I assume). Doesn't display test info about tilt or barrel rotation
2. The image shows the default, The curve I was talking about looks like this:

3. tried the custom behavior, didn't work
4. nop, it has a custom curve only for pressure

This seems to be a bug, I wanted to check in the forums before creating the bug report.

re.1. In the tablet tester, 'B' is the Button output which indicates which tablet/stylus buttons are pressed.

re.2 That transfer curve you show in the image is not suitable for 'test purposes' if the control input (your stylus rotation output) varies from 0 to 360 because it doesn't give any change in opacity output over the range 180 -> 360.

When you said:
"2. I created a very simple brush and set the opacity to rotation and the results were very similar: at 180º the opacity is around 50% and between 180º and 360º the opacity goes to 0%"
Did that brush have a straight line transfer curve from 0/Transparent to 360/Opaque?
If it did then there is some kind of problem between your stylus and krita, assuming that your stylus does actually provide a 0-360 degree output for use by krita.
The details of that discussion would require a developer and/or someone who also has a stylus with rotation output.

(Thinking about it more, variation of the Size parameter would give a more obvious an easily observed comparison for testing against another parameter output.)

I've made a bug report about the rotation transfer graph output scale: https://bugs.kde.org/show_bug.cgi?id=412111 that I mentioned earlier.
The brush tip that I used is useful for showing rotation and you might want to try it for use in any bug report you make:
RotPointerBrush: https://www.dropbox.com/s/ytya5dz3aisil ... h.png?dl=0

Hi!
I'm having problem with the rotation range of my Wacom art pen, not getting full 360, and saw this thread and I'm wondering what's the status now?
edit - I'm using osx 10.14.6, and latest krita 4.3.0, and an Wacom Intous 4L with art pen, just upgraded Wacom driver to latest 6.3.39-1 but same thing

I've tried out the mapping from art pen to rotation in Krita and I'm getting this:

Art Pen:
gives 0-360 as output (realtime readings from Wacom diagnostic tool, pen buttons rotated to left is 360, to right is 180 and up gives 270)
output range 180-360, pen buttons away from me, is being used for rotation in krita (but seems to map to the values 0-180)
output range 0-180, pen buttons towards me, doesn't seem do anything in Krita

Krita:
I get full rotation of brush when setting x [0..180] -> y [-180..180]. That is I set the graph to: x=0 gives y=-180 and x>=180 gives y=180
(If I map x=180 to y=-180 and x=360 to y=180, there is no rotation at all)
With full rotation I mean that the brush can be rotated full range, by mapping only the half range of the art pen, so it's not a solution but it shows the problem with the mapping and reading of the art pens [0..180] span

So it seems art pen range 0-180 gives something out of range in krita, and art pen 180-360 maps to krita input (x-axis) 0-180