Drawing Tablet Lag Episode 3: Position Smoothing

[@dormin600]

the amount of valuable info in this video is shocking

[@thesevenpens]

Thank you so much for such a nice comment!

[@rudranilghosh2713]

This video deserves more attention

[@koyodraka]

There is something I want to contribute to the discussion about the Apple Pencil. I have the Pencil 2 and noticed that they calibrated the pen to activate before touching the screen by about 0.5 mm. That could be the reason why Apple doesn't want the device to display the exact pointer location on screen because that could make the pointer always tilted from the pen nibs. They heavily rely on prediction based on tilt, and since you can't turn off the tilt data for pressure sensitivity, which is normally managed by drawing software rather than hardware, the pressure curve isn't as good as it is on other tablets. (Note: My hypothesis could be incorrect.) I really enjoy your research on drawing tablets. You're doing really good work.

[@koyodraka]

I forgot to add this: Apple Pencils have 9-axis gyroscope sensors. That is why I think they heavily rely on of tilt data.

[@thesevenpens]

Very interesting! I have near hear that they did something before the pen touched the screen. What Could you elaborate on what "prediction based on tilt" means? It sounds like it's more than just compensating for the tilt to determine the tip position.

[@koyodraka]

@@thesevenpens Apple pencils (AES) and Samsung S-Pens (Wacom EMR) with batteries both have gyroscope sensors. The Surface Slim Pen 2 (AES) has an accelerometer. All of them have almost no pointer lag and zero force. Which could mean they use an extra censor to help predict where the line should be. I don't know the details, but in theory, you can use the Pythagorean theorem. Just like how they calculate the pen tilt, but with extra data by using the subtle movement of the pen to predict where the next point will be.

[@thesevenpens]

@@koyodrakaThank you so much for the clarification!

[@koyodraka]

@@thesevenpens Sorry, my mistake: the Surface Slim Pen 2 does not have an accelerometer. I guess it has a higher report rate than a normal stylus instead.

[@KiloGraham]

my guess as to pointer lag in apple products they may not use position smoothing and might depend entirely on raw data. my experience with drawing on an ipad air m1 with an apple pencil 1 was alot of "mechanical wave". Everything I drew was wiggly

[@thesevenpens]

With the apple pencil 1 did you see that wave when driving slowly or in general. With the apple pencil 2 I see the wave (what I call "diagonal wobble") with slow strokes.

[@Zalami84]

When I draw in both Krita and CSP there is zero space between my cursor and the mark I'm making. For some reason in Photoshop there is a very slight space/gap between my cursor and the mark I'm drawing that is more noticeable when putting long strokes down quickly. It feels like I have a minimal amount of smoothing turned on but I have that disabled in the brush settings and I'm also using opentabletdriver. The same thing happens when I use my mouse so it has nothing to do with my pen tablet. This also isn't a performance lag problem because every type of brush does this with the same minimal amount of spacing between cursor and the mark I'm drawing. Just curious if this is just how the Photoshop brush engine is or if this is a specific problem that I can fix?

[@thesevenpens]

And this is with opentabletdriver and photoshop right? I'll have to try this. I don't really draw with photoshop so I haven't noticed it. I could definitely believe it could be caused by the brush engine.

[@kei_kurono1]

Hi, great video ! Can you please make a tutorial on how to install OpenTabletDriver on a Wacom Intuos Pro Large ?

[@thesevenpens]

I wrote an extensive guide on installing OpenTabletDriver on windows here: docs.thesevenpens.com/drawtab/guides/drivers/opentabletdriver/opentabletdriver-windows

[@kei_kurono1]

@@thesevenpens Thank you so much !

[@kei_kurono1]

@@thesevenpens Is there a way to change pen pressure sensitivity inside Open Tablet Driver ?

[@thesevenpens]

@@kei_kurono1 There is! I just updated the doc above to link to some basic instructions. Here is the doc covering the pressure setup: docs.thesevenpens.com/drawtab/guides/drivers/opentabletdriver/opentabletdriver-pressure

[@kei_kurono1]

@@thesevenpens Thank you