Is there a quick way to toggle size/opacity control with pressure and also adjust spacing?

Hello, I am looking for lightweight drawing app to use on a crappy laptop while I am away from my main PC and photoshop on it. I am having a real struggle, so many cool features across everything I tried but every app just manages to fall flat on it’s face because of various reasons. Mypaint felt right though, especially because I am finally able to pan and zoom with keyboard + stylus buttons and have various popup menus when I need them. (you’d be suprised how many “powerful” apps fail to provide these simple things and make them customisable).

However I am really missing few things. In photoshop I am constantly adjusting my brush by toggling size and opacity control with pressure, I can do it by simply clicking buttons in the UI.

I noticed Painttool SAI seems to have similar feature as well
(can’t post a second image though)

I would also like to adjust the “spacing” of the brush. In other words, how quickly brush gets pasted onto canvas. Currently I feel it’s a little slow/far because quick strokes make really visible blobs rather than clean stroke. I think I am simply not finding it.

I’d be very thankful for help! :slightly_smiling:

There’s three settings you can look at in the Brush Settings Editor (Ctrl+B in MyPaint 1.2.0). Look under the Dabs foldout. “Dabbing” is how MyPaint’s brush engine describes plopping down a single drop/ellipse of paint onto the canvas.

Dabs per actual radius

The “actual” radius is what’s computed, so this allows finer strokes if a brush gets finer from velocity. here’s what 0.5 dabs per actual radius looks like for a brush that makes smaller dabs the faster you go:

Normally you’d use 2 or above, which works out pretty smooth.

Dabs per basic radius

The “base” radius is static, and can’t change from other dynamics. If you have a brush that changes the computed size of a blob from pressure or speed or tilt, then consider using “dabs per actual radius” instead.

Dabs per second

A bit less useful, but this might be what you describe above. If it’s a problem, I suggest making this zero, and using “dabs per actual radius” instead.

So does the pen-in-rings icon turn off ALL brush dynamics? I never use Photoshop or Painttool SAI myself, sorry to have to ask!

Brush dynamics are pretty fundamental to the way the MyPaint brush engine works, but you don’t have to make a particular output (e.g. dab size) respond to any inputs. If you do that, you get only the base value for the output, not the base value as modified by a bunch of varying inputs (e.g. speed/pressure/tilt).

The normal MyPaintish way of working is to make a new brush and then change the copy’s settings. The presets can be toggled between in your brush favourites.

But I hear what you’re saying. I’d quite like users to be able to override more, for example locking base radius to what’s in the options panel, or putting eraser and colourize override toggles there. If a way of implementing it cleanly could be found (say, a multiplier in the brush engine), it would be nice to present it in with the tool options as you describe.

Thank you for responses! It’ll definitively help.

In photoshop there are 2 icons which show a circle with a pen on top. One controls whether or not brush changes size on your pressure, and the other does the same with opacity. It’s extremely useful because no matter what brush you’re using, you can toggle these and don’t have to go deeper into the brush settings where you can customize brush dynamics based on speed, angle and so on.

With painttool SAI it’s like this from what I’ve seen:

With these toggles + quick access to brush size and hardnes (right click popup menu) it really creates a swift workflow where I can use a simple circular brush most of the time and just turn it into whatever I need on the go. The closest to that in mypaint would be to copy a brush, customize it a few times and save them?

Finally, is sharpness supposed to look so weird with low values? In PS it creates a nice soft brush when the value is low however in mypaint with most brushes it soften the edges but creates weird opaque core.

Are you aware of the “Reset this setting to default” option in brush settings? You don’t have to adjust a value or curve to disable opacity or size variation. For example I just selected classic/kabura, disabled opacity variation (Opacity->Opacity->Pressure) and then disabled radius variation (Basic->Radius->Pressure)

I’m not sure why you would save a variation brush when it’s pretty quick to just reset these settings or pick the brush you want off the canvas (with key W iirc).

If I can go slightly OT here, it might be good to change these existing ‘reset to default’ buttons to instead swap between default and non-default. In the case that the brush is already default in that aspect, the button would be a no-op (as it currently is). This would mean that the user could toggle any kind of variation easily, without worrying about destroying brush data.

On a more specific level, I guess these pSize / pOpacity toggles need to be implemented as BrushModifiers.
Specific settings that would be effected:

  • Basic → Radius → Pressure = 0
  • Basic → Radius by Random → Pressure = 0
  • Opacity → Opacity → Pressure = 0

(it’s unclear whether ‘Opacity multiply’ will ever be relevant here. Usually that’s used to prevent the brush from constantly drawing when the stylus isn’t touching the tablet.)

The only specific “objection” I have to what you’re proposing is that it should include keyboard shortcuts for each toggle – actually clicking on a small target is silly when you’re trying to work fast IMO.

(On the topic of shortcuts, maybe we should also have shortcuts cycling the ‘smooth’ parameter (‘Slow position tracking’ in actual fact) through values (0, 5, 10) – representing the generally useful categories of ‘no smoothing, moderate smoothing, heavy smoothing’.)