Hi, I think this might be an oversight: the wet paint/smudge tool doesn’t seem to sample on the first stamp with the flat setting, only after the number of stamps mix rate is set to. In the image attached at the top, you can see the wet brush only sampling after 19 stamps, the initial 19 being in the selected colour, unaffected by wetness settings or underlying colours. On the bottom, the smudge tool set to flat and a mix rate of 5 was dragged over the blue stroke, but only started doing anything after 5 stamps, thus ignoring blue and only picking up the 5th red stamp. Above it you can see the same brush with blur disabled working as expected from the first stamp.
Edit:
Another thing I just noticed is that full blend transparency might not be working as intended.
Namely, it behaves very differently with set opacity than with that same opacity achieved via pressure.
In the image, the top is what I’d expect to happen when sampling only the current layer, transparency of the opaque pixels is affected only when “dragged in” from the outside, as if transparency was a different colour, like the blue on the right of it. Both of these have the opacity set to 50%, and you can see the transparency is applied. Both of these also have minimum opacity in the dynamics panel set to 100%, though disabling opacity dynamics achieves the same result.
However, if the opacity dynamic is enabled and the minimum opacity setting set to below 100%, the smudge will set every pixel it touches to the opacity achieved by the pressure regardless of any other factor, like an a brush using the clear blending mode, only in reverse (ie where a brush using clear and 10% opacity would apply 10% transparency to the pixel, a smudge with full blend and current layer would SET the opacity of the pixel to 10%, but only if the opacity was above 10%).
In the image on the bottom is an example, smudge set to full blend transparency and minimum opacity of 50%, with the opacity dynamics enabled and using minimal pressure to get that 50% opacity, you can see it just sets the opacity to 50% even though there are no transparent pixels to inherit the transparency from.
I know this might be confusing to read, but if you make a new layer, fill it with any colour, set the smudge to full transparency and sampling the current layer, turn on opacity dynamics with minimum opacity set to let’s say 0% and apply that to the solid colour filled layer, you will see it acting almost like an eraser.
Now if you take the same brush, but disable opacity dynamics and set the opacity manually with the opacity slider, you will see it acting completely differently, as it will no longer act like an eraser even though there should be no mechanical difference.
Also, I’d again like to point out that the wetness settings are only accessible through brush settings, needing a minimum of 3 taps to access, and 4 if the brush is in the favourites menu, as you need to tap open the brush panel > … > edit this brush > wetness.
The settings cannot be found in the tool option panel, cannot be added to the side sliders, nor can “edit this brush” be added to the quick menu or the taskbar.
If you look at photoshop, you’ll see the relevant sliders at the top of the screen when using the equivalent tools. I understand screen economy is much stricter on an ipad, but there’s still the need to access these settings, perhaps a toggle to replace the flow/opacity slider with wetness when using the tools, like there is a 1px spacing toggle for the smudge tool, or adding the settings to the tool option panel when using the tools, like how sampling already is.
Spacing and softness are good candidates to be added to the tool panel as well, imo