SUMMARY The value range for tangential pressure is halved regardless of curve settings when painting with a Wacom Airbrush pen. STEPS TO REPRODUCE Enable tangential pressure for any brush option (hue, value, etc) and paint using the pen wheel. OBSERVED RESULT The value range goes from 0 to 0.5 EXPECTED RESULT The value range should go from 0 to 1 SOFTWARE/OS VERSIONS Windows: Windows 10 Pro version 1903
Ok, so it looks like there is a little bug that mouse gets the value "0.0" instead of "0.5" like my tablet pen that doesn't support this type of pressure. However from the code, I cannot see how this bug is there. Qt's documentation: https://doc.qt.io/archives/qt-4.8/qtabletevent.html#tangentialPressure , so it returns a value in range (-1, 1) Then Krita in https://invent.kde.org/graphics/krita/-/blob/master/libs/flake/KoPointerEvent.cpp#L179 (KoPointerEvent::tangentialPressure()) returns a value: fmod( (x+1)/2 , 2), which is in range (0,1), with -1 => 0, 1 => 1. (0, being the neutral one, is converted to 0.5). However Qt's documentation says: "Current airbrushes can only move in the positive direction from the neutrual position." That could explain half of the range... but if it was the half (0.5,1.0), not (0,0.5).