When using mouse draw on touchscreen, it goes along with clicking+dragging on touchscreen. To my mind it would be more correct to disable mouse clicks while drawing (ie. after pressing the default shortcut meta+shift). Reproducible: Always Steps to Reproduce: 1. Press and hold the shortcut of mouse draw (meta+shift by default) 2. Start drawing on touch screen Actual Results: Mouse click + drag happens on touching the screen. Expected Results: No clicks should happen while drawing.
I don't think we are able to detect whether the click comes from a touch screen or from a normal pointer device. All we get is that it is a pointer event, the actual device is hidden from KWin (30 years ago there were only mice). With Wayland this might become possible as there are touch events. We'll have to see. (I don't have a touch device, so it needs someone else to implement it).
OK, but should even the mouse click work while drawing? Or what about a simple checkbox-setting for disabling all the mouse clicks while drawing?
*cough* https://git.reviewboard.kde.org/r/103022/ No, that patch will certainly no longer apply cleanly - and it's too late for adding it to KDE SC 4. The effect is designed to leave a trace when holding Meta+Shift, that's all. When you touch the touchscreen start usually causes a mousepress event, the "click" on release is expectable (depending on the client at that position, usually press and release have to be on the same item or even "nearby") For at least a touchscreen environment the effect should however be altered to eg. on shortcut triger add a canvas overlay where you can paint around - this could be extended to add brush and color selections etc. ie. some sort of "MS Paint your Desktop"
I'm changing to feature request as there's not really a bug in the current behavior.
Since it's kwin is wayland only, this should no longer be an issue. Touch events use different code path on wayland.