Trenchbroom: Texture angle controls behave strangely

[totalnewbie]

System Information

TrenchBroom Version 2020.1 Build v2020.1 Release Qt 5.9.5
Xubuntu 18.04

Description

(1) When I start a new TB session and edit a brush face for the first time, the up and down "Angle" buttons behave one way:

Clicking the up and down buttons without any modifiers increase and decrease the angle by increments of 1.
Scrolling the mousewheel without any modifiers while holding the cursor over the "Angle" number changes that number by increments of 1.
Holding down ctrl and clicking the buttons does nothing.
Holding down ctrl and scrolling the mousewheel while holding the cursor over the "Angle" number changes that number by increments of 4.

(2) When I edit a brush face again during the same session, the behaviour is different:

Clicking the up and down buttons without any modifiers increase and decrease the angle by increments of 15.
Scrolling the mousewheel without any modifiers while holding the cursor over the "Angle" number changes that number by increments of 15.
Holding down ctrl and clicking the buttons does nothing.
Holding down ctrl and scrolling the mousewheel while holding the cursor over the "Angle" number changes that number by increments of 1.

When I close the programme and re-open the same map file, the behaviour goes back to (1).

Edit:
Slight correction: the behaviour does not necessarily immediately change from (1) to (2). When I try to reproduce this in a test map, it seems to sometimes take a while of doing various things (drawing/moving/resizing brushes, etc.) for it to happen. Unfortunately I have not yet been able to figure out a pattern.

[totalnewbie]

@ericwa, as per our brief discussion on discord. Sorry it took a while for me to post this.

[kduske]

What about the offset and scale buttons, do they behave as expected? See the manual for what is considered the expected behavior.

[totalnewbie]

Ok, while testing this, the behaviour went from (1) to (2) after I changed the grid size.

When the Angle controls are behaving as described under (1) above:
Scale + no modifier and Scale + Shift work as expected.
Scale + Ctrl does nothing.
Offset + no modifier changes offset by increments of 1, despite grid size being 16 (as per the default setting).
Offset + Shift changes offset by increments of 2, despite grid size being 16.
Offset + Ctrl does nothing.

When the Angle controls are behaving as described under (2) above:
Scale + no modifier and Scale + Shift work as expected.
Scale + Ctrl does nothing.
Offset + no modifier works as expected.
Offset + Shift works as expected.
Offset + Ctrl does nothing.

I also tested Angle + Shift:

Under (1), Angle + Shift changes the angle in increments of 2.
Under (2), Angle + Shift works as expected.

[ericwa]

Part of this is fixed already (#3290), where the buttons step by 1 until you change the grid size, then they work normally. That'll be in the next release (2020.2).

About the Ctrl modifier, it sounds like Ctrl+Clicks are not reaching TrenchBroom at all. I'm guessing the Xubuntu window manager is intercepting them, maybe your "grab and move key" is set to Ctrl?
https://xubuntu.org/news/small-details-window-manager-shortcuts/

TB is incompatible with these window manager uses of modifiers, we really need full use of Ctrl, Alt, and Shift.

[ericwa]

@totalnewbie another thing to check, do other features that use Ctrl in TrenchBroom work? e.g. select a brush, Ctrl+Left click and drag it to drag a clone of it.

[totalnewbie]

@ericwa

I'm guessing the Xubuntu window manager is intercepting them, maybe your "grab and move key" is set to Ctrl?

Nope, it's set to Alt -- as per the default, which I've never changed.
(Thanks for that link, though. If I ever need or want to change that, now I know how.)

do other features that use Ctrl in TrenchBroom work? e.g. select a brush, Ctrl+Left click and drag it to drag a clone of it.

Yes, that works perfectly. Ctrl+Left click + drag creates and drags a clone.

Part of this is fixed already (#3290), where the buttons step by 1 until you change the grid size, then they work normally. That'll be in the next release (2020.2).

Thanks, that's good to know. :)

[totalnewbie]

Don't know if this is related, but adding it here in case it is somehow relevant or helpful: as I was working in TB just now, Alt + drag (to move brushes along the Z-axis) and Alt + arrow keys (to rotate brushes) suddenly stopped working. With Alt pressed, I couldn't move or rotate brushes at all. Had to restart TB.

Earlier today, I reassigned Xubuntu's "grab and move" function to the Super key, so Alt should no longer be used by the window manager at all.

[kduske]

I'll try to reproduce this in a VM.

[ericwa]

I can reproduce this - the problem is in SpinControl::stepBy.

The comment // QAbstractSpinBox spins by 10 steps if control is held is incorrect under Xubuntu (XFCE?). Ctrl+clicking on the up button causes SpinControl::stepBy to be called with steps=1, then we divide it by 10 giving 0.

Replacing the division by 10 with:

steps = (steps > 0) ? 1 : -1; // QAbstractSpinBox spins by 10 steps if control is held on some systems

fixes it

[eGax]

Yes the desktop environment is Xfce.