spacr.qt.widgets.popup_state

Whether a menu or a tooltip is currently on screen.

WHY THIS EXISTS. Opening the spaCR menu cost a burst of ~105 widget repaints over the live GL backdrop – 68 QLabel, 25 QWidget, 12 AppTile – and a tooltip did the same. That burst is the compositor re-composing a popup over a native GL child, and it is what the user sees as the dock and the header flickering.

The backdrop cannot stop the popup from compositing, but it can stop being a moving target while it happens. Holding the animation still for the moment a popup is up takes the menu from 238 painted widgets to 5, and a tooltip from 90 to 0.

WHY IT IS A POLL AND NOT AN EVENT FILTER. The obvious implementation is an application-wide event filter watching for Show and Hide on popup windows. That was written, measured, and thrown away: it ran Python for every event in the application – 13,646 calls per second while a module opens – and it cost 130 ms on the very GUI-thread block that opening a module had just been fixed to shorten (1380-1424 ms became 1473-1606).

Qt already knows the answer and will give it for two C++ calls, so the animation asks once per frame instead. At sixty frames a second that is 120 calls, against thirteen thousand.

Functions

a_popup_is_on_screen(→ bool)

True while a menu or a tooltip is showing, anywhere in the app.

Module Contents

spacr.qt.widgets.popup_state.a_popup_is_on_screen() → bool

True while a menu or a tooltip is showing, anywhere in the app.

Both are asked for, because they are different things to Qt: a menu is an activePopupWidget (window type Qt::Popup), and a tooltip is not – it is its own Qt::ToolTip window that QToolTip tracks separately. Watching only the first would have left the tooltip flicker exactly as it was, and that was reported alongside the menu.

Never raises. This is called from an animation tick, so a failure here must cost a frame’s decision at worst, not the backdrop: an unanswerable question is answered “no popup”, which is the behaviour the application had before this existed.