Fix: Pygame Event Set Allowed Blocks Quit

A perf-tuning experiment uses set_allowed to filter to keyboard events; clicking the X button does nothing because QUIT isn’t allowed.

Always Allow QUIT

pygame.event.set_allowed([pygame.KEYDOWN, pygame.KEYUP, pygame.QUIT])

QUIT is the OS-driven close event. Drop it from the whitelist and the player can’t close the window.

Blocked Events Are Dropped

Blocked events never enter the queue. They’re not just hidden — they’re discarded. If you need them later, you must allow them and the queue resumes.

Use Filtering at Pump

For some workloads, leave all events allowed and filter in the dispatch loop. Costs a tiny CPU but no risk of dropping critical events.

Background Apps

FOCUS / WINDOW events also get dropped when blocked. If you handle pause-on-focus-lost, allow ACTIVEEVENT and the window-event family.

Verifying

Window close button works at all times. Set_allowed filters out high-volume events without breaking lifecycle.

“set_allowed is exclusive. Always include QUIT in the allow list.”

Default to never using set_allowed unless you measure event queue pressure — the surface area for bugs is large for a tiny perf win.