# Objective

I am building an [app](https://github.com/nolight132/sonora) with GPUI,
and the current animation throttling implementation does not quite meet
its requirements. I needed the window to stay at a smooth framerate when
unfocused to display lyrics, which was not possible at the time without
modifying GPUI’s frame scheduling behavior. I understand that this is
not a problem for Zed, but I believe making this behavior a field in
`WindowOptions` could be beneficial for other programs going forward.

## Solution

Added a field to `WindowOptions` struct which controls the minimum
interval between animation frames while the window is inactive
(documented). Kept the default value GPUI currently uses.

## Testing

- Ran `gpui/src/examples/animation.rs` with different presets - works as
expected. Zed compiles. One thing worth noting: this setting does not
guarantee the window refreshes at this exact interval, as frames are
still paced by the compositor. For granular FPS control, a helper
function is needed. I have decided to keep it simple and use the
existing logic.
- Tested on NixOS x86_64, Niri.

## Self-Review Checklist:

- [x] I've reviewed my own diff for quality, security, and reliability
- [x] Unsafe blocks (if any) have justifying comments
- [x] The content adheres to Zed's UI standards
([UX/UI](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
and
[icon](https://github.com/zed-industries/zed/blob/main/crates/icons/README.md)
guidelines)
- [ ] Tests cover the new/changed behavior (the default didn't change,
tests still pass)
- [x] Performance impact has been considered and is acceptable (no
performance impact unless explicitly set)

## Showcase

Before (unfocused):
<img width="1280" height="802" alt="image"
src="https://github.com/user-attachments/assets/e3302c1d-4f4a-4503-96a2-0bf24e28096c"
/>

After (unfocused with `inactive_frame_interval` set to 16ms):
<img width="1450" height="972" alt="image"
src="https://github.com/user-attachments/assets/1183adf1-2da1-42d5-8e97-f4ad7a31b783"
/>

---

Release Notes:

- Added `WindowOptions::inactive_frame_interval` for configuring
animation frame throttling on inactive GPUI windows.