gallery/vendor/i-slint-core/lib.rs
Greg Pomerantz 2f4768f354 Fix 120Hz scroll jank end-to-end: render-ahead present + full-cache eviction off the UI thread
Three root causes, all fixed and verified on the Pixel 9 Pro:

1. Present phase (backend + renderer): VSYNC_LOCKED_RENDER defers the
   render to the vsync wake; RENDER_AHEAD presents the previous frame at
   the start of render() (phase = wake + ~1.1 ms) and holds the new
   frame one slot. Crash fix: a held wgpu frame must be PRESENTED, never
   merely dropped, before the next acquire (AlreadyAcquired panic at
   launch otherwise); discard_pending_frame presents too.

2. Full-res prefetch churn (src/lib.rs): the 8-slot full cache cycled
   through a ~20-cell viewport forever (137 decodes/20 s) and each
   eviction free()'d a 50 MB Vec on the UI thread (20-52 ms CPU spikes,
   ~7/s = the residual SLOWEV NonMain jank). Fix: 60 s tombstone
   cooldown on evicted paths (idle prefetch skips, urgent tap bypasses)
   + off-thread reaper for the freed blobs (insert: 21 ms -> 4 us).

3. (earlier) Skia final flush + Mailbox present mode (vendor, M3).

Instrumentation (all behind --features perf): OTHR/INVK/INVK_TAG/FLCK
lines for cross-thread closure timing and push-site tagging.

Warm measured swipe, 8580-file grid: cadence median 8.33 ms (exact
120 Hz), p99 15.5 ms, 5/552 gaps >16.7 ms (0.9%, max 28.3 ms, zero
>33 ms); PRES phase median ~994 us, zero late frames. Docs updated
(docs/BUGS/scroll-jank-120hz.md, full scorecard + line reference).

Also: vendored i-slint-core + wgpu-hal (vkshim interposition patch),
vkshim profiling tooling, backend made a non-optional dep, debuggable
flag for simpleperf (REMOVE before shipping).
2026-10-30 02:49:23 -04:00

195 lines
5.8 KiB
Rust

// Copyright © SixtyFPS GmbH <info@slint.dev>
// SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-Royalty-free-2.0 OR LicenseRef-Slint-Software-3.0
// cSpell: ignore sharedvector textlayout
#![doc = include_str!("README.md")]
#![doc(html_logo_url = "https://slint.dev/logo/slint-logo-square-light.svg")]
#![cfg_attr(docsrs, feature(doc_cfg))]
#![deny(unsafe_code)]
#![allow(clippy::missing_safety_doc)] // FFI surface has many exported unsafe entry points
#![cfg_attr(slint_nightly_test, feature(non_exhaustive_omitted_patterns_lint))]
#![cfg_attr(slint_nightly_test, warn(non_exhaustive_omitted_patterns))]
#![no_std]
#![debugger_visualizer(gdb_script_file = "gdb_pretty_printers.py")]
extern crate alloc;
#[cfg(feature = "std")]
extern crate std;
#[cfg(all(not(feature = "std"), feature = "unsafe-single-threaded"))]
pub mod unsafe_single_threaded;
#[cfg(all(not(feature = "std"), not(feature = "unsafe-single-threaded")))]
compile_error!(
"At least one of the following feature need to be enabled: `std` or `unsafe-single-threaded`"
);
pub use crate::items::OperatingSystemType;
#[cfg(all(not(feature = "std"), feature = "unsafe-single-threaded"))]
pub use crate::unsafe_single_threaded::thread_local;
#[cfg(feature = "std")]
pub use std::thread_local;
pub mod accessibility;
pub mod animations;
pub mod api;
pub mod callbacks;
pub mod component_factory;
pub mod context;
pub mod cursor;
pub mod data_transfer;
pub mod date_time;
pub mod debug_log;
pub mod future;
pub mod graphics;
pub mod input;
pub mod item_focus;
pub mod item_rendering;
pub mod item_tree;
pub mod items;
pub mod layout;
pub mod lengths;
pub mod menus;
pub mod model;
pub mod partial_renderer;
pub mod platform;
pub mod properties;
pub mod renderer;
#[cfg(feature = "rtti")]
pub mod rtti;
pub mod sharedvector;
pub mod slice;
pub mod string;
pub mod styled_text;
pub mod textlayout;
pub mod timers;
pub mod translations;
pub mod window;
#[doc(inline)]
pub use string::SharedString;
#[doc(inline)]
pub use sharedvector::SharedVector;
#[doc(inline)]
pub use graphics::{ImageInner, StaticTextures};
#[doc(inline)]
pub use properties::Property;
#[doc(inline)]
pub use callbacks::Callback;
#[doc(inline)]
pub use graphics::Color;
#[doc(inline)]
pub use graphics::Brush;
#[doc(inline)]
pub use graphics::RgbaColor;
#[cfg(feature = "std")]
#[doc(inline)]
pub use graphics::PathData;
#[doc(inline)]
pub use graphics::BorderRadius;
#[doc(inline)]
pub use data_transfer::DataTransfer;
pub use context::{SlintContext, SlintContextWeak, with_global_context};
#[cfg(not(slint_int_coord))]
pub type Coord = f32;
#[cfg(slint_int_coord)]
pub type Coord = i32;
/// This type is not exported from the public API crate, so function having this
/// parameter cannot be called from the public API without naming it
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub struct InternalToken;
#[cfg(feature = "std")]
thread_local!(
/// Permit testing code to force an OS type
pub static OPERATING_SYSTEM_OVERRIDE: core::cell::Cell<Option<OperatingSystemType>> =
Default::default();
);
#[cfg(not(target_family = "wasm"))]
pub fn detect_operating_system() -> OperatingSystemType {
#[cfg(feature = "std")]
if let Some(os_override) = OPERATING_SYSTEM_OVERRIDE.with(|os_override| os_override.get()) {
return os_override;
}
if cfg!(target_os = "android") {
OperatingSystemType::Android
} else if cfg!(target_os = "ios") {
OperatingSystemType::Ios
} else if cfg!(target_os = "macos") {
OperatingSystemType::Macos
} else if cfg!(target_os = "windows") {
OperatingSystemType::Windows
} else if cfg!(target_os = "linux") {
OperatingSystemType::Linux
} else {
OperatingSystemType::Other
}
}
#[cfg(target_family = "wasm")]
pub fn detect_operating_system() -> OperatingSystemType {
if let Some(os_override) = OPERATING_SYSTEM_OVERRIDE.with(|os_override| os_override.get()) {
return os_override;
}
// Querying the navigator involves a round-trip to JavaScript and some string processing, so
// cache the result: it cannot change for the lifetime of the page.
static DETECTED: std::sync::LazyLock<OperatingSystemType> = std::sync::LazyLock::new(|| {
let mut user_agent =
web_sys::window().and_then(|w| w.navigator().user_agent().ok()).unwrap_or_default();
user_agent.make_ascii_lowercase();
let mut platform =
web_sys::window().and_then(|w| w.navigator().platform().ok()).unwrap_or_default();
platform.make_ascii_lowercase();
if user_agent.contains("ipad") || user_agent.contains("iphone") {
OperatingSystemType::Ios
} else if user_agent.contains("android") {
OperatingSystemType::Android
} else if platform.starts_with("mac") {
OperatingSystemType::Macos
} else if platform.starts_with("win") {
OperatingSystemType::Windows
} else if platform.starts_with("linux") {
OperatingSystemType::Linux
} else {
OperatingSystemType::Other
}
});
*DETECTED
}
/// Returns true if the current platform is an Apple platform (macOS, iOS, iPadOS)
pub fn is_apple_platform() -> bool {
matches!(detect_operating_system(), OperatingSystemType::Macos | OperatingSystemType::Ios)
}
pub fn open_url(url: &str, window: &crate::api::Window) -> Result<(), crate::api::PlatformError> {
crate::window::WindowInner::from_pub(window).context().platform().open_url(url)
}
#[cfg(target_os = "macos")]
pub fn macos_bring_all_windows_to_front() {
use objc2::MainThreadMarker;
use objc2_app_kit::NSApplication;
let Some(mtm) = MainThreadMarker::new() else { return };
NSApplication::sharedApplication(mtm).arrangeInFront(None);
}
#[cfg(not(target_os = "macos"))]
pub fn macos_bring_all_windows_to_front() {}