style/
traversal_flags.rs

1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5//! Flags that control the traversal process.
6//!
7//! We CamelCase rather than UPPER_CASING so that we can grep for the same
8//! strings across gecko and servo.
9#![allow(non_upper_case_globals)]
10
11bitflags! {
12    /// Flags that control the traversal process.
13    #[derive(Clone, Copy, Debug, Eq, PartialEq)]
14    pub struct TraversalFlags: u32 {
15        /// Traverse only elements for animation restyles.
16        const AnimationOnly = 1 << 0;
17        /// Traverse and update all elements with CSS animations since
18        /// @keyframes rules may have changed. Triggered by CSS rule changes.
19        const ForCSSRuleChanges = 1 << 1;
20        /// The final animation-only traversal, which shouldn't really care about other
21        /// style changes anymore.
22        const FinalAnimationTraversal = 1 << 2;
23        /// Allows the traversal to run in parallel if there are sufficient cores on
24        /// the machine.
25        const ParallelTraversal = 1 << 7;
26        /// Flush throttled animations. By default, we only update throttled animations
27        /// when we have other non-throttled work to do. With this flag, we
28        /// unconditionally tick and process them.
29        const FlushThrottledAnimations = 1 << 8;
30
31    }
32}
33
34/// Asserts that all TraversalFlags flags have a matching ServoTraversalFlags value in gecko.
35#[cfg(feature = "gecko")]
36#[inline]
37pub fn assert_traversal_flags_match() {
38    use crate::gecko_bindings::structs;
39
40    macro_rules! check_traversal_flags {
41        ( $( $a:ident => $b:path ),*, ) => {
42            if cfg!(debug_assertions) {
43                let mut modes = TraversalFlags::all();
44                $(
45                    assert_eq!(structs::$a as usize, $b.bits() as usize, stringify!($b));
46                    modes.remove($b);
47                )*
48                assert_eq!(modes, TraversalFlags::empty(), "all TraversalFlags bits should have an assertion");
49            }
50        }
51    }
52
53    check_traversal_flags! {
54        ServoTraversalFlags_AnimationOnly => TraversalFlags::AnimationOnly,
55        ServoTraversalFlags_ForCSSRuleChanges => TraversalFlags::ForCSSRuleChanges,
56        ServoTraversalFlags_FinalAnimationTraversal => TraversalFlags::FinalAnimationTraversal,
57        ServoTraversalFlags_ParallelTraversal => TraversalFlags::ParallelTraversal,
58        ServoTraversalFlags_FlushThrottledAnimations => TraversalFlags::FlushThrottledAnimations,
59    }
60}
61
62impl TraversalFlags {
63    /// Returns true if the traversal is for animation-only restyles.
64    #[inline]
65    pub fn for_animation_only(&self) -> bool {
66        self.contains(TraversalFlags::AnimationOnly)
67    }
68}
style/traversal_flags.rs

style/
traversal_flags.rs
