fidget_core/render/
config.rs

1//! Types used in configuration structures
2use std::sync::{
3    Arc,
4    atomic::{AtomicBool, Ordering},
5};
6
7/// Thread pool to use for multithreaded rendering
8///
9/// Most users will use the global Rayon pool, but it's possible to provide your
10/// own as well.
11pub enum ThreadPool {
12    /// User-provided pool
13    Custom(rayon::ThreadPool),
14    /// Global Rayon pool
15    Global,
16}
17
18impl ThreadPool {
19    /// Runs a function across the thread pool
20    pub fn run<F: FnOnce() -> V + Send, V: Send>(&self, f: F) -> V {
21        match self {
22            ThreadPool::Custom(p) => p.install(f),
23            ThreadPool::Global => f(),
24        }
25    }
26
27    /// Returns the number of threads in the pool
28    pub fn thread_count(&self) -> usize {
29        match self {
30            ThreadPool::Custom(p) => p.current_num_threads(),
31            ThreadPool::Global => rayon::current_num_threads(),
32        }
33    }
34}
35
36/// Token to cancel an in-progress operation
37#[derive(Clone, Default)]
38pub struct CancelToken(Arc<AtomicBool>);
39
40impl CancelToken {
41    /// Build a new token, which is initialize as "not cancelled"
42    pub fn new() -> Self {
43        Self::default()
44    }
45
46    /// Mark this token as cancelled
47    pub fn cancel(&self) {
48        self.0.store(true, Ordering::Relaxed);
49    }
50
51    /// Check if the token is cancelled
52    pub fn is_cancelled(&self) -> bool {
53        self.0.load(Ordering::Relaxed)
54    }
55
56    /// Returns a raw pointer to the inner flag
57    ///
58    /// This is used in shared memory environments where the `CancelToken`
59    /// itself cannot be passed between threads, i.e. to send a cancel token to
60    /// a web worker.
61    ///
62    /// To avoid a memory leak, the pointer must be converted back to a
63    /// `CancelToken` using [`CancelToken::from_raw`].  In the meantime, users
64    /// should refrain from writing to the raw pointer.
65    #[doc(hidden)]
66    pub fn into_raw(self) -> *const AtomicBool {
67        Arc::into_raw(self.0)
68    }
69
70    /// Reclaims a released cancel token pointer
71    ///
72    /// # Safety
73    /// The pointer must have been previously returned by a call to
74    /// [`CancelToken::into_raw`].
75    #[doc(hidden)]
76    pub unsafe fn from_raw(ptr: *const AtomicBool) -> Self {
77        let a = unsafe { Arc::from_raw(ptr) };
78        Self(a)
79    }
80}
fidget_core/render/config.rs

fidget_core/render/
config.rs
