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Diffstat (limited to 'wgpu/src/widget/canvas/layer/cache.rs')
-rw-r--r-- | wgpu/src/widget/canvas/layer/cache.rs | 120 |
1 files changed, 0 insertions, 120 deletions
diff --git a/wgpu/src/widget/canvas/layer/cache.rs b/wgpu/src/widget/canvas/layer/cache.rs deleted file mode 100644 index 4ecebb48..00000000 --- a/wgpu/src/widget/canvas/layer/cache.rs +++ /dev/null @@ -1,120 +0,0 @@ -use crate::{ - canvas::{Drawable, Frame, Layer}, - Primitive, -}; - -use iced_native::Size; -use std::{borrow::Borrow, cell::RefCell, marker::PhantomData, sync::Arc}; - -enum State { - Empty, - Filled { - bounds: Size, - primitive: Arc<Primitive>, - }, -} - -impl Default for State { - fn default() -> Self { - State::Empty - } -} -/// A simple cache that stores generated geometry to avoid recomputation. -/// -/// A [`Cache`] will not redraw its geometry unless the dimensions of its layer -/// change or it is explicitly cleared. -/// -/// [`Layer`]: ../trait.Layer.html -/// [`Cache`]: struct.Cache.html -#[derive(Debug, Default)] -pub struct Cache { - state: RefCell<State>, -} - -impl Cache { - /// Creates a new empty [`Cache`]. - /// - /// [`Cache`]: struct.Cache.html - pub fn new() -> Self { - Cache { - state: Default::default(), - } - } - - /// Clears the cache, forcing a redraw the next time it is used. - /// - /// [`Cached`]: struct.Cached.html - pub fn clear(&mut self) { - *self.state.borrow_mut() = State::Empty; - } - - /// Binds the [`Cache`] with some data, producing a [`Layer`] that can be - /// added to a [`Canvas`]. - /// - /// [`Cache`]: struct.Cache.html - /// [`Layer`]: ../trait.Layer.html - /// [`Canvas`]: ../../struct.Canvas.html - pub fn with<'a, T>( - &'a self, - input: impl Borrow<T> + std::fmt::Debug + 'a, - ) -> impl Layer + 'a - where - T: Drawable + std::fmt::Debug + 'a, - { - Bind { - cache: self, - input: input, - drawable: PhantomData, - } - } -} - -#[derive(Debug)] -struct Bind<'a, T: Drawable, I: Borrow<T> + 'a> { - cache: &'a Cache, - input: I, - drawable: PhantomData<T>, -} - -impl<'a, T, I> Layer for Bind<'a, T, I> -where - T: Drawable + std::fmt::Debug, - I: Borrow<T> + std::fmt::Debug + 'a, -{ - fn draw(&self, current_bounds: Size) -> Arc<Primitive> { - use std::ops::Deref; - - if let State::Filled { bounds, primitive } = - self.cache.state.borrow().deref() - { - if *bounds == current_bounds { - return primitive.clone(); - } - } - - let mut frame = Frame::new(current_bounds.width, current_bounds.height); - self.input.borrow().draw(&mut frame); - - let primitive = Arc::new(frame.into_primitive()); - - *self.cache.state.borrow_mut() = State::Filled { - bounds: current_bounds, - primitive: primitive.clone(), - }; - - primitive - } -} - -impl std::fmt::Debug for State { - fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { - match self { - State::Empty => write!(f, "Empty"), - State::Filled { primitive, bounds } => f - .debug_struct("Filled") - .field("primitive", primitive) - .field("bounds", bounds) - .finish(), - } - } -} |