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-rw-r--r--wgpu/src/widget/canvas/layer.rs80
1 files changed, 4 insertions, 76 deletions
diff --git a/wgpu/src/widget/canvas/layer.rs b/wgpu/src/widget/canvas/layer.rs
index c239a254..8c069f18 100644
--- a/wgpu/src/widget/canvas/layer.rs
+++ b/wgpu/src/widget/canvas/layer.rs
@@ -1,88 +1,16 @@
+mod cached;
+
+pub use cached::Cached;
+
use crate::{canvas::Frame, triangle};
use iced_native::Size;
-use std::cell::RefCell;
use std::sync::Arc;
pub trait Layer: std::fmt::Debug {
fn draw(&self, bounds: Size) -> Arc<triangle::Mesh2D>;
}
-use std::marker::PhantomData;
-
-#[derive(Debug)]
-pub struct Cached<T: Drawable> {
- input: PhantomData<T>,
- cache: RefCell<Cache>,
-}
-
-#[derive(Debug)]
-enum Cache {
- Empty,
- Filled {
- mesh: Arc<triangle::Mesh2D>,
- bounds: Size,
- },
-}
-
-impl<T> Cached<T>
-where
- T: Drawable + std::fmt::Debug,
-{
- pub fn new() -> Self {
- Cached {
- input: PhantomData,
- cache: RefCell::new(Cache::Empty),
- }
- }
-
- pub fn clear(&mut self) {
- *self.cache.borrow_mut() = Cache::Empty;
- }
-
- pub fn with<'a>(&'a self, input: &'a T) -> impl Layer + 'a {
- Bind {
- layer: self,
- input: input,
- }
- }
-}
-
-#[derive(Debug)]
-struct Bind<'a, T: Drawable> {
- layer: &'a Cached<T>,
- input: &'a T,
-}
-
-impl<'a, T> Layer for Bind<'a, T>
-where
- T: Drawable + std::fmt::Debug,
-{
- fn draw(&self, current_bounds: Size) -> Arc<triangle::Mesh2D> {
- use std::ops::Deref;
-
- if let Cache::Filled { mesh, bounds } =
- self.layer.cache.borrow().deref()
- {
- if *bounds == current_bounds {
- return mesh.clone();
- }
- }
-
- let mut frame = Frame::new(current_bounds.width, current_bounds.height);
- self.input.draw(&mut frame);
-
- let mesh = Arc::new(frame.into_mesh());
-
- *self.layer.cache.borrow_mut() = Cache::Filled {
- mesh: mesh.clone(),
- bounds: current_bounds,
- };
-
- mesh
- }
-}
-
pub trait Drawable {
fn draw(&self, frame: &mut Frame);
}