use crate::{
render_resource::{Texture, TextureView},
renderer::RenderDevice,
};
use bevy_ecs::{prelude::ResMut, system::Resource};
use bevy_utils::{Entry, HashMap};
use wgpu::{TextureDescriptor, TextureViewDescriptor};
struct CachedTextureMeta {
texture: Texture,
default_view: TextureView,
taken: bool,
frames_since_last_use: usize,
}
#[derive(Clone)]
pub struct CachedTexture {
pub texture: Texture,
pub default_view: TextureView,
}
#[derive(Resource, Default)]
pub struct TextureCache {
textures: HashMap<TextureDescriptor<'static>, Vec<CachedTextureMeta>>,
}
impl TextureCache {
pub fn get(
&mut self,
render_device: &RenderDevice,
descriptor: TextureDescriptor<'static>,
) -> CachedTexture {
match self.textures.entry(descriptor) {
Entry::Occupied(mut entry) => {
for texture in entry.get_mut().iter_mut() {
if !texture.taken {
texture.frames_since_last_use = 0;
texture.taken = true;
return CachedTexture {
texture: texture.texture.clone(),
default_view: texture.default_view.clone(),
};
}
}
let texture = render_device.create_texture(&entry.key().clone());
let default_view = texture.create_view(&TextureViewDescriptor::default());
entry.get_mut().push(CachedTextureMeta {
texture: texture.clone(),
default_view: default_view.clone(),
frames_since_last_use: 0,
taken: true,
});
CachedTexture {
texture,
default_view,
}
}
Entry::Vacant(entry) => {
let texture = render_device.create_texture(entry.key());
let default_view = texture.create_view(&TextureViewDescriptor::default());
entry.insert(vec![CachedTextureMeta {
texture: texture.clone(),
default_view: default_view.clone(),
taken: true,
frames_since_last_use: 0,
}]);
CachedTexture {
texture,
default_view,
}
}
}
}
pub fn is_empty(&self) -> bool {
self.textures.is_empty()
}
pub fn update(&mut self) {
self.textures.retain(|_, textures| {
for texture in textures.iter_mut() {
texture.frames_since_last_use += 1;
texture.taken = false;
}
textures.retain(|texture| texture.frames_since_last_use < 3);
!textures.is_empty()
});
}
}
pub fn update_texture_cache_system(mut texture_cache: ResMut<TextureCache>) {
texture_cache.update();
}