Cache last used layer_id for StackingOrder

This optimizes rendering time by saving computation of the layer_id and
comparison when inserting it into the `BTreeMaps`.

Co-authored-by: Antonio <antonio@zed.dev>
This commit is contained in:
Thorsten Ball 2024-01-23 11:43:51 +01:00
parent 5a9f1e4eb7
commit bf843e2131

View file

@ -39,6 +39,7 @@ impl From<ViewId> for EntityId {
#[derive(Default)]
pub(crate) struct Scene {
last_layer: Option<(StackingOrder, LayerId)>,
layers_by_order: BTreeMap<StackingOrder, LayerId>,
orders_by_layer: BTreeMap<LayerId, StackingOrder>,
pub(crate) shadows: Vec<Shadow>,
@ -52,6 +53,7 @@ pub(crate) struct Scene {
impl Scene {
pub fn clear(&mut self) {
self.last_layer = None;
self.layers_by_order.clear();
self.orders_by_layer.clear();
self.shadows.clear();
@ -139,14 +141,22 @@ impl Scene {
}
fn layer_id_for_order(&mut self, order: &StackingOrder) -> LayerId {
if let Some(layer_id) = self.layers_by_order.get(order) {
if let Some((last_order, last_layer_id)) = self.last_layer.as_ref() {
if order == last_order {
return *last_layer_id;
}
}
let layer_id = if let Some(layer_id) = self.layers_by_order.get(order) {
*layer_id
} else {
let next_id = self.layers_by_order.len() as LayerId;
self.layers_by_order.insert(order.clone(), next_id);
self.orders_by_layer.insert(next_id, order.clone());
next_id
}
};
self.last_layer = Some((order.clone(), layer_id));
layer_id
}
pub fn reuse_views(&mut self, views: &FxHashSet<EntityId>, prev_scene: &mut Self) {