use crate::{
render_resource::{encase::internal::WriteInto, DynamicUniformBuffer, ShaderType},
renderer::{RenderDevice, RenderQueue},
view::ComputedVisibility,
Extract, ExtractSchedule, Render, RenderApp, RenderSet,
};
use bevy_app::{App, Plugin};
use bevy_asset::{Asset, Handle};
use bevy_ecs::{
component::Component,
prelude::*,
query::{QueryItem, ReadOnlyWorldQuery, WorldQuery},
system::lifetimeless::Read,
};
use std::{marker::PhantomData, ops::Deref};
pub use bevy_render_macros::ExtractComponent;
#[derive(Component)]
pub struct DynamicUniformIndex<C: Component> {
index: u32,
marker: PhantomData<C>,
}
impl<C: Component> DynamicUniformIndex<C> {
#[inline]
pub fn index(&self) -> u32 {
self.index
}
}
pub trait ExtractComponent: Component {
type Query: WorldQuery + ReadOnlyWorldQuery;
type Filter: WorldQuery + ReadOnlyWorldQuery;
type Out: Bundle;
fn extract_component(item: QueryItem<'_, Self::Query>) -> Option<Self::Out>;
}
pub struct UniformComponentPlugin<C>(PhantomData<fn() -> C>);
impl<C> Default for UniformComponentPlugin<C> {
fn default() -> Self {
Self(PhantomData)
}
}
impl<C: Component + ShaderType + WriteInto + Clone> Plugin for UniformComponentPlugin<C> {
fn build(&self, app: &mut App) {
if let Ok(render_app) = app.get_sub_app_mut(RenderApp) {
render_app
.insert_resource(ComponentUniforms::<C>::default())
.add_systems(
Render,
prepare_uniform_components::<C>.in_set(RenderSet::Prepare),
);
}
}
}
#[derive(Resource)]
pub struct ComponentUniforms<C: Component + ShaderType> {
uniforms: DynamicUniformBuffer<C>,
}
impl<C: Component + ShaderType> Deref for ComponentUniforms<C> {
type Target = DynamicUniformBuffer<C>;
#[inline]
fn deref(&self) -> &Self::Target {
&self.uniforms
}
}
impl<C: Component + ShaderType> ComponentUniforms<C> {
#[inline]
pub fn uniforms(&self) -> &DynamicUniformBuffer<C> {
&self.uniforms
}
}
impl<C: Component + ShaderType> Default for ComponentUniforms<C> {
fn default() -> Self {
Self {
uniforms: Default::default(),
}
}
}
fn prepare_uniform_components<C: Component>(
mut commands: Commands,
render_device: Res<RenderDevice>,
render_queue: Res<RenderQueue>,
mut component_uniforms: ResMut<ComponentUniforms<C>>,
components: Query<(Entity, &C)>,
) where
C: ShaderType + WriteInto + Clone,
{
component_uniforms.uniforms.clear();
let entities = components
.iter()
.map(|(entity, component)| {
(
entity,
DynamicUniformIndex::<C> {
index: component_uniforms.uniforms.push(component.clone()),
marker: PhantomData,
},
)
})
.collect::<Vec<_>>();
commands.insert_or_spawn_batch(entities);
component_uniforms
.uniforms
.write_buffer(&render_device, &render_queue);
}
pub struct ExtractComponentPlugin<C, F = ()> {
only_extract_visible: bool,
marker: PhantomData<fn() -> (C, F)>,
}
impl<C, F> Default for ExtractComponentPlugin<C, F> {
fn default() -> Self {
Self {
only_extract_visible: false,
marker: PhantomData,
}
}
}
impl<C, F> ExtractComponentPlugin<C, F> {
pub fn extract_visible() -> Self {
Self {
only_extract_visible: true,
marker: PhantomData,
}
}
}
impl<C: ExtractComponent> Plugin for ExtractComponentPlugin<C> {
fn build(&self, app: &mut App) {
if let Ok(render_app) = app.get_sub_app_mut(RenderApp) {
if self.only_extract_visible {
render_app.add_systems(ExtractSchedule, extract_visible_components::<C>);
} else {
render_app.add_systems(ExtractSchedule, extract_components::<C>);
}
}
}
}
impl<T: Asset> ExtractComponent for Handle<T> {
type Query = Read<Handle<T>>;
type Filter = ();
type Out = Handle<T>;
#[inline]
fn extract_component(handle: QueryItem<'_, Self::Query>) -> Option<Self::Out> {
Some(handle.clone_weak())
}
}
fn extract_components<C: ExtractComponent>(
mut commands: Commands,
mut previous_len: Local<usize>,
query: Extract<Query<(Entity, C::Query), C::Filter>>,
) {
let mut values = Vec::with_capacity(*previous_len);
for (entity, query_item) in &query {
if let Some(component) = C::extract_component(query_item) {
values.push((entity, component));
}
}
*previous_len = values.len();
commands.insert_or_spawn_batch(values);
}
fn extract_visible_components<C: ExtractComponent>(
mut commands: Commands,
mut previous_len: Local<usize>,
query: Extract<Query<(Entity, &ComputedVisibility, C::Query), C::Filter>>,
) {
let mut values = Vec::with_capacity(*previous_len);
for (entity, computed_visibility, query_item) in &query {
if computed_visibility.is_visible() {
if let Some(component) = C::extract_component(query_item) {
values.push((entity, component));
}
}
}
*previous_len = values.len();
commands.insert_or_spawn_batch(values);
}