Clean up 2d render phases (#12982)

# Objective

Currently, the 2d pipeline only has a transparent pass that is used for
everything. I want to have separate passes for opaque/alpha
mask/transparent meshes just like in 3d.

This PR does the basic work to start adding new phases to the 2d
pipeline and get the current setup a bit closer to 3d.

## Solution

- Use `ViewNode` for `MainTransparentPass2dNode`
- Added `Node2d::StartMainPass`, `Node2d::EndMainPass`
- Rename everything to clarify that the main pass is currently the
transparent pass

---

## Changelog

- Added `Node2d::StartMainPass`, `Node2d::EndMainPass`

## Migration Guide

If you were using `Node2d::MainPass` to order your own custom render
node. You now need to order it relative to `Node2d::StartMainPass` or
`Node2d::EndMainPass`.

crates/bevy_core_pipeline/src/bloom/mod.rs

@@ -81,7 +81,7 @@ impl Plugin for BloomPlugin {
             .add_render_graph_node::<ViewNodeRunner<BloomNode>>(Core2d, Node2d::Bloom)
             .add_render_graph_edges(
                 Core2d,
-                (Node2d::MainPass, Node2d::Bloom, Node2d::Tonemapping),
+                (Node2d::EndMainPass, Node2d::Bloom, Node2d::Tonemapping),
             );
     }
 

crates/bevy_core_pipeline/src/core_2d/main_transparent_pass_2d_node.rs

@@ -3,67 +3,49 @@ use bevy_ecs::prelude::*;
 use bevy_render::{
     camera::ExtractedCamera,
     diagnostic::RecordDiagnostics,
-    render_graph::{Node, NodeRunError, RenderGraphContext},
+    render_graph::{NodeRunError, RenderGraphContext, ViewNode},
     render_phase::SortedRenderPhase,
     render_resource::RenderPassDescriptor,
     renderer::RenderContext,
-    view::{ExtractedView, ViewTarget},
+    view::ViewTarget,
 };
 #[cfg(feature = "trace")]
 use bevy_utils::tracing::info_span;
 
-pub struct MainPass2dNode {
-    query: QueryState<
-        (
-            &'static ExtractedCamera,
-            &'static SortedRenderPhase<Transparent2d>,
-            &'static ViewTarget,
-        ),
-        With<ExtractedView>,
-    >,
-}
+#[derive(Default)]
+pub struct MainTransparentPass2dNode {}
 
-impl FromWorld for MainPass2dNode {
-    fn from_world(world: &mut World) -> Self {
-        Self {
-            query: world.query_filtered(),
-        }
-    }
-}
+impl ViewNode for MainTransparentPass2dNode {
+    type ViewQuery = (
+        &'static ExtractedCamera,
+        &'static SortedRenderPhase<Transparent2d>,
+        &'static ViewTarget,
+    );
 
-impl Node for MainPass2dNode {
-    fn update(&mut self, world: &mut World) {
-        self.query.update_archetypes(world);
-    }
-
-    fn run(
+    fn run<'w>(
         &self,
         graph: &mut RenderGraphContext,
-        render_context: &mut RenderContext,
-        world: &World,
+        render_context: &mut RenderContext<'w>,
+        (camera, transparent_phase, target): bevy_ecs::query::QueryItem<'w, Self::ViewQuery>,
+        world: &'w World,
     ) -> Result<(), NodeRunError> {
         let view_entity = graph.view_entity();
-        let Ok((camera, transparent_phase, target)) = self.query.get_manual(world, view_entity)
-        else {
-            // no target
-            return Ok(());
-        };
 
-        {
+        if !transparent_phase.items.is_empty() {
             #[cfg(feature = "trace")]
-            let _main_pass_2d = info_span!("main_pass_2d").entered();
+            let _main_pass_2d = info_span!("main_transparent_pass_2d").entered();
 
             let diagnostics = render_context.diagnostic_recorder();
 
             let mut render_pass = render_context.begin_tracked_render_pass(RenderPassDescriptor {
-                label: Some("main_pass_2d"),
+                label: Some("main_transparent_pass_2d"),
                 color_attachments: &[Some(target.get_color_attachment())],
                 depth_stencil_attachment: None,
                 timestamp_writes: None,
                 occlusion_query_set: None,
             });
 
-            let pass_span = diagnostics.pass_span(&mut render_pass, "main_pass_2d");
+            let pass_span = diagnostics.pass_span(&mut render_pass, "main_transparent_pass_2d");
 
             if let Some(viewport) = camera.viewport.as_ref() {
                 render_pass.set_camera_viewport(viewport);

crates/bevy_core_pipeline/src/core_2d/mod.rs

@@ -1,5 +1,5 @@
 mod camera_2d;
-mod main_pass_2d_node;
+mod main_transparent_pass_2d_node;
 
 pub mod graph {
     use bevy_render::render_graph::{RenderLabel, RenderSubGraph};
@@ -14,7 +14,9 @@ pub mod graph {
     #[derive(Debug, Hash, PartialEq, Eq, Clone, RenderLabel)]
     pub enum Node2d {
         MsaaWriteback,
-        MainPass,
+        StartMainPass,
+        MainTransparentPass,
+        EndMainPass,
         Bloom,
         Tonemapping,
         Fxaa,
@@ -27,7 +29,7 @@ pub mod graph {
 use std::ops::Range;
 
 pub use camera_2d::*;
-pub use main_pass_2d_node::*;
+pub use main_transparent_pass_2d_node::*;
 
 use bevy_app::{App, Plugin};
 use bevy_ecs::prelude::*;
@@ -68,14 +70,21 @@ impl Plugin for Core2dPlugin {
 
         render_app
             .add_render_sub_graph(Core2d)
-            .add_render_graph_node::<MainPass2dNode>(Core2d, Node2d::MainPass)
+            .add_render_graph_node::<EmptyNode>(Core2d, Node2d::StartMainPass)
+            .add_render_graph_node::<ViewNodeRunner<MainTransparentPass2dNode>>(
+                Core2d,
+                Node2d::MainTransparentPass,
+            )
+            .add_render_graph_node::<EmptyNode>(Core2d, Node2d::EndMainPass)
             .add_render_graph_node::<ViewNodeRunner<TonemappingNode>>(Core2d, Node2d::Tonemapping)
             .add_render_graph_node::<EmptyNode>(Core2d, Node2d::EndMainPassPostProcessing)
             .add_render_graph_node::<ViewNodeRunner<UpscalingNode>>(Core2d, Node2d::Upscaling)
             .add_render_graph_edges(
                 Core2d,
                 (
-                    Node2d::MainPass,
+                    Node2d::StartMainPass,
+                    Node2d::MainTransparentPass,
+                    Node2d::EndMainPass,
                     Node2d::Tonemapping,
                     Node2d::EndMainPassPostProcessing,
                     Node2d::Upscaling,

crates/bevy_core_pipeline/src/msaa_writeback.rs

@@ -31,7 +31,7 @@ impl Plugin for MsaaWritebackPlugin {
         {
             render_app
                 .add_render_graph_node::<MsaaWritebackNode>(Core2d, Node2d::MsaaWriteback)
-                .add_render_graph_edge(Core2d, Node2d::MsaaWriteback, Node2d::MainPass);
+                .add_render_graph_edge(Core2d, Node2d::MsaaWriteback, Node2d::StartMainPass);
         }
         {
             render_app

crates/bevy_sprite/src/mesh2d/material.rs

@@ -389,7 +389,7 @@ pub fn queue_material2d_meshes<M: Material2d>(
     }
 
     for (view, visible_entities, tonemapping, dither, mut transparent_phase) in &mut views {
-        let draw_transparent_pbr = transparent_draw_functions.read().id::<DrawMaterial2d<M>>();
+        let draw_transparent_2d = transparent_draw_functions.read().id::<DrawMaterial2d<M>>();
 
         let mut view_key = Mesh2dPipelineKey::from_msaa_samples(msaa.samples())
             | Mesh2dPipelineKey::from_hdr(view.hdr);
@@ -410,7 +410,7 @@ pub fn queue_material2d_meshes<M: Material2d>(
             let Some(mesh_instance) = render_mesh_instances.get_mut(visible_entity) else {
                 continue;
             };
-            let Some(material2d) = render_materials.get(*material_asset_id) else {
+            let Some(material_2d) = render_materials.get(*material_asset_id) else {
                 continue;
             };
             let Some(mesh) = render_meshes.get(mesh_instance.mesh_asset_id) else {
@@ -424,7 +424,7 @@ pub fn queue_material2d_meshes<M: Material2d>(
                 &material2d_pipeline,
                 Material2dKey {
                     mesh_key,
-                    bind_group_data: material2d.key.clone(),
+                    bind_group_data: material_2d.key.clone(),
                 },
                 &mesh.layout,
             );
@@ -437,18 +437,18 @@ pub fn queue_material2d_meshes<M: Material2d>(
                 }
             };
 
-            mesh_instance.material_bind_group_id = material2d.get_bind_group_id();
+            mesh_instance.material_bind_group_id = material_2d.get_bind_group_id();
 
             let mesh_z = mesh_instance.transforms.transform.translation.z;
             transparent_phase.add(Transparent2d {
                 entity: *visible_entity,
-                draw_function: draw_transparent_pbr,
+                draw_function: draw_transparent_2d,
                 pipeline: pipeline_id,
                 // NOTE: Back-to-front ordering for transparent with ascending sort means far should have the
                 // lowest sort key and getting closer should increase. As we have
                 // -z in front of the camera, the largest distance is -far with values increasing toward the
                 // camera. As such we can just use mesh_z as the distance
-                sort_key: FloatOrd(mesh_z + material2d.depth_bias),
+                sort_key: FloatOrd(mesh_z + material_2d.depth_bias),
                 // Batching is done in batch_and_prepare_render_phase
                 batch_range: 0..1,
                 extra_index: PhaseItemExtraIndex::NONE,

crates/bevy_ui/src/render/mod.rs

@@ -126,7 +126,7 @@ pub fn build_ui_render(app: &mut App) {
     if let Some(graph_2d) = graph.get_sub_graph_mut(Core2d) {
         graph_2d.add_sub_graph(SubGraphUi, ui_graph_2d);
         graph_2d.add_node(NodeUi::UiPass, RunGraphOnViewNode::new(SubGraphUi));
-        graph_2d.add_node_edge(Node2d::MainPass, NodeUi::UiPass);
+        graph_2d.add_node_edge(Node2d::EndMainPass, NodeUi::UiPass);
         graph_2d.add_node_edge(Node2d::EndMainPassPostProcessing, NodeUi::UiPass);
         graph_2d.add_node_edge(NodeUi::UiPass, Node2d::Upscaling);
     }