bevyengine/bevy

bevy_core_pipeline

The shared 2D and 3D core render pipeline. Defines the standard render-graph nodes (clear, prepass, main pass, tonemapping, bloom, OIT) and the standard phase-item types (Opaque3d, AlphaMask3d, Transparent3d, Opaque2d, Transparent2d).

Purpose

bevy_core_pipeline is the layer between bevy_render and the per-domain rendering crates (bevy_pbr, bevy_sprite_render, bevy_ui_render). It provides the scaffolding both 2D and 3D pipelines share:

Core 2D pipeline (core_2d/) — the 2D render graph and phase items.
Core 3D pipeline (core_3d/) — the 3D render graph and phase items, including OIT (order-independent transparency).
Tonemapping (tonemapping/) — exposure + tonemap shader, with built-in tonemap operators (Reinhard, ACES, AgX, BlenderFilmic, …).
Bloom (bloom/) — physically based bloom.
Skybox (skybox/) — cubemap-based sky.
MSAA — multi-sample anti-aliasing setup.
Prepass (prepass/) — depth, normal, motion-vector pre-passes used by TAA, SSAO, deferred.
Auto-exposure (auto_exposure/) — luminance-based exposure adjustment.
OIT (oit/) — order-independent transparency.

Directory layout

crates/bevy_core_pipeline/src/
├── lib.rs              # CorePipelinePlugin
├── core_2d/            # 2D pipeline
├── core_3d/            # 3D pipeline (forward + deferred wiring)
├── prepass/            # Depth/normal/motion prepass
├── tonemapping/        # Tonemap node + presets
├── bloom/              # Bloom downsample/upsample chain
├── skybox/             # Skybox node + cubemap material
├── auto_exposure/      # Luminance-driven exposure
├── motion_blur/        # Motion blur
├── oit/                # Order-independent transparency
├── msaa_writeback/     # MSAA resolve to non-MSAA target
├── post_process/       # Shared post-process plumbing
├── upscaling/          # Render-target upscaling
├── dof/                # Depth of field (lives here, not in bevy_post_process)
└── …

Key abstractions

Type	File	Description
`Core2dPlugin`, `Core3dPlugin`	`crates/bevy_core_pipeline/src/{core_2d,core_3d}/mod.rs`	Per-domain plugins.
`Opaque3d`, `AlphaMask3d`, `Transparent3d`	`crates/bevy_core_pipeline/src/core_3d/main_opaque_pass_3d_node.rs` etc	3D phase items.
`Opaque2d`, `Transparent2d`	`crates/bevy_core_pipeline/src/core_2d/`	2D phase items.
`Camera3d`, `Camera2d`	`crates/bevy_core_pipeline/src/{core_2d,core_3d}/camera_*.rs`	Marker components opting cameras into a pipeline.
`Tonemapping`	`crates/bevy_core_pipeline/src/tonemapping/mod.rs`	Per-camera tonemap operator.
`Bloom`	`crates/bevy_core_pipeline/src/bloom/settings.rs`	Per-camera bloom settings.
`MotionBlur`	`crates/bevy_core_pipeline/src/motion_blur/mod.rs`	Per-camera motion-blur settings.
`DepthOfField`	`crates/bevy_core_pipeline/src/dof/mod.rs`	DOF settings.
`Skybox`	`crates/bevy_core_pipeline/src/skybox/mod.rs`	Cubemap skybox component.

How it works

On adding Core3dPlugin, the render graph gains:

Clear → MainPrepass (optional) → MainOpaquePass → MainTransparentPass → Tonemapping → Bloom → Upscaling → Output

Each box is a render-graph node. Plugins like bevy_pbr::PbrPlugin or bevy_anti_alias::TemporalAntiAliasPlugin insert their own nodes around these.

The 2D pipeline is simpler: clear, sprite/UI passes, tonemapping, output.

Integration points

Depends on: bevy_render, bevy_camera, bevy_color, bevy_image, bevy_math, bevy_asset.
Depended on by: bevy_pbr, bevy_sprite_render, bevy_ui_render, bevy_anti_alias, bevy_post_process, bevy_solari, bevy_gizmos_render.

Entry points for modification

New tonemap operator: edit tonemapping/mod.rs to add a variant and tonemapping_shared.wgsl for the math.
New phase item: template off Opaque3d. The trait-impl boilerplate is in crates/bevy_render/src/render_phase/.
Insert a custom render-graph node: any plugin can call RenderGraph::add_node / add_node_edge against the core 3d/2d sub-graphs.