Struct SortedRenderPhase 

pub struct SortedRenderPhase<I>
where
    I: SortedPhaseItem,
{
    pub items: IndexMap<(Entity, MainEntity), I, EntityHash>,
    pub transient_items: Vec<(Entity, MainEntity)>,
}

A collection of all items to be rendered that will be encoded to GPU commands for a single render phase for a single view.

Each view (camera, or shadow-casting light, etc.) can have one or multiple render phases. They are used to queue entities for rendering. Multiple phases might be required due to different sorting/batching behaviors (e.g. opaque: front to back, transparent: back to front) or because one phase depends on the rendered texture of the previous phase (e.g. for screen-space reflections). All PhaseItems are then rendered using a single TrackedRenderPass. The render pass might be reused for multiple phases to reduce GPU overhead.

This flavor of render phase is used only for meshes that need to be sorted back-to-front, such as transparent meshes. For items that don’t need strict sorting, BinnedRenderPhase is preferred, for performance.

Fields

items: IndexMap<(Entity, MainEntity), I, EntityHash>

The items within this SortedRenderPhase.

transient_items: Vec<(Entity, MainEntity)>

Items within this render phase that will be automatically removed after this frame.

Implementations

impl<I> SortedRenderPhase<I>

where I: SortedPhaseItem,

pub fn add_retained(&mut self, item: I)

Adds a PhaseItem to this render phase, which will persist between frames until removed.

Examples found in repository

examples/shader_advanced/custom_shader_instancing.rs (lines 180-203)

fn queue_custom(
    transparent_3d_draw_functions: Res<DrawFunctions<Transparent3d>>,
    custom_pipeline: Res<CustomPipeline>,
    mut pipelines: ResMut<SpecializedMeshPipelines<CustomPipeline>>,
    pipeline_cache: Res<PipelineCache>,
    meshes: Res<RenderAssets<RenderMesh>>,
    render_mesh_instances: Res<RenderMeshInstances>,
    maybe_batched_instance_buffers: Option<
        Res<BatchedInstanceBuffers<MeshUniform, MeshInputUniform>>,
    >,
    material_meshes: Query<(Entity, &MainEntity), With<InstanceMaterialData>>,
    mut transparent_render_phases: ResMut<ViewSortedRenderPhases<Transparent3d>>,
    views: Query<&ExtractedView>,
    view_key_cache: Res<ViewKeyCache>,
) {
    let draw_custom = transparent_3d_draw_functions.read().id::<DrawCustom>();

    for view in &views {
        let Some(transparent_phase) = transparent_render_phases.get_mut(&view.retained_view_entity)
        else {
            continue;
        };

        let Some(&view_key) = view_key_cache.get(&view.retained_view_entity) else {
            continue;
        };

        for (entity, main_entity) in &material_meshes {
            let Some(mesh_instance) = render_mesh_instances.render_mesh_queue_data(*main_entity)
            else {
                continue;
            };
            let Some(mesh) = meshes.get(mesh_instance.mesh_asset_id()) else {
                continue;
            };
            let key = view_key
                | MeshPipelineKey::from_primitive_topology_and_strip_index(
                    mesh.primitive_topology(),
                    mesh.index_format(),
                );
            let pipeline = pipelines
                .specialize(&pipeline_cache, &custom_pipeline, key, &mesh.layout)
                .unwrap();
            transparent_phase.add_retained(Transparent3d {
                sorting_info: TransparentSortingInfo3d::Sorted {
                    mesh_center: pbr::get_mesh_instance_world_from_local(
                        *main_entity,
                        mesh_instance.current_uniform_index,
                        &render_mesh_instances,
                        maybe_batched_instance_buffers.as_deref(),
                    )
                    .transform_point3(
                        meshes
                            .get(mesh_instance.mesh_asset_id())
                            .unwrap()
                            .aabb_center,
                    ),
                    depth_bias: 0.0,
                },
                entity: (entity, *main_entity),
                pipeline,
                draw_function: draw_custom,
                distance: 0.0,
                batch_range: 0..1,
                extra_index: PhaseItemExtraIndex::None,
                indexed: true,
            });
        }
    }
}

examples/2d/mesh2d_manual.rs (lines 426-438)

pub fn queue_colored_mesh2d(
    transparent_draw_functions: Res<DrawFunctions<Transparent2d>>,
    colored_mesh2d_pipeline: Res<ColoredMesh2dPipeline>,
    mut pipelines: ResMut<SpecializedRenderPipelines<ColoredMesh2dPipeline>>,
    pipeline_cache: Res<PipelineCache>,
    render_meshes: Res<RenderAssets<RenderMesh>>,
    render_mesh_instances: Res<RenderColoredMesh2dInstances>,
    mut transparent_render_phases: ResMut<ViewSortedRenderPhases<Transparent2d>>,
    views: Query<(&RenderVisibleEntities, &ExtractedView, &Msaa)>,
) {
    if render_mesh_instances.is_empty() {
        return;
    }
    // Iterate each view (a camera is a view)
    for (visible_entities, view, msaa) in &views {
        let Some(transparent_phase) = transparent_render_phases.get_mut(&view.retained_view_entity)
        else {
            continue;
        };

        let draw_colored_mesh2d = transparent_draw_functions.read().id::<DrawColoredMesh2d>();

        let mesh_key = Mesh2dPipelineKey::from_msaa_samples(msaa.samples())
            | Mesh2dPipelineKey::from_target_format(view.target_format);

        // Queue all entities visible to that view
        let Some(visible_entities) = visible_entities.get::<Mesh2d>() else {
            continue;
        };
        for (render_entity, visible_entity) in visible_entities.iter_visible() {
            if let Some(mesh_instance) = render_mesh_instances.get(visible_entity) {
                let mesh2d_handle = mesh_instance.mesh_asset_id;
                let mesh2d_transforms = &mesh_instance.transforms;
                // Get our specialized pipeline
                let mut mesh2d_key = mesh_key;
                let Some(mesh) = render_meshes.get(mesh2d_handle) else {
                    continue;
                };
                mesh2d_key |= Mesh2dPipelineKey::from_primitive_topology_and_strip_index(
                    mesh.primitive_topology(),
                    mesh.index_format(),
                );

                let pipeline_id =
                    pipelines.specialize(&pipeline_cache, &colored_mesh2d_pipeline, mesh2d_key);

                let mesh_z = mesh2d_transforms.world_from_local.translation.z;
                transparent_phase.add_retained(Transparent2d {
                    entity: (*render_entity, *visible_entity),
                    draw_function: draw_colored_mesh2d,
                    pipeline: pipeline_id,
                    // The 2d render items are sorted according to their z value before rendering,
                    // in order to get correct transparency
                    sort_key: FloatOrd(mesh_z),
                    // This material is not batched
                    batch_range: 0..1,
                    extra_index: PhaseItemExtraIndex::None,
                    extracted_index: usize::MAX,
                    indexed: mesh.indexed(),
                });
            }
        }
    }
}

examples/shader_advanced/custom_render_phase.rs (lines 620-644)

fn queue_custom_meshes(
    custom_draw_functions: Res<DrawFunctions<Stencil3d>>,
    mut pipelines: ResMut<SpecializedMeshPipelines<StencilPipeline>>,
    pipeline_cache: Res<PipelineCache>,
    custom_draw_pipeline: Res<StencilPipeline>,
    render_meshes: Res<RenderAssets<RenderMesh>>,
    render_mesh_instances: Res<RenderMeshInstances>,
    maybe_batched_instance_buffers: Option<
        Res<BatchedInstanceBuffers<MeshUniform, MeshInputUniform>>,
    >,
    mut custom_render_phases: ResMut<ViewSortedRenderPhases<Stencil3d>>,
    mut views: Query<(&ExtractedView, &RenderVisibleEntities)>,
    view_key_cache: Res<ViewKeyCache>,
    dirty_specializations: Res<DirtySpecializations>,
    mut pending_custom_mesh_queues: ResMut<PendingCustomMeshQueues>,
    has_marker: Query<(), With<DrawStencil>>,
) {
    for (view, visible_entities) in &mut views {
        let Some(custom_phase) = custom_render_phases.get_mut(&view.retained_view_entity) else {
            continue;
        };
        let draw_custom = custom_draw_functions.read().id::<DrawMesh3dStencil>();

        let Some(&view_key) = view_key_cache.get(&view.retained_view_entity) else {
            continue;
        };

        // Since our phase can work on any 3d mesh we can reuse the default mesh 3d filter
        let Some(render_visible_mesh_entities) = visible_entities.get::<Mesh3d>() else {
            continue;
        };

        let view_pending_custom_mesh_queues =
            pending_custom_mesh_queues.prepare_for_new_frame(view.retained_view_entity);

        // First, remove meshes that need to be respecialized, and those that were removed, from the bins.
        for &main_entity in dirty_specializations
            .iter_to_dequeue(view.retained_view_entity, render_visible_mesh_entities)
        {
            custom_phase.remove(Entity::PLACEHOLDER, main_entity);
        }

        for (render_entity, visible_entity) in dirty_specializations.iter_to_queue(
            view.retained_view_entity,
            render_visible_mesh_entities,
            &view_pending_custom_mesh_queues.prev_frame,
        ) {
            // We only want meshes with the marker component to be queued to our phase.
            if has_marker.get(*render_entity).is_err() {
                continue;
            }
            let Some(mesh_instance) = render_mesh_instances.render_mesh_queue_data(*visible_entity)
            else {
                // We couldn't fetch the mesh, probably because it hasn't been
                // loaded yet. Add the entity to the list of pending custom mesh
                // queues and bail.
                view_pending_custom_mesh_queues
                    .current_frame
                    .insert((*render_entity, *visible_entity));
                continue;
            };
            let Some(mesh) = render_meshes.get(mesh_instance.mesh_asset_id()) else {
                continue;
            };

            // Specialize the key for the current mesh entity
            // For this example we only specialize based on the mesh topology
            // but you could have more complex keys and that's where you'd need to create those keys
            let mut mesh_key = view_key;
            mesh_key |= MeshPipelineKey::from_primitive_topology_and_strip_index(
                mesh.primitive_topology(),
                mesh.index_format(),
            );

            let pipeline_id = pipelines.specialize(
                &pipeline_cache,
                &custom_draw_pipeline,
                mesh_key,
                &mesh.layout,
            );
            let pipeline_id = match pipeline_id {
                Ok(id) => id,
                Err(err) => {
                    error!("{}", err);
                    continue;
                }
            };
            // At this point we have all the data we need to create a phase item and add it to our
            // phase
            custom_phase.add_retained(Stencil3d {
                sorting_info: TransparentSortingInfo3d::Sorted {
                    mesh_center: pbr::get_mesh_instance_world_from_local(
                        *visible_entity,
                        mesh_instance.current_uniform_index,
                        &render_mesh_instances,
                        maybe_batched_instance_buffers.as_deref(),
                    )
                    .transform_point3(
                        render_meshes
                            .get(mesh_instance.mesh_asset_id())
                            .unwrap()
                            .aabb_center,
                    ),
                    depth_bias: 0.0,
                },
                distance: FloatOrd(0.0),
                entity: (Entity::PLACEHOLDER, *visible_entity),
                pipeline: pipeline_id,
                draw_function: draw_custom,
                // Sorted phase items aren't batched
                batch_range: 0..1,
                extra_index: PhaseItemExtraIndex::None,
                indexed: mesh.indexed(),
            });
        }
    }
}

pub fn add_transient(&mut self, item: I)

Adds a PhaseItem to this render phase, which will be automatically removed after this frame.

pub fn remove(&mut self, render_entity: Entity, main_entity: MainEntity)

Removes the PhaseItem corresponding to the given main-world entity from this render phase.

Examples found in repository

examples/shader_advanced/custom_render_phase.rs (line 570)

fn queue_custom_meshes(
    custom_draw_functions: Res<DrawFunctions<Stencil3d>>,
    mut pipelines: ResMut<SpecializedMeshPipelines<StencilPipeline>>,
    pipeline_cache: Res<PipelineCache>,
    custom_draw_pipeline: Res<StencilPipeline>,
    render_meshes: Res<RenderAssets<RenderMesh>>,
    render_mesh_instances: Res<RenderMeshInstances>,
    maybe_batched_instance_buffers: Option<
        Res<BatchedInstanceBuffers<MeshUniform, MeshInputUniform>>,
    >,
    mut custom_render_phases: ResMut<ViewSortedRenderPhases<Stencil3d>>,
    mut views: Query<(&ExtractedView, &RenderVisibleEntities)>,
    view_key_cache: Res<ViewKeyCache>,
    dirty_specializations: Res<DirtySpecializations>,
    mut pending_custom_mesh_queues: ResMut<PendingCustomMeshQueues>,
    has_marker: Query<(), With<DrawStencil>>,
) {
    for (view, visible_entities) in &mut views {
        let Some(custom_phase) = custom_render_phases.get_mut(&view.retained_view_entity) else {
            continue;
        };
        let draw_custom = custom_draw_functions.read().id::<DrawMesh3dStencil>();

        let Some(&view_key) = view_key_cache.get(&view.retained_view_entity) else {
            continue;
        };

        // Since our phase can work on any 3d mesh we can reuse the default mesh 3d filter
        let Some(render_visible_mesh_entities) = visible_entities.get::<Mesh3d>() else {
            continue;
        };

        let view_pending_custom_mesh_queues =
            pending_custom_mesh_queues.prepare_for_new_frame(view.retained_view_entity);

        // First, remove meshes that need to be respecialized, and those that were removed, from the bins.
        for &main_entity in dirty_specializations
            .iter_to_dequeue(view.retained_view_entity, render_visible_mesh_entities)
        {
            custom_phase.remove(Entity::PLACEHOLDER, main_entity);
        }

        for (render_entity, visible_entity) in dirty_specializations.iter_to_queue(
            view.retained_view_entity,
            render_visible_mesh_entities,
            &view_pending_custom_mesh_queues.prev_frame,
        ) {
            // We only want meshes with the marker component to be queued to our phase.
            if has_marker.get(*render_entity).is_err() {
                continue;
            }
            let Some(mesh_instance) = render_mesh_instances.render_mesh_queue_data(*visible_entity)
            else {
                // We couldn't fetch the mesh, probably because it hasn't been
                // loaded yet. Add the entity to the list of pending custom mesh
                // queues and bail.
                view_pending_custom_mesh_queues
                    .current_frame
                    .insert((*render_entity, *visible_entity));
                continue;
            };
            let Some(mesh) = render_meshes.get(mesh_instance.mesh_asset_id()) else {
                continue;
            };

            // Specialize the key for the current mesh entity
            // For this example we only specialize based on the mesh topology
            // but you could have more complex keys and that's where you'd need to create those keys
            let mut mesh_key = view_key;
            mesh_key |= MeshPipelineKey::from_primitive_topology_and_strip_index(
                mesh.primitive_topology(),
                mesh.index_format(),
            );

            let pipeline_id = pipelines.specialize(
                &pipeline_cache,
                &custom_draw_pipeline,
                mesh_key,
                &mesh.layout,
            );
            let pipeline_id = match pipeline_id {
                Ok(id) => id,
                Err(err) => {
                    error!("{}", err);
                    continue;
                }
            };
            // At this point we have all the data we need to create a phase item and add it to our
            // phase
            custom_phase.add_retained(Stencil3d {
                sorting_info: TransparentSortingInfo3d::Sorted {
                    mesh_center: pbr::get_mesh_instance_world_from_local(
                        *visible_entity,
                        mesh_instance.current_uniform_index,
                        &render_mesh_instances,
                        maybe_batched_instance_buffers.as_deref(),
                    )
                    .transform_point3(
                        render_meshes
                            .get(mesh_instance.mesh_asset_id())
                            .unwrap()
                            .aabb_center,
                    ),
                    depth_bias: 0.0,
                },
                distance: FloatOrd(0.0),
                entity: (Entity::PLACEHOLDER, *visible_entity),
                pipeline: pipeline_id,
                draw_function: draw_custom,
                // Sorted phase items aren't batched
                batch_range: 0..1,
                extra_index: PhaseItemExtraIndex::None,
                indexed: mesh.indexed(),
            });
        }
    }
}

pub fn clear(&mut self)

Removes all PhaseItems from this render phase.

pub fn recalculate_sort_keys(&mut self, view: &ExtractedView)

Populates whatever internal fields are necessary in order to perform the sort.

For example, for transparent 3D phases, this calculates the distance from each object to the view.

pub fn sort(&mut self)

Sorts all of its PhaseItems.

pub fn iter_entities(&self) -> impl Iterator<Item = Entity>

An Iterator through the associated Entity for each PhaseItem in order.

pub fn render<'w>( &self, render_pass: &mut TrackedRenderPass<'w>, world: &'w World, view: Entity, ) -> Result<(), DrawError>

Renders all of its PhaseItems using their corresponding draw functions.

Examples found in repository

examples/shader_advanced/custom_render_phase.rs (line 686)

fn custom_draw_system(
    world: &World,
    view: ViewQuery<(
        &ExtractedCamera,
        &ExtractedView,
        &ViewTarget,
        Option<&MainPassResolutionOverride>,
    )>,
    stencil_phases: Res<ViewSortedRenderPhases<Stencil3d>>,
    mut ctx: RenderContext,
) {
    let view_entity = view.entity();
    let (camera, extracted_view, target, resolution_override) = view.into_inner();

    let Some(stencil_phase) = stencil_phases.get(&extracted_view.retained_view_entity) else {
        return;
    };

    let mut render_pass = ctx.begin_tracked_render_pass(RenderPassDescriptor {
        label: Some("stencil pass"),
        // For the purpose of the example, we will write directly to the view target. A real
        // stencil pass would write to a custom texture and that texture would be used in later
        // passes to render custom effects using it.
        color_attachments: &[Some(target.get_color_attachment())],
        // We don't bind any depth buffer for this pass
        depth_stencil_attachment: None,
        timestamp_writes: None,
        occlusion_query_set: None,
        multiview_mask: None,
    });

    if let Some(viewport) =
        Viewport::from_viewport_and_override(camera.viewport.as_ref(), resolution_override)
    {
        render_pass.set_camera_viewport(&viewport);
    }

    if let Err(err) = stencil_phase.render(&mut render_pass, world, view_entity) {
        error!("Error encountered while rendering the stencil phase {err:?}");
    }
}

pub fn render_range<'w>( &self, render_pass: &mut TrackedRenderPass<'w>, world: &'w World, view: Entity, range: impl RangeBounds<usize>, ) -> Result<(), DrawError>

Renders all PhaseItems in the provided range (based on their index in self.items) using their corresponding draw functions.

Trait Implementations

impl<I> Default for SortedRenderPhase<I>

where I: SortedPhaseItem,

fn default() -> SortedRenderPhase<I>

Returns the “default value” for a type.