Struct webrender::render_backend::RenderBackend

pub struct RenderBackend {

    api_rx: Receiver<ApiMsg>,
    result_tx: Sender<ResultMsg>,
    scene_tx: Sender<SceneBuilderRequest>,
    gpu_cache: GpuCache,
    resource_cache: ResourceCache,
    frame_config: FrameBuilderConfig,
    default_compositor_kind: CompositorKind,
    documents: FastHashMap<DocumentId, Document>,
    notifier: Box<dyn RenderNotifier>,
    sampler: Option<Box<dyn AsyncPropertySampler + Send>>,
    size_of_ops: Option<MallocSizeOfOps>,
    debug_flags: DebugFlags,
    namespace_alloc_by_client: bool,
    recycler: Recycler,
    capture_config: Option<CaptureConfig>,
    tile_caches: FastHashMap<SliceId, Box<TileCacheInstance>>,
    frame_publish_id: FramePublishId,
}

The render backend is responsible for transforming high level display lists into GPU-friendly work which is then submitted to the renderer in the form of a frame::Frame.

The render backend operates on its own thread.

Fields

api_rx: Receiver<ApiMsg>

result_tx: Sender<ResultMsg>

scene_tx: Sender<SceneBuilderRequest>

gpu_cache: GpuCache

resource_cache: ResourceCache

frame_config: FrameBuilderConfig

default_compositor_kind: CompositorKind

documents: FastHashMap<DocumentId, Document>

notifier: Box<dyn RenderNotifier>

sampler: Option<Box<dyn AsyncPropertySampler + Send>>

size_of_ops: Option<MallocSizeOfOps>

debug_flags: DebugFlags

namespace_alloc_by_client: bool

recycler: Recycler

capture_config: Option<CaptureConfig>

If Some, do ‘sequence capture’ logging, recording updated documents, frames, etc. This is set only through messages from the scene builder, so all control of sequence capture goes through there.

tile_caches: FastHashMap<SliceId, Box<TileCacheInstance>>

A map of tile caches. These are stored in the backend as they are persisted between both frame and scenes.

frame_publish_id: FramePublishId

The id of the latest PublishDocument

Implementations

impl RenderBackend

pub fn new( api_rx: Receiver<ApiMsg>, result_tx: Sender<ResultMsg>, scene_tx: Sender<SceneBuilderRequest>, resource_cache: ResourceCache, notifier: Box<dyn RenderNotifier>, frame_config: FrameBuilderConfig, sampler: Option<Box<dyn AsyncPropertySampler + Send>>, size_of_ops: Option<MallocSizeOfOps>, debug_flags: DebugFlags, namespace_alloc_by_client: bool, ) -> RenderBackend

pub fn next_namespace_id() -> IdNamespace

pub fn run(&mut self)

fn process_transaction( &mut self, txns: Vec<Box<BuiltTransaction>>, result_tx: Option<Sender<SceneSwapResult>>, frame_counter: &mut u32, ) -> bool

fn process_api_msg( &mut self, msg: ApiMsg, frame_counter: &mut u32, ) -> RenderBackendStatus

fn process_scene_builder_result( &mut self, msg: SceneBuilderResult, frame_counter: &mut u32, ) -> RenderBackendStatus

fn update_frame_builder_config(&self)

fn prepare_for_frames(&mut self)

fn bookkeep_after_frames(&mut self)

fn requires_frame_build(&mut self) -> bool

fn prepare_transactions( &mut self, txns: Vec<Box<TransactionMsg>>, frame_counter: &mut u32, )

fn maybe_force_nop_documents<F>( &mut self, frame_counter: &mut u32, document_already_present: F, )

where F: Fn(DocumentId) -> bool,

In certain cases, resources shared by multiple documents have to run maintenance operations, like cleaning up unused cache items. In those cases, we are forced to build frames for all documents, however we may not have a transaction ready for every document - this method calls update_document with the details of a fake, nop transaction just to force a frame build.

fn update_document( &mut self, document_id: DocumentId, resource_updates: Vec<ResourceUpdate>, frame_ops: Vec<FrameMsg>, notifications: Vec<NotificationRequest>, render_frame: bool, render_reasons: RenderReasons, generated_frame_id: Option<u64>, invalidate_rendered_frame: bool, frame_counter: &mut u32, has_built_scene: bool, start_time: Option<u64>, ) -> bool

fn send_backend_message(&self, msg: SceneBuilderRequest)

fn report_memory(&mut self, tx: Sender<Box<MemoryReport>>)

fn save_capture_sequence(&mut self)

impl RenderBackend

fn save_capture(&mut self, root: PathBuf, bits: CaptureBits) -> DebugOutput

fn start_capture_sequence(&mut self, root: PathBuf, bits: CaptureBits)

fn stop_capture_sequence(&mut self)