Struct WgpuRenderer 

pub struct WgpuRenderer { /* private fields */ }

WGPU-based renderer for GPU-accelerated 2D rendering.

This renderer supports:

• GPU-accelerated shape rendering (rectangles, rounded rectangles)
• Gradients (solid, linear, radial)
• GPU text rendering via retained raster image batches
• Cross-platform support (Desktop, Web, Android)

Implementations

impl WgpuRenderer

pub fn new(fonts: &[&[u8]]) -> Self

Create a new WGPU renderer.

• fonts – font bytes to load, ordered by priority (first = highest priority). Pass &[] to load no fonts; text will not render until fonts are provided.

Call init_gpu before rendering.

pub fn with_font_set(fonts: SoftwareTextFontSet) -> Self

Create a renderer over an already-parsed font set.

Measurement and rasterization both take clones of this one set, so an app-supplied family resolves identically on both sides.

pub fn with_text_system(text_system: WgpuTextSystem) -> Self

pub fn init_gpu( &mut self, device: Arc<Device>, queue: Arc<Queue>, surface_format: TextureFormat, adapter_backend: Backend, )

Initialize GPU resources with a WGPU device and queue.

Replacing a live renderer (Android surface recreation, device loss) drops every retained replay slot with the old GpuRenderer, so the bypass contract fails closed BEFORE the new renderer exists: every slot confirmation is revoked and the feed generation bumped — no scene build may omit primitives against buffers that died, and already-built frames rematerialize their bypassed spans instead of referencing the dead renderer’s slot ids.

pub fn note_surface_reconfigured(&mut self)

Record that the surface was reconfigured (resize, format change, swapchain recreation): bumps the surface epoch stamped into every subsequent packet, so a packet built against the previous configuration is cancelled by the present stage instead of drawn.

pub fn set_root_scale(&mut self, scale: f32)

Set root scale factor for text rendering (e.g., density scaling on Android)

pub fn root_scale(&self) -> f32

pub fn render( &mut self, view: &TextureView, width: u32, height: u32, ) -> Result<(), WgpuRendererError>

Render the scene to a texture view.

Producer first, present second: the frontend lowers the frame into a [frame_packet::FramePacket] (direct root, root surface, and dev overlay alike), the GPU renderer consumes it, and the present stage’s returns — the recycled scene and the replay ack — fold back into the frontend afterwards.

pub fn capture_frame( &mut self, width: u32, height: u32, ) -> Result<CapturedFrame, WgpuRendererError>

Render the current scene into an RGBA pixel buffer for robot tests.

Uses the renderer’s configured root scale.

pub fn capture_frame_with_scale( &mut self, width: u32, height: u32, root_scale: f32, ) -> Result<CapturedFrame, WgpuRendererError>

Render the current scene into an RGBA pixel buffer with an explicit scale.

pub fn last_frame_stats(&self) -> Option<RenderStatsSnapshot>

pub fn debug_cpu_allocation_stats(&self) -> DebugCpuAllocationStats

pub fn try_device(&self) -> Option<&Device>

Return the WGPU device when GPU resources are initialized.

Trait Implementations

impl Default for WgpuRenderer

fn default() -> Self

Returns the “default value” for a type.

impl Renderer for WgpuRenderer

type Scene = Scene

type Error = WgpuRendererError

fn attach_app_context_services(&mut self, app_context: &AppContext)

Installs renderer-provided app services into the target AppContext.

fn scene(&self) -> &Self::Scene

fn scene_mut(&mut self) -> &mut Self::Scene

fn rebuild_scene( &mut self, layout_tree: &LayoutTree, _viewport: Size, ) -> Result<(), Self::Error>

fn rebuild_scene_from_applier( &mut self, applier: &mut MemoryApplier, root: NodeId, _viewport: Size, ) -> Result<(), Self::Error>

Rebuilds the scene by traversing the LayoutNode tree directly via Applier.

fn update_scene_from_applier( &mut self, applier: &mut MemoryApplier, root: NodeId, viewport: Size, dirty_nodes: &[NodeId], ) -> Result<(), Self::Error>

fn update_visual_scene_from_applier( &mut self, applier: &mut MemoryApplier, root: NodeId, viewport: Size, dirty_nodes: &[NodeId], ) -> Result<(), Self::Error>

fn draw_dev_overlay(&mut self, text: &str, viewport: Size)

Draw a development overlay (e.g., FPS counter) on top of the scene.

fn needs_frame_warmup(&self) -> bool

Returns whether renderer-side cache materialization needs a visible follow-up frame.