GeodeResidentPathComponent.h File Reference

Per-entity GPU residence for Geode's cached encoded-path geometry (design doc 0030 wave 2: "GPU residence"). More...

#include <atomic>
#include <cstdint>
#include <memory>
#include <vector>
#include "donner/svg/renderer/geode/GeodeWgpuUtil.h"

Include dependency graph for GeodeResidentPathComponent.h:

Classes
struct	donner::geode::GeodeResidentSlot
	GPU-resident geometry for one cached EncodedPath (a fill slot or a stroke slot). Owns a single combined-usage GPU buffer that holds the path's vertex quad, the six analytic dual-ray SSBO regions, and the per-draw uniform block, plus the cached fill bind group. The buffer and bind group are built once by GeoEncoder on first residence and reused every subsequent unchanged frame. More...
struct	donner::geode::GeodeResidentSlot::Region
	A byte sub-range of buffer. size == 0 is never bound directly - empty SSBO regions reserve a 4-byte zero-filled slot so the shader's band-count gate keeps them un-dereferenced (matching the wave-1 arena allocStorageOrDummy dummy). More...
struct	donner::geode::GeodeResidentPathComponent
	Sibling of GeodePathCacheComponent: holds the GPU residence for an entity's fill and stroke encodes. Installed lazily by RendererGeode at the solid-fill draw sites; removed by the same entt listener that clears GeodePathCacheComponent when geometry changes. More...

Namespaces
namespace	donner
	Top-level Donner namespace, which is split into different sub-namespaces such as donner::svg and donner::css.

Detailed Description

Per-entity GPU residence for Geode's cached encoded-path geometry (design doc 0030 wave 2: "GPU residence").

The M2 GeodePathCacheComponent keeps the CPU-side EncodedPath across frames, but wave 1 still re-uploaded that geometry to a fresh per-frame bump arena on every draw - the measured headline cost was a static Ghostscript Tiger writing ~1.44 MB per frame across 2,432 writeBuffer calls even though the CPU encode cache hit, plus one createBindGroup per draw (304/frame).

This component gives each cached path a persistent GPU buffer that survives frames, so an unchanged document's steady-state frame writes ~zero geometry bytes and re-uses a cached bind group. It lives BESIDE GeodePathCacheComponent on the same entity and is removed by the same ComputedPathComponent on_update / on_destroy listener (RendererGeode::Impl::onComputedPathChanged), so the GPU residence invalidates exactly when the geometry changes. Registry teardown (document close) destroys the component and RAII-frees the buffer - the eviction story for "many distinct documents".

Lives in donner::geode (not donner::svg::geode) to match the other Geode types referenced unqualified via geode:: inside donner::svg.

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Class Documentation

donner::geode::GeodeResidentSlot::Region

struct donner::geode::GeodeResidentSlot::Region

A byte sub-range of buffer. size == 0 is never bound directly - empty SSBO regions reserve a 4-byte zero-filled slot so the shader's band-count gate keeps them un-dereferenced (matching the wave-1 arena allocStorageOrDummy dummy).

Class Members
uint64_t	offset = 0
uint64_t	size = 0