GeodePathCacheComponent.h File Reference

Per-entity cache of Geode's CPU encode pipeline output. More...

#include <optional>
#include "donner/base/Path.h"
#include "donner/svg/renderer/geode/GeodePathEncoder.h"

Include dependency graph for GeodePathCacheComponent.h:

Classes
struct	donner::geode::GeodePathCacheComponent
	Per-entity cache of Geode's encoded-path output (and strokeToFill result). Installed lazily by RendererGeode at the encode call sites via get_or_emplace; removed automatically when the source ComputedPathComponent updates or is destroyed. More...
struct	donner::geode::GeodePathCacheComponent::StrokeSlot
	Stroke-slot cache. Holds both the Path::strokeToFill output path and its encoded form, keyed by the source StrokeStyle. Invalidated whenever the fill slot is (geometry change, via the entt signal), or on stroke-key mismatch (stroke width/dash/cap/ join change via CSS — the old key no longer matches the new one, so the next access regenerates). 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 cache of Geode's CPU encode pipeline output.

Design doc: docs/design_docs/0030-geode_performance.md §Milestone 2.

GeodePathEncoder::encode (cubicToQuadratic → toMonotonic → band decomposition) is the Tier-3 hot path identified in 0030. Without a cache it runs every frame for every draw — 132 times per frame for lion.svg. This component holds the encode result across frames so re-rendering an unchanged document skips the CPU work entirely.

Invalidation is owned by RendererGeode, which listens on entt's on_update<ComputedPathComponent> + on_destroy<ComputedPathComponent> signals and removes this component whenever the underlying geometry changes. ShapeSystem's content-equality gate (see emplaceComputedPathIfChanged) ensures those signals only fire when the path actually changed, so idle re-renders leave the cache intact.

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Class Documentation

donner::geode::GeodePathCacheComponent::StrokeSlot

struct donner::geode::GeodePathCacheComponent::StrokeSlot

Stroke-slot cache. Holds both the Path::strokeToFill output path and its encoded form, keyed by the source StrokeStyle. Invalidated whenever the fill slot is (geometry change, via the entt signal), or on stroke-key mismatch (stroke width/dash/cap/ join change via CSS — the old key no longer matches the new one, so the next access regenerates).

Collaboration diagram for donner::geode::GeodePathCacheComponent::StrokeSlot:

Class Members
EncodedPath	strokedEncode	Cached encode of strokedPath. Produced by GeodePathEncoder::encode(strokedPath, strokeFillRule).
Path	strokedPath	Cached Path::strokeToFill output. Reused across draws of the same entity + stroke-key combination.
FillRule	strokeFillRule = FillRule::NonZero	Fill rule the stroke was encoded with. strokeToFill picks NonZero vs EvenOdd based on subpath topology, so this is derived and cached alongside the encode.
StrokeStyle	strokeKey	Equality key. Compared against the caller's StrokeStyle to detect stroke-parameter changes.