GeoEncoder.h File Reference

Drawing API for the Geode GPU renderer. More...

#include <cstdint>
#include <memory>
#include <span>
#include <webgpu/webgpu.hpp>
#include "donner/base/Box.h"
#include "donner/base/FillRule.h"
#include "donner/base/Transform.h"
#include "donner/base/Vector2.h"
#include "donner/css/Color.h"

Include dependency graph for GeoEncoder.h:

Classes
struct	donner::geode::LinearGradientParams
	Parameters for a linear gradient fill at the Geode drawing layer. More...
struct	donner::geode::LinearGradientParams::Stop
	Gradient stops. Colors are in straight alpha, 0..1 per channel — the encoder premultiplies before upload. Offsets must be in [0, 1]. More...
struct	donner::geode::RadialGradientParams
	Parameters for a radial gradient fill at the Geode drawing layer. More...
class	donner::geode::GeoEncoder
	Drawing API for the Geode GPU renderer. More...
struct	donner::geode::GeoEncoder::PatternPaint
	Describes a pattern tile used as a paint source for fillPathPattern. More...

Namespaces
namespace	donner
	Top-level Donner namespace, which is split into different sub-namespaces such as donner::svg and donner::css.
namespace	donner::svg
	Donner SVG library, which can load, manipulate and render SVG files.

Detailed Description

Drawing API for the Geode GPU renderer.

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Class Documentation

donner::geode::LinearGradientParams::Stop

struct donner::geode::LinearGradientParams::Stop

Gradient stops. Colors are in straight alpha, 0..1 per channel — the encoder premultiplies before upload. Offsets must be in [0, 1].

A hard cap of 16 stops is enforced inside the encoder to match the fixed-size uniform buffer layout in slug_gradient.wgsl. Stops beyond the cap are silently truncated — a follow-up will move stop storage to a texture lookup (GeodeGradientCacheComponent) to lift this limit. A single gradient stop: normalized offset and premultiplied linear RGBA.

Class Members
float	offset = 0.0f	Stop offset in [0, 1].
float	rgba[4] = {0.0f, 0.0f, 0.0f, 1.0f}	Premultiplied linear RGBA color.

donner::geode::GeoEncoder::PatternPaint

struct donner::geode::GeoEncoder::PatternPaint

Describes a pattern tile used as a paint source for fillPathPattern.

The tile texture is expected to contain pre-rendered pattern content in premultiplied RGBA. The Slug fill shader samples it with the Repeat wrap mode (equivalent to SVG <pattern> default behaviour) using the provided transform to map path-space positions into tile-space.

Collaboration diagram for donner::geode::GeoEncoder::PatternPaint:

Class Members
double	opacity = 1.0	Multiplicative alpha applied to the sampled tile color. Usually fill-opacity * opacity.
Transform2d	patternFromPath	Transform from path space (where the path being filled lives) to pattern tile space. Typically inverse(targetFromPattern) composed with the current encoder transform — the RendererGeode layer builds the right composition.
Texture	tile	Pre-rendered tile texture (RGBA8, premultiplied).
Vector2d	tileSize	Size of the tile rectangle in pattern space (width, height). The shader uses this to wrap sample positions via fract().