GeodePathEncoder.h File Reference

CPU-side Slug band decomposition: converts a Path into GPU-ready band data. More...

#include <cstdint>
#include <span>
#include <vector>
#include "donner/base/Box.h"
#include "donner/base/Vector2.h"

Include dependency graph for GeodePathEncoder.h:

Classes
struct	donner::geode::EncodedPath
	GPU-ready encoded path data produced by the Slug band decomposition algorithm. More...
struct	donner::geode::EncodedPath::Curve
	A quadratic Bézier curve segment (3 control points) stored as floats for GPU consumption. More...
struct	donner::geode::EncodedPath::Band
	Metadata for one horizontal band. More...
struct	donner::geode::EncodedPath::Vertex
	Vertex for the band bounding quad (input to the Slug vertex shader). More...
class	donner::geode::GeodePathEncoder
	Encodes a Path into Slug band decomposition format for GPU rendering. More...

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

Detailed Description

CPU-side Slug band decomposition: converts a Path into GPU-ready band data.

---

Class Documentation

donner::geode::EncodedPath::Curve

struct donner::geode::EncodedPath::Curve

A quadratic Bézier curve segment (3 control points) stored as floats for GPU consumption.

Class Members
float	p0x
float	p0y	Start point.
float	p1x
float	p1y	Control point.
float	p2x
float	p2y	End point.

donner::geode::EncodedPath::Band

struct donner::geode::EncodedPath::Band

Metadata for one horizontal band.

Layout matches the WGSL Band struct in shaders/slug_fill.wgsl exactly (8 × 4 bytes = 32 bytes per band). Two trailing pad fields are required because storage buffer struct stride must be 16-byte aligned, and without them WGSL would round the struct to 32 bytes anyway.

Class Members
float	_pad0	Padding to match WGSL stride.
float	_pad1	Padding to match WGSL stride.
uint32_t	curveCount	Number of curves intersecting this band.
uint32_t	curveStart	Index of the first curve in this band's curve range.
float	xMax	Right extent of curves in this band.
float	xMin	Left extent of curves in this band.
float	yMax	Top edge of the band (in path space).
float	yMin	Bottom edge of the band (in path space).

donner::geode::EncodedPath::Vertex

struct donner::geode::EncodedPath::Vertex

Vertex for the band bounding quad (input to the Slug vertex shader).

Class Members
uint32_t	bandIndex	Which band this vertex belongs to.
float	normalX
float	normalY	Outward normal (for dynamic half-pixel dilation).
float	posX
float	posY	Position in path space.