pulp::canvas::PathMeasure Class Reference

#include <path_measure.hpp>

Public Member Functions
	PathMeasure ()=default
	PathMeasure (const Path &path, float tolerance=default_tolerance)
	Measure path.
float	length () const
	Total length of every contour summed. 0 for an empty path.
bool	is_empty () const
size_t	contour_count () const
	Contours are the move_to-delimited subpaths, in path order.
float	contour_length (size_t index) const
bool	contour_is_closed (size_t index) const
	Whether contour index was closed with close().
float	contour_start (size_t index) const
	Distance at which contour index begins, measured from the start of the path.
std::optional< PathPose >	pose_at (float distance) const
	Position and unit tangent at distance along the path.
std::optional< Point2D >	position_at (float distance) const
	pose_at(distance)->position, for callers that do not need the tangent.
std::optional< Point2D >	tangent_at (float distance) const
	pose_at(distance)->tangent, for callers that do not need the position.
Path	segment (float start, float end) const
	The part of the path between two distances, as a new Path.

Static Public Attributes
static constexpr float	default_tolerance = 0.25f
	The default flattening tolerance, in path units.

Constructor & Destructor Documentation

PathMeasure() [1/2]

pulp::canvas::PathMeasure::PathMeasure ( )

default

PathMeasure() [2/2]

pulp::canvas::PathMeasure::PathMeasure ( const Path & path, float tolerance = default_tolerance )

explicit

Measure path.

tolerance is clamped to a small positive minimum, so a caller passing 0 gets the finest supported flattening rather than a hang.

Member Function Documentation

contour_count()

size_t pulp::canvas::PathMeasure::contour_count ( ) const

inline

Contours are the move_to-delimited subpaths, in path order.

A path with no length (a lone move_to, or repeated identical points) yields no contour, so every contour reported here has positive length.

contour_is_closed()

bool pulp::canvas::PathMeasure::contour_is_closed

(

size_t

index

)

const

Whether contour index was closed with close().

contour_length()

float pulp::canvas::PathMeasure::contour_length

(

size_t

index

)

const

contour_start()

float pulp::canvas::PathMeasure::contour_start

(

size_t

index

)

const

Distance at which contour index begins, measured from the start of the path.

contour_start(0) is always 0.

is_empty()

bool pulp::canvas::PathMeasure::is_empty ( ) const

inline

length()

float pulp::canvas::PathMeasure::length ( ) const

inline

Total length of every contour summed. 0 for an empty path.

pose_at()

std::optional< PathPose > pulp::canvas::PathMeasure::pose_at

(

float

distance

)

const

Position and unit tangent at distance along the path.

distance is CLAMPED to [0, length()], so an out-of-range value returns the nearest endpoint rather than nothing — a meter driven past its maximum should pin, not vanish. std::nullopt means the path has no length at all, which is the one case a caller must actually branch on.

position_at()

std::optional< Point2D > pulp::canvas::PathMeasure::position_at

(

float

distance

)

const

pose_at(distance)->position, for callers that do not need the tangent.

segment()

Path pulp::canvas::PathMeasure::segment	(	float	start,
		float	end ) const

The part of the path between two distances, as a new Path.

This is the trim behind a value arc or a reveal. Both distances are clamped to [0, length()]; if start >= end after clamping the result is an empty Path. Curves are split with de Casteljau, so the result keeps the source's curve verbs rather than degrading to line segments.

A closed contour that is trimmed is no longer closed: the result is the open run between the two distances, with no closing segment.

tangent_at()

std::optional< Point2D > pulp::canvas::PathMeasure::tangent_at

(

float

distance

)

const

pose_at(distance)->tangent, for callers that do not need the position.

Member Data Documentation

default_tolerance

float pulp::canvas::PathMeasure::default_tolerance = 0.25f

staticconstexpr

The default flattening tolerance, in path units.

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The documentation for this class was generated from the following file:

• /home/runner/work/pulp/pulp/core/canvas/include/pulp/canvas/path_measure.hpp