| Flutter Impeller |

Public Types | Public Member Functions | Public Attributes | List of all members
impeller::Path::Polyline Struct Reference

`#include <path.h>`

## Public Types
using | PointBufferPtr = std::unique_ptr< std::vector< Point > >
using | ReclaimPointBufferCallback = std::function< void(PointBufferPtr)>

## Public Member Functions
| Polyline (PointBufferPtr point_buffer, ReclaimPointBufferCallback reclaim)
| Polyline (Polyline &&other)
| ~Polyline ()
Point & | GetPoint (size_t index) const
std::tuple< size_t, size_t > | GetContourPointBounds (size_t contour_index) const

## Public Attributes
PointBufferPtr | points
std::vector< PolylineContour > | contours

## Detailed Description

One or more contours represented as a series of points and indices in the point vector representing the start of a new contour.

Polylines are ephemeral and meant to be used by the tessellator. They do not allocate their own point vectors to allow for optimizations around allocation and reuse of arenas.

Definition at line 146 of file path.h.

## Member Typedef Documentation

## ◆ PointBufferPtr

using impeller::Path::Polyline::PointBufferPtr = std::unique_ptr<std::vector<Point> >

The signature of a method called when it is safe to reclaim the point buffer provided to the constructor of this object.

Definition at line 149 of file path.h.

## ◆ ReclaimPointBufferCallback

using impeller::Path::Polyline::ReclaimPointBufferCallback = std::function<void(PointBufferPtr)>

Definition at line 150 of file path.h.

## Constructor & Destructor Documentation

## ◆ Polyline() [1/2]

impeller::Path::Polyline::Polyline | ( | PointBufferPtr | point_buffer,
|  | ReclaimPointBufferCallback | reclaim
| ) |  |

The buffer will be cleared and returned at the destruction of this polyline.

Definition at line 262 of file path.cc.

264 : points(std::move(point_buffer)), reclaim_points_(std::move(reclaim)) {
265 FML_DCHECK(points);
266 }
impeller::Path::Polyline::points
PointBufferPtr points
Definition: path.h:161

References points.

## ◆ Polyline() [2/2]

impeller::Path::Polyline::Polyline | ( | Path::Polyline && | other | ) |

Definition at line 268 of file path.cc.

268 {
269 points = std::move(other.points);
270 reclaim_points_ = std::move(other.reclaim_points_);
271 contours = std::move(other.contours);
272 }
impeller::Path::Polyline::contours
std::vector< PolylineContour > contours
Definition: path.h:167

## ◆ ~Polyline()

impeller::Path::Polyline::~Polyline | ( |  | ) |

Definition at line 274 of file path.cc.

274 {
275 if (reclaim_points_) {
276 points->clear();
277 reclaim_points_(std::move(points));
278 }
279 }

## Member Function Documentation

## ◆ GetContourPointBounds()

std::tuple< size_t, size_t > impeller::Path::Polyline::GetContourPointBounds | ( | size_t | contour_index | ) | const

Convenience method to compute the start (inclusive) and end (exclusive) point of the given contour index.

The contour_index parameter is clamped to contours.size().

Definition at line 80 of file path.cc.

81 {
82 if (contour_index >= contours.size()) {
83 return {points->size(), points->size()};
84 }
85 const size_t start_index = contours.at(contour_index).start_index;
86 const size_t end_index = (contour_index >= contours.size() - 1)
87 ? points->size()
88 : contours.at(contour_index + 1).start_index;
89 return std::make_tuple(start_index, end_index);
90 }

## ◆ GetPoint()

Point& impeller::Path::Polyline::GetPoint | ( | size_t | index | ) | const
| inline

Definition at line 163 of file path.h.

163 { return (*points)[index]; }

References points.

## Member Data Documentation

## ◆ contours

std::vector<PolylineContour> impeller::Path::Polyline::contours

Contours are disconnected pieces of a polyline, such as when a MoveTo was issued on a PathBuilder.

Definition at line 167 of file path.h.

## ◆ points

PointBufferPtr impeller::Path::Polyline::points

Points in the polyline, which may represent multiple contours specified by indices in |contours|.

Definition at line 161 of file path.h.

Referenced by impeller::BM_Polyline(), GetPoint(), and Polyline().

The documentation for this struct was generated from the following files:

- impeller/geometry/path.h
- impeller/geometry/path.cc