Flutter Impeller
impeller::PointFieldGeometry Class Referencefinal

A geometry class specialized for Canvas::DrawPoints. More...

#include <point_field_geometry.h>

Inheritance diagram for impeller::PointFieldGeometry:
impeller::Geometry

Public Member Functions

 PointFieldGeometry (const Point *points, size_t point_count, Scalar radius, bool round)
 
 ~PointFieldGeometry () override
 
std::optional< RectGetCoverage (const Matrix &transform) const override
 
- Public Member Functions inherited from impeller::Geometry
virtual ~Geometry ()
 
virtual GeometryResult::Mode GetResultMode () const
 
virtual bool CoversArea (const Matrix &transform, const Rect &rect) const
 Determines if this geometry, transformed by the given transform, will completely cover all surface area of the given rect. More...
 
virtual bool IsAxisAlignedRect () const
 
virtual bool CanApplyMaskFilter () const
 
virtual Scalar ComputeAlphaCoverage (const Matrix &transform) const
 

Additional Inherited Members

- Static Public Member Functions inherited from impeller::Geometry
static std::unique_ptr< GeometryMakeFillPath (const flutter::DlPath &path, std::optional< Rect > inner_rect=std::nullopt)
 
static std::unique_ptr< GeometryMakeStrokePath (const flutter::DlPath &path, const StrokeParameters &stroke={})
 
static std::unique_ptr< GeometryMakeCover ()
 
static std::unique_ptr< GeometryMakeRect (const Rect &rect)
 
static std::unique_ptr< GeometryMakeOval (const Rect &rect)
 
static std::unique_ptr< GeometryMakeLine (const Point &p0, const Point &p1, const StrokeParameters &stroke)
 
static std::unique_ptr< GeometryMakeCircle (const Point &center, Scalar radius)
 
static std::unique_ptr< GeometryMakeStrokedCircle (const Point &center, Scalar radius, Scalar stroke_width)
 
static std::unique_ptr< GeometryMakeFilledArc (const Rect &oval_bounds, Degrees start, Degrees sweep, bool include_center)
 
static std::unique_ptr< GeometryMakeStrokedArc (const Rect &oval_bounds, Degrees start, Degrees sweep, const StrokeParameters &stroke)
 
static std::unique_ptr< GeometryMakeRoundRect (const Rect &rect, const Size &radii)
 
static std::unique_ptr< GeometryMakeRoundSuperellipse (const Rect &rect, Scalar corner_radius)
 
static Scalar ComputeStrokeAlphaCoverage (const Matrix &entity, Scalar stroke_width)
 Compute an alpha value to simulate lower coverage of fractional pixel strokes. More...
 
static GeometryResult ComputePositionGeometry (const ContentContext &renderer, const Tessellator::VertexGenerator &generator, const Entity &entity, RenderPass &pass)
 

Detailed Description

A geometry class specialized for Canvas::DrawPoints.

Does not hold ownership of the allocated point data, which is expected to be maintained via the display list structure.

Definition at line 16 of file point_field_geometry.h.

Constructor & Destructor Documentation

◆ PointFieldGeometry()

impeller::PointFieldGeometry::PointFieldGeometry ( const Point points,
size_t  point_count,
Scalar  radius,
bool  round 
)

Definition at line 15 of file point_field_geometry.cc.

19  : point_count_(point_count),
20  radius_(radius),
21  round_(round),
22  points_(points) {}
std::vector< Point > points

◆ ~PointFieldGeometry()

impeller::PointFieldGeometry::~PointFieldGeometry ( )
overridedefault

Member Function Documentation

◆ GetCoverage()

std::optional< Rect > impeller::PointFieldGeometry::GetCoverage ( const Matrix transform) const
overridevirtual

Implements impeller::Geometry.

Definition at line 134 of file point_field_geometry.cc.

135  {
136  if (point_count_ > 0) {
137  // Doesn't use MakePointBounds as this isn't resilient to points that
138  // all lie along the same axis.
139  Scalar left = points_[0].x;
140  Scalar top = points_[0].y;
141  Scalar right = points_[0].x;
142  Scalar bottom = points_[0].y;
143  for (auto i = 1u; i < point_count_; i++) {
144  const Point point = points_[i];
145  left = std::min(left, point.x);
146  top = std::min(top, point.y);
147  right = std::max(right, point.x);
148  bottom = std::max(bottom, point.y);
149  }
150  Rect coverage = Rect::MakeLTRB(left - radius_, top - radius_,
151  right + radius_, bottom + radius_);
152  return coverage.TransformBounds(transform);
153  }
154  return std::nullopt;
155 }
float Scalar
Definition: scalar.h:19
TRect< Scalar > Rect
Definition: rect.h:792
TPoint< Scalar > Point
Definition: point.h:327
constexpr static TRect MakeLTRB(Type left, Type top, Type right, Type bottom)
Definition: rect.h:129

References impeller::TRect< Scalar >::MakeLTRB(), transform, impeller::TRect< T >::TransformBounds(), impeller::TPoint< T >::x, and impeller::TPoint< T >::y.

Referenced by impeller::testing::TEST_P().


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