Flutter Impeller
impeller::CircleGeometry Class Referencefinal

#include <circle_geometry.h>

Inheritance diagram for impeller::CircleGeometry:
impeller::Geometry

Public Member Functions

 CircleGeometry (const Point &center, Scalar radius)
 
 CircleGeometry (const Point &center, Scalar radius, Scalar stroke_width)
 
 ~CircleGeometry () override
 
bool CoversArea (const Matrix &transform, const Rect &rect) const override
 Determines if this geometry, transformed by the given transform, will completely cover all surface area of the given rect. More...
 
bool IsAxisAlignedRect () const override
 
Scalar ComputeAlphaCoverage (const Matrix &transform) const override
 
- Public Member Functions inherited from impeller::Geometry
virtual ~Geometry ()
 
virtual GeometryResult::Mode GetResultMode () const
 
virtual bool CanApplyMaskFilter () const
 

Additional Inherited Members

- Static Public Member Functions inherited from impeller::Geometry
static std::unique_ptr< GeometryMakeFillPath (const Path &path, std::optional< Rect > inner_rect=std::nullopt)
 
static std::unique_ptr< GeometryMakeStrokePath (const Path &path, Scalar stroke_width=0.0, Scalar miter_limit=4.0, Cap stroke_cap=Cap::kButt, Join stroke_join=Join::kMiter)
 
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, Scalar width, Cap cap)
 
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< GeometryMakeRoundRect (const Rect &rect, const Size &radii)
 
static std::unique_ptr< GeometryMakePointField (std::vector< Point > points, Scalar radius, bool round)
 
static Scalar ComputeStrokeAlphaCoverage (const Matrix &entity, Scalar stroke_width)
 Compute an alpha value to simulate lower coverage of fractional pixel strokes. More...
 
- Static Protected Member Functions inherited from impeller::Geometry
static GeometryResult ComputePositionGeometry (const ContentContext &renderer, const Tessellator::VertexGenerator &generator, const Entity &entity, RenderPass &pass)
 

Detailed Description

Definition at line 14 of file circle_geometry.h.

Constructor & Destructor Documentation

◆ CircleGeometry() [1/2]

impeller::CircleGeometry::CircleGeometry ( const Point center,
Scalar  radius 
)
explicit

Definition at line 15 of file circle_geometry.cc.

16  : center_(center), radius_(radius), stroke_width_(-1.0f) {
17  FML_DCHECK(radius >= 0);
18 }

◆ CircleGeometry() [2/2]

impeller::CircleGeometry::CircleGeometry ( const Point center,
Scalar  radius,
Scalar  stroke_width 
)
explicit

Definition at line 22 of file circle_geometry.cc.

25  : center_(center),
26  radius_(radius),
27  stroke_width_(std::max(stroke_width, 0.0f)) {
28  FML_DCHECK(radius >= 0);
29  FML_DCHECK(stroke_width >= 0);
30 }

References stroke_width.

◆ ~CircleGeometry()

impeller::CircleGeometry::~CircleGeometry ( )
overridedefault

Member Function Documentation

◆ ComputeAlphaCoverage()

Scalar impeller::CircleGeometry::ComputeAlphaCoverage ( const Matrix transform) const
overridevirtual

Reimplemented from impeller::Geometry.

Definition at line 33 of file circle_geometry.cc.

33  {
34  if (stroke_width_ < 0) {
35  return 1;
36  }
37  return Geometry::ComputeStrokeAlphaCoverage(transform, stroke_width_);
38 }

References impeller::Geometry::ComputeStrokeAlphaCoverage(), and transform.

◆ CoversArea()

bool impeller::CircleGeometry::CoversArea ( const Matrix transform,
const Rect rect 
) const
overridevirtual

Determines if this geometry, transformed by the given transform, will completely cover all surface area of the given rect.

This is a conservative estimate useful for certain optimizations.

Returns
true if the transformed geometry is guaranteed to cover the given rect. May return false in many undetected cases where the transformed geometry does in fact cover the rect.

Reimplemented from impeller::Geometry.

Definition at line 75 of file circle_geometry.cc.

76  {
77  return false;
78 }

◆ IsAxisAlignedRect()

bool impeller::CircleGeometry::IsAxisAlignedRect ( ) const
overridevirtual

Reimplemented from impeller::Geometry.

Definition at line 80 of file circle_geometry.cc.

80  {
81  return false;
82 }

The documentation for this class was generated from the following files:
stroke_width
const Scalar stroke_width
Definition: stroke_path_geometry.cc:297
transform
Matrix transform
Definition: gaussian_blur_filter_contents.cc:213
impeller::Geometry::ComputeStrokeAlphaCoverage
static Scalar ComputeStrokeAlphaCoverage(const Matrix &entity, Scalar stroke_width)
Compute an alpha value to simulate lower coverage of fractional pixel strokes.
Definition: geometry.cc:133