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impeller::EllipseGeometry Class Referencefinal

A Geometry class that can directly generate vertices (with or without texture coordinates) for filled ellipses. More...

#include <ellipse_geometry.h>

Inheritance diagram for impeller::EllipseGeometry:
impeller::Geometry

Public Member Functions

 EllipseGeometry (Rect bounds)
 
 ~EllipseGeometry () override=default
 
bool CoversArea (const Matrix &transform, const IRect &rect) const override
 Determines if this geometry, transformed by the given transform, will completely cover all of the pixels within the given integer rect.
 
bool IsAxisAlignedRect () const override
 
- Public Member Functions inherited from impeller::Geometry
virtual ~Geometry ()
 
virtual GeometryResult::Mode GetResultMode () 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.
 
static GeometryResult ComputePositionGeometry (const ContentContext &renderer, const Tessellator::VertexGenerator &generator, const Entity &entity, RenderPass &pass)
 

Detailed Description

A Geometry class that can directly generate vertices (with or without texture coordinates) for filled ellipses.

Generating vertices for a stroked ellipse would require a lot more work since the line width must be applied perpendicular to the distorted ellipse shape.

See also
|StrokeEllipseGeometry|

Definition at line 21 of file ellipse_geometry.h.

Constructor & Destructor Documentation

◆ EllipseGeometry()

impeller::EllipseGeometry::EllipseGeometry ( Rect  bounds)
explicit

Definition at line 13 of file ellipse_geometry.cc.

13: bounds_(bounds) {}

◆ ~EllipseGeometry()

impeller::EllipseGeometry::~EllipseGeometry ( )
overridedefault

Member Function Documentation

◆ CoversArea()

bool impeller::EllipseGeometry::CoversArea ( const Matrix transform,
const IRect rect 
) const
overridevirtual

Determines if this geometry, transformed by the given transform, will completely cover all of the pixels within the given integer rect.

The integer rect, by definition, will contain all of the area covered by any pixel within its boundary.

The return value can be a conservative estimate which will still be useful for certain optimizations. It may return false for obscure cases that might actually contain all of the pixels if it is too computationally costly to prove containment, but it should never return 'true' unless the implementation can prove that all pixels are fully covered (rendered) by the geometry.

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

Reimplemented from impeller::Geometry.

Definition at line 30 of file ellipse_geometry.cc.

31 {
32 return false;
33}

◆ IsAxisAlignedRect()

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

Reimplemented from impeller::Geometry.

Definition at line 35 of file ellipse_geometry.cc.

35 {
36 return false;
37}

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