Flutter Impeller
impeller::LineGeometry Class Referencefinal

#include <line_geometry.h>

Inheritance diagram for impeller::LineGeometry:
impeller::Geometry

Public Member Functions

 LineGeometry (Point p0, Point p1, Scalar width, Cap cap)
 
 ~LineGeometry ()=default
 
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
 
- Public Member Functions inherited from impeller::Geometry
virtual GeometryResult::Mode GetResultMode () const
 
virtual bool CanApplyMaskFilter () const
 

Static Public Member Functions

static Scalar ComputePixelHalfWidth (const Matrix &transform, Scalar width)
 
- Static Public Member Functions inherited from impeller::Geometry
static std::shared_ptr< GeometryMakeFillPath (const Path &path, std::optional< Rect > inner_rect=std::nullopt)
 
static std::shared_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::shared_ptr< GeometryMakeCover ()
 
static std::shared_ptr< GeometryMakeRect (const Rect &rect)
 
static std::shared_ptr< GeometryMakeOval (const Rect &rect)
 
static std::shared_ptr< GeometryMakeLine (const Point &p0, const Point &p1, Scalar width, Cap cap)
 
static std::shared_ptr< GeometryMakeCircle (const Point &center, Scalar radius)
 
static std::shared_ptr< GeometryMakeStrokedCircle (const Point &center, Scalar radius, Scalar stroke_width)
 
static std::shared_ptr< GeometryMakeRoundRect (const Rect &rect, const Size &radii)
 
static std::shared_ptr< GeometryMakePointField (std::vector< Point > points, Scalar radius, bool round)
 

Additional Inherited Members

- Static Protected Member Functions inherited from impeller::Geometry
static GeometryResult ComputePositionGeometry (const ContentContext &renderer, const Tessellator::VertexGenerator &generator, const Entity &entity, RenderPass &pass)
 
static GeometryResult ComputePositionUVGeometry (const ContentContext &renderer, const Tessellator::VertexGenerator &generator, const Matrix &uv_transform, const Entity &entity, RenderPass &pass)
 

Detailed Description

Definition at line 13 of file line_geometry.h.

Constructor & Destructor Documentation

◆ LineGeometry()

impeller::LineGeometry::LineGeometry ( Point  p0,
Point  p1,
Scalar  width,
Cap  cap 
)
explicit

Definition at line 9 of file line_geometry.cc.

10  : p0_(p0), p1_(p1), width_(width), cap_(cap) {
11  FML_DCHECK(width >= 0);
12 }

◆ ~LineGeometry()

impeller::LineGeometry::~LineGeometry ( )
default

Member Function Documentation

◆ ComputePixelHalfWidth()

Scalar impeller::LineGeometry::ComputePixelHalfWidth ( const Matrix transform,
Scalar  width 
)
static

Definition at line 14 of file line_geometry.cc.

15  {
16  auto determinant = transform.GetDeterminant();
17  if (determinant == 0) {
18  return 0.0f;
19  }
20 
21  Scalar min_size = 1.0f / sqrt(std::abs(determinant));
22  return std::max(width, min_size) * 0.5f;
23 }

References impeller::Matrix::GetDeterminant().

◆ CoversArea()

bool impeller::LineGeometry::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 179 of file line_geometry.cc.

179  {
180  if (!transform.IsTranslationScaleOnly() || !IsAxisAlignedRect()) {
181  return false;
182  }
183  auto coverage = GetCoverage(transform);
184  return coverage.has_value() ? coverage->Contains(rect) : false;
185 }

References IsAxisAlignedRect(), and impeller::Matrix::IsTranslationScaleOnly().

◆ IsAxisAlignedRect()

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

Reimplemented from impeller::Geometry.

Definition at line 187 of file line_geometry.cc.

187  {
188  return cap_ != Cap::kRound && (p0_.x == p1_.x || p0_.y == p1_.y);
189 }

References impeller::kRound, impeller::TPoint< T >::x, and impeller::TPoint< T >::y.

Referenced by CoversArea().


The documentation for this class was generated from the following files:
impeller::Cap::kRound
@ kRound
impeller::TPoint::y
Type y
Definition: point.h:31
impeller::Scalar
float Scalar
Definition: scalar.h:18
impeller::LineGeometry::IsAxisAlignedRect
bool IsAxisAlignedRect() const override
Definition: line_geometry.cc:187
impeller::TPoint::x
Type x
Definition: point.h:30