impeller::LineGeometry Class Reference

#include <line_geometry.h>

Inheritance diagram for impeller::LineGeometry:

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

Static Public Member Functions
static Scalar	ComputePixelHalfWidth (const Matrix &transform, Scalar width)
Static Public Member Functions inherited from impeller::Geometry
static std::shared_ptr< Geometry >	MakeFillPath (Path path, std::optional< Rect > inner_rect=std::nullopt)
static std::shared_ptr< Geometry >	MakeStrokePath (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< Geometry >	MakeCover ()
static std::shared_ptr< Geometry >	MakeRect (const Rect &rect)
static std::shared_ptr< Geometry >	MakeOval (const Rect &rect)
static std::shared_ptr< Geometry >	MakeLine (const Point &p0, const Point &p1, Scalar width, Cap cap)
static std::shared_ptr< Geometry >	MakeCircle (const Point &center, Scalar radius)
static std::shared_ptr< Geometry >	MakeStrokedCircle (const Point &center, Scalar radius, Scalar stroke_width)
static std::shared_ptr< Geometry >	MakeRoundRect (const Rect &rect, const Size &radii)
static std::shared_ptr< Geometry >	MakePointField (std::vector< Point > points, Scalar radius, bool round)

Additional Inherited Members
Static Protected Member Functions inherited from impeller::Geometry
static GeometryResult	ComputePositionGeometry (const Tessellator::VertexGenerator &generator, const Entity &entity, RenderPass &pass)
static GeometryResult	ComputePositionUVGeometry (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.

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

~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.

                                                         {
  auto determinant = transform.GetDeterminant();
  if (determinant == 0) {
    return 0.0f;
  }
 
  Scalar min_size = 1.0f / sqrt(std::abs(determinant));
  return std::max(width, min_size) * 0.5f;
}

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 180 of file line_geometry.cc.

                                                                             {
  if (!transform.IsTranslationScaleOnly() || !IsAxisAlignedRect()) {
    return false;
  }
  auto coverage = GetCoverage(transform);
  return coverage.has_value() ? coverage->Contains(rect) : false;
}

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

IsAxisAlignedRect()

bool impeller::LineGeometry::IsAxisAlignedRect ( ) const

overridevirtual

Reimplemented from impeller::Geometry.

Definition at line 188 of file line_geometry.cc.

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

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

Referenced by CoversArea().

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

• impeller/entity/geometry/line_geometry.h
• impeller/entity/geometry/line_geometry.cc