#include <geometry.h>

Inheritance diagram for impeller::Geometry:

Public Member Functions
virtual	~Geometry ()

virtual GeometryResult	GetPositionBuffer (const ContentContext &renderer, const Entity &entity, RenderPass &pass) const =0

virtual GeometryResult::Mode	GetResultMode () const

virtual std::optional< Rect >	GetCoverage (const Matrix &transform) const =0

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

Static Public Member Functions
static std::unique_ptr< Geometry >	MakeFillPath (const Path &path, std::optional< Rect > inner_rect=std::nullopt)

static std::unique_ptr< Geometry >	MakeStrokePath (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< Geometry >	MakeCover ()

static std::unique_ptr< Geometry >	MakeRect (const Rect &rect)

static std::unique_ptr< Geometry >	MakeOval (const Rect &rect)

static std::unique_ptr< Geometry >	MakeLine (const Point &p0, const Point &p1, Scalar width, Cap cap)

static std::unique_ptr< Geometry >	MakeCircle (const Point &center, Scalar radius)

static std::unique_ptr< Geometry >	MakeStrokedCircle (const Point &center, Scalar radius, Scalar stroke_width)

static std::unique_ptr< Geometry >	MakeRoundRect (const Rect &rect, const Size &radii)

static std::unique_ptr< Geometry >	MakePointField (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
static GeometryResult	ComputePositionGeometry (const ContentContext &renderer, const Tessellator::VertexGenerator &generator, const Entity &entity, RenderPass &pass)

Detailed Description

Definition at line 55 of file geometry.h.

Constructor & Destructor Documentation

◆ ~Geometry()

virtual impeller::Geometry::~Geometry ( )

inlinevirtual

Definition at line 57 of file geometry.h.

57 {}

Member Function Documentation

◆ CanApplyMaskFilter()

bool impeller::Geometry::CanApplyMaskFilter ( ) const

virtual

Reimplemented in impeller::CoverGeometry.

Definition at line 128 of file geometry.cc.

                                         {
   return true;
 }

◆ ComputeAlphaCoverage()

virtual Scalar impeller::Geometry::ComputeAlphaCoverage ( const Matrix & transform ) const

inlinevirtual

Reimplemented in impeller::StrokePathGeometry, impeller::CircleGeometry, and impeller::LineGeometry.

Definition at line 124 of file geometry.h.

                                                                      {
     return 1.0;
   }

Referenced by impeller::ColorSourceContents::AppliesAlphaForStrokeCoverage(), impeller::TiledTextureContents::Render(), and impeller::SolidColorContents::Render().

◆ ComputePositionGeometry()

GeometryResult impeller::Geometry::ComputePositionGeometry	(	const ContentContext &	renderer,
		const Tessellator::VertexGenerator &	generator,
		const Entity &	entity,
		RenderPass &	pass
	)

staticprotected

Definition at line 24 of file geometry.cc.

                       {
   using VT = SolidFillVertexShader::PerVertexData;
  
   size_t count = generator.GetVertexCount();
  
   return GeometryResult{
       .type = generator.GetTriangleType(),
       .vertex_buffer =
           {
               .vertex_buffer = renderer.GetTransientsBuffer().Emplace(
                   count * sizeof(VT), alignof(VT),
                   [&generator](uint8_t* buffer) {
                     auto vertices = reinterpret_cast<VT*>(buffer);
                     generator.GenerateVertices([&vertices](const Point& p) {
                       *vertices++ = {
                           .position = p,
                       };
                     });
                     FML_DCHECK(vertices == reinterpret_cast<VT*>(buffer) +
                                                generator.GetVertexCount());
                   }),
               .vertex_count = count,
               .index_type = IndexType::kNone,
           },
       .transform = entity.GetShaderTransform(pass),
   };
 }

References impeller::HostBuffer::Emplace(), impeller::Tessellator::VertexGenerator::GenerateVertices(), impeller::Entity::GetShaderTransform(), impeller::ContentContext::GetTransientsBuffer(), impeller::Tessellator::VertexGenerator::GetTriangleType(), impeller::Tessellator::VertexGenerator::GetVertexCount(), impeller::kNone, and impeller::GeometryResult::type.

◆ ComputeStrokeAlphaCoverage()

Scalar impeller::Geometry::ComputeStrokeAlphaCoverage	(	const Matrix &	entity,
		Scalar	stroke_width
	)

static

Compute an alpha value to simulate lower coverage of fractional pixel strokes.

Definition at line 133 of file geometry.cc.

                                                                  {
   Scalar scaled_stroke_width = transform.GetMaxBasisLengthXY() * stroke_width;
   // If the stroke width is 0 or greater than kMinStrokeSizeMSAA, don't apply
   // any additional alpha. This is intended to match Skia behavior.
   if (scaled_stroke_width == 0.0 || scaled_stroke_width >= kMinStrokeSizeMSAA) {
     return 1.0;
   }
   // This scalling is eyeballed from Skia.
   return std::clamp(scaled_stroke_width * 2.0f, 0.f, 1.f);
 }

References impeller::kMinStrokeSizeMSAA, stroke_width, and transform.

Referenced by impeller::LineGeometry::ComputeAlphaCoverage(), impeller::CircleGeometry::ComputeAlphaCoverage(), and impeller::StrokePathGeometry::ComputeAlphaCoverage().

◆ CoversArea()

bool impeller::Geometry::CoversArea	(	const Matrix &	transform,
		const Rect &	rect
	)		const

virtual

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 in impeller::SuperellipseGeometry, impeller::CircleGeometry, impeller::FillPathGeometry, impeller::EllipseGeometry, impeller::LineGeometry, impeller::RoundRectGeometry, impeller::CoverGeometry, and impeller::RectGeometry.

Definition at line 120 of file geometry.cc.

                                                                          {
   return false;
 }

Referenced by impeller::SolidColorContents::AsBackgroundColor().

◆ GetCoverage()

virtual std::optional<Rect> impeller::Geometry::GetCoverage ( const Matrix & transform ) const

pure virtual

Implemented in impeller::DlVerticesGeometry, and impeller::RectGeometry.

Referenced by impeller::ColorSourceContents::DrawGeometry(), impeller::ClipContents::GetClipCoverage(), impeller::SolidColorContents::GetCoverage(), impeller::ColorSourceContents::GetCoverage(), impeller::ClipContents::Render(), and impeller::TiledTextureContents::RenderToSnapshot().

◆ GetPositionBuffer()

virtual GeometryResult impeller::Geometry::GetPositionBuffer	(	const ContentContext &	renderer,
		const Entity &	entity,
		RenderPass &	pass
	)		const

pure virtual

Implemented in impeller::DlVerticesGeometry, and impeller::RectGeometry.

Referenced by impeller::ColorSourceContents::DefaultCreateGeometryCallback(), impeller::ColorSourceContents::DrawGeometry(), and impeller::ClipContents::Render().

◆ GetResultMode()

GeometryResult::Mode impeller::Geometry::GetResultMode ( ) const

virtual

Definition at line 56 of file geometry.cc.

                                                  {
   return GeometryResult::Mode::kNormal;
 }

References impeller::GeometryResult::kNormal.

Referenced by impeller::ColorSourceContents::DrawGeometry().

◆ IsAxisAlignedRect()

bool impeller::Geometry::IsAxisAlignedRect ( ) const

virtual

Reimplemented in impeller::SuperellipseGeometry, impeller::CircleGeometry, impeller::EllipseGeometry, impeller::LineGeometry, impeller::RoundRectGeometry, and impeller::RectGeometry.

Definition at line 124 of file geometry.cc.

                                        {
   return false;
 }

Referenced by impeller::ClipContents::GetClipCoverage().

◆ MakeCircle()

std::unique_ptr< Geometry > impeller::Geometry::MakeCircle	(	const Point &	center,
		Scalar	radius
	)

static

Definition at line 104 of file geometry.cc.

                                                               {
   return std::make_unique<CircleGeometry>(center, radius);
 }

◆ MakeCover()

std::unique_ptr< Geometry > impeller::Geometry::MakeCover ( )

static

Definition at line 85 of file geometry.cc.

                                             {
   return std::make_unique<CoverGeometry>();
 }

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

◆ MakeFillPath()

std::unique_ptr< Geometry > impeller::Geometry::MakeFillPath	(	const Path &	path,
		std::optional< Rect >	inner_rect = `std::nullopt`
	)

static

Definition at line 60 of file geometry.cc.

                                   {
   return std::make_unique<FillPathGeometry>(path, inner_rect);
 }

Referenced by impeller::DlDispatcherBase::clipPath(), impeller::DlDispatcherBase::clipRRect(), impeller::testing::TEST(), and impeller::testing::TEST_P().

◆ MakeLine()

std::unique_ptr< Geometry > impeller::Geometry::MakeLine	(	const Point &	p0,
		const Point &	p1,
		Scalar	width,
		Cap	cap
	)

static

Definition at line 97 of file geometry.cc.

                                                       {
   return std::make_unique<LineGeometry>(p0, p1, width, cap);
 }

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

◆ MakeOval()

std::unique_ptr< Geometry > impeller::Geometry::MakeOval ( const Rect & rect )

static

Definition at line 93 of file geometry.cc.

                                                            {
   return std::make_unique<EllipseGeometry>(rect);
 }

Referenced by impeller::DlDispatcherBase::clipOval(), impeller::DlDispatcherBase::clipPath(), and impeller::DlDispatcherBase::clipRRect().

◆ MakePointField()

std::unique_ptr< Geometry > impeller::Geometry::MakePointField	(	std::vector< Point >	points,
		Scalar	radius,
		bool	round
	)

static

Definition at line 66 of file geometry.cc.

                                                                {
   return std::make_unique<PointFieldGeometry>(std::move(points), radius, round);
 }

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

◆ MakeRect()

std::unique_ptr< Geometry > impeller::Geometry::MakeRect ( const Rect & rect )

static

Definition at line 89 of file geometry.cc.

                                                            {
   return std::make_unique<RectGeometry>(rect);
 }

Referenced by impeller::DlDispatcherBase::clipPath(), impeller::DlDispatcherBase::clipRect(), impeller::DlDispatcherBase::clipRRect(), impeller::Canvas::DrawVertices(), impeller::testing::TEST(), and impeller::testing::TEST_P().

◆ MakeRoundRect()

std::unique_ptr< Geometry > impeller::Geometry::MakeRoundRect	(	const Rect &	rect,
		const Size &	radii
	)

static

Definition at line 115 of file geometry.cc.

                                                                      {
   return std::make_unique<RoundRectGeometry>(rect, radii);
 }

Referenced by impeller::DlDispatcherBase::clipPath(), impeller::DlDispatcherBase::clipRRect(), and impeller::testing::TEST().

◆ MakeStrokedCircle()

std::unique_ptr< Geometry > impeller::Geometry::MakeStrokedCircle	(	const Point &	center,
		Scalar	radius,
		Scalar	stroke_width
	)

static

Definition at line 109 of file geometry.cc.

                                                                            {
   return std::make_unique<CircleGeometry>(center, radius, stroke_width);
 }

References stroke_width.

◆ MakeStrokePath()

std::unique_ptr< Geometry > impeller::Geometry::MakeStrokePath	(	const Path &	path,
		Scalar	stroke_width = `0.0`,
		Scalar	miter_limit = `4.0`,
		Cap	stroke_cap = `Cap::kButt`,
		Join	stroke_join = `Join::kMiter`
	)

static

Definition at line 72 of file geometry.cc.

                                                                      {
   // Skia behaves like this.
   if (miter_limit < 0) {
     miter_limit = 4.0;
   }
   return std::make_unique<StrokePathGeometry>(path, stroke_width, miter_limit,
                                               stroke_cap, stroke_join);
 }

References stroke_width.

Referenced by impeller::testing::TEST(), and impeller::testing::TEST_P().

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

impeller/entity/geometry/geometry.h
impeller/entity/geometry/geometry.cc

Public Member Functions

Static Public Member Functions

Static Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ ~Geometry()

Member Function Documentation

◆ CanApplyMaskFilter()

◆ ComputeAlphaCoverage()

◆ ComputePositionGeometry()

◆ ComputeStrokeAlphaCoverage()

◆ CoversArea()

◆ GetCoverage()

◆ GetPositionBuffer()

◆ GetResultMode()

◆ IsAxisAlignedRect()

◆ MakeCircle()

◆ MakeCover()

◆ MakeFillPath()

◆ MakeLine()

◆ MakeOval()

◆ MakePointField()

◆ MakeRect()

◆ MakeRoundRect()

◆ MakeStrokedCircle()

◆ MakeStrokePath()