#include <filter_contents.h>

Inheritance diagram for impeller::FilterContents:

Public Types
enum	BlurStyle { BlurStyle::kNormal, BlurStyle::kSolid, BlurStyle::kOuter, BlurStyle::kInner }

enum	MorphType { MorphType::kDilate, MorphType::kErode }

Public Types inherited from impeller::Contents
using	ColorFilterProc = std::function< Color(Color)>

using	RenderProc = std::function< bool(const ContentContext &renderer, const Entity &entity, RenderPass &pass)>

using	CoverageProc = std::function< std::optional< Rect >(const Entity &entity)>

Public Member Functions
	FilterContents ()

	~FilterContents () override

void	SetInputs (FilterInput::Vector inputs)
	The input texture sources for this filter. Each input's emitted texture is expected to have premultiplied alpha colors. More...

void	SetEffectTransform (const Matrix &effect_transform)
	Sets the transform which gets appended to the effect of this filter. Note that this is in addition to the entity's transform. More...

std::optional< Entity >	GetEntity (const ContentContext &renderer, const Entity &entity, const std::optional< Rect > &coverage_hint) const
	Create an Entity that renders this filter's output. More...

bool	Render (const ContentContext &renderer, const Entity &entity, RenderPass &pass) const override

std::optional< Rect >	GetCoverage (const Entity &entity) const override
	Get the screen space bounding rectangle that this contents affects. More...

void	PopulateGlyphAtlas (const std::shared_ptr< LazyGlyphAtlas > &lazy_glyph_atlas, Scalar scale) override
	Add any text data to the specified lazy atlas. The scale parameter must be used again later when drawing the text. More...

std::optional< Snapshot >	RenderToSnapshot (const ContentContext &renderer, const Entity &entity, std::optional< Rect > coverage_limit=std::nullopt, const std::optional< SamplerDescriptor > &sampler_descriptor=std::nullopt, bool msaa_enabled=true, const std::string &label="Filter Snapshot") const override
	Render this contents to a snapshot, respecting the entity's transform, path, stencil depth, and blend mode. The result texture size is always the size of `GetCoverage(entity)`. More...

const FilterContents *	AsFilter () const override
	Cast to a filter. Returns `nullptr` if this Contents is not a filter. More...

virtual Matrix	GetLocalTransform (const Matrix &parent_transform) const

Matrix	GetTransform (const Matrix &parent_transform) const

virtual bool	IsTranslationOnly () const
	Returns true if this filter graph doesn't perform any basis transformations to the filtered content. For example: Rotating, scaling, and skewing are all basis transformations, but translating is not. More...

bool	IsLeaf () const
	Returns `true` if this filter does not have any `FilterInput` children. More...

void	SetLeafInputs (const FilterInput::Vector &inputs)
	Replaces the set of all leaf `FilterContents` with a new set of `FilterInput`s. More...

virtual void	SetRenderingMode (Entity::RenderingMode rendering_mode)
	Marks this filter chain as applying in a subpass scenario. More...

Public Member Functions inherited from impeller::Contents
	Contents ()

virtual	~Contents ()

void	SetCoverageHint (std::optional< Rect > coverage_hint)
	Hint that specifies the coverage area of this Contents that will actually be used during rendering. This is for optimization purposes only and can not be relied on as a clip. May optionally affect the result of `GetCoverage()`. More...

const std::optional< Rect > &	GetCoverageHint () const

virtual bool	IsOpaque () const
	Whether this Contents only emits opaque source colors from the fragment stage. This value does not account for any entity properties (e.g. the blend mode), clips/visibility culling, or inherited opacity. More...

virtual StencilCoverage	GetStencilCoverage (const Entity &entity, const std::optional< Rect > &current_stencil_coverage) const
	Given the current screen space bounding rectangle of the stencil, return the expected stencil coverage after this draw call. This should only be implemented for contents that may write to the stencil buffer. More...

virtual bool	ShouldRender (const Entity &entity, const std::optional< Rect > &stencil_coverage) const

std::optional< Size >	GetColorSourceSize () const
	Return the color source's intrinsic size, if available. More...

void	SetColorSourceSize (Size size)

virtual bool	CanInheritOpacity (const Entity &entity) const
	Whether or not this contents can accept the opacity peephole optimization. More...

virtual void	SetInheritedOpacity (Scalar opacity)
	Inherit the provided opacity. More...

virtual std::optional< Color >	AsBackgroundColor (const Entity &entity, ISize target_size) const
	Returns a color if this Contents will flood the given `target_size` with a color. This output color is the "Source" color that will be used for the Entity's blend operation. More...

virtual bool	ApplyColorFilter (const ColorFilterProc &color_filter_proc)
	If possible, applies a color filter to this contents inputs on the CPU. More...

Static Public Member Functions
static std::shared_ptr< FilterContents >	MakeDirectionalGaussianBlur (FilterInput::Ref input, Sigma sigma, Vector2 direction, BlurStyle blur_style=BlurStyle::kNormal, Entity::TileMode tile_mode=Entity::TileMode::kDecal, bool is_second_pass=false, Sigma secondary_sigma={})

static std::shared_ptr< FilterContents >	MakeGaussianBlur (const FilterInput::Ref &input, Sigma sigma_x, Sigma sigma_y, BlurStyle blur_style=BlurStyle::kNormal, Entity::TileMode tile_mode=Entity::TileMode::kDecal)

static std::shared_ptr< FilterContents >	MakeBorderMaskBlur (FilterInput::Ref input, Sigma sigma_x, Sigma sigma_y, BlurStyle blur_style=BlurStyle::kNormal)

static std::shared_ptr< FilterContents >	MakeDirectionalMorphology (FilterInput::Ref input, Radius radius, Vector2 direction, MorphType morph_type)

static std::shared_ptr< FilterContents >	MakeMorphology (FilterInput::Ref input, Radius radius_x, Radius radius_y, MorphType morph_type)

static std::shared_ptr< FilterContents >	MakeMatrixFilter (FilterInput::Ref input, const Matrix &matrix, const SamplerDescriptor &desc)

static std::shared_ptr< FilterContents >	MakeLocalMatrixFilter (FilterInput::Ref input, const Matrix &matrix)

static std::shared_ptr< FilterContents >	MakeYUVToRGBFilter (std::shared_ptr< Texture > y_texture, std::shared_ptr< Texture > uv_texture, YUVColorSpace yuv_color_space)

Static Public Member Functions inherited from impeller::Contents
static std::shared_ptr< Contents >	MakeAnonymous (RenderProc render_proc, CoverageProc coverage_proc)

Detailed Description

Definition at line 19 of file filter_contents.h.

Member Enumeration Documentation

◆ BlurStyle

enum impeller::FilterContents::BlurStyle

strong

Enumerator
kNormal	Blurred inside and outside.
kSolid	Solid inside, blurred outside.
kOuter	Nothing inside, blurred outside.
kInner	Blurred inside, nothing outside.

Definition at line 21 of file filter_contents.h.

                        {
     /// Blurred inside and outside.
     kNormal,
     /// Solid inside, blurred outside.
     kSolid,
     /// Nothing inside, blurred outside.
     kOuter,
     /// Blurred inside, nothing outside.
     kInner,
   };

◆ MorphType

enum impeller::FilterContents::MorphType

strong

Enumerator
kDilate
kErode

Definition at line 32 of file filter_contents.h.

32 { kDilate, kErode };

Constructor & Destructor Documentation

◆ FilterContents()

impeller::FilterContents::FilterContents ( )

default

◆ ~FilterContents()

impeller::FilterContents::~FilterContents ( )

overridedefault

Member Function Documentation

◆ AsFilter()

const FilterContents * impeller::FilterContents::AsFilter ( ) const

overridevirtual

Cast to a filter. Returns nullptr if this Contents is not a filter.

Reimplemented from impeller::Contents.

Definition at line 262 of file filter_contents.cc.

                                                      {
   return this;
 }

◆ GetCoverage()

std::optional< Rect > impeller::FilterContents::GetCoverage ( const Entity & entity ) const

overridevirtual

Get the screen space bounding rectangle that this contents affects.

Implements impeller::Contents.

Definition at line 178 of file filter_contents.cc.

                                                                         {
   Entity entity_with_local_transform = entity;
   entity_with_local_transform.SetTransformation(
       GetTransform(entity.GetTransformation()));
  
   return GetLocalCoverage(entity_with_local_transform);
 }

References GetTransform(), impeller::Entity::GetTransformation(), and impeller::Entity::SetTransformation().

Referenced by Render().

◆ GetEntity()

std::optional< Entity > impeller::FilterContents::GetEntity	(	const ContentContext &	renderer,
		const Entity &	entity,
		const std::optional< Rect > &	coverage_hint
	)		const

Create an Entity that renders this filter's output.

Definition at line 221 of file filter_contents.cc.

                                                   {
   Entity entity_with_local_transform = entity;
   entity_with_local_transform.SetTransformation(
       GetTransform(entity.GetTransformation()));
  
   auto coverage = GetLocalCoverage(entity_with_local_transform);
   if (!coverage.has_value() || coverage->IsEmpty()) {
     return std::nullopt;
   }
  
   return RenderFilter(inputs_, renderer, entity_with_local_transform,
                       effect_transform_, coverage.value(), coverage_hint);
 }

References GetTransform(), impeller::Entity::GetTransformation(), and impeller::Entity::SetTransformation().

Referenced by Render(), and RenderToSnapshot().

◆ GetLocalTransform()

Matrix impeller::FilterContents::GetLocalTransform ( const Matrix & parent_transform ) const

virtual

Reimplemented in impeller::LocalMatrixFilterContents.

Definition at line 266 of file filter_contents.cc.

                                                                              {
   return Matrix();
 }

Referenced by GetTransform().

◆ GetTransform()

Matrix impeller::FilterContents::GetTransform ( const Matrix & parent_transform ) const

Definition at line 270 of file filter_contents.cc.

                                                                         {
   return parent_transform * GetLocalTransform(parent_transform);
 }

References GetLocalTransform().

Referenced by GetCoverage(), and GetEntity().

◆ IsLeaf()

bool impeller::FilterContents::IsLeaf ( ) const

Returns true if this filter does not have any FilterInput children.

Definition at line 282 of file filter_contents.cc.

                                   {
   for (auto& input : inputs_) {
     if (!input->IsLeaf()) {
       return false;
     }
   }
   return true;
 }

Referenced by SetLeafInputs().

◆ IsTranslationOnly()

bool impeller::FilterContents::IsTranslationOnly ( ) const

virtual

Returns true if this filter graph doesn't perform any basis transformations to the filtered content. For example: Rotating, scaling, and skewing are all basis transformations, but translating is not.

This is useful for determining whether a filtered object's space is compatible enough with the parent pass space to perform certain subpass clipping optimizations.

Reimplemented in impeller::MatrixFilterContents.

Definition at line 273 of file filter_contents.cc.

                                              {
   for (auto& input : inputs_) {
     if (!input->IsTranslationOnly()) {
       return false;
     }
   }
   return true;
 }

Referenced by impeller::MatrixFilterContents::IsTranslationOnly().

◆ MakeBorderMaskBlur()

std::shared_ptr< FilterContents > impeller::FilterContents::MakeBorderMaskBlur	(	FilterInput::Ref	input,
		Sigma	sigma_x,
		Sigma	sigma_y,
		BlurStyle	blur_style = `BlurStyle::kNormal`
	)

static

Definition at line 66 of file filter_contents.cc.

                           {
   auto filter = std::make_shared<BorderMaskBlurFilterContents>();
   filter->SetInputs({std::move(input)});
   filter->SetSigma(sigma_x, sigma_y);
   filter->SetBlurStyle(blur_style);
   return filter;
 }

Referenced by impeller::Paint::MaskBlurDescriptor::CreateMaskBlur(), and impeller::testing::TEST_P().

◆ MakeDirectionalGaussianBlur()

std::shared_ptr< FilterContents > impeller::FilterContents::MakeDirectionalGaussianBlur	(	FilterInput::Ref	input,
		Sigma	sigma,
		Vector2	direction,
		BlurStyle	blur_style = `BlurStyle::kNormal`,
		Entity::TileMode	tile_mode = `Entity::TileMode::kDecal`,
		bool	is_second_pass = `false`,
		Sigma	secondary_sigma = `{}`
	)

static

Definition at line 33 of file filter_contents.cc.

                            {
   auto blur = std::make_shared<DirectionalGaussianBlurFilterContents>();
   blur->SetInputs({std::move(input)});
   blur->SetSigma(sigma);
   blur->SetDirection(direction);
   blur->SetBlurStyle(blur_style);
   blur->SetTileMode(tile_mode);
   blur->SetIsSecondPass(is_second_pass);
   blur->SetSecondarySigma(secondary_sigma);
   return blur;
 }

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

◆ MakeDirectionalMorphology()

std::shared_ptr< FilterContents > impeller::FilterContents::MakeDirectionalMorphology	(	FilterInput::Ref	input,
		Radius	radius,
		Vector2	direction,
		MorphType	morph_type
	)

static

Definition at line 78 of file filter_contents.cc.

                           {
   auto filter = std::make_shared<DirectionalMorphologyFilterContents>();
   filter->SetInputs({std::move(input)});
   filter->SetRadius(radius);
   filter->SetDirection(direction);
   filter->SetMorphType(morph_type);
   return filter;
 }

Referenced by MakeMorphology().

◆ MakeGaussianBlur()

std::shared_ptr< FilterContents > impeller::FilterContents::MakeGaussianBlur	(	const FilterInput::Ref &	input,
		Sigma	sigma_x,
		Sigma	sigma_y,
		BlurStyle	blur_style = `BlurStyle::kNormal`,
		Entity::TileMode	tile_mode = `Entity::TileMode::kDecal`
	)

static

Definition at line 52 of file filter_contents.cc.

                               {
   auto x_blur = MakeDirectionalGaussianBlur(
       input, sigma_x, Point(1, 0), BlurStyle::kNormal, tile_mode, false, {});
   auto y_blur = MakeDirectionalGaussianBlur(FilterInput::Make(x_blur), sigma_y,
                                             Point(0, 1), blur_style, tile_mode,
                                             true, sigma_x);
   return y_blur;
 }

References kNormal, impeller::FilterInput::Make(), and MakeDirectionalGaussianBlur().

Referenced by impeller::Paint::MaskBlurDescriptor::CreateMaskBlur(), impeller::testing::TEST_P(), and impeller::BlurImageFilter::WrapInput().

◆ MakeLocalMatrixFilter()

std::shared_ptr< FilterContents > impeller::FilterContents::MakeLocalMatrixFilter	(	FilterInput::Ref	input,
		const Matrix &	matrix
	)

static

Definition at line 114 of file filter_contents.cc.

                           {
   auto filter = std::make_shared<LocalMatrixFilterContents>();
   filter->SetInputs({std::move(input)});
   filter->SetMatrix(matrix);
   return filter;
 }

Referenced by impeller::LocalMatrixImageFilter::WrapInput().

◆ MakeMatrixFilter()

std::shared_ptr< FilterContents > impeller::FilterContents::MakeMatrixFilter	(	FilterInput::Ref	input,
		const Matrix &	matrix,
		const SamplerDescriptor &	desc
	)

static

Definition at line 103 of file filter_contents.cc.

                                    {
   auto filter = std::make_shared<MatrixFilterContents>();
   filter->SetInputs({std::move(input)});
   filter->SetMatrix(matrix);
   filter->SetSamplerDescriptor(desc);
   return filter;
 }

Referenced by impeller::testing::TEST(), and impeller::MatrixImageFilter::WrapInput().

◆ MakeMorphology()

std::shared_ptr< FilterContents > impeller::FilterContents::MakeMorphology	(	FilterInput::Ref	input,
		Radius	radius_x,
		Radius	radius_y,
		MorphType	morph_type
	)

static

Definition at line 91 of file filter_contents.cc.

                           {
   auto x_morphology = MakeDirectionalMorphology(std::move(input), radius_x,
                                                 Point(1, 0), morph_type);
   auto y_morphology = MakeDirectionalMorphology(
       FilterInput::Make(x_morphology), radius_y, Point(0, 1), morph_type);
   return y_morphology;
 }

References impeller::FilterInput::Make(), and MakeDirectionalMorphology().

Referenced by impeller::testing::TEST_P(), impeller::DilateImageFilter::WrapInput(), and impeller::ErodeImageFilter::WrapInput().

◆ MakeYUVToRGBFilter()

std::shared_ptr< FilterContents > impeller::FilterContents::MakeYUVToRGBFilter	(	std::shared_ptr< Texture >	y_texture,
		std::shared_ptr< Texture >	uv_texture,
		YUVColorSpace	yuv_color_space
	)

static

Definition at line 123 of file filter_contents.cc.

                                    {
   auto filter = std::make_shared<impeller::YUVToRGBFilterContents>();
   filter->SetInputs({impeller::FilterInput::Make(y_texture),
                      impeller::FilterInput::Make(uv_texture)});
   filter->SetYUVColorSpace(yuv_color_space);
   return filter;
 }

References impeller::FilterInput::Make().

Referenced by impeller::DlImageImpeller::MakeFromYUVTextures(), and impeller::testing::TEST_P().

◆ PopulateGlyphAtlas()

void impeller::FilterContents::PopulateGlyphAtlas	(	const std::shared_ptr< LazyGlyphAtlas > &	lazy_glyph_atlas,
		Scalar	scale
	)

overridevirtual

Add any text data to the specified lazy atlas. The scale parameter must be used again later when drawing the text.

Reimplemented from impeller::Contents.

Definition at line 186 of file filter_contents.cc.

                   {
   for (auto& input : inputs_) {
     input->PopulateGlyphAtlas(lazy_glyph_atlas, scale);
   }
 }

◆ Render()

bool impeller::FilterContents::Render	(	const ContentContext &	renderer,
		const Entity &	entity,
		RenderPass &	pass
	)		const

overridevirtual

Implements impeller::Contents.

Definition at line 150 of file filter_contents.cc.

                                                     {
   auto filter_coverage = GetCoverage(entity);
   if (!filter_coverage.has_value()) {
     return true;
   }
  
   // Run the filter.
  
   auto maybe_entity = GetEntity(renderer, entity, GetCoverageHint());
   if (!maybe_entity.has_value()) {
     return true;
   }
   return maybe_entity->Render(renderer, pass);
 }

References GetCoverage(), impeller::Contents::GetCoverageHint(), and GetEntity().

◆ RenderToSnapshot()

std::optional< Snapshot > impeller::FilterContents::RenderToSnapshot	(	const ContentContext &	renderer,
		const Entity &	entity,
		std::optional< Rect >	coverage_limit = `std::nullopt`,
		const std::optional< SamplerDescriptor > &	sampler_descriptor = `std::nullopt`,
		bool	msaa_enabled = `true`,
		const std::string &	label = `"Filter Snapshot"`
	)		const

overridevirtual

Render this contents to a snapshot, respecting the entity's transform, path, stencil depth, and blend mode. The result texture size is always the size of GetCoverage(entity).

Reimplemented from impeller::Contents.

Definition at line 238 of file filter_contents.cc.

                                   {
   // Resolve the render instruction (entity) from the filter and render it to a
   // snapshot.
   if (std::optional<Entity> result =
           GetEntity(renderer, entity, coverage_limit);
       result.has_value()) {
     return result->GetContents()->RenderToSnapshot(
         renderer,        // renderer
         result.value(),  // entity
         coverage_limit,  // coverage_limit
         std::nullopt,    // sampler_descriptor
         true,            // msaa_enabled
         label);          // label
   }
  
   return std::nullopt;
 }

References GetEntity().

◆ SetEffectTransform()

void impeller::FilterContents::SetEffectTransform ( const Matrix & effect_transform )

Sets the transform which gets appended to the effect of this filter. Note that this is in addition to the entity's transform.

This is useful for subpass rendering scenarios where it's difficult to encode the current transform of the layer into the Entity being rendered.

Definition at line 142 of file filter_contents.cc.

                                                                       {
   effect_transform_ = effect_transform;
  
   for (auto& input : inputs_) {
     input->SetEffectTransform(effect_transform);
   }
 }

◆ SetInputs()

void impeller::FilterContents::SetInputs ( FilterInput::Vector inputs )

The input texture sources for this filter. Each input's emitted texture is expected to have premultiplied alpha colors.

The number of required or optional textures depends on the particular filter's implementation.

Definition at line 138 of file filter_contents.cc.

                                                        {
   inputs_ = std::move(inputs);
 }

◆ SetLeafInputs()

void impeller::FilterContents::SetLeafInputs ( const FilterInput::Vector & inputs )

Replaces the set of all leaf FilterContents with a new set of FilterInputs.

See also: FilterContents::IsLeaf

Definition at line 291 of file filter_contents.cc.

                                                                   {
   if (IsLeaf()) {
     inputs_ = inputs;
     return;
   }
   for (auto& input : inputs_) {
     input->SetLeafInputs(inputs);
   }
 }

References IsLeaf().

◆ SetRenderingMode()

void impeller::FilterContents::SetRenderingMode ( Entity::RenderingMode rendering_mode )

virtual

Marks this filter chain as applying in a subpass scenario.

    Subpasses render in screenspace, and this setting informs filters
    that the current transformation matrix of the entity is not stored
    in the Entity transformation matrix. Instead, the effect transform
    is used in this case.

Reimplemented in impeller::MatrixFilterContents.

Definition at line 301 of file filter_contents.cc.

                                                                         {
   for (auto& input : inputs_) {
     input->SetRenderingMode(rendering_mode);
   }
 }

Referenced by impeller::MatrixFilterContents::SetRenderingMode().

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

impeller/entity/contents/filters/filter_contents.h
impeller/entity/contents/filters/filter_contents.cc

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Enumeration Documentation

◆ BlurStyle

◆ MorphType

Constructor & Destructor Documentation

◆ FilterContents()

◆ ~FilterContents()

Member Function Documentation

◆ AsFilter()

◆ GetCoverage()

◆ GetEntity()

◆ GetLocalTransform()

◆ GetTransform()

◆ IsLeaf()

◆ IsTranslationOnly()

◆ MakeBorderMaskBlur()

◆ MakeDirectionalGaussianBlur()

◆ MakeDirectionalMorphology()

◆ MakeGaussianBlur()

◆ MakeLocalMatrixFilter()

◆ MakeMatrixFilter()

◆ MakeMorphology()

◆ MakeYUVToRGBFilter()

◆ PopulateGlyphAtlas()

◆ Render()

◆ RenderToSnapshot()

◆ SetEffectTransform()

◆ SetInputs()

◆ SetLeafInputs()

◆ SetRenderingMode()