| Flutter Impeller |

Public Member Functions | List of all members
impeller::DirectionalMorphologyFilterContents Class Referencefinal

`#include <morphology_filter_contents.h>`

Inheritance diagram for impeller::DirectionalMorphologyFilterContents:

## Public Member Functions
| DirectionalMorphologyFilterContents ()
| ~DirectionalMorphologyFilterContents () override
void | SetRadius (Radius radius)
void | SetDirection (Vector2 direction)
void | SetMorphType (MorphType morph_type)
std::optional< Rect > | GetFilterCoverage (const FilterInput::Vector &inputs, const Entity &entity, const Matrix &effect_transform) const override
| Internal utility method for |GetLocalCoverage| that computes the output coverage of this filter across the specified inputs, ignoring the coverage hint. More...
std::optional< Rect > | GetFilterSourceCoverage (const Matrix &effect_transform, const Rect &output_limit) const override
| Internal utility method for |GetSourceCoverage| that computes the inverse effect of this transform on the specified output coverage, ignoring the inputs which will be accommodated by the caller. More...
Public Member Functions inherited from impeller::FilterContents
| 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 area of the render pass that will be affected when this contents is rendered. 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, int32_t mip_count=1, const std::string &label="Filter Snapshot") const override
| Render this contents to a snapshot, respecting the entity's transform, path, clip 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...
std::optional< Rect > | GetSourceCoverage (const Matrix &effect_transform, const Rect &output_limit) const
| Determines the coverage of source pixels that will be needed to produce results for the specified |output_limit| under the specified |effect_transform|. This is essentially a reverse of the |GetCoverage| method computing a source coverage from an intended |output_limit| coverage. 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 transforms to the filtered content. For example: Rotating, scaling, and skewing are all basis transforms, 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 ClipCoverage | GetClipCoverage (const Entity &entity, const std::optional< Rect > &current_clip_coverage) const
| Given the current pass space bounding rectangle of the clip buffer, return the expected clip coverage after this draw call. This should only be implemented for contents that may write to the clip buffer. More...
virtual bool | ShouldRender (const Entity &entity, const std::optional< Rect > clip_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...

## Additional Inherited Members
Public Types inherited from impeller::FilterContents
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)>
Static Public Member Functions inherited from impeller::FilterContents
static std::shared_ptr< FilterContents > | MakeGaussianBlur (const FilterInput::Ref &input, Sigma sigma_x, Sigma sigma_y, Entity::TileMode tile_mode=Entity::TileMode::kDecal, BlurStyle mask_blur_style=BlurStyle::kNormal, const std::shared_ptr< Geometry > &mask_geometry=nullptr)
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)
Static Public Attributes inherited from impeller::FilterContents
static const int32_t | kBlurFilterRequiredMipCount

## Detailed Description

Definition at line 15 of file morphology_filter_contents.h.

## Constructor & Destructor Documentation

## ◆ DirectionalMorphologyFilterContents()

impeller::DirectionalMorphologyFilterContents::DirectionalMorphologyFilterContents | ( |  | ) |
| default

## ◆ ~DirectionalMorphologyFilterContents()

impeller::DirectionalMorphologyFilterContents::~DirectionalMorphologyFilterContents | ( |  | ) |
| override default

## Member Function Documentation

## ◆ GetFilterCoverage()

std::optional< Rect > impeller::DirectionalMorphologyFilterContents::GetFilterCoverage | ( | const FilterInput::Vector & | inputs,
|  | const Entity & | entity,
|  | const Matrix & | effect_transform
| ) |  | const
| override virtual

Internal utility method for |GetLocalCoverage| that computes the output coverage of this filter across the specified inputs, ignoring the coverage hint.

Reimplemented from impeller::FilterContents.

Definition at line 167 of file morphology_filter_contents.cc.

170 {
171 if (inputs.empty()) {
172 return std::nullopt;
173 }
174
175 auto coverage = inputs[0]->GetCoverage(entity);
176 if (!coverage.has_value()) {
177 return std::nullopt;
178 }
179 auto transform = inputs[0]->GetTransform(entity) * effect_transform.Basis();
180 auto transformed_vector =
181 transform.TransformDirection(direction_ * radius_.radius).Abs();
182
183 auto origin = coverage->GetOrigin();
184 auto size = Vector2(coverage->GetSize());
185 switch (morph_type_) {
186 case FilterContents::MorphType::kDilate:
187 origin -= transformed_vector;
188 size += transformed_vector * 2;
189 break;
190 case FilterContents::MorphType::kErode:
191 origin += transformed_vector;
192 size -= transformed_vector * 2;
193 break;
194 }
195 if (size.x < 0 || size.y < 0) {
196 return Rect::MakeSize(Size(0, 0));
197 }
198 return Rect::MakeOriginSize(origin, Size(size.x, size.y));
199 }

References impeller::Matrix::Basis(), impeller::TRect< T >::GetOrigin(), impeller::TRect< T >::GetSize(), impeller::FilterContents::kDilate, impeller::FilterContents::kErode, impeller::TRect< Scalar >::MakeOriginSize(), impeller::TRect< Scalar >::MakeSize(), impeller::Radius::radius, and transform.

## ◆ GetFilterSourceCoverage()

std::optional< Rect > impeller::DirectionalMorphologyFilterContents::GetFilterSourceCoverage | ( | const Matrix & | effect_transform,
|  | const Rect & | output_limit
| ) |  | const
| override virtual

Internal utility method for |GetSourceCoverage| that computes the inverse effect of this transform on the specified output coverage, ignoring the inputs which will be accommodated by the caller.

Implements impeller::FilterContents.

Definition at line 202 of file morphology_filter_contents.cc.

204 {
205 auto transformed_vector =
206 effect_transform.TransformDirection(direction_ * radius_.radius).Abs();
207 switch (morph_type_) {
208 case FilterContents::MorphType::kDilate:
209 return output_limit.Expand(-transformed_vector);
210 case FilterContents::MorphType::kErode:
211 return output_limit.Expand(transformed_vector);
212 }
213 }

References impeller::TRect< T >::Expand(), impeller::FilterContents::kDilate, impeller::FilterContents::kErode, impeller::Radius::radius, and impeller::Matrix::TransformDirection().

## ◆ SetDirection()

void impeller::DirectionalMorphologyFilterContents::SetDirection | ( | Vector2 | direction | ) |

Definition at line 27 of file morphology_filter_contents.cc.

27 {
28 direction_ = direction.Normalize();
29 if (direction_.IsZero()) {
30 direction_ = Vector2(0, 1);
31 }
32 }

References impeller::TPoint< T >::IsZero(), and impeller::TPoint< T >::Normalize().

## ◆ SetMorphType()

void impeller::DirectionalMorphologyFilterContents::SetMorphType | ( | MorphType | morph_type | ) |

Definition at line 34 of file morphology_filter_contents.cc.

34 {
35 morph_type_ = morph_type;
36 }

## ◆ SetRadius()

void impeller::DirectionalMorphologyFilterContents::SetRadius | ( | Radius | radius | ) |

Definition at line 23 of file morphology_filter_contents.cc.

23 {
24 radius_ = radius;
25 }

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

- impeller/entity/contents/filters/morphology_filter_contents.h
- impeller/entity/contents/filters/morphology_filter_contents.cc

impeller::Radius::radius
Scalar radius
Definition: sigma.h:49
impeller::FilterContents::MorphType::kErode
@ kErode
impeller::Vector2
Point Vector2
Definition: point.h:326
impeller::Size
TSize< Scalar > Size
Definition: size.h:137
impeller::TPoint::IsZero
constexpr bool IsZero() const
Definition: point.h:240
transform
Matrix transform
Definition: gaussian_blur_filter_contents.cc:231
impeller::TRect< Scalar >::MakeOriginSize
constexpr static TRect MakeOriginSize(const TPoint< Type > &origin, const TSize< Type > &size)
Definition: rect.h:140
impeller::TRect< Scalar >::MakeSize
constexpr static TRect MakeSize(const TSize< U > &size)
Definition: rect.h:146
impeller::FilterContents::MorphType::kDilate
@ kDilate
impeller::TPoint::Normalize
constexpr TPoint Normalize() const
Definition: point.h:208