| Flutter Impeller |

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

`#include <texture_contents.h>`

Inheritance diagram for impeller::TextureContents:

## Public Member Functions
| TextureContents ()
| ~TextureContents () override
void | SetLabel (std::string label)
void | SetDestinationRect (Rect rect)
void | SetTexture (std::shared_ptr< Texture > texture)
std::shared_ptr< Texture > | GetTexture () const
void | SetSamplerDescriptor (SamplerDescriptor desc)
const SamplerDescriptor & | GetSamplerDescriptor () const
void | SetSourceRect (const Rect &source_rect)
const Rect & | GetSourceRect () const
void | SetOpacity (Scalar opacity)
Scalar | GetOpacity () const
void | SetStencilEnabled (bool enabled)
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...
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="Texture 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...
bool | Render (const ContentContext &renderer, const Entity &entity, RenderPass &pass) const override
bool | CanInheritOpacity (const Entity &entity) const override
| Whether or not this contents can accept the opacity peephole optimization. More...
void | SetInheritedOpacity (Scalar opacity) override
| Inherit the provided opacity. More...
void | SetDeferApplyingOpacity (bool defer_applying_opacity)
Public Member Functions inherited from impeller::Contents
| Contents ()
virtual | ~Contents ()
virtual void | PopulateGlyphAtlas (const std::shared_ptr< LazyGlyphAtlas > &lazy_glyph_atlas, Scalar scale)
| Add any text data to the specified lazy atlas. The scale parameter must be used again later when drawing the text. More...
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 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 const FilterContents * | AsFilter () const
| Cast to a filter. Returns `nullptr` if this Contents is not a filter. 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< TextureContents > | MakeRect (Rect destination)
| A common case factory that marks the texture contents as having a destination rectangle. In this situation, a subpass can be avoided when image filters are applied. More...
Static Public Member Functions inherited from impeller::Contents
static std::shared_ptr< Contents > | MakeAnonymous (RenderProc render_proc, CoverageProc coverage_proc)

## Additional Inherited Members
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)>

## Detailed Description

Definition at line 21 of file texture_contents.h.

## Constructor & Destructor Documentation

## ◆ TextureContents()

impeller::TextureContents::TextureContents | ( |  | ) |
| default

## ◆ ~TextureContents()

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

## Member Function Documentation

## ◆ CanInheritOpacity()

bool impeller::TextureContents::CanInheritOpacity | ( | const Entity & | entity | ) | const
| override virtual

Whether or not this contents can accept the opacity peephole optimization.

By default all contents return false. Contents are responsible for determining whether or not their own geometries intersect in a way that makes accepting opacity impossible. It is always safe to return false, especially if computing overlap would be computationally expensive.

Reimplemented from impeller::Contents.

Definition at line 57 of file texture_contents.cc.

57 {
58 return true;
59 }

## ◆ GetCoverage()

std::optional< Rect > impeller::TextureContents::GetCoverage | ( | const Entity & | entity | ) | const
| override virtual

Get the area of the render pass that will be affected when this contents is rendered.

During rendering, coverage coordinates count pixels from the top left corner of the framebuffer.

Returns
  The coverage rectangle. An `std::nullopt` result means that rendering this contents has no effect on the output color.

Implements impeller::Contents.

Definition at line 69 of file texture_contents.cc.

69 {
70 if (GetOpacity() == 0) {
71 return std::nullopt;
72 }
73 return destination_rect_.TransformBounds(entity.GetTransform());
74 };

References GetOpacity(), impeller::Entity::GetTransform(), and impeller::TRect< T >::TransformBounds().

## ◆ GetOpacity()

Scalar impeller::TextureContents::GetOpacity | ( |  | ) | const

Definition at line 65 of file texture_contents.cc.

65 {
66 return opacity_ * inherited_opacity_;
67 }

Referenced by GetCoverage(), Render(), and RenderToSnapshot().

## ◆ GetSamplerDescriptor()

const SamplerDescriptor & impeller::TextureContents::GetSamplerDescriptor | ( |  | ) | const

Definition at line 203 of file texture_contents.cc.

203 {
204 return sampler_descriptor_;
205 }

## ◆ GetSourceRect()

const Rect & impeller::TextureContents::GetSourceRect | ( |  | ) | const

Definition at line 195 of file texture_contents.cc.

195 {
196 return source_rect_;
197 }

## ◆ GetTexture()

std::shared_ptr< Texture > impeller::TextureContents::GetTexture | ( |  | ) | const

Definition at line 45 of file texture_contents.cc.

45 {
46 return texture_;
47 }

## ◆ MakeRect()

std::shared_ptr< TextureContents > impeller::TextureContents::MakeRect | ( | Rect | destination | ) |
| static

A common case factory that marks the texture contents as having a destination rectangle. In this situation, a subpass can be avoided when image filters are applied.

Definition at line 27 of file texture_contents.cc.

27 {
28 auto contents = std::make_shared<TextureContents>();
29 contents->destination_rect_ = destination;
30 return contents;
31 }

Referenced by impeller::PaintPassDelegate::CreateContentsForSubpassTarget(), impeller::Canvas::DrawImageRect(), impeller::Entity::FromSnapshot(), and impeller::testing::TEST_P().

## ◆ Render()

bool impeller::TextureContents::Render | ( | const ContentContext & | renderer,
|  | const Entity & | entity,
|  | RenderPass & | pass
| ) |  | const
| override virtual

Implements impeller::Contents.

Definition at line 107 of file texture_contents.cc.

109 {
110 auto capture = entity.GetCapture().CreateChild("TextureContents");
111
112 using VS = TextureFillVertexShader;
113 using FS = TextureFillFragmentShader;
114 using FSExternal = TextureFillExternalFragmentShader;
115
116 if (destination_rect_.IsEmpty() || source_rect_.IsEmpty() ||
117 texture_ == nullptr || texture_->GetSize().IsEmpty()) {
118 return true; // Nothing to render.
119 }
120
121 bool is_external_texture =
122 texture_->GetTextureDescriptor().type == TextureType::kTextureExternalOES;
123
124 // Expand the source rect by half a texel, which aligns sampled texels to the
125 // pixel grid if the source rect is the same size as the destination rect.
126 auto texture_coords =
127 Rect::MakeSize(texture_->GetSize())
128 .Project(capture.AddRect("Source rect", source_rect_).Expand(0.5));
129
130 VertexBufferBuilder<VS::PerVertexData> vertex_builder;
131
132 auto destination_rect =
133 capture.AddRect("Destination rect", destination_rect_);
134 vertex_builder.AddVertices({
135 {destination_rect.GetLeftTop(), texture_coords.GetLeftTop()},
136 {destination_rect.GetRightTop(), texture_coords.GetRightTop()},
137 {destination_rect.GetLeftBottom(), texture_coords.GetLeftBottom()},
138 {destination_rect.GetRightBottom(), texture_coords.GetRightBottom()},
139 });
140
141 auto& host_buffer = pass.GetTransientsBuffer();
142
143 VS::FrameInfo frame_info;
144 frame_info.mvp = pass.GetOrthographicTransform() *
145 capture.AddMatrix("Transform", entity.GetTransform());
146 frame_info.texture_sampler_y_coord_scale = texture_->GetYCoordScale();
147 frame_info.alpha = capture.AddScalar("Alpha", GetOpacity());
148
149 Command cmd;
150 if (label_.empty()) {
151 DEBUG_COMMAND_INFO(cmd, "Texture Fill");
152 } else {
153 DEBUG_COMMAND_INFO(cmd, "Texture Fill: " + label_);
154 }
155
156 auto pipeline_options = OptionsFromPassAndEntity(pass, entity);
157 if (!stencil_enabled_) {
158 pipeline_options.stencil_compare = CompareFunction::kAlways;
159 }
160 pipeline_options.primitive_type = PrimitiveType::kTriangleStrip;
161
162 #ifdef IMPELLER_ENABLE_OPENGLES
163 if (is_external_texture) {
164 cmd.pipeline = renderer.GetTextureExternalPipeline(pipeline_options);
165 } else {
166 cmd.pipeline = renderer.GetTexturePipeline(pipeline_options);
167 }
168 #else
169 cmd.pipeline = renderer.GetTexturePipeline(pipeline_options);
170 #endif // IMPELLER_ENABLE_OPENGLES
171
172 cmd.stencil_reference = entity.GetClipDepth();
173 cmd.BindVertices(vertex_builder.CreateVertexBuffer(host_buffer));
174 VS::BindFrameInfo(cmd, host_buffer.EmplaceUniform(frame_info));
175 if (is_external_texture) {
176 FSExternal::BindSAMPLEREXTERNALOESTextureSampler(
177 cmd, texture_,
178 renderer.GetContext()->GetSamplerLibrary()->GetSampler(
179 sampler_descriptor_));
180 } else {
181 FS::BindTextureSampler(
182 cmd, texture_,
183 renderer.GetContext()->GetSamplerLibrary()->GetSampler(
184 sampler_descriptor_));
185 }
186 pass.AddCommand(std::move(cmd));
187
188 return true;
189 }

References impeller::RenderPass::AddCommand(), impeller::VertexBufferBuilder< VertexType_, IndexType_ >::AddVertices(), impeller::Command::BindVertices(), impeller::Capture::CreateChild(), impeller::VertexBufferBuilder< VertexType_, IndexType_ >::CreateVertexBuffer(), DEBUG_COMMAND_INFO, impeller::Entity::GetCapture(), impeller::Entity::GetClipDepth(), impeller::ContentContext::GetContext(), GetOpacity(), impeller::RenderPass::GetOrthographicTransform(), impeller::ContentContext::GetTexturePipeline(), impeller::Entity::GetTransform(), impeller::RenderPass::GetTransientsBuffer(), impeller::TRect< T >::IsEmpty(), impeller::kAlways, impeller::kTextureExternalOES, impeller::kTriangleStrip, impeller::TRect< Scalar >::MakeSize(), impeller::OptionsFromPassAndEntity(), impeller::Command::pipeline, impeller::TRect< T >::Project(), and impeller::Command::stencil_reference.

## ◆ RenderToSnapshot()

std::optional< Snapshot > impeller::TextureContents::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 = `"Texture Snapshot"`
| ) |  | const
| override virtual

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)`.

Reimplemented from impeller::Contents.

Definition at line 76 of file texture_contents.cc.

82 {
83 // Passthrough textures that have simple rectangle paths and complete source
84 // rects.
85 auto bounds = destination_rect_;
86 auto opacity = GetOpacity();
87 if (source_rect_ == Rect::MakeSize(texture_->GetSize()) &&
88 (opacity >= 1 - kEhCloseEnough || defer_applying_opacity_)) {
89 auto scale = Vector2(bounds.GetSize() / Size(texture_->GetSize()));
90 return Snapshot{
91 .texture = texture_,
92 .transform = entity.GetTransform() *
93 Matrix::MakeTranslation(bounds.GetOrigin()) *
94 Matrix::MakeScale(scale),
95 .sampler_descriptor = sampler_descriptor.value_or(sampler_descriptor_),
96 .opacity = opacity};
97 }
98 return Contents::RenderToSnapshot(
99 renderer, // renderer
100 entity, // entity
101 std::nullopt, // coverage_limit
102 sampler_descriptor.value_or(sampler_descriptor_), // sampler_descriptor
103 true, // msaa_enabled
104 label); // label
105 }

References GetOpacity(), impeller::Entity::GetTransform(), impeller::kEhCloseEnough, impeller::Matrix::MakeScale(), impeller::TRect< Scalar >::MakeSize(), impeller::Matrix::MakeTranslation(), impeller::Contents::RenderToSnapshot(), and impeller::Snapshot::texture.

## ◆ SetDeferApplyingOpacity()

void impeller::TextureContents::SetDeferApplyingOpacity | ( | bool | defer_applying_opacity | ) |

Definition at line 207 of file texture_contents.cc.

207 {
208 defer_applying_opacity_ = defer_applying_opacity;
209 }

## ◆ SetDestinationRect()

void impeller::TextureContents::SetDestinationRect | ( | Rect | rect | ) |

Definition at line 37 of file texture_contents.cc.

37 {
38 destination_rect_ = rect;
39 }

## ◆ SetInheritedOpacity()

void impeller::TextureContents::SetInheritedOpacity | ( | Scalar | opacity | ) |
| override virtual

Inherit the provided opacity.

       Use of this method is invalid if CanAcceptOpacity returns false.

Reimplemented from impeller::Contents.

Definition at line 61 of file texture_contents.cc.

61 {
62 inherited_opacity_ = opacity;
63 }

## ◆ SetLabel()

void impeller::TextureContents::SetLabel | ( | std::string | label | ) |

Definition at line 33 of file texture_contents.cc.

33 {
34 label_ = std::move(label);
35 }

## ◆ SetOpacity()

void impeller::TextureContents::SetOpacity | ( | Scalar | opacity | ) |

Definition at line 49 of file texture_contents.cc.

49 {
50 opacity_ = opacity;
51 }

## ◆ SetSamplerDescriptor()

void impeller::TextureContents::SetSamplerDescriptor | ( | SamplerDescriptor | desc | ) |

Definition at line 199 of file texture_contents.cc.

199 {
200 sampler_descriptor_ = std::move(desc);
201 }

## ◆ SetSourceRect()

void impeller::TextureContents::SetSourceRect | ( | const Rect & | source_rect | ) |

Definition at line 191 of file texture_contents.cc.

191 {
192 source_rect_ = source_rect;
193 }

## ◆ SetStencilEnabled()

void impeller::TextureContents::SetStencilEnabled | ( | bool | enabled | ) |

Definition at line 53 of file texture_contents.cc.

53 {
54 stencil_enabled_ = enabled;
55 }

## ◆ SetTexture()

void impeller::TextureContents::SetTexture | ( | std::shared_ptr< Texture > | texture | ) |

Definition at line 41 of file texture_contents.cc.

41 {
42 texture_ = std::move(texture);
43 }

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

- impeller/entity/contents/texture_contents.h
- impeller/entity/contents/texture_contents.cc

impeller::TextureType::kTextureExternalOES
@ kTextureExternalOES
DEBUG_COMMAND_INFO
#define DEBUG_COMMAND_INFO(obj, arg)
Definition: command.h:28
impeller::kEhCloseEnough
constexpr float kEhCloseEnough
Definition: constants.h:56
impeller::TRect::TransformBounds
constexpr TRect TransformBounds(const Matrix &transform) const
Creates a new bounding box that contains this transformed rectangle.
Definition: rect.h:264
impeller::Vector2
Point Vector2
Definition: point.h:312
impeller::Size
TSize< Scalar > Size
Definition: size.h:137
impeller::Matrix::MakeTranslation
static constexpr Matrix MakeTranslation(const Vector3 &t)
Definition: matrix.h:95
impeller::TextureContents::GetOpacity
Scalar GetOpacity() const
Definition: texture_contents.cc:65
impeller::TRect::IsEmpty
constexpr bool IsEmpty() const
Returns true if either of the width or height are 0, negative, or NaN.
Definition: rect.h:138
impeller::OptionsFromPassAndEntity
ContentContextOptions OptionsFromPassAndEntity(const RenderPass &pass, const Entity &entity)
Definition: contents.cc:28
impeller::PrimitiveType::kTriangleStrip
@ kTriangleStrip
impeller::CompareFunction::kAlways
@ kAlways
Comparison test passes always passes.
impeller::TRect< Scalar >::MakeSize
constexpr static TRect MakeSize(const TSize< U > &size)
Definition: rect.h:44
impeller::TRect::Project
constexpr TRect< T > Project(TRect< T > source) const
Returns a new rectangle that represents the projection of the source rectangle onto this rectangle....
Definition: rect.h:424
impeller::Matrix::MakeScale
static constexpr Matrix MakeScale(const Vector3 &s)
Definition: matrix.h:104
impeller::Contents::RenderToSnapshot
virtual 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="Snapshot") const
Render this contents to a snapshot, respecting the entity's transform, path, clip depth,...
Definition: contents.cc:57