| 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 | SetStrictSourceRect (bool strict)
bool | GetStrictSourceRect () 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, int32_t mip_count=1, 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 17 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 210 of file texture_contents.cc.

210 {
211 return sampler_descriptor_;
212 }

## ◆ GetSourceRect()

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

Definition at line 194 of file texture_contents.cc.

194 {
195 return source_rect_;
196 }

## ◆ GetStrictSourceRect()

bool impeller::TextureContents::GetStrictSourceRect | ( |  | ) | const

Definition at line 202 of file texture_contents.cc.

202 {
203 return strict_source_rect_enabled_;
204 }

## ◆ 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::Entity::FromSnapshot(), impeller::EntityPass::Render(), impeller::ExperimentalCanvas::SaveLayer(), 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 109 of file texture_contents.cc.

111 {
112 using VS = TextureFillVertexShader;
113 using FS = TextureFillFragmentShader;
114 using FSStrict = TextureFillStrictSrcFragmentShader;
115
116 if (destination_rect_.IsEmpty() || source_rect_.IsEmpty() ||
117 texture_ == nullptr || texture_->GetSize().IsEmpty()) {
118 return true; // Nothing to render.
119 }
120
121 [[maybe_unused]] bool is_external_texture =
122 texture_->GetTextureDescriptor().type == TextureType::kTextureExternalOES;
123 FML_DCHECK(!is_external_texture);
124
125 auto texture_coords =
126 Rect::MakeSize(texture_->GetSize()).Project(source_rect_);
127
128 VertexBufferBuilder<VS::PerVertexData> vertex_builder;
129 vertex_builder.AddVertices({
130 {destination_rect_.GetLeftTop(), texture_coords.GetLeftTop()},
131 {destination_rect_.GetRightTop(), texture_coords.GetRightTop()},
132 {destination_rect_.GetLeftBottom(), texture_coords.GetLeftBottom()},
133 {destination_rect_.GetRightBottom(), texture_coords.GetRightBottom()},
134 });
135
136 auto& host_buffer = renderer.GetTransientsBuffer();
137
138 VS::FrameInfo frame_info;
139 frame_info.mvp = entity.GetShaderTransform(pass);
140 frame_info.texture_sampler_y_coord_scale = texture_->GetYCoordScale();
141
142 #ifdef IMPELLER_DEBUG
143 if (label_.empty()) {
144 pass.SetCommandLabel("Texture Fill");
145 } else {
146 pass.SetCommandLabel("Texture Fill: " + label_);
147 }
148 #endif // IMPELLER_DEBUG
149
150 auto pipeline_options = OptionsFromPassAndEntity(pass, entity);
151 if (!stencil_enabled_) {
152 pipeline_options.stencil_mode = ContentContextOptions::StencilMode::kIgnore;
153 }
154 pipeline_options.primitive_type = PrimitiveType::kTriangleStrip;
155
156 pass.SetPipeline(strict_source_rect_enabled_
157 ? renderer.GetTextureStrictSrcPipeline(pipeline_options)
158 : renderer.GetTexturePipeline(pipeline_options));
159
160 pass.SetVertexBuffer(vertex_builder.CreateVertexBuffer(host_buffer));
161 VS::BindFrameInfo(pass, host_buffer.EmplaceUniform(frame_info));
162
163 if (strict_source_rect_enabled_) {
164 // For a strict source rect, shrink the texture coordinate range by half a
165 // texel to ensure that linear filtering does not sample anything outside
166 // the source rect bounds.
167 auto strict_texture_coords =
168 Rect::MakeSize(texture_->GetSize()).Project(source_rect_.Expand(-0.5));
169
170 FSStrict::FragInfo frag_info;
171 frag_info.source_rect = Vector4(strict_texture_coords.GetLTRB());
172 frag_info.alpha = GetOpacity();
173 FSStrict::BindFragInfo(pass, host_buffer.EmplaceUniform((frag_info)));
174 FSStrict::BindTextureSampler(
175 pass, texture_,
176 renderer.GetContext()->GetSamplerLibrary()->GetSampler(
177 sampler_descriptor_));
178 } else {
179 FS::FragInfo frag_info;
180 frag_info.alpha = GetOpacity();
181 FS::BindFragInfo(pass, host_buffer.EmplaceUniform((frag_info)));
182 FS::BindTextureSampler(
183 pass, texture_,
184 renderer.GetContext()->GetSamplerLibrary()->GetSampler(
185 sampler_descriptor_));
186 }
187 return pass.Draw().ok();
188 }

References impeller::VertexBufferBuilder< VertexType_, IndexType_ >::AddVertices(), impeller::VertexBufferBuilder< VertexType_, IndexType_ >::CreateVertexBuffer(), impeller::RenderPass::Draw(), impeller::TRect< T >::Expand(), impeller::ContentContext::GetContext(), impeller::TRect< T >::GetLeftBottom(), impeller::TRect< T >::GetLeftTop(), GetOpacity(), impeller::TRect< T >::GetRightBottom(), impeller::TRect< T >::GetRightTop(), impeller::Entity::GetShaderTransform(), impeller::ContentContext::GetTexturePipeline(), impeller::ContentContext::GetTextureStrictSrcPipeline(), impeller::ContentContext::GetTransientsBuffer(), impeller::TRect< T >::IsEmpty(), impeller::ContentContextOptions::kIgnore, impeller::kTextureExternalOES, impeller::kTriangleStrip, impeller::TRect< Scalar >::MakeSize(), impeller::OptionsFromPassAndEntity(), impeller::TRect< T >::Project(), impeller::RenderPass::SetCommandLabel(), impeller::RenderPass::SetPipeline(), and impeller::RenderPass::SetVertexBuffer().

## ◆ 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`,
|  | int32_t | mip_count = `1`,
|  | 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.

83 {
84 // Passthrough textures that have simple rectangle paths and complete source
85 // rects.
86 auto bounds = destination_rect_;
87 auto opacity = GetOpacity();
88 if (source_rect_ == Rect::MakeSize(texture_->GetSize()) &&
89 (opacity >= 1 - kEhCloseEnough || defer_applying_opacity_)) {
90 auto scale = Vector2(bounds.GetSize() / Size(texture_->GetSize()));
91 return Snapshot{
92 .texture = texture_,
93 .transform = entity.GetTransform() *
94 Matrix::MakeTranslation(bounds.GetOrigin()) *
95 Matrix::MakeScale(scale),
96 .sampler_descriptor = sampler_descriptor.value_or(sampler_descriptor_),
97 .opacity = opacity};
98 }
99 return Contents::RenderToSnapshot(
100 renderer, // renderer
101 entity, // entity
102 std::nullopt, // coverage_limit
103 sampler_descriptor.value_or(sampler_descriptor_), // sampler_descriptor
104 true, // msaa_enabled
105 /*mip_count=*/mip_count,
106 label); // label
107 }

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

## ◆ SetDeferApplyingOpacity()

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

Definition at line 214 of file texture_contents.cc.

214 {
215 defer_applying_opacity_ = defer_applying_opacity;
216 }

## ◆ 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 206 of file texture_contents.cc.

206 {
207 sampler_descriptor_ = std::move(desc);
208 }

## ◆ SetSourceRect()

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

Definition at line 190 of file texture_contents.cc.

190 {
191 source_rect_ = source_rect;
192 }

## ◆ SetStencilEnabled()

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

Definition at line 53 of file texture_contents.cc.

53 {
54 stencil_enabled_ = enabled;
55 }

## ◆ SetStrictSourceRect()

void impeller::TextureContents::SetStrictSourceRect | ( | bool | strict | ) |

Definition at line 198 of file texture_contents.cc.

198 {
199 strict_source_rect_enabled_ = strict;
200 }

## ◆ 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::ContentContextOptions::StencilMode::kIgnore
@ kIgnore
impeller::TextureType::kTextureExternalOES
@ kTextureExternalOES
impeller::kEhCloseEnough
constexpr float kEhCloseEnough
Definition: constants.h:56
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, int32_t mip_count=1, const std::string &label="Snapshot") const
Render this contents to a snapshot, respecting the entity's transform, path, clip depth,...
Definition: contents.cc:63
impeller::TRect::TransformBounds
constexpr TRect TransformBounds(const Matrix &transform) const
Creates a new bounding box that contains this transformed rectangle.
Definition: rect.h:463
impeller::TRect::GetLeftTop
constexpr TPoint< T > GetLeftTop() const
Definition: rect.h:349
impeller::Vector2
Point Vector2
Definition: point.h:326
impeller::Size
TSize< Scalar > Size
Definition: size.h:137
impeller::Matrix::MakeTranslation
static constexpr Matrix MakeTranslation(const Vector3 &t)
Definition: matrix.h:95
impeller::TRect::GetRightTop
constexpr TPoint< T > GetRightTop() const
Definition: rect.h:353
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:287
impeller::VS
SolidFillVertexShader VS
Definition: stroke_path_geometry.cc:16
impeller::OptionsFromPassAndEntity
ContentContextOptions OptionsFromPassAndEntity(const RenderPass &pass, const Entity &entity)
Definition: contents.cc:34
impeller::PrimitiveType::kTriangleStrip
@ kTriangleStrip
impeller::TRect::GetLeftBottom
constexpr TPoint< T > GetLeftBottom() const
Definition: rect.h:357
impeller::TRect< Scalar >::MakeSize
constexpr static TRect MakeSize(const TSize< U > &size)
Definition: rect.h:146
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:656
scale
const Scalar scale
Definition: stroke_path_geometry.cc:308
impeller::TRect::GetRightBottom
constexpr TPoint< T > GetRightBottom() const
Definition: rect.h:361
impeller::Matrix::MakeScale
static constexpr Matrix MakeScale(const Vector3 &s)
Definition: matrix.h:104
impeller::TRect::Expand
constexpr TRect< T > Expand(T left, T top, T right, T bottom) const
Returns a rectangle with expanded edges. Negative expansion results in shrinking.
Definition: rect.h:605