| Flutter Impeller |

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

`#include <scene_contents.h>`

Inheritance diagram for impeller::SceneContents:

## Public Member Functions
| SceneContents ()
| ~SceneContents () override
void | SetCameraTransform (Matrix matrix)
void | SetNode (std::shared_ptr< scene::Node > node)
bool | Render (const ContentContext &renderer, const Entity &entity, RenderPass &pass) const override
Public Member Functions inherited from impeller::ColorSourceContents
| ColorSourceContents ()
| ~ColorSourceContents () override
void | SetGeometry (std::shared_ptr< Geometry > geometry)
| Set the geometry that this contents will use to render. More...
const std::shared_ptr< Geometry > & | GetGeometry () const
| Get the geometry that this contents will use to render. More...
void | SetEffectTransform (Matrix matrix)
| Set the effect transform for this color source. More...
const Matrix & | GetInverseEffectTransform () const
| Set the inverted effect transform for this color source. More...
void | SetOpacityFactor (Scalar opacity)
| Set the opacity factor for this color source. More...
Scalar | GetOpacityFactor () const
| Get the opacity factor for this color source. More...
virtual bool | IsSolidColor () const
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...
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...
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 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, and blend mode. The result texture size is always the size of `GetCoverage(entity)`. 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...

## 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)>
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 22 of file scene_contents.h.

## Constructor & Destructor Documentation

## ◆ SceneContents()

impeller::SceneContents::SceneContents | ( |  | ) |
| default

## ◆ ~SceneContents()

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

## Member Function Documentation

## ◆ Render()

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

Implements impeller::Contents.

Definition at line 29 of file scene_contents.cc.

31 {
32 if (!node_) {
33 return true;
34 }
35
36 auto coverage = GetCoverage(entity);
37 if (!coverage.has_value()) {
38 return true;
39 }
40
41 // This happens for CoverGeometry (DrawPaint). In this situation,
42 // Draw the scene to the full layer.
43 if (coverage.value().IsMaximum()) {
44 coverage = Rect::MakeSize(pass.GetRenderTargetSize());
45 }
46
47 RenderTarget subpass_target;
48 if (renderer.GetContext()->GetCapabilities()->SupportsOffscreenMSAA()) {
49 subpass_target = RenderTarget::CreateOffscreenMSAA(
50 *renderer.GetContext(), // context
51 *renderer.GetRenderTargetCache(), // allocator
52 ISize(coverage.value().GetSize()), // size
53 "SceneContents", // label
54 RenderTarget::AttachmentConfigMSAA{
55 .storage_mode = StorageMode::kDeviceTransient,
56 .resolve_storage_mode = StorageMode::kDevicePrivate,
57 .load_action = LoadAction::kClear,
58 .store_action = StoreAction::kMultisampleResolve,
59 }, // color_attachment_config
60 RenderTarget::AttachmentConfig{
61 .storage_mode = StorageMode::kDeviceTransient,
62 .load_action = LoadAction::kDontCare,
63 .store_action = StoreAction::kDontCare,
64 } // stencil_attachment_config
65 );
66 } else {
67 subpass_target = RenderTarget::CreateOffscreen(
68 *renderer.GetContext(), // context
69 *renderer.GetRenderTargetCache(), // allocator
70 ISize(coverage.value().GetSize()), // size
71 "SceneContents", // label
72 RenderTarget::AttachmentConfig{
73 .storage_mode = StorageMode::kDevicePrivate,
74 .load_action = LoadAction::kClear,
75 .store_action = StoreAction::kStore,
76 }, // color_attachment_config
77 RenderTarget::AttachmentConfig{
78 .storage_mode = StorageMode::kDeviceTransient,
79 .load_action = LoadAction::kClear,
80 .store_action = StoreAction::kDontCare,
81 } // stencil_attachment_config
82 );
83 }
84
85 if (!subpass_target.IsValid()) {
86 return false;
87 }
88
89 scene::Scene scene(renderer.GetSceneContext());
90 scene.GetRoot().AddChild(node_);
91
92 if (!scene.Render(subpass_target, camera_transform_)) {
93 return false;
94 }
95
96 // Render the texture to the pass.
97 TiledTextureContents contents;
98 contents.SetGeometry(GetGeometry());
99 contents.SetTexture(subpass_target.GetRenderTargetTexture());
100 contents.SetEffectTransform(
101 Matrix::MakeScale(1 / entity.GetTransform().GetScale()));
102 return contents.Render(renderer, entity, pass);
103 }

References impeller::scene::Node::AddChild(), impeller::RenderTarget::CreateOffscreen(), impeller::RenderTarget::CreateOffscreenMSAA(), impeller::ContentContext::GetContext(), impeller::ColorSourceContents::GetCoverage(), impeller::ColorSourceContents::GetGeometry(), impeller::ContentContext::GetRenderTargetCache(), impeller::RenderPass::GetRenderTargetSize(), impeller::RenderTarget::GetRenderTargetTexture(), impeller::scene::Scene::GetRoot(), impeller::Matrix::GetScale(), impeller::Entity::GetTransform(), impeller::RenderTarget::IsValid(), impeller::Matrix::MakeScale(), impeller::TRect< Scalar >::MakeSize(), impeller::scene::Scene::Render(), impeller::TiledTextureContents::Render(), impeller::ColorSourceContents::SetEffectTransform(), impeller::ColorSourceContents::SetGeometry(), and impeller::TiledTextureContents::SetTexture().

## ◆ SetCameraTransform()

void impeller::SceneContents::SetCameraTransform | ( | Matrix | matrix | ) |

Definition at line 21 of file scene_contents.cc.

21 {
22 camera_transform_ = matrix;
23 }

## ◆ SetNode()

void impeller::SceneContents::SetNode | ( | std::shared_ptr< scene::Node > | node | ) |

Definition at line 25 of file scene_contents.cc.

25 {
26 node_ = std::move(node);
27 }

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

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

impeller::ColorSourceContents::GetGeometry
const std::shared_ptr< Geometry > & GetGeometry() const
Get the geometry that this contents will use to render.
Definition: color_source_contents.cc:21
impeller::ISize
TSize< int64_t > ISize
Definition: size.h:138
impeller::RenderTarget::CreateOffscreen
static RenderTarget CreateOffscreen(const Context &context, RenderTargetAllocator &allocator, ISize size, const std::string &label="Offscreen", AttachmentConfig color_attachment_config=kDefaultColorAttachmentConfig, std::optional< AttachmentConfig > stencil_attachment_config=kDefaultStencilAttachmentConfig)
Definition: render_target.cc:223
impeller::ColorSourceContents::GetCoverage
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.
Definition: color_source_contents.cc:45
impeller::TRect< Scalar >::MakeSize
constexpr static TRect MakeSize(const TSize< U > &size)
Definition: rect.h:44
impeller::Matrix::MakeScale
static constexpr Matrix MakeScale(const Vector3 &s)
Definition: matrix.h:104
impeller::RenderTarget::CreateOffscreenMSAA
static RenderTarget CreateOffscreenMSAA(const Context &context, RenderTargetAllocator &allocator, ISize size, const std::string &label="Offscreen MSAA", AttachmentConfigMSAA color_attachment_config=kDefaultColorAttachmentConfigMSAA, std::optional< AttachmentConfig > stencil_attachment_config=kDefaultStencilAttachmentConfig)
Definition: render_target.cc:265