Flutter Impeller
impeller::AtlasColorContents Class Referencefinal

#include <atlas_contents.h>

Inheritance diagram for impeller::AtlasColorContents:
impeller::Contents

Public Member Functions

 AtlasColorContents (const AtlasContents &parent)
 
 ~AtlasColorContents () override
 
std::optional< RectGetCoverage (const Entity &entity) const override
 Get the screen space bounding rectangle that this contents affects. More...
 
bool Render (const ContentContext &renderer, const Entity &entity, RenderPass &pass) const override
 
void SetAlpha (Scalar alpha)
 
void SetCoverage (Rect coverage)
 
void SetSubAtlas (const std::shared_ptr< SubAtlasResult > &subatlas)
 
- 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 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 std::optional< SnapshotRenderToSnapshot (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, stencil 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 > &stencil_coverage) const
 
std::optional< SizeGetColorSourceSize () 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< ColorAsBackgroundColor (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 FilterContentsAsFilter () 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< ContentsMakeAnonymous (RenderProc render_proc, CoverageProc coverage_proc)
 

Detailed Description

Definition at line 128 of file atlas_contents.h.

Constructor & Destructor Documentation

◆ AtlasColorContents()

impeller::AtlasColorContents::AtlasColorContents ( const AtlasContents parent)
explicit

Definition at line 440 of file atlas_contents.cc.

441  : parent_(parent) {}

◆ ~AtlasColorContents()

impeller::AtlasColorContents::~AtlasColorContents ( )
override

Definition at line 443 of file atlas_contents.cc.

443 {}

Member Function Documentation

◆ GetCoverage()

std::optional< Rect > impeller::AtlasColorContents::GetCoverage ( const Entity entity) const
overridevirtual

Get the screen space bounding rectangle that this contents affects.

Implements impeller::Contents.

Definition at line 445 of file atlas_contents.cc.

446  {
447  return coverage_.TransformBounds(entity.GetTransformation());
448 }

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

◆ Render()

bool impeller::AtlasColorContents::Render ( const ContentContext renderer,
const Entity entity,
RenderPass pass 
) const
overridevirtual

Implements impeller::Contents.

Definition at line 463 of file atlas_contents.cc.

465  {
468 
469  std::vector<Rect> texture_coords;
470  std::vector<Matrix> transforms;
471  std::vector<Color> colors;
472  if (subatlas_) {
473  texture_coords = subatlas_->sub_texture_coords;
474  colors = subatlas_->sub_colors;
475  transforms = subatlas_->sub_transforms;
476  } else {
477  texture_coords = parent_.GetTextureCoordinates();
478  transforms = parent_.GetTransforms();
479  colors = parent_.GetColors();
480  }
481 
482  VertexBufferBuilder<VS::PerVertexData> vertex_builder;
483  vertex_builder.Reserve(texture_coords.size() * 6);
484  constexpr size_t indices[6] = {0, 1, 2, 1, 2, 3};
485  for (size_t i = 0; i < texture_coords.size(); i++) {
486  auto sample_rect = texture_coords[i];
487  auto matrix = transforms[i];
488  auto transformed_points =
489  Rect::MakeSize(sample_rect.size).GetTransformedPoints(matrix);
490 
491  for (size_t j = 0; j < 6; j++) {
492  VS::PerVertexData data;
493  data.position = transformed_points[indices[j]];
494  data.color = colors[i].Premultiply();
495  vertex_builder.AppendVertex(data);
496  }
497  }
498 
499  if (!vertex_builder.HasVertices()) {
500  return true;
501  }
502 
503  Command cmd;
504  DEBUG_COMMAND_INFO(cmd, "AtlasColors");
505 
506  auto& host_buffer = pass.GetTransientsBuffer();
507 
508  VS::FrameInfo frame_info;
509  frame_info.mvp = Matrix::MakeOrthographic(pass.GetRenderTargetSize()) *
510  entity.GetTransformation();
511 
512  FS::FragInfo frag_info;
513  frag_info.alpha = alpha_;
514 
515  auto opts = OptionsFromPassAndEntity(pass, entity);
516  opts.blend_mode = BlendMode::kSourceOver;
517  cmd.pipeline = renderer.GetGeometryColorPipeline(opts);
518  cmd.stencil_reference = entity.GetStencilDepth();
519  cmd.BindVertices(vertex_builder.CreateVertexBuffer(host_buffer));
520  VS::BindFrameInfo(cmd, host_buffer.EmplaceUniform(frame_info));
521  FS::BindFragInfo(cmd, host_buffer.EmplaceUniform(frag_info));
522  return pass.AddCommand(std::move(cmd));
523 }

References impeller::RenderPass::AddCommand(), impeller::VertexBufferBuilder< VertexType_, IndexType_ >::AppendVertex(), impeller::Command::BindVertices(), impeller::VertexBufferBuilder< VertexType_, IndexType_ >::CreateVertexBuffer(), DEBUG_COMMAND_INFO, impeller::AtlasContents::GetColors(), impeller::ContentContext::GetGeometryColorPipeline(), impeller::RenderPass::GetRenderTargetSize(), impeller::Entity::GetStencilDepth(), impeller::AtlasContents::GetTextureCoordinates(), impeller::Entity::GetTransformation(), impeller::TRect< T >::GetTransformedPoints(), impeller::AtlasContents::GetTransforms(), impeller::RenderPass::GetTransientsBuffer(), impeller::VertexBufferBuilder< VertexType_, IndexType_ >::HasVertices(), impeller::kSourceOver, impeller::Matrix::MakeOrthographic(), impeller::TRect< Scalar >::MakeSize(), impeller::OptionsFromPassAndEntity(), impeller::Command::pipeline, impeller::VertexBufferBuilder< VertexType_, IndexType_ >::Reserve(), and impeller::Command::stencil_reference.

◆ SetAlpha()

void impeller::AtlasColorContents::SetAlpha ( Scalar  alpha)

Definition at line 450 of file atlas_contents.cc.

450  {
451  alpha_ = alpha;
452 }

◆ SetCoverage()

void impeller::AtlasColorContents::SetCoverage ( Rect  coverage)

Definition at line 454 of file atlas_contents.cc.

454  {
455  coverage_ = coverage;
456 }

◆ SetSubAtlas()

void impeller::AtlasColorContents::SetSubAtlas ( const std::shared_ptr< SubAtlasResult > &  subatlas)

Definition at line 458 of file atlas_contents.cc.

459  {
460  subatlas_ = subatlas;
461 }

The documentation for this class was generated from the following files:
DEBUG_COMMAND_INFO
#define DEBUG_COMMAND_INFO(obj, arg)
Definition: command.h:31
impeller::TRect::TransformBounds
constexpr TRect TransformBounds(const Matrix &transform) const
Creates a new bounding box that contains this transformed rectangle.
Definition: rect.h:204
impeller::RenderPipelineT::FragmentShader
FragmentShader_ FragmentShader
Definition: pipeline.h:91
impeller::OptionsFromPassAndEntity
ContentContextOptions OptionsFromPassAndEntity(const RenderPass &pass, const Entity &entity)
Definition: contents.cc:30
impeller::BlendMode::kSourceOver
@ kSourceOver
impeller::TRect::GetTransformedPoints
constexpr std::array< TPoint< T >, 4 > GetTransformedPoints(const Matrix &transform) const
Definition: rect.h:193
impeller::AtlasContents::GetTransforms
const std::vector< Matrix > & GetTransforms() const
Definition: atlas_contents.cc:178
impeller::AtlasContents::GetTextureCoordinates
const std::vector< Rect > & GetTextureCoordinates() const
Definition: atlas_contents.cc:182
impeller::TRect< Scalar >::MakeSize
constexpr static TRect MakeSize(const TSize< U > &size)
Definition: rect.h:52
impeller::Matrix::MakeOrthographic
static constexpr Matrix MakeOrthographic(TSize< T > size)
Definition: matrix.h:448
impeller::RenderPipelineT::VertexShader
VertexShader_ VertexShader
Definition: pipeline.h:90
impeller::AtlasContents::GetColors
const std::vector< Color > & GetColors() const
Definition: atlas_contents.cc:186