impeller::FramebufferBlendContents Class Reference

#include <framebuffer_blend_contents.h>

Inheritance diagram for impeller::FramebufferBlendContents:

Public Member Functions
	FramebufferBlendContents ()
	~FramebufferBlendContents () override
void	SetBlendMode (BlendMode blend_mode)
void	SetChildContents (std::shared_ptr< Contents > child_contents)
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.
const std::shared_ptr< Geometry > &	GetGeometry () const
	Get the geometry that this contents will use to render.
void	SetEffectTransform (Matrix matrix)
	Set the effect transform for this color source.
const Matrix &	GetInverseEffectTransform () const
	Set the inverted effect transform for this color source.
void	SetOpacityFactor (Scalar opacity)
	Set the opacity factor for this color source.
Scalar	GetOpacityFactor () const
	Get the opacity factor for this color source.
virtual bool	IsSolidColor () const
bool	CanInheritOpacity (const Entity &entity) const override
	Whether or not this contents can accept the opacity peephole optimization.
void	SetInheritedOpacity (Scalar opacity) override
	Inherit the provided 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.
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().
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.
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.
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, and blend mode. The result texture size is always the size of GetCoverage(entity).
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.
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.
virtual const FilterContents *	AsFilter () const
	Cast to a filter. Returns nullptr if this Contents is not a filter.
virtual bool	ApplyColorFilter (const ColorFilterProc &color_filter_proc)
	If possible, applies a color filter to this contents inputs on the CPU.

Private Member Functions
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.
bool	Render (const ContentContext &renderer, const Entity &entity, RenderPass &pass) const override

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)
Protected Types inherited from impeller::ColorSourceContents
using	BindFragmentCallback = std::function< bool(RenderPass &pass)>
using	PipelineBuilderMethod = std::shared_ptr< Pipeline< PipelineDescriptor > >(impeller::ContentContext::*)(ContentContextOptions) const
using	PipelineBuilderCallback = std::function< std::shared_ptr< Pipeline< PipelineDescriptor > >(ContentContextOptions)>
Protected Member Functions inherited from impeller::ColorSourceContents
template<typename VertexShaderT >
bool	DrawGeometry (const ContentContext &renderer, const Entity &entity, RenderPass &pass, const PipelineBuilderCallback &pipeline_callback, typename VertexShaderT::FrameInfo frame_info, const BindFragmentCallback &bind_fragment_callback) const

Detailed Description

Definition at line 33 of file framebuffer_blend_contents.h.

Constructor & Destructor Documentation

FramebufferBlendContents()

impeller::FramebufferBlendContents::FramebufferBlendContents ( )

default

~FramebufferBlendContents()

impeller::FramebufferBlendContents::~FramebufferBlendContents ( )

overridedefault

Member Function Documentation

GetCoverage()

std::optional< Rect > impeller::FramebufferBlendContents::GetCoverage ( const Entity &  entity ) const

overrideprivatevirtual

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.

Reimplemented from impeller::ColorSourceContents.

Definition at line 26 of file framebuffer_blend_contents.cc.

                                {
  return child_contents_->GetCoverage(entity);
}

Render()

bool impeller::FramebufferBlendContents::Render ( const ContentContext &  renderer, const Entity &  entity, RenderPass &  pass  ) const

overrideprivatevirtual

Implements impeller::Contents.

Definition at line 31 of file framebuffer_blend_contents.cc.

                                                              {
  if (!renderer.GetDeviceCapabilities().SupportsFramebufferFetch()) {
    return false;
  }
 
  using VS = FramebufferBlendScreenPipeline::VertexShader;
  using FS = FramebufferBlendScreenPipeline::FragmentShader;
 
  auto& host_buffer = renderer.GetTransientsBuffer();
 
  auto src_snapshot = child_contents_->RenderToSnapshot(
      renderer,                                    // renderer
      entity,                                      // entity
      Rect::MakeSize(pass.GetRenderTargetSize()),  // coverage_limit
      std::nullopt,                                // sampler_descriptor
      true,                                        // msaa_enabled
      /*mip_count=*/1,
      "FramebufferBlendContents Snapshot");  // label
 
  if (!src_snapshot.has_value()) {
    return true;
  }
  auto coverage = src_snapshot->GetCoverage();
  if (!coverage.has_value()) {
    return true;
  }
  Rect src_coverage = coverage.value();
 
  auto size = src_coverage.GetSize();
  VertexBufferBuilder<VS::PerVertexData> vtx_builder;
  vtx_builder.AddVertices({
      {Point(0, 0), Point(0, 0)},
      {Point(size.width, 0), Point(1, 0)},
      {Point(0, size.height), Point(0, 1)},
      {Point(size.width, size.height), Point(1, 1)},
  });
 
  auto options = OptionsFromPass(pass);
  options.blend_mode = BlendMode::kSource;
  options.primitive_type = PrimitiveType::kTriangleStrip;
 
  pass.SetCommandLabel("Framebuffer Advanced Blend Filter");
  pass.SetVertexBuffer(vtx_builder.CreateVertexBuffer(host_buffer));
 
  switch (blend_mode_) {
    case BlendMode::kScreen:
      pass.SetPipeline(renderer.GetFramebufferBlendScreenPipeline(options));
      break;
    case BlendMode::kOverlay:
      pass.SetPipeline(renderer.GetFramebufferBlendOverlayPipeline(options));
      break;
    case BlendMode::kDarken:
      pass.SetPipeline(renderer.GetFramebufferBlendDarkenPipeline(options));
      break;
    case BlendMode::kLighten:
      pass.SetPipeline(renderer.GetFramebufferBlendLightenPipeline(options));
      break;
    case BlendMode::kColorDodge:
      pass.SetPipeline(renderer.GetFramebufferBlendColorDodgePipeline(options));
      break;
    case BlendMode::kColorBurn:
      pass.SetPipeline(renderer.GetFramebufferBlendColorBurnPipeline(options));
      break;
    case BlendMode::kHardLight:
      pass.SetPipeline(renderer.GetFramebufferBlendHardLightPipeline(options));
      break;
    case BlendMode::kSoftLight:
      pass.SetPipeline(renderer.GetFramebufferBlendSoftLightPipeline(options));
      break;
    case BlendMode::kDifference:
      pass.SetPipeline(renderer.GetFramebufferBlendDifferencePipeline(options));
      break;
    case BlendMode::kExclusion:
      pass.SetPipeline(renderer.GetFramebufferBlendExclusionPipeline(options));
      break;
    case BlendMode::kMultiply:
      pass.SetPipeline(renderer.GetFramebufferBlendMultiplyPipeline(options));
      break;
    case BlendMode::kHue:
      pass.SetPipeline(renderer.GetFramebufferBlendHuePipeline(options));
      break;
    case BlendMode::kSaturation:
      pass.SetPipeline(renderer.GetFramebufferBlendSaturationPipeline(options));
      break;
    case BlendMode::kColor:
      pass.SetPipeline(renderer.GetFramebufferBlendColorPipeline(options));
      break;
    case BlendMode::kLuminosity:
      pass.SetPipeline(renderer.GetFramebufferBlendLuminosityPipeline(options));
      break;
    default:
      return false;
  }
 
  VS::FrameInfo frame_info;
  FS::FragInfo frag_info;
 
  auto src_sampler_descriptor = src_snapshot->sampler_descriptor;
  if (renderer.GetDeviceCapabilities().SupportsDecalSamplerAddressMode()) {
    src_sampler_descriptor.width_address_mode = SamplerAddressMode::kDecal;
    src_sampler_descriptor.height_address_mode = SamplerAddressMode::kDecal;
  }
  const std::unique_ptr<const Sampler>& src_sampler =
      renderer.GetContext()->GetSamplerLibrary()->GetSampler(
          src_sampler_descriptor);
  FS::BindTextureSamplerSrc(pass, src_snapshot->texture, src_sampler);
 
  frame_info.mvp = Entity::GetShaderTransform(entity.GetShaderClipDepth(), pass,
                                              src_snapshot->transform);
  frame_info.src_y_coord_scale = src_snapshot->texture->GetYCoordScale();
  VS::BindFrameInfo(pass, host_buffer.EmplaceUniform(frame_info));
 
  frag_info.src_input_alpha = src_snapshot->opacity;
  FS::BindFragInfo(pass, host_buffer.EmplaceUniform(frag_info));
 
  return pass.Draw().ok();
}

SetBlendMode()

void impeller::FramebufferBlendContents::SetBlendMode

(

BlendMode

blend_mode

)

Definition at line 16 of file framebuffer_blend_contents.cc.

                                                                {
  blend_mode_ = blend_mode;
}

SetChildContents()

void impeller::FramebufferBlendContents::SetChildContents

(

std::shared_ptr< Contents >

child_contents

)

Definition at line 20 of file framebuffer_blend_contents.cc.

                                            {
  child_contents_ = std::move(child_contents);
}

---

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

• impeller/entity/contents/framebuffer_blend_contents.h
• impeller/entity/contents/framebuffer_blend_contents.cc