impeller::RuntimeEffectContents Class Reference

#include <runtime_effect_contents.h>

Inheritance diagram for impeller::RuntimeEffectContents:

Classes
struct	TextureInput

Public Member Functions
void	SetRuntimeStage (std::shared_ptr< RuntimeStage > runtime_stage)
void	SetUniformData (std::shared_ptr< std::vector< uint8_t >> uniform_data)
void	SetTextureInputs (std::vector< TextureInput > texture_inputs)
bool	CanInheritOpacity (const Entity &entity) const override
	Whether or not this contents can accept the opacity peephole optimization. More...
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...
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 17 of file runtime_effect_contents.h.

Member Function Documentation

CanInheritOpacity()

bool impeller::RuntimeEffectContents::CanInheritOpacity ( const Entity &  entity ) const

overridevirtual

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::ColorSourceContents.

Definition at line 40 of file runtime_effect_contents.cc.

                                                                        {
  return false;
}

Render()

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

overridevirtual

Get or register shader.

Resolve geometry.

Get or create runtime stage pipeline.

Vertex stage uniforms.

Fragment stage uniforms.

Implements impeller::Contents.

Definition at line 79 of file runtime_effect_contents.cc.

                                                           {
  // TODO(jonahwilliams): FragmentProgram API is not fully wired up on Android.
  // Disable until this is complete so that integration tests and benchmarks can
  // run m3 applications.
  if (renderer.GetContext()->GetBackendType() ==
      Context::BackendType::kVulkan) {
    FML_DLOG(WARNING)
        << "Fragment programs not supported on Vulkan. Content dropped.";
    return true;
  }
  auto context = renderer.GetContext();
  auto library = context->GetShaderLibrary();
 
  //--------------------------------------------------------------------------
  /// Get or register shader.
  ///
 
  // TODO(113719): Register the shader function earlier.
 
  std::shared_ptr<const ShaderFunction> function = library->GetFunction(
      runtime_stage_->GetEntrypoint(), ShaderStage::kFragment);
 
  if (function && runtime_stage_->IsDirty()) {
    context->GetPipelineLibrary()->RemovePipelinesWithEntryPoint(function);
    library->UnregisterFunction(runtime_stage_->GetEntrypoint(),
                                ShaderStage::kFragment);
 
    function = nullptr;
  }
 
  if (!function) {
    std::promise<bool> promise;
    auto future = promise.get_future();
 
    library->RegisterFunction(
        runtime_stage_->GetEntrypoint(),
        ToShaderStage(runtime_stage_->GetShaderStage()),
        runtime_stage_->GetCodeMapping(),
        fml::MakeCopyable([promise = std::move(promise)](bool result) mutable {
          promise.set_value(result);
        }));
 
    if (!future.get()) {
      VALIDATION_LOG << "Failed to build runtime effect (entry point: "
                     << runtime_stage_->GetEntrypoint() << ")";
      return false;
    }
 
    function = library->GetFunction(runtime_stage_->GetEntrypoint(),
                                    ShaderStage::kFragment);
    if (!function) {
      VALIDATION_LOG
          << "Failed to fetch runtime effect function immediately after "
             "registering it (entry point: "
          << runtime_stage_->GetEntrypoint() << ")";
      return false;
    }
 
    runtime_stage_->SetClean();
  }
 
  //--------------------------------------------------------------------------
  /// Resolve geometry.
  ///
 
  auto geometry_result =
      GetGeometry()->GetPositionBuffer(renderer, entity, pass);
 
  //--------------------------------------------------------------------------
  /// Get or create runtime stage pipeline.
  ///
 
  const auto& caps = context->GetCapabilities();
  const auto color_attachment_format = caps->GetDefaultColorFormat();
  const auto stencil_attachment_format = caps->GetDefaultStencilFormat();
 
  using VS = RuntimeEffectVertexShader;
  PipelineDescriptor desc;
  desc.SetLabel("Runtime Stage");
  desc.AddStageEntrypoint(
      library->GetFunction(VS::kEntrypointName, ShaderStage::kVertex));
  desc.AddStageEntrypoint(library->GetFunction(runtime_stage_->GetEntrypoint(),
                                               ShaderStage::kFragment));
  auto vertex_descriptor = std::make_shared<VertexDescriptor>();
  vertex_descriptor->SetStageInputs(VS::kAllShaderStageInputs,
                                    VS::kInterleavedBufferLayout);
  desc.SetVertexDescriptor(std::move(vertex_descriptor));
  desc.SetColorAttachmentDescriptor(
      0u, {.format = color_attachment_format, .blending_enabled = true});
 
  StencilAttachmentDescriptor stencil0;
  stencil0.stencil_compare = CompareFunction::kEqual;
  desc.SetStencilAttachmentDescriptors(stencil0);
  desc.SetStencilPixelFormat(stencil_attachment_format);
 
  auto options = OptionsFromPassAndEntity(pass, entity);
  if (geometry_result.prevent_overdraw) {
    options.stencil_compare = CompareFunction::kEqual;
    options.stencil_operation = StencilOperation::kIncrementClamp;
  }
  options.primitive_type = geometry_result.type;
  options.ApplyToPipelineDescriptor(desc);
 
  auto pipeline = context->GetPipelineLibrary()->GetPipeline(desc).Get();
  if (!pipeline) {
    VALIDATION_LOG << "Failed to get or create runtime effect pipeline.";
    return false;
  }
 
  Command cmd;
  DEBUG_COMMAND_INFO(cmd, "RuntimeEffectContents");
  cmd.pipeline = pipeline;
  cmd.stencil_reference = entity.GetClipDepth();
  cmd.BindVertices(std::move(geometry_result.vertex_buffer));
 
  //--------------------------------------------------------------------------
  /// Vertex stage uniforms.
  ///
 
  VS::FrameInfo frame_info;
  frame_info.mvp = geometry_result.transform;
  VS::BindFrameInfo(cmd, pass.GetTransientsBuffer().EmplaceUniform(frame_info));
 
  //--------------------------------------------------------------------------
  /// Fragment stage uniforms.
  ///
 
  size_t minimum_sampler_index = 100000000;
  size_t buffer_index = 0;
  size_t buffer_offset = 0;
  for (const auto& uniform : runtime_stage_->GetUniforms()) {
    std::shared_ptr<ShaderMetadata> metadata = MakeShaderMetadata(uniform);
 
    switch (uniform.type) {
      case kSampledImage: {
        // Sampler uniforms are ordered in the IPLR according to their
        // declaration and the uniform location reflects the correct offset to
        // be mapped to - except that it may include all proceeding float
        // uniforms. For example, a float sampler that comes after 4 float
        // uniforms may have a location of 4. To convert to the actual offset we
        // need to find the largest location assigned to a float uniform and
        // then subtract this from all uniform locations. This is more or less
        // the same operation we previously performed in the shader compiler.
        minimum_sampler_index =
            std::min(minimum_sampler_index, uniform.location);
        break;
      }
      case kFloat: {
        size_t alignment =
            std::max(uniform.bit_width / 8, DefaultUniformAlignment());
        auto buffer_view = pass.GetTransientsBuffer().Emplace(
            uniform_data_->data() + buffer_offset, uniform.GetSize(),
            alignment);
 
        ShaderUniformSlot uniform_slot;
        uniform_slot.name = uniform.name.c_str();
        uniform_slot.ext_res_0 = uniform.location;
        cmd.BindResource(ShaderStage::kFragment, uniform_slot, metadata,
                         buffer_view);
        buffer_index++;
        buffer_offset += uniform.GetSize();
        break;
      }
      case kBoolean:
      case kSignedByte:
      case kUnsignedByte:
      case kSignedShort:
      case kUnsignedShort:
      case kSignedInt:
      case kUnsignedInt:
      case kSignedInt64:
      case kUnsignedInt64:
      case kHalfFloat:
      case kDouble:
        VALIDATION_LOG << "Unsupported uniform type for " << uniform.name
                       << ".";
        return true;
    }
  }
 
  size_t sampler_index = 0;
  for (const auto& uniform : runtime_stage_->GetUniforms()) {
    std::shared_ptr<ShaderMetadata> metadata = MakeShaderMetadata(uniform);
 
    switch (uniform.type) {
      case kSampledImage: {
        FML_DCHECK(sampler_index < texture_inputs_.size());
        auto& input = texture_inputs_[sampler_index];
 
        auto sampler =
            context->GetSamplerLibrary()->GetSampler(input.sampler_descriptor);
 
        SampledImageSlot image_slot;
        image_slot.name = uniform.name.c_str();
        image_slot.texture_index = uniform.location - minimum_sampler_index;
        cmd.BindResource(ShaderStage::kFragment, image_slot, *metadata,
                         input.texture, sampler);
 
        sampler_index++;
        break;
      }
      default:
        continue;
    }
  }
 
  pass.AddCommand(std::move(cmd));
 
  if (geometry_result.prevent_overdraw) {
    auto restore = ClipRestoreContents();
    restore.SetRestoreCoverage(GetCoverage(entity));
    return restore.Render(renderer, entity, pass);
  }
  return true;
}

References impeller::RenderPass::AddCommand(), impeller::PipelineDescriptor::AddStageEntrypoint(), impeller::Command::BindResource(), impeller::Command::BindVertices(), DEBUG_COMMAND_INFO, impeller::DefaultUniformAlignment(), impeller::HostBuffer::Emplace(), impeller::HostBuffer::EmplaceUniform(), impeller::ShaderUniformSlot::ext_res_0, impeller::Entity::GetClipDepth(), impeller::ContentContext::GetContext(), impeller::ColorSourceContents::GetCoverage(), impeller::ColorSourceContents::GetGeometry(), impeller::RenderPass::GetTransientsBuffer(), impeller::kBoolean, impeller::kDouble, impeller::kEqual, impeller::kFloat, impeller::kFragment, impeller::kHalfFloat, impeller::kIncrementClamp, impeller::kSampledImage, impeller::kSignedByte, impeller::kSignedInt, impeller::kSignedInt64, impeller::kSignedShort, impeller::kUnsignedByte, impeller::kUnsignedInt, impeller::kUnsignedInt64, impeller::kUnsignedShort, impeller::kVertex, impeller::Context::kVulkan, impeller::MakeShaderMetadata(), impeller::ShaderUniformSlot::name, impeller::SampledImageSlot::name, impeller::OptionsFromPassAndEntity(), impeller::Command::pipeline, impeller::PipelineDescriptor::SetColorAttachmentDescriptor(), impeller::PipelineDescriptor::SetLabel(), impeller::PipelineDescriptor::SetStencilAttachmentDescriptors(), impeller::PipelineDescriptor::SetStencilPixelFormat(), impeller::PipelineDescriptor::SetVertexDescriptor(), impeller::StencilAttachmentDescriptor::stencil_compare, impeller::Command::stencil_reference, impeller::SampledImageSlot::texture_index, impeller::ToShaderStage(), and VALIDATION_LOG.

SetRuntimeStage()

void impeller::RuntimeEffectContents::SetRuntimeStage

(

std::shared_ptr< RuntimeStage >

runtime_stage

)

Definition at line 25 of file runtime_effect_contents.cc.

                                               {
  runtime_stage_ = std::move(runtime_stage);
}

SetTextureInputs()

void impeller::RuntimeEffectContents::SetTextureInputs

(

std::vector< TextureInput >

texture_inputs

)

Definition at line 35 of file runtime_effect_contents.cc.

                                            {
  texture_inputs_ = std::move(texture_inputs);
}

SetUniformData()

void impeller::RuntimeEffectContents::SetUniformData

(

std::shared_ptr< std::vector< uint8_t >>

uniform_data

)

Definition at line 30 of file runtime_effect_contents.cc.

                                                    {
  uniform_data_ = std::move(uniform_data);
}

---

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

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