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	Render (const ContentContext &renderer, const Entity &entity, RenderPass &pass) const override
bool	BootstrapShader (const ContentContext &renderer) const
	Load the runtime effect and ensure a default PSO is initialized.
Public Member Functions inherited from impeller::ColorSourceContents
	ColorSourceContents ()
	~ColorSourceContents () override
void	SetGeometry (const Geometry *geometry)
	Set the geometry that this contents will use to render.
const 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
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.
void	SetInheritedOpacity (Scalar opacity) override
	Inherit the provided opacity.
Public Member Functions inherited from impeller::Contents
	Contents ()
virtual	~Contents ()
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 Matrix &transform) 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 std::optional< Snapshot >	RenderToSnapshot (const ContentContext &renderer, const Entity &entity, const SnapshotOptions &options) 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).
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 bool	ApplyColorFilter (const ColorFilterProc &color_filter_proc)
	If possible, applies a color filter to this contents inputs on the CPU.

Static Public Member Functions
static BufferView	EmplaceUniform (const uint8_t *source_data, HostBuffer &host_buffer, const RuntimeUniformDescription &uniform)
Static Public Member Functions inherited from impeller::ColorSourceContents
template<typename VertexShaderT >
static bool	DrawGeometry (const Contents *contents, const Geometry *geometry, const ContentContext &renderer, const Entity &entity, RenderPass &pass, const PipelineBuilderCallback &pipeline_callback, typename VertexShaderT::FrameInfo frame_info, const BindFragmentCallback &bind_fragment_callback, bool force_stencil=false, const CreateGeometryCallback &create_geom_callback=DefaultCreateGeometryCallback)
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::ColorSourceContents
using	BindFragmentCallback = std::function< bool(RenderPass &pass)>
using	PipelineBuilderCallback = std::function< PipelineRef(ContentContextOptions)>
using	CreateGeometryCallback = std::function< GeometryResult(const ContentContext &renderer, const Entity &entity, RenderPass &pass, const Geometry *geom)>
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)>
Protected Member Functions inherited from impeller::ColorSourceContents
bool	AppliesAlphaForStrokeCoverage (const Matrix &transform) const
	Whether the entity should be treated as non-opaque due to stroke geometry requiring alpha for coverage.
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, bool force_stencil=false, const CreateGeometryCallback &create_geom_callback=DefaultCreateGeometryCallback) const
Static Protected Member Functions inherited from impeller::ColorSourceContents
static GeometryResult	DefaultCreateGeometryCallback (const ContentContext &renderer, const Entity &entity, RenderPass &pass, const Geometry *geom)

Detailed Description

Definition at line 18 of file runtime_effect_contents.h.

Member Function Documentation

BootstrapShader()

bool impeller::RuntimeEffectContents::BootstrapShader

(

const ContentContext &

renderer

)

const

Load the runtime effect and ensure a default PSO is initialized.

Definition at line 121 of file runtime_effect_contents.cc.

                                          {
  if (!RegisterShader(renderer)) {
    return false;
  }
  ContentContextOptions options;
  options.color_attachment_pixel_format =
      renderer.GetContext()->GetCapabilities()->GetDefaultColorFormat();
  CreatePipeline(renderer, options, /*async=*/true);
  return true;
}

References impeller::ContentContextOptions::color_attachment_pixel_format, and impeller::ContentContext::GetContext().

Referenced by flutter::SnapshotControllerImpeller::CacheRuntimeStage().

EmplaceUniform()

BufferView impeller::RuntimeEffectContents::EmplaceUniform ( const uint8_t *  source_data, HostBuffer &  host_buffer, const RuntimeUniformDescription &  uniform  )

static

Copies the uniform data into the host buffer.

If the uniform has a padding_layout, it is used to repack the data.

Parameters

source_data	The pointer to the start of the uniform data in the source.
host_buffer	The host buffer to emplace the uniform data into.
uniform	The description of the uniform being emplaced.

Definition at line 28 of file runtime_effect_contents.cc.

                                              {
  size_t minimum_uniform_alignment =
      data_host_buffer.GetMinimumUniformAlignment();
  size_t alignment = std::max(uniform.bit_width / 8, minimum_uniform_alignment);
 
  if (uniform.padding_layout.empty()) {
    return data_host_buffer.Emplace(source_data, uniform.GetGPUSize(),
                                    alignment);
  }
 
  // If the uniform has a padding layout, we need to repack the data.
  // We can do this by using the EmplaceProc to write directly to the
  // HostBuffer.
  return data_host_buffer.Emplace(
      uniform.GetGPUSize(), alignment,
      [&uniform, source_data](uint8_t* destination) {
        size_t count = uniform.array_elements.value_or(1);
        if (count == 0) {
          // Make sure to run at least once.
          count = 1;
        }
        size_t uniform_byte_index = 0u;
        size_t struct_float_index = 0u;
        auto* float_destination = reinterpret_cast<float*>(destination);
        auto* float_source = reinterpret_cast<const float*>(source_data);
 
        for (size_t i = 0; i < count; i++) {
          for (RuntimePaddingType byte_type : uniform.padding_layout) {
            if (byte_type == RuntimePaddingType::kPadding) {
              float_destination[struct_float_index++] = 0.f;
            } else {
              FML_DCHECK(byte_type == RuntimePaddingType::kFloat);
              float_destination[struct_float_index++] =
                  float_source[uniform_byte_index++];
            }
          }
        }
      });
}

References impeller::RuntimeUniformDescription::bit_width, impeller::HostBuffer::Emplace(), FML_DCHECK, impeller::RuntimeUniformDescription::GetGPUSize(), impeller::HostBuffer::GetMinimumUniformAlignment(), i, impeller::kFloat, impeller::kPadding, and impeller::RuntimeUniformDescription::padding_layout.

Referenced by impeller::testing::TEST_P().

Render()

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

overridevirtual

Get or register shader. Flutter will do this when the runtime effect is first loaded, but this check is added to supporting testing of the Aiks API and non-flutter usage of Impeller.

Fragment stage uniforms.

Now that the descriptor set layouts are known, get the pipeline.

Implements impeller::Contents.

Definition at line 240 of file runtime_effect_contents.cc.

                                                           {
  const std::shared_ptr<Context>& context = renderer.GetContext();
  const std::shared_ptr<ShaderLibrary>& library = context->GetShaderLibrary();
 
  //--------------------------------------------------------------------------
  /// Get or register shader. Flutter will do this when the runtime effect
  /// is first loaded, but this check is added to supporting testing of the
  /// Aiks API and non-flutter usage of Impeller.
  ///
  if (!RegisterShader(renderer)) {
    return false;
  }
 
  //--------------------------------------------------------------------------
  /// Fragment stage uniforms.
  ///
  BindFragmentCallback bind_callback = [this, &renderer,
                                        &context](RenderPass& pass) {
    size_t buffer_index = 0;
    size_t buffer_offset = 0;
    size_t sampler_location = 0;
    size_t buffer_location = 0;
 
    // 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
    // uniforms of a different type. For example, a texture sampler that comes
    // after 4 float uniforms may have a location of 4. Since we know that
    // the declarations are already ordered, we can track the uniform location
    // ourselves.
    auto& data_host_buffer = renderer.GetTransientsDataBuffer();
    for (const auto& uniform : runtime_stage_->GetUniforms()) {
      std::unique_ptr<ShaderMetadata> metadata = MakeShaderMetadata(uniform);
      switch (uniform.type) {
        case kSampledImage: {
          FML_DCHECK(sampler_location < texture_inputs_.size());
          auto& input = texture_inputs_[sampler_location];
 
          raw_ptr<const Sampler> sampler =
              context->GetSamplerLibrary()->GetSampler(
                  input.sampler_descriptor);
 
          SampledImageSlot image_slot;
          image_slot.name = uniform.name.c_str();
          image_slot.binding = uniform.binding;
          image_slot.texture_index = sampler_location;
          pass.BindDynamicResource(ShaderStage::kFragment,
                                   DescriptorType::kSampledImage, image_slot,
                                   std::move(metadata), input.texture, sampler);
          sampler_location++;
          break;
        }
        case kFloat: {
          FML_DCHECK(renderer.GetContext()->GetBackendType() !=
                     Context::BackendType::kVulkan)
              << "Uniform " << uniform.name
              << " had unexpected type kFloat for Vulkan backend.";
 
          BufferView buffer_view = EmplaceUniform(
              uniform_data_->data() + buffer_offset, data_host_buffer, uniform);
 
          ShaderUniformSlot uniform_slot;
          uniform_slot.name = uniform.name.c_str();
          uniform_slot.ext_res_0 = buffer_location;
          pass.BindDynamicResource(ShaderStage::kFragment,
                                   DescriptorType::kUniformBuffer, uniform_slot,
                                   std::move(metadata), std::move(buffer_view));
          buffer_index++;
          buffer_offset += uniform.GetDartSize();
          buffer_location++;
          break;
        }
        case kStruct: {
          FML_DCHECK(renderer.GetContext()->GetBackendType() ==
                     Context::BackendType::kVulkan);
          ShaderUniformSlot uniform_slot;
          uniform_slot.binding = uniform.location;
          uniform_slot.name = uniform.name.c_str();
 
          pass.BindResource(
              ShaderStage::kFragment, DescriptorType::kUniformBuffer,
              uniform_slot, nullptr,
              EmplaceUniform(uniform_data_->data(), data_host_buffer, uniform));
        }
      }
    }
 
    return true;
  };
 
  /// Now that the descriptor set layouts are known, get the pipeline.
  using VS = RuntimeEffectVertexShader;
 
  PipelineBuilderCallback pipeline_callback =
      [&](ContentContextOptions options) {
        // Pipeline creation callback for the cache handler to call.
        return renderer.GetCachedRuntimeEffectPipeline(
            runtime_stage_->GetEntrypoint(), options, [&]() {
              return CreatePipeline(renderer, options, /*async=*/false);
            });
      };
 
  return ColorSourceContents::DrawGeometry<VS>(renderer, entity, pass,
                                               pipeline_callback,
                                               VS::FrameInfo{}, bind_callback);
}

References impeller::RenderPass::BindDynamicResource(), impeller::ShaderUniformSlot::binding, impeller::SampledImageSlot::binding, impeller::RenderPass::BindResource(), buffer_view, impeller::ShaderUniformSlot::ext_res_0, FML_DCHECK, impeller::ContentContext::GetCachedRuntimeEffectPipeline(), impeller::ContentContext::GetContext(), impeller::ContentContext::GetTransientsDataBuffer(), input(), impeller::kFloat, impeller::kSampledImage, impeller::kStruct, impeller::MakeShaderMetadata(), impeller::ShaderUniformSlot::name, impeller::SampledImageSlot::name, and impeller::SampledImageSlot::texture_index.

SetRuntimeStage()

void impeller::RuntimeEffectContents::SetRuntimeStage

(

std::shared_ptr< RuntimeStage >

runtime_stage

)

Definition at line 71 of file runtime_effect_contents.cc.

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

Referenced by flutter::SnapshotControllerImpeller::CacheRuntimeStage().

SetTextureInputs()

void impeller::RuntimeEffectContents::SetTextureInputs

(

std::vector< TextureInput >

texture_inputs

)

Definition at line 81 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 76 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