impeller::DlAtlasGeometry Class Reference

A wrapper around data provided by a drawAtlas call. More...

#include <dl_atlas_geometry.h>

Inheritance diagram for impeller::DlAtlasGeometry:

Public Member Functions
	DlAtlasGeometry (const std::shared_ptr< Texture > &atlas, const RSTransform *xform, const flutter::DlRect *tex, const flutter::DlColor *colors, size_t count, BlendMode mode, const SamplerDescriptor &sampling, std::optional< Rect > cull_rect)
	~DlAtlasGeometry ()
bool	ShouldUseBlend () const override
	Whether the blend shader should be used. More...
bool	ShouldSkip () const override
VertexBuffer	CreateSimpleVertexBuffer (HostBuffer &host_buffer) const override
VertexBuffer	CreateBlendVertexBuffer (HostBuffer &host_buffer) const override
Rect	ComputeBoundingBox () const override
std::shared_ptr< Texture >	GetAtlas () const override
const SamplerDescriptor &	GetSamplerDescriptor () const override
BlendMode	GetBlendMode () const override

Detailed Description

A wrapper around data provided by a drawAtlas call.

Definition at line 17 of file dl_atlas_geometry.h.

Constructor & Destructor Documentation

DlAtlasGeometry()

impeller::DlAtlasGeometry::DlAtlasGeometry	(	const std::shared_ptr< Texture > &	atlas,
		const RSTransform *	xform,
		const flutter::DlRect *	tex,
		const flutter::DlColor *	colors,
		size_t	count,
		BlendMode	mode,
		const SamplerDescriptor &	sampling,
		std::optional< Rect >	cull_rect
	)

Definition at line 18 of file dl_atlas_geometry.cc.

    : atlas_(atlas),
      xform_(xform),
      tex_(tex),
      colors_(colors),
      count_(count),
      mode_(mode),
      sampling_(sampling),
      cull_rect_(cull_rect) {}

~DlAtlasGeometry()

impeller::DlAtlasGeometry::~DlAtlasGeometry ( )

default

Member Function Documentation

ComputeBoundingBox()

Rect impeller::DlAtlasGeometry::ComputeBoundingBox ( ) const

overridevirtual

Implements impeller::AtlasGeometry.

Definition at line 45 of file dl_atlas_geometry.cc.

                                               {
  if (cull_rect_.has_value()) {
    return cull_rect_.value();
  }
  Rect bounding_box;
  for (size_t i = 0; i < count_; i++) {
    auto bounds = xform_[i].GetBounds(tex_[i].GetSize());
    bounding_box = Rect::Union(bounding_box, bounds);
  }
  cull_rect_ = bounding_box;
  return bounding_box;
}

References impeller::RSTransform::GetBounds(), and impeller::TRect< Scalar >::Union().

CreateBlendVertexBuffer()

VertexBuffer impeller::DlAtlasGeometry::CreateBlendVertexBuffer ( HostBuffer &  host_buffer ) const

overridevirtual

Implements impeller::AtlasGeometry.

Definition at line 103 of file dl_atlas_geometry.cc.

                                   {
  using VS = PorterDuffBlendVertexShader;
 
  constexpr size_t indices[6] = {0, 1, 2, 1, 2, 3};
 
  auto buffer_view = host_buffer.Emplace(
      sizeof(VS::PerVertexData) * count_ * 6, alignof(VS::PerVertexData),
      [&](uint8_t* raw_data) {
        VS::PerVertexData* data =
            reinterpret_cast<VS::PerVertexData*>(raw_data);
        int offset = 0;
        auto texture_size = atlas_->GetSize();
        for (auto i = 0u; i < count_; i++) {
          flutter::DlRect sample_rect = tex_[i];
          auto points = sample_rect.GetPoints();
          auto transformed_points = xform_[i].GetQuad(sample_rect.GetSize());
          for (size_t j = 0; j < 6; j++) {
            data[offset].vertices = transformed_points[indices[j]];
            data[offset].texture_coords = points[indices[j]] / texture_size;
            data[offset].color =
                skia_conversions::ToColor(colors_[i]).Premultiply();
            offset += 1;
          }
        }
      });
 
  return VertexBuffer{
      .vertex_buffer = buffer_view,
      .index_buffer = {},
      .vertex_count = count_ * 6,
      .index_type = IndexType::kNone,
  };
}

References buffer_view, data, impeller::HostBuffer::Emplace(), impeller::RSTransform::GetQuad(), impeller::kNone, offset, impeller::Color::Premultiply(), impeller::skia_conversions::ToColor(), and impeller::VertexBuffer::vertex_buffer.

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

CreateSimpleVertexBuffer()

VertexBuffer impeller::DlAtlasGeometry::CreateSimpleVertexBuffer ( HostBuffer &  host_buffer ) const

overridevirtual

Implements impeller::AtlasGeometry.

Definition at line 70 of file dl_atlas_geometry.cc.

                                   {
  using VS = TextureFillVertexShader;
 
  constexpr size_t indices[6] = {0, 1, 2, 1, 2, 3};
 
  auto buffer_view = host_buffer.Emplace(
      sizeof(VS::PerVertexData) * count_ * 6, alignof(VS::PerVertexData),
      [&](uint8_t* raw_data) {
        VS::PerVertexData* data =
            reinterpret_cast<VS::PerVertexData*>(raw_data);
        int offset = 0;
        auto texture_size = atlas_->GetSize();
        for (auto i = 0u; i < count_; i++) {
          flutter::DlRect sample_rect = tex_[i];
          auto points = sample_rect.GetPoints();
          auto transformed_points = xform_[i].GetQuad(sample_rect.GetSize());
          for (size_t j = 0; j < 6; j++) {
            data[offset].position = transformed_points[indices[j]];
            data[offset].texture_coords = points[indices[j]] / texture_size;
            offset += 1;
          }
        }
      });
 
  return VertexBuffer{
      .vertex_buffer = buffer_view,
      .index_buffer = {},
      .vertex_count = count_ * 6,
      .index_type = IndexType::kNone,
  };
}

References buffer_view, data, impeller::HostBuffer::Emplace(), impeller::RSTransform::GetQuad(), impeller::kNone, offset, and impeller::VertexBuffer::vertex_buffer.

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

GetAtlas()

std::shared_ptr< Texture > impeller::DlAtlasGeometry::GetAtlas ( ) const

overridevirtual

Implements impeller::AtlasGeometry.

Definition at line 58 of file dl_atlas_geometry.cc.

                                                       {
  return atlas_;
}

GetBlendMode()

BlendMode impeller::DlAtlasGeometry::GetBlendMode ( ) const

overridevirtual

Implements impeller::AtlasGeometry.

Definition at line 66 of file dl_atlas_geometry.cc.

                                              {
  return mode_;
}

GetSamplerDescriptor()

const SamplerDescriptor & impeller::DlAtlasGeometry::GetSamplerDescriptor ( ) const

overridevirtual

Implements impeller::AtlasGeometry.

Definition at line 62 of file dl_atlas_geometry.cc.

                                                                     {
  return sampling_;
}

ShouldSkip()

bool impeller::DlAtlasGeometry::ShouldSkip ( ) const

overridevirtual

Implements impeller::AtlasGeometry.

Definition at line 41 of file dl_atlas_geometry.cc.

                                       {
  return atlas_ == nullptr || (ShouldUseBlend() && mode_ == BlendMode::kClear);
}

References impeller::kClear, and ShouldUseBlend().

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

ShouldUseBlend()

bool impeller::DlAtlasGeometry::ShouldUseBlend ( ) const

overridevirtual

Whether the blend shader should be used.

Implements impeller::AtlasGeometry.

Definition at line 37 of file dl_atlas_geometry.cc.

                                           {
  return colors_ != nullptr && mode_ != BlendMode::kSource;
}

References impeller::kSource.

Referenced by ShouldSkip(), and impeller::testing::TEST_P().

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

• impeller/display_list/dl_atlas_geometry.h
• impeller/display_list/dl_atlas_geometry.cc