impeller::Snapshot Struct Reference

Represents a texture and its intended draw transform/sampler configuration. More...

#include <snapshot.h>

Public Member Functions
std::optional< Rect >	GetCoverage () const
std::optional< Matrix >	GetUVTransform () const
	Get the transform that converts screen space coordinates to the UV space of this snapshot. More...
std::optional< std::array< Point, 4 > >	GetCoverageUVs (const Rect &coverage) const
	Map a coverage rect to this filter input's UV space. Result order: Top left, top right, bottom left, bottom right. More...

Public Attributes
std::shared_ptr< Texture >	texture
Matrix	transform
	The transform that should be applied to this texture for rendering. More...
SamplerDescriptor	sampler_descriptor
Scalar	opacity = 1.0f

Detailed Description

Represents a texture and its intended draw transform/sampler configuration.

Definition at line 24 of file snapshot.h.

Member Function Documentation

GetCoverage()

std::optional< Rect > impeller::Snapshot::GetCoverage

(

)

const

Definition at line 11 of file snapshot.cc.

                                              {
  if (!texture) {
    return std::nullopt;
  }
  return Rect::MakeSize(texture->GetSize()).TransformBounds(transform);
}

References impeller::TRect< Scalar >::MakeSize(), texture, transform, and impeller::TRect< T >::TransformBounds().

GetCoverageUVs()

std::optional< std::array< Point, 4 > > impeller::Snapshot::GetCoverageUVs

(

const Rect &

coverage

)

const

Map a coverage rect to this filter input's UV space. Result order: Top left, top right, bottom left, bottom right.

Definition at line 26 of file snapshot.cc.

                                {
  auto uv_transform = GetUVTransform();
  if (!uv_transform.has_value()) {
    return std::nullopt;
  }
  return coverage.GetTransformedPoints(uv_transform.value());
}

References impeller::TRect< T >::GetTransformedPoints(), and GetUVTransform().

GetUVTransform()

std::optional< Matrix > impeller::Snapshot::GetUVTransform

(

)

const

Get the transform that converts screen space coordinates to the UV space of this snapshot.

Definition at line 18 of file snapshot.cc.

                                                   {
  if (!texture || texture->GetSize().IsEmpty()) {
    return std::nullopt;
  }
  return Matrix::MakeScale(1 / Vector2(texture->GetSize())) *
         transform.Invert();
}

References impeller::Matrix::Invert(), impeller::Matrix::MakeScale(), texture, and transform.

Referenced by GetCoverageUVs().

Member Data Documentation

opacity

Scalar impeller::Snapshot::opacity = 1.0f

Definition at line 35 of file snapshot.h.

Referenced by impeller::Entity::FromSnapshot().

sampler_descriptor

SamplerDescriptor impeller::Snapshot::sampler_descriptor

Initial value:

=
      SamplerDescriptor("Default Snapshot Sampler",
                        MinMagFilter::kLinear,
                        MinMagFilter::kLinear,
                        MipFilter::kNearest)

Definition at line 29 of file snapshot.h.

Referenced by impeller::Entity::FromSnapshot(), and impeller::Canvas::SaveLayer().

texture

std::shared_ptr<Texture> impeller::Snapshot::texture

Definition at line 25 of file snapshot.h.

Referenced by impeller::AdvancedBlend(), impeller::Entity::FromSnapshot(), GetCoverage(), impeller::TextureFilterInput::GetSnapshot(), GetUVTransform(), impeller::PipelineBlend(), impeller::Contents::RenderToSnapshot(), impeller::TextureContents::RenderToSnapshot(), impeller::TiledTextureContents::RenderToSnapshot(), and impeller::Canvas::SaveLayer().

transform

Matrix impeller::Snapshot::transform

The transform that should be applied to this texture for rendering.

Definition at line 27 of file snapshot.h.

Referenced by impeller::Entity::FromSnapshot(), GetCoverage(), GetUVTransform(), and impeller::Canvas::SaveLayer().

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

• impeller/renderer/snapshot.h
• impeller/renderer/snapshot.cc