impeller::HostBuffer Class Reference

#include <host_buffer.h>

Inheritance diagram for impeller::HostBuffer:

Public Types
using	EmplaceProc = std::function< void(uint8_t *buffer)>

Public Member Functions
virtual	~HostBuffer ()
void	SetLabel (std::string label)
template<class UniformType , class = std::enable_if_t<std::is_standard_layout_v<UniformType>>>
BufferView	EmplaceUniform (const UniformType &uniform)
	Emplace uniform data onto the host buffer. Ensure that backend specific uniform alignment requirements are respected. More...
template<class StorageBufferType , class = std::enable_if_t<std::is_standard_layout_v<StorageBufferType>>>
BufferView	EmplaceStorageBuffer (const StorageBufferType &buffer)
	Emplace storage buffer data onto the host buffer. Ensure that backend specific uniform alignment requirements are respected. More...
template<class BufferType , class = std::enable_if_t<std::is_standard_layout_v<BufferType>>>
BufferView	Emplace (const BufferType &buffer)
	Emplace non-uniform data (like contiguous vertices) onto the host buffer. More...
BufferView	Emplace (const void *buffer, size_t length, size_t align)
BufferView	Emplace (size_t length, size_t align, const EmplaceProc &cb)
	Emplaces undefined data onto the managed buffer and gives the caller a chance to update it using the specified callback. The buffer is guaranteed to have enough space for length bytes. It is the responsibility of the caller to not exceed the bounds of the buffer returned in the EmplaceProc. More...
void	Reset ()
	Resets the contents of the HostBuffer to nothing so it can be reused. More...
size_t	GetSize () const
	Returns the size of the HostBuffer in memory in bytes. More...
Public Member Functions inherited from impeller::Allocation
	Allocation ()
	~Allocation ()
uint8_t *	GetBuffer () const
size_t	GetLength () const
size_t	GetReservedLength () const
bool	Truncate (size_t length, bool npot=true)
Public Member Functions inherited from impeller::Buffer
virtual	~Buffer ()

Static Public Member Functions
static std::shared_ptr< HostBuffer >	Create ()
Static Public Member Functions inherited from impeller::Allocation
static uint32_t	NextPowerOfTwoSize (uint32_t x)

Detailed Description

Definition at line 20 of file host_buffer.h.

Member Typedef Documentation

EmplaceProc

using impeller::HostBuffer::EmplaceProc = std::function<void(uint8_t* buffer)>

Definition at line 98 of file host_buffer.h.

Constructor & Destructor Documentation

~HostBuffer()

impeller::HostBuffer::~HostBuffer ( )

virtualdefault

Member Function Documentation

Create()

std::shared_ptr< HostBuffer > impeller::HostBuffer::Create ( )

static

Definition at line 18 of file host_buffer.cc.

                                             {
  return std::shared_ptr<HostBuffer>(new HostBuffer());
}

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

Emplace() [1/3]

template<class BufferType , class = std::enable_if_t<std::is_standard_layout_v<BufferType>>>

BufferView impeller::HostBuffer::Emplace ( const BufferType &  buffer )

inline

Emplace non-uniform data (like contiguous vertices) onto the host buffer.

Parameters

[in]

buffer

The buffer data.

Template Parameters

BufferType

The type of the buffer data.

Returns

The buffer view.

Definition at line 87 of file host_buffer.h.

                                                             {
    return Emplace(reinterpret_cast<const void*>(&buffer),  // buffer
                   sizeof(BufferType),                      // size
                   alignof(BufferType)                      // alignment
    );
  }

Referenced by Emplace(), EmplaceStorageBuffer(), EmplaceUniform(), impeller::RuntimeEffectContents::Render(), and impeller::TextContents::Render().

Emplace() [2/3]

BufferView impeller::HostBuffer::Emplace	(	const void *	buffer,
		size_t	length,
		size_t	align
	)

Definition at line 30 of file host_buffer.cc.

                                             {
  if (align == 0 || (GetLength() % align) == 0) {
    return Emplace(buffer, length);
  }
 
  {
    auto pad = Emplace(nullptr, align - (GetLength() % align));
    if (!pad) {
      return {};
    }
  }
 
  return Emplace(buffer, length);
}

References Emplace(), and impeller::Allocation::GetLength().

Emplace() [3/3]

BufferView impeller::HostBuffer::Emplace	(	size_t	length,
		size_t	align,
		const EmplaceProc &	cb
	)

Emplaces undefined data onto the managed buffer and gives the caller a chance to update it using the specified callback. The buffer is guaranteed to have enough space for length bytes. It is the responsibility of the caller to not exceed the bounds of the buffer returned in the EmplaceProc.

Parameters

[in]

cb

A callback that will be passed a ptr to the underlying host buffer.

Returns

The buffer view.

Definition at line 59 of file host_buffer.cc.

                                                      {
  if (!cb) {
    return {};
  }
  auto old_length = GetLength();
  if (!Truncate(old_length + length)) {
    return {};
  }
  generation_++;
  cb(GetBuffer() + old_length);
 
  return BufferView{shared_from_this(), GetBuffer(), Range{old_length, length}};
}

References impeller::Allocation::GetBuffer(), impeller::Allocation::GetLength(), and impeller::Allocation::Truncate().

EmplaceStorageBuffer()

template<class StorageBufferType , class = std::enable_if_t<std::is_standard_layout_v<StorageBufferType>>>

BufferView impeller::HostBuffer::EmplaceStorageBuffer ( const StorageBufferType &  buffer )

inline

Emplace storage buffer data onto the host buffer. Ensure that backend specific uniform alignment requirements are respected.

Parameters

[in]

uniform

The storage buffer to emplace onto the buffer.

Template Parameters

StorageBufferType

The type of the shader storage buffer.

Returns

The buffer view.

Definition at line 65 of file host_buffer.h.

                                       {
    const auto alignment =
        std::max(alignof(StorageBufferType), DefaultUniformAlignment());
    return Emplace(&buffer,                    // buffer
                   sizeof(StorageBufferType),  // size
                   alignment                   // alignment
    );
  }

References impeller::DefaultUniformAlignment(), and Emplace().

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

EmplaceUniform()

template<class UniformType , class = std::enable_if_t<std::is_standard_layout_v<UniformType>>>

BufferView impeller::HostBuffer::EmplaceUniform ( const UniformType &  uniform )

inline

Emplace uniform data onto the host buffer. Ensure that backend specific uniform alignment requirements are respected.

Parameters

[in]

uniform

The uniform struct to emplace onto the buffer.

Template Parameters

UniformType

The type of the uniform struct.

Returns

The buffer view.

Definition at line 43 of file host_buffer.h.

                                                                      {
    const auto alignment =
        std::max(alignof(UniformType), DefaultUniformAlignment());
    return Emplace(reinterpret_cast<const void*>(&uniform),  // buffer
                   sizeof(UniformType),                      // size
                   alignment                                 // alignment
    );
  }

References impeller::DefaultUniformAlignment(), and Emplace().

Referenced by impeller::scene::CuboidGeometry::BindToCommand(), impeller::scene::UnlitMaterial::BindToCommand(), impeller::scene::UnskinnedVertexBufferGeometry::BindToCommand(), impeller::scene::SkinnedVertexBufferGeometry::BindToCommand(), ImGui_ImplImpeller_RenderDrawData(), impeller::RuntimeEffectContents::Render(), impeller::ClipContents::Render(), impeller::SolidRRectBlurContents::Render(), impeller::SolidColorContents::Render(), impeller::TextContents::Render(), impeller::ClipRestoreContents::Render(), and impeller::testing::TEST_P().

GetSize()

size_t impeller::HostBuffer::GetSize

(

)

const

Returns the size of the HostBuffer in memory in bytes.

Definition at line 97 of file host_buffer.cc.

                                 {
  return GetReservedLength();
}

References impeller::Allocation::GetReservedLength().

Reset()

void impeller::HostBuffer::Reset

(

)

Resets the contents of the HostBuffer to nothing so it can be reused.

Definition at line 90 of file host_buffer.cc.

                       {
  generation_ += 1;
  device_buffer_ = nullptr;
  bool did_truncate = Truncate(0);
  FML_CHECK(did_truncate);
}

References impeller::Allocation::Truncate().

SetLabel()

void impeller::HostBuffer::SetLabel

(

std::string

label

)

Definition at line 26 of file host_buffer.cc.

                                         {
  label_ = std::move(label);
}

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

• impeller/core/host_buffer.h
• impeller/core/host_buffer.cc