LiteFX::Rendering::IDescriptorLayout Class Reference

Describes a the layout of a single descriptor within a DescriptorSet. More...

#include <rendering_api.hpp>

Inherits LiteFX::Rendering::IBufferLayout.

Inherited by LiteFX::Rendering::Backends::DirectX12DescriptorLayout, and LiteFX::Rendering::Backends::VulkanDescriptorLayout.

Public Member Functions
	~IDescriptorLayout () noexcept override=default
virtual DescriptorType	descriptorType () const noexcept=0
	Returns the type of the descriptor.
virtual UInt32	descriptors () const noexcept=0
	Returns the number of descriptors in the descriptor array.
virtual bool	unbounded () const noexcept=0
	Returns true, if the descriptor defines an unbounded descriptor array.
virtual const ISampler *	staticSampler () const noexcept=0
	If the descriptor describes a static sampler, this method returns the state of the sampler. Otherwise, it returns nullptr.
Public Member Functions inherited from LiteFX::Rendering::IBufferLayout
virtual	~IBufferLayout () noexcept=default
virtual size_t	elementSize () const noexcept=0
	Returns the size of a single element within the buffer.
virtual UInt32	binding () const noexcept=0
	Returns the binding point, the buffer will be bound to.
virtual BufferType	type () const noexcept=0
	Returns the buffer type of the buffer.

Protected Member Functions
	IDescriptorLayout () noexcept=default
	IDescriptorLayout (IDescriptorLayout &&) noexcept=default
	IDescriptorLayout (const IDescriptorLayout &)=default
IDescriptorLayout &	operator= (IDescriptorLayout &&) noexcept=default
IDescriptorLayout &	operator= (const IDescriptorLayout &)=default
Protected Member Functions inherited from LiteFX::Rendering::IBufferLayout
	IBufferLayout () noexcept=default
	IBufferLayout (IBufferLayout &&) noexcept=default
	IBufferLayout (const IBufferLayout &)=default
IBufferLayout &	operator= (IBufferLayout &&) noexcept=default
IBufferLayout &	operator= (const IBufferLayout &)=default

Detailed Description

Describes a the layout of a single descriptor within a DescriptorSet.

A common metaphor for a descriptor to think of it as a "pointer for the GPU". Basically, a descriptor points to a buffer in a shader. A descriptor can have different types and sizes. The types a descriptor can have are described by the DescriptorType.

If the descriptor is a sampler, it can either be a dynamic or static sampler. A dynamic sampler needs to be bound during runtime just like any other descriptor by calling IDescriptorSet::update. A static sampler is defined alongside the descriptor layout and is automatically set when the pipeline that uses the descriptor layout gets bound. In this case, the descriptor must not be updated with another sampler. If a descriptor layout describes a static sampler, the IDescriptorLayout::staticSampler returns a pointer to the static sampler state.

Typically, a descriptor "points" to a singular buffer, i.e. a scalar. However, a descriptor can also resemble an array. In this case, IDescriptorLayout::descriptors returns the number of elements in the array. If the size of the array is not known beforehand, the descriptor can be defined as unbounded, causing the IDescriptorLayout::unbounded property to return true. In this case, the number of descriptors defines the upper limit for the actual descriptor count that can be allocated for the array when calling IDescriptorSetLayout::allocate.

See also

DescriptorSetLayout

Constructor & Destructor Documentation

IDescriptorLayout() [1/3]

LiteFX::Rendering::IDescriptorLayout::IDescriptorLayout ( )

protecteddefaultnoexcept

IDescriptorLayout() [2/3]

LiteFX::Rendering::IDescriptorLayout::IDescriptorLayout ( IDescriptorLayout && )

protecteddefaultnoexcept

IDescriptorLayout() [3/3]

LiteFX::Rendering::IDescriptorLayout::IDescriptorLayout ( const IDescriptorLayout & )

protecteddefault

~IDescriptorLayout()

LiteFX::Rendering::IDescriptorLayout::~IDescriptorLayout ( )

overridedefaultnoexcept

Member Function Documentation

descriptors()

virtual UInt32 LiteFX::Rendering::IDescriptorLayout::descriptors ( ) const

pure virtualnoexcept

Returns the number of descriptors in the descriptor array.

If unbounded is set to true, the descriptor count defines the upper limit for the number of descriptors that can be allocated for in the array.

Returns

The number of descriptors in the descriptor array.

See also

IDescriptorLayout

Implemented in LiteFX::Rendering::Backends::DirectX12DescriptorLayout, and LiteFX::Rendering::Backends::VulkanDescriptorLayout.

descriptorType()

virtual DescriptorType LiteFX::Rendering::IDescriptorLayout::descriptorType ( ) const

pure virtualnoexcept

Returns the type of the descriptor.

Returns

The type of the descriptor.

Implemented in LiteFX::Rendering::Backends::DirectX12DescriptorLayout, and LiteFX::Rendering::Backends::VulkanDescriptorLayout.

operator=() [1/2]

IDescriptorLayout & LiteFX::Rendering::IDescriptorLayout::operator= ( const IDescriptorLayout & )

protecteddefault

operator=() [2/2]

IDescriptorLayout & LiteFX::Rendering::IDescriptorLayout::operator= ( IDescriptorLayout && )

protecteddefaultnoexcept

staticSampler()

virtual const ISampler * LiteFX::Rendering::IDescriptorLayout::staticSampler ( ) const

pure virtualnoexcept

If the descriptor describes a static sampler, this method returns the state of the sampler. Otherwise, it returns nullptr.

Static samplers are called immutable samplers in Vulkan and describe sampler states, that are defined along the pipeline layout. While they do occupy a descriptor, they must not be bound explicitly. Instead, static samplers are automatically bound if the pipeline gets used. If a static sampler is set, the descriptorType must be set to DescriptorType::Sampler.

Returns

The state of the static sampler, or nullptr, if the descriptor is not a static sampler.

Implemented in LiteFX::Rendering::Backends::DirectX12DescriptorLayout, and LiteFX::Rendering::Backends::VulkanDescriptorLayout.

unbounded()

virtual bool LiteFX::Rendering::IDescriptorLayout::unbounded ( ) const

pure virtualnoexcept

Returns true, if the descriptor defines an unbounded descriptor array.

Returns

true, if the descriptor defines an unbounded descriptor array, false otherwise.

See also

descriptors

Implemented in LiteFX::Rendering::Backends::DirectX12DescriptorLayout, and LiteFX::Rendering::Backends::VulkanDescriptorLayout.