#include <ShaderResourceGroupLayout.h>

Inherits AZStd::intrusive_base.

Public Member Functions
	AZ_RTTI (ShaderResourceGroupLayout, "{1F92C651-9B83-4379-AB5C-5201F1B2C278}")

	AZ_CLASS_ALLOCATOR (ShaderResourceGroupLayout, SystemAllocator)

bool	IsFinalized () const

void	Clear ()
	Clears the layout to an empty state. The layout must be finalized prior to usage.

bool	Finalize ()

void	SetName (const Name &name)

const Name &	GetName () const

const AZStd::string &	GetUniqueId () const

void	SetUniqueId (const AZStd::string &uniqueId)

void	SetShaderVariantKeyFallback (const Name &shaderConstantName, uint32_t bitSize)

void	AddStaticSampler (const ShaderInputStaticSamplerDescriptor &sampler)

void	AddShaderInput (const ShaderInputBufferDescriptor &buffer)

void	AddShaderInput (const ShaderInputImageDescriptor &image)

void	AddShaderInput (const ShaderInputBufferUnboundedArrayDescriptor &bufferUnboundedArray)

void	AddShaderInput (const ShaderInputImageUnboundedArrayDescriptor &imageUnboundedArray)

void	AddShaderInput (const ShaderInputSamplerDescriptor &sampler)

void	AddShaderInput (const ShaderInputConstantDescriptor &constant)

void	SetBindingSlot (uint32_t bindingSlot)

AZStd::span< const ShaderInputStaticSamplerDescriptor >	GetStaticSamplers () const
	Returns the full list of static samplers descriptors declared on the layout.

ShaderInputBufferIndex	FindShaderInputBufferIndex (const Name &name) const

ShaderInputImageIndex	FindShaderInputImageIndex (const Name &name) const

ShaderInputSamplerIndex	FindShaderInputSamplerIndex (const Name &name) const

ShaderInputConstantIndex	FindShaderInputConstantIndex (const Name &name) const

ShaderInputBufferUnboundedArrayIndex	FindShaderInputBufferUnboundedArrayIndex (const Name &name) const

ShaderInputImageUnboundedArrayIndex	FindShaderInputImageUnboundedArrayIndex (const Name &name) const

const ShaderInputBufferDescriptor &	GetShaderInput (ShaderInputBufferIndex index) const

const ShaderInputImageDescriptor &	GetShaderInput (ShaderInputImageIndex index) const

const ShaderInputSamplerDescriptor &	GetShaderInput (ShaderInputSamplerIndex index) const

const ShaderInputConstantDescriptor &	GetShaderInput (ShaderInputConstantIndex index) const

const ShaderInputBufferUnboundedArrayDescriptor &	GetShaderInput (ShaderInputBufferUnboundedArrayIndex index) const

const ShaderInputImageUnboundedArrayDescriptor &	GetShaderInput (ShaderInputImageUnboundedArrayIndex index) const

AZStd::span< const ShaderInputBufferDescriptor >	GetShaderInputListForBuffers () const

AZStd::span< const ShaderInputImageDescriptor >	GetShaderInputListForImages () const

AZStd::span< const ShaderInputSamplerDescriptor >	GetShaderInputListForSamplers () const

AZStd::span< const ShaderInputConstantDescriptor >	GetShaderInputListForConstants () const

AZStd::span< const ShaderInputBufferUnboundedArrayDescriptor >	GetShaderInputListForBufferUnboundedArrays () const

AZStd::span< const ShaderInputImageUnboundedArrayDescriptor >	GetShaderInputListForImageUnboundedArrays () const

Interval	GetGroupInterval (ShaderInputBufferIndex inputIndex) const

Interval	GetGroupInterval (ShaderInputImageIndex inputIndex) const

Interval	GetGroupInterval (ShaderInputSamplerIndex inputIndex) const

Interval	GetConstantInterval (ShaderInputConstantIndex inputIndex) const
	The interval of a constant is its byte [min, max) into the constant data.

uint32_t	GetGroupSizeForBuffers () const

uint32_t	GetGroupSizeForImages () const

uint32_t	GetGroupSizeForBufferUnboundedArrays () const

uint32_t	GetGroupSizeForImageUnboundedArrays () const

uint32_t	GetGroupSizeForSamplers () const

uint32_t	GetConstantDataSize () const
	Constants are different and live in an opaque buffer of bytes instead of a resource group.

uint32_t	GetBindingSlot () const

uint32_t	GetShaderVariantKeyFallbackSize () const
	Returns the ShaderVariantKey fallback size in bits, or 0 if this SRG can't handle that function.

bool	HasShaderVariantKeyFallbackEntry () const
	Returns true if the ShaderResourceGroup has been designated as a ShaderVariantKey fallback.

const RHI::ShaderInputConstantIndex &	GetShaderVariantKeyFallbackConstantIndex () const
	Returns the ShaderVariantKey fallback index, or invalid index if this SRG is not designated as fallback.

HashValue64	GetHash () const
	Returns the hash computed in Finalize.

const ConstantsLayout *	GetConstantsLayout () const
	Returns the constants data layout;.

bool	ValidateAccess (RHI::ShaderInputConstantIndex inputIndex) const

bool	ValidateAccess (RHI::ShaderInputBufferIndex inputIndex, uint32_t arrayIndex) const

bool	ValidateAccess (RHI::ShaderInputImageIndex inputIndex, uint32_t arrayIndex) const

bool	ValidateAccess (RHI::ShaderInputSamplerIndex inputIndex, uint32_t arrayIndex) const

bool	ValidateAccess (RHI::ShaderInputBufferUnboundedArrayIndex inputIndex) const

bool	ValidateAccess (RHI::ShaderInputImageUnboundedArrayIndex inputIndex) const

Static Public Member Functions
static void	Reflect (ReflectContext *context)

static Ptr< ShaderResourceGroupLayout >	Create ()

Friends
template<typename , typename >
struct	AnyTypeInfoConcept

template<typename , bool , bool >
struct	Serialize::InstanceFactory

Detailed Description

ShaderResourceGroupLayout defines a set of valid shader inputs to a ShaderResourceGroup.

Each 'shader input' adheres to the following type:

Buffer (Constant, Read, Read-Write).
Image (Read, Read-Write)
Sampler
Constant

Buffers, images, and samplers are collectively called 'resources'. These three types form disjoint groups. Each resource shader input has an array of resources. These arrays are flattened into a 'resource group' for each resource type. For example, if a buffer input at index '0' has two elements, and the buffer input at index '1' has three, the "buffer shader resource group" forms a list of five elements.

Each shader input maps to a named definition in a shader source file. This name is retained in order to support a basic name-to-index reflection API.

Constant shader inputs are treated a bit differently. Each constant input spans a range of bytes in an implicit constant buffer.

To use the class, assign shader inputs using AddShaderInput, and call Finalize to complete construction of the layout. This class is intended to be built using an offline shader compiler, and serialized to / from disk.

Member Function Documentation

◆ AddShaderInput()

void AZ::RHI::ShaderResourceGroupLayout::AddShaderInput ( const ShaderInputBufferDescriptor & buffer )

Adds a shader input to the shader resource group layout. The layout maintains a separate list for each type of shader input. Order in each list is preserved.

◆ AddStaticSampler()

void AZ::RHI::ShaderResourceGroupLayout::AddStaticSampler ( const ShaderInputStaticSamplerDescriptor & sampler )

Adds a static sampler to the layout. Static samplers are immutable and cannot be assigned at runtime.

◆ Finalize()

bool AZ::RHI::ShaderResourceGroupLayout::Finalize ( )

Finalizes the layout for access. Must be called prior to usage or serialization. It is not permitted to mutate the layout once Finalize is called. Clear must be called first. If the call fails, the layout is cleared back to an empty state and false is returned. Otherwise, true is returned and the layout is considered finalized.

◆ FindShaderInputBufferIndex()

ShaderInputBufferIndex AZ::RHI::ShaderResourceGroupLayout::FindShaderInputBufferIndex ( const Name & name ) const

Resolves an shader input name to an index for each type of shader input. To maximize performance, the name to index resolve should be done as an initialization step and the indices cached.

◆ GetBindingSlot()

uint32_t AZ::RHI::ShaderResourceGroupLayout::GetBindingSlot ( ) const

Returns the binding slot allocated to this layout. Each layout occupies a logical binding slot on a command list. All shader resource groups which use the layout are bound to that slot.

◆ GetGroupInterval()

Interval AZ::RHI::ShaderResourceGroupLayout::GetGroupInterval ( ShaderInputBufferIndex inputIndex ) const

Each shader input may contain multiple shader resources. The layout computes a separate shader resource group for each resource type. For example, given shader inputs 'A', 'B' and 'C':

Shader Input List: (A) (B) (C) Shader Resource Group: [0, 1, 2] [3, 4] [5]

[A, B, C] form a list of three shader inputs. But the shader resource group forms a group of six resources. The following methods provide a mapping from a shader input index to an interval of resources in the resource group.

The following methods return an interval - [min, max) - into the shader resource group for that resource type.

◆ GetGroupSizeForBuffers()

uint32_t AZ::RHI::ShaderResourceGroupLayout::GetGroupSizeForBuffers ( ) const

Returns the total size of the flat resource table for each type of resource. Note that this size is not 1-to-1 with the 'shader input list' for that type of resource, since a shader input may be an array of resources.

NOTE: The resource table maps to the following types per resource:

◆ GetShaderInput()

const ShaderInputBufferDescriptor & AZ::RHI::ShaderResourceGroupLayout::GetShaderInput ( ShaderInputBufferIndex index ) const

Returns the shader input associated with the requested index. It is not permitted to call this method with a null index. An assert will fire otherwise.

◆ GetShaderInputListForBuffers()

AZStd::span< const ShaderInputBufferDescriptor > AZ::RHI::ShaderResourceGroupLayout::GetShaderInputListForBuffers ( ) const

Returns the full lists of each kind of shader input added to the layout. Inputs maintain their original order with respect to AddShaderInput. Each type of shader input has its own separate list.

◆ GetUniqueId()

const AZStd::string & AZ::RHI::ShaderResourceGroupLayout::GetUniqueId ( ) const

inline

This string will be used at runtime for both ShaderResourceGroup and ShaderResourceGroupPool to create a unique InstanceId to avoid redundant copies in memory.

◆ SetBindingSlot()

void AZ::RHI::ShaderResourceGroupLayout::SetBindingSlot ( uint32_t bindingSlot )

Assigns the shader resource group binding slot to the layout. The binding slot is defined by the shader content and dictates which logical slot to use when binding shader resource groups to command lists.

◆ SetShaderVariantKeyFallback()

void AZ::RHI::ShaderResourceGroupLayout::SetShaderVariantKeyFallback	(	const Name &	shaderConstantName,
		uint32_t	bitSize
	)

Designates this SRG as ShaderVariantKey fallback by providing the generated shader constant name and its length in bits.

◆ SetUniqueId()

void AZ::RHI::ShaderResourceGroupLayout::SetUniqueId ( const AZStd::string & uniqueId )

inline

The Set function as described above. It is usually the Source azsl/azsli/srgi file where this SRG comes from.

◆ ValidateAccess() [1/3]

bool AZ::RHI::ShaderResourceGroupLayout::ValidateAccess	(	RHI::ShaderInputBufferIndex	inputIndex,
		uint32_t	arrayIndex
	)		const

Validates that the inputIndex is valid and the arrayIndex is less than the total array size of the shader input. Emits an assert and returns false on failure; returns true on success. If validation is disabled true is always returned.

◆ ValidateAccess() [2/3]

bool AZ::RHI::ShaderResourceGroupLayout::ValidateAccess ( RHI::ShaderInputBufferUnboundedArrayIndex inputIndex ) const

Validates that the inputIndex is valid. Emits an assert and returns false on failure; returns true on success. If validation is disabled true is always returned.

◆ ValidateAccess() [3/3]

bool AZ::RHI::ShaderResourceGroupLayout::ValidateAccess ( RHI::ShaderInputConstantIndex inputIndex ) const