Open 3D Engine Atom Gem API Reference 23.10.0
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Public Member Functions | List of all members
AZ::RHI::ConstantsData Class Reference

#include <ConstantsData.h>

Public Member Functions

 ConstantsData (const ConstantsLayout *layout)
 
 AZ_DEFAULT_COPY_MOVE (ConstantsData)
 
bool SetConstantRaw (ShaderInputConstantIndex inputIndex, const void *bytes, size_t byteCount)
 Assigns constant data for the given constant shader input index.
 
bool SetConstantRaw (ShaderInputConstantIndex inputIndex, const void *bytes, size_t byteOffset, size_t byteCount)
 
template<typename T >
bool SetConstant (ShaderInputConstantIndex inputIndex, const T &value)
 Assigns a value of type T to the constant shader input.
 
bool SetConstantMatrixRows (ShaderInputConstantIndex inputIndex, const Matrix3x3 &value, uint32_t rowCount)
 Assigns a specified number of rows from a Matrix.
 
bool SetConstantMatrixRows (ShaderInputConstantIndex inputIndex, const Matrix3x4 &value, uint32_t rowCount)
 
bool SetConstantMatrixRows (ShaderInputConstantIndex inputIndex, const Matrix4x4 &value, uint32_t rowCount)
 
template<typename T >
bool SetConstant (ShaderInputConstantIndex inputIndex, const T &value, uint32_t arrayIndex)
 Assigns a value of type T to the constant shader input, at an array offset.
 
template<typename T >
bool SetConstantArray (ShaderInputConstantIndex inputIndex, AZStd::span< const T > values)
 Assigns an array of type T to the constant shader input.
 
bool SetConstantData (const void *bytes, size_t byteCount)
 Assigns constant data as a whole.
 
bool SetConstantData (const void *bytes, size_t byteOffset, size_t byteCount)
 
template<typename T >
AZStd::span< const T > GetConstantArray (ShaderInputConstantIndex inputIndex) const
 
template<typename T >
T GetConstant (ShaderInputConstantIndex inputIndex) const
 
template<typename T >
T GetConstant (ShaderInputConstantIndex inputIndex, uint32_t arrayIndex) const
 
AZStd::span< const uint8_t > GetConstantRaw (ShaderInputConstantIndex inputIndex) const
 Returns constant data for the given shader input index as a span of bytes.
 
AZStd::span< const uint8_t > GetConstantData () const
 Returns the opaque constant data populated by calls to SetConstant and SetConstantData.
 
const ConstantsLayout * GetLayout () const
 Returns the constants layout.
 
bool ConstantIsEqual (const ConstantsData &other, ShaderInputConstantIndex inputIndex) const
 Returns whether other constant data and this have the same value at the specified shader input index.
 
AZStd::vector< ShaderInputConstantIndex > GetIndicesOfDifferingConstants (const ConstantsData &other) const
 
template<>
bool SetConstant (ShaderInputConstantIndex inputIndex, const bool &value)
 
template<>
bool SetConstant (ShaderInputConstantIndex inputIndex, const Matrix3x3 &value)
 
template<>
bool SetConstant (ShaderInputConstantIndex inputIndex, const Matrix3x4 &value)
 
template<>
bool SetConstant (ShaderInputConstantIndex inputIndex, const Matrix4x4 &value)
 
template<>
bool SetConstant (ShaderInputConstantIndex inputIndex, const Vector2 &value)
 
template<>
bool SetConstant (ShaderInputConstantIndex inputIndex, const Vector3 &value)
 
template<>
bool SetConstant (ShaderInputConstantIndex inputIndex, const Vector4 &value)
 
template<>
bool SetConstant (ShaderInputConstantIndex inputIndex, const Color &value)
 
template<>
bool SetConstantArray (ShaderInputConstantIndex inputIndex, AZStd::span< const bool > values)
 
template<>
bool GetConstant (ShaderInputConstantIndex inputIndex) const
 
template<>
Matrix3x3 GetConstant (ShaderInputConstantIndex inputIndex) const
 
template<>
Matrix3x4 GetConstant (ShaderInputConstantIndex inputIndex) const
 
template<>
Matrix4x4 GetConstant (ShaderInputConstantIndex inputIndex) const
 
template<>
Vector2 GetConstant (ShaderInputConstantIndex inputIndex) const
 
template<>
Vector3 GetConstant (ShaderInputConstantIndex inputIndex) const
 
template<>
Vector4 GetConstant (ShaderInputConstantIndex inputIndex) const
 
template<>
Color GetConstant (ShaderInputConstantIndex inputIndex) const
 

Detailed Description

The intent of this class is to provide fast and thin access to the underlying constant data (inline or from an SRG), with basic validation to protect the user. As a secondary objective, it provides type-specific convenience operations as long as they don't violate the primary "fast" and "thin" objectives. To clarify, thin means we don't make assumptions about the data or how the user wants to operate on the data, and the convenience operations boil down to thin wrappers for single calls to SetConstantRaw and GetConstantRaw. So these convenience functions are provided in situations that are "low-hanging-fruit".

Member Function Documentation

◆ GetConstant() [1/2]

template<typename T >
T AZ::RHI::ConstantsData::GetConstant ( ShaderInputConstantIndex  inputIndex) const

Returns the constant data as type 'T' returned by value. The size of the constant region must match the size of T exactly. Otherwise, an empty instance is returned.

◆ GetConstant() [2/2]

template<typename T >
T AZ::RHI::ConstantsData::GetConstant ( ShaderInputConstantIndex  inputIndex,
uint32_t  arrayIndex 
) const

Treats the constant input as an array of type T, returning the element by value at the specified array index. The size of the constant region must equally partition into an array of type T. Otherwise, an empty instance is returned.

◆ GetConstantArray()

template<typename T >
AZStd::span< const T > AZ::RHI::ConstantsData::GetConstantArray ( ShaderInputConstantIndex  inputIndex) const

Returns constant data for the given shader input index as a template type. The stride of T must match the size of the constant input region. The number of elements in the returned array is the number of evenly divisible elements. If the strides do not match, an empty array is returned.

◆ GetIndicesOfDifferingConstants()

AZStd::vector< ShaderInputConstantIndex > AZ::RHI::ConstantsData::GetIndicesOfDifferingConstants ( const ConstantsData &  other) const

Performs a diff between this and input constant data and returns a list of all the shader input indices for which the constants are not the same between the two. If one of the two has more constants than the other, these additional constants will be added to the end of the returned list.

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