MUniformParameter Class Reference
[OpenMayaRender - API module for rendering]

#include <MUniformParameter.h>

List of all members.

---

Detailed Description

Uniform parameter.

The MUniformParameter class provides a high-level interface to hardware shader uniform parameters. By defining your shader's uniform parameters through this class, you allow Maya to handle the attributes, editing, serialisation, and caching for you in a standard way that ensure you'll be able to leverage future performance and functionlity improvements.

At setup time (either initial load or when the effect/technique is changed), your shader simply creates the list of parameters it requires, specifying the name, type, semantic of the parameters. At render time, you can then use the parameters to directly access the appropriate buffers for that surface data.

If you include a custom Attribute Editor template for your shader node, you can include these surface parameters by calling the AEhwUniformTemplateParameters script function. The following sample code provides a basic template you can modify - however your AE template can use as much or as little of this as you like:

global int $yourUniformNameTemplateInitialised = 0;

global proc AEyourUniformNameTemplate ( string $node )
{
        global int $yourUniformNameTemplateInitialised;
        if( $yourUniformNameTemplateInitialised == 0)
        {
                source "AEhwUniformTemplate.mel";
                $yourUniformNameTemplateInitialised = 1;
        }

        AEhwUniformTemplateHeader( $node);

        // Insert custom attributes between the swatch and the parameters here

        AEhwUniformTemplateParameters( $node);

        // Insert custom attributes after the parameters here

        AEhwUniformTemplateFooter( $node);
}

Examples:

hlslShader.cpp.

Public Types
enum	DataType {    kTypeUnknown, kTypeBool, kTypeInt, kTypeFloat,    kType1DTexture, kType2DTexture, kType3DTexture, kTypeCubeTexture,    kTypeEnvTexture, kTypeString }
	Parameter data types. More...
enum	DataSemantic {    kSemanticUnknown, kSemanticObjectDir, kSemanticWorldDir, kSemanticViewDir,    kSemanticProjectionDir, kSemanticObjectPos, kSemanticWorldPos, kSemanticViewPos,    kSemanticProjectionPos, kSemanticColor, kSemanticNormal, kSemanticBump,    kSemanticEnvironment, kSemanticWorldMatrix, kSemanticWorldInverseMatrix, kSemanticWorldInverseTransposeMatrix,    kSemanticViewMatrix, kSemanticViewInverseMatrix, kSemanticViewInverseTransposeMatrix, kSemanticProjectionMatrix,    kSemanticProjectionInverseMatrix, kSemanticProjectionInverseTransposeMatrix, kSemanticWorldViewMatrix, kSemanticWorldViewInverseMatrix,    kSemanticWorldViewInverseTransposeMatrix, kSemanticWorldViewProjectionMatrix, kSemanticWorldViewProjectionInverseMatrix, kSemanticWorldViewProjectionInverseTransposeMatrix,    kSemanticColorTexture, kSemanticNormalTexture, kSemanticBumpTexture, kSemanticNormalizationTexture,    kSemanticTime }
	Parameter semantics (i.e. what the parameter represents). More...
Public Member Functions
	MUniformParameter ()
	MUniformParameter (const MString &name, DataType type, DataSemantic semantic, unsigned int numRows=1, unsigned int numColumns=1, void *userData=NULL)
	~MUniformParameter ()
const MUniformParameter &	operator= (const MUniformParameter &other)
const MString &	name () const
MUniformParameter::DataType	type () const
MUniformParameter::DataSemantic	semantic () const
unsigned int	numRows () const
unsigned int	numColumns () const
unsigned int	numElements () const
void *	userData () const
bool	isATexture () const
bool	hasChanged (const MGeometryList &iterator) const
const float *	getAsFloatArray (const MGeometryList &iterator) const
void	setAsFloatArray (const float *value, unsigned int maxElements) const
float	getAsFloat (const MGeometryList &iterator) const
void	setAsFloat (float value) const
MString	getAsString (const MGeometryList &iterator) const
void	setAsString (const MString &value) const
bool	getAsBool (const MGeometryList &iterator) const
void	setAsBool (bool value) const
int	getAsInt (const MGeometryList &iterator) const
void	setAsInt (int value) const
MPlug	getSource () const
void	setDirty ()
Friends
class	MUniformParameterList

---

Member Enumeration Documentation

enum MUniformParameter::DataType

Parameter data types.

Enumerator:

kTypeUnknown
kTypeBool
kTypeInt
kTypeFloat
kType1DTexture
kType2DTexture
kType3DTexture
kTypeCubeTexture
kTypeEnvTexture
kTypeString

enum MUniformParameter::DataSemantic

Parameter semantics (i.e. what the parameter represents).

Enumerator:

kSemanticUnknown
kSemanticObjectDir
kSemanticWorldDir
kSemanticViewDir
kSemanticProjectionDir
kSemanticObjectPos
kSemanticWorldPos
kSemanticViewPos
kSemanticProjectionPos
kSemanticColor
kSemanticNormal
kSemanticBump
kSemanticEnvironment
kSemanticWorldMatrix
kSemanticWorldInverseMatrix
kSemanticWorldInverseTransposeMatrix
kSemanticViewMatrix
kSemanticViewInverseMatrix
kSemanticViewInverseTransposeMatrix
kSemanticProjectionMatrix
kSemanticProjectionInverseMatrix
kSemanticProjectionInverseTransposeMatrix
kSemanticWorldViewMatrix
kSemanticWorldViewInverseMatrix
kSemanticWorldViewInverseTransposeMatrix
kSemanticWorldViewProjectionMatrix
kSemanticWorldViewProjectionInverseMatrix
kSemanticWorldViewProjectionInverseTransposeMatrix
kSemanticColorTexture
kSemanticNormalTexture
kSemanticBumpTexture
kSemanticNormalizationTexture
kSemanticTime

---

Constructor & Destructor Documentation

MUniformParameter::MUniformParameter

(

)

Create an uninitialised (i.e. NULL) uniform parameter.

MUniformParameter::MUniformParameter	(	const MString &	name,
		DataType	type,
		DataSemantic	semantic,
		unsigned int	numRows = 1,
		unsigned int	numColumns = 1,
		void *	userData = NULL
	)

Create a new uniform parameter.

Parameters:

[in]	name	the name of the new parameter. For independently configurable inputs, this must be unique across all parameters on the shader. If multiple parameters share the same name, only a single input will be presented to the user, and the value used to populate the set of commonly named parameters.
[in]	type	the type of the new parameter. This can either be an atomic type (e.g. float), or a structure containing other parameters. Vectors of atomic types (e.g. float4) are defined by setting the atomic type to kFloat, and specifying the maxElements value of 4.
[in]	semantic	specifies the expected usage of the paramter (e.g. we expect this to be a colour, or a tangent, etc). This gives Maya a hint as to how the input should be presented to the user, and possibly even which input data is valid for this parameter. This value is ignored for structures.
[in]	numRows	specifies the number of row of the specified type to include (e.g. a vector would have 3 floats)
[in]	numColumns	specifies the number of columns of the specified type to include (e.g. a matrix would have 4 rows and 4 columns of floats)
[in]	userData	opaque data your plugin can use to store the relationship between this parameter and your shader (e.g. a parameter handle)

MUniformParameter::~MUniformParameter

(

)

Class destructor.

---

Member Function Documentation

const MUniformParameter & MUniformParameter::operator=

(

const MUniformParameter &

src

)

Assignment operator

const MString & MUniformParameter::name

(

)

const

Get the name of this parameter

Returns:

The name of this parameter

Examples:

hlslShader.cpp.

MUniformParameter::DataType MUniformParameter::type

(

)

const

Get the type of this parameter

Returns:

The type of this parameter

Examples:

hlslShader.cpp.

MUniformParameter::DataSemantic MUniformParameter::semantic

(

)

const

Get the semantic of this parameter

Returns:

The semantic of this parameter

unsigned int MUniformParameter::numRows

(

)

const

Get the number of rows in this parameter

Returns:

The number of rows in this parameter

unsigned int MUniformParameter::numColumns

(

)

const

Get the number of columns in this parameter

Returns:

The number of columns in this parameter

unsigned int MUniformParameter::numElements

(

)

const

Get the number of elements in this parameter (including rows and columns)

Returns:

The number of elements in this parameter

Examples:

hlslShader.cpp.

void * MUniformParameter::userData

(

)

const

Get the user data for this parameter. User data can be used to store plugin specific information that you want to associate with this parameter. Typically this will be used to store a handle to the effect parameter.

Returns:

The user data for this parameter

Examples:

hlslShader.cpp.

bool MUniformParameter::isATexture

(

)

const

Test if this parameter stores a texture.

Returns:

true if this parameter represents a texture, false otherwise.

Examples:

hlslShader.cpp.

bool MUniformParameter::hasChanged

(

const MGeometryList &

iterator

)

const

Has the value of this parameter changed since the last time it was accessed? This allow your shader to minimise state changes by only updating modified parameters.

Parameters:

[in]

iterator

the current shape being rendered.

Returns:

true if this parameter's value has changed since the last time its value was accessed. false otherwise.

Examples:

hlslShader.cpp.

const float * MUniformParameter::getAsFloatArray

(

const MGeometryList &

iterator

)

const

Get the value of this uniform parameter as one or more floating point values. Because some parameters can be shape-dependent, the method requires access to the current geometry item being rendered.

Parameters:

[in]

iterator

the current shape being rendered.

Returns:

The current floating point value of this uniform parameter.

Examples:

hlslShader.cpp.

void MUniformParameter::setAsFloatArray	(	const float *	value,
		unsigned int	maxElements
	)			const

Set the value of this uniform parameter as one or more floating point values. Note that it is not possible to set shape-specific parameters.

Parameters:

[in]	value	a pointer an array of floats holding the new floating point value(s) for this parameter.
[in]	maxElements	the maximum number of elements in the value array.

Examples:

hlslShader.cpp.

float MUniformParameter::getAsFloat

(

const MGeometryList &

iterator

)

const

Get the value of this uniform parameter as a float. Because some parameters can be shape-dependent, the method requires access to the current geometry item being rendered.

Parameters:

[in]

iterator

the current shape being rendered.

Returns:

The current float value of this uniform parameter.

void MUniformParameter::setAsFloat

(

float

value

)

const

Set the value of this uniform parameter as a float. Note that it is not possible to set shape-dependent parameters.

Parameters:

[in]

value

the new float value for this parameter.

MString MUniformParameter::getAsString

(

const MGeometryList &

iterator

)

const

Get the value of this uniform parameter as a string. Because some parameters can be shape-dependent, the method requires access to the current geometry item being rendered.

Parameters:

[in]

iterator

the current shape being rendered.

Returns:

The current string value of this uniform parameter.

Examples:

hlslShader.cpp.

void MUniformParameter::setAsString

(

const MString &

value

)

const

Set the value of this uniform parameter as a string. Note that it is not possible to set shape-dependent parameters.

Parameters:

[in]

value

the new string value for this parameter.

Examples:

hlslShader.cpp.

bool MUniformParameter::getAsBool

(

const MGeometryList &

iterator

)

const

Get the value of this uniform parameter as a boolean value. Because some parameters can be shape-dependent, the method requires access to the current geometry item being rendered.

Parameters:

[in]

iterator

the current shape being rendered.

Returns:

The current boolean value of this uniform parameter.

Examples:

hlslShader.cpp.

void MUniformParameter::setAsBool

(

bool

value

)

const

Set the value of this uniform parameter as a boolean value. Note that it is not possible to set shape-dependent parameters.

Parameters:

[in]

value

the new value for this parameter.

Examples:

hlslShader.cpp.

int MUniformParameter::getAsInt

(

const MGeometryList &

iterator

)

const

Get the value of this uniform parameter as an integer. Because some parameters can be shape-dependent, the method requires access to the current geometry item being rendered.

Parameters:

[in]

iterator

the current shape being rendered.

Returns:

The current integer value of this uniform parameter.

Examples:

hlslShader.cpp.

void MUniformParameter::setAsInt

(

int

value

)

const

Set the value of this uniform parameter as an integer value. Note that it is not possible to set shape-dependent parameters.

Parameters:

[in]

value

the new value for this parameter.

Examples:

hlslShader.cpp.

MPlug MUniformParameter::getSource

(

)

const

Get the source plug connected to this parameter. Other than textures, this will typically be a NULL plug.

Examples:

hlslShader.cpp.

void MUniformParameter::setDirty

(

)

Mark the data for this parameter as dirty. This will force the parameter to report that it has been changed the next time it is accessed. This allows external events (e.g. device lost, texture management, etc) to force a shader to re-set parameters tied to externally managed resources.

Examples:

hlslShader.cpp.