MRenderOverride Class Reference

This reference page is linked to from the following overview topics: Extension for Autodesk Maya 2013, Rendering Overrides, Transition Guide, Devkit Samples, 3.6 Render Loop Overrides.

---

Search for all occurrences

---

Detailed Description

Base class for defining a rendering override.

#include <MViewport2Renderer.h>

List of all members.

Public Member Functions
	MRenderOverride (const MString &name)
	Constructor for a name render override.
virtual	~MRenderOverride ()
	Default destructor for a render override.
virtual MHWRender::DrawAPI	supportedDrawAPIs () const
	Returns the draw API supported by this override.
virtual bool	startOperationIterator ()=0
	In order for an override to indicate the set of operations that are to be performed it must implement overrides for the iterator methods on the override: startOperationIterator() renderOperation() nextRenderOperation()
virtual MRenderOperation *	renderOperation ()=0
	Return the current operation being iterated over.
virtual bool	nextRenderOperation ()=0
	Iterate to the next operation.
const MString &	name () const
	Query the name of the override.
virtual MString	uiName () const
	Query the user interface name for the override.
virtual MStatus	setup (const MString &destination)
	Perform any setup required before render operations are to be executed.
virtual MStatus	cleanup ()
	Perform any cleanup required following the execution of render operations.
Friends
class	M3dView Search for all occurrences

---

Constructor & Destructor Documentation

MRenderOverride

(

const MString &

name

)

Constructor for a name render override.

Parameters:

[in]

name

Name of render override

---

Member Function Documentation

MHWRender::DrawAPI supportedDrawAPIs

(

)

const [virtual]

Search for all occurrences

Returns the draw API supported by this override.

The returned value may be formed as the bitwise 'or' of MRenderer::DrawAPI elements to indicate that the override supports multiple draw APIs. This method returns 'MHWRender::kOpenGL' by default.

Returns:

The draw API supported by this override

bool startOperationIterator

(

)

[pure virtual]

Search for all occurrences

In order for an override to indicate the set of operations that are to be performed it must implement overrides for the iterator methods on the override:

• startOperationIterator()
• renderOperation()
• nextRenderOperation()

The order that the operations are returned via these methods determines the order that the operations are invoked.

If there is a user operation (MUserRenderOperation) the execute() method for that operation will be called when the operation is invoked.

Note that the ordering will not change during one invocation of an override which is delimited by the setup() and cleanup() calls.

This particular method is called to allow the override to start iterating over a list of operations to be performed by the override.

The operations that are returned can be thought of as representing a "command list". This command list will perform in order from start to end.

Pseudo-code for the internal Maya iteration logic would look something like this:

	MRenderOverride override;
	if (override.startOperationIterator())
	{
		--> Get operation
		MRenderOperation *op = override.renderOperation();
		while (op)
		{
			if (op)
				--> Add to "list" of operations to perform

			--> Iterate to next operation
			op = override.nextRenderOperation();
		}
	}
	

Returns:

True if there are any operations to iterate over. Note that an override with no operations will basically mean that the override draws nothing. In this case the renderer will perform it's default rendering operations.

MRenderOperation * renderOperation

(

)

[pure virtual]

Search for all occurrences

Return the current operation being iterated over.

The call to currentOperation() will occur after a startIteratingOperations() call.

Returns:

Reference to the current operation

bool nextRenderOperation

(

)

[pure virtual]

Search for all occurrences

Iterate to the next operation.

If there are no more operations then this method should return false.

Returns:

True if there is a subsequent operation.

const MString & name

(

)

const

Search for all occurrences

Query the name of the override.

Returns:

Name of the override

MString uiName

(

)

const [virtual]

Search for all occurrences

Query the user interface name for the override.

If an empty string is returned then the value returned from the name() method will be used as the user interface name.

Returns:

UI name. The default implementation returns an empty string.

MStatus setup

(

const MString &

destination

)

[virtual]

Search for all occurrences

Perform any setup required before render operations are to be executed.

The default behaviour performs no actions.

An override is called once per render. The order of method calls when an override is called is as follows:

• setup()
• startOperationIterator()
  • renderOperation()
  • nextRenderOperation() until no more operations
• cleanup()

Parameters:

[in]

destination

String identifier which gives an indication as to where this override is being applied. Presently this will return a viewport panel name for interactive rendering.

Returns:

Status code. MStatus::kSuccess is returned by default.

Status Codes:

• MStatus::kSuccess Method succeed.
• MStatus::kFailure Method failed.

MStatus cleanup

(

)

[virtual]

Search for all occurrences

Perform any cleanup required following the execution of render operations.

The default behaviour performs no actions.

Returns:

Status code. MStatus::kSuccess is returned by default.

Status Codes:

• MStatus::kSuccess Method succeed.
• MStatus::kFailure Method failed.