ID3D11DeviceContext::SetPredication Method

Set a rendering predicate.

Syntax

public:
void SetPredication(
         ID3D11Predicate *pPredicate,
         BOOL PredicateValue
)  

Parameters

pPredicate
Type: ID3D11Predicate *

[in, optional] Pointer to a predicate (see ID3D11Predicate). A NULL value indicates “no” predication; in this case, the value of PredicateValue is irrelevant but will be preserved for ID3D11DeviceContext::GetPredication.

PredicateValue
Type: BOOL 

[in] If TRUE, rendering will be affected by when the predicate’s conditions are met. If FALSE, rendering will be affected when the conditions are not met.

Return value

None.

Remarks

The predicate must be in the “issued” or “signaled” state to be used for predication. While the predicate is set for predication, calls to ID3D11DeviceContext::Begin and ID3D11DeviceContext::End are invalid.

This method is used to denote that subsequent rendering and resource manipulation commands are not actually performed if the resulting Predicate data of the Predicate is equal to the PredicateValue. However, some Predicates are only hints, so they may not actually prevent operations from being performed.

The primary usefulness of Predication is to allow an application to issue graphics commands without taking the performance hit of spinning, waiting for ID3D11DeviceContext::GetData to return. So, Predication can occur while ID3D11DeviceContext::GetData returns S_FALSE. Another way to think of it: an application can also use Predication as a fallback, if it is possible that ID3D11DeviceContext::GetData returns S_FALSE. If ID3D11DeviceContext::GetData returns S_OK, the application can skip calling the graphics commands manually with it’s own application logic.

Requirements

Header: Declared in d3d11_x.h (d3d11.h on other Windows platforms).

Library: Use d3d11_x.lib (d3d11.lib on other Windows platforms).

See also

ID3D11DeviceContext

ID3D11DeviceContext Members