Setup method

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Defines the input and output data objects used in the transform.

Syntax

HRESULT retVal = object.Setup(punkInputs, ulNumInputs, punkOutputs, ulNumOutputs, dwFlags);

Parameters

  • punkInputs [in]
    Type: IUnknown * const

    Pointer to an array of one or more data objects to be used for input.

  • ulNumInputs [in]
    Type: unsigned long

    Number of data object interface pointers in the input array.

  • punkOutputs [in]
    Type: IUnknown * const

    Pointer to an array of one or more data objects where data will be written.

  • ulNumOutputs [in]
    Type: unsigned long

    Number of data object interface pointers in the output array.

  • dwFlags [in]
    Type: DWORD

    Reserved. Must be set to 0.

Remarks

This method is used to perform a required, one-time setup before the IDXTransform::Execute method is used. The correct number of input and output data objects depends on the implementation of the transform. Transitions are usually one-in/one-out objects, whereas procedural objects have no inputs.

If you use this method, you should try to optimize your code for subsequent calls to IDXTransform::Setup. For example, if a transform is passed a new DXSurface, but the height, width, and pixel format have not changed, it might not be necessary to execute all portions of the Setup method again.

To clear a transform, use Setup with the dwFlags parameter equal to zero and the number of inputs and outputs equal to zero. If the punkInputs and the punkOutputs parameters are NULL, and it is a quick setup, the current input and output objects are released. If the transform is used again on data of the same type, you must use Setup again for the transform.

The IDXTransformFactory::InitializeTransform method also uses the Setup method.