IPrintOemUni::DriverDMS method (prcomoem.h)

Artikel
04/01/2021

The IPrintOemUni::DriverDMS method allows a rendering plug-in for Unidrv to indicate that it uses a device-managed drawing surface.

Syntax

HRESULT DriverDMS(
  PVOID  pDevObj,
  PVOID  pBuffer,
  DWORD  cbSize,
  PDWORD pcbNeeded
);

Parameters

pDevObj

Caller-supplied pointer to a DEVOBJ structure.

pBuffer

Caller-supplied pointer to a buffer to receive method-specified flags. (See the following Remarks section.)

cbSize

Caller-supplied size, in bytes, of the buffer pointed to by pBuffer.

pcbNeeded

Caller-supplied pointer to a location to receive the required minimum pBuffer size.

Return value

The method must return one of the following values.

Return code	Description
S_OK	The operation succeeded.
E_FAIL	The operation failed

Remarks

A rendering plug-in for Unidrv must implement the IPrintOemUni::DriverDMS method. The method will be called only if Unidrv finds a valid interface pointer to the OEM's rendering plug-in.

The IPrintOemUni::DriverDMS method allows a rendering plug-in to indicate that it will be using a device-managed drawing surface instead of the default GDI-managed surface.

The method must specify HOOK_-prefixed flags in the buffer pointed to by pBuffer, indicating which of the plug-in's graphics DDI hooking functions are to be called for the drawing surface. The HOOK_-prefixed flags are defined in winddi.h and described in the EngAssociateSurface function's description. Flags specified by IPrintOemUni::DriverDMS are passed by Unidrv to EngAssociateSurface. (Note that to support a device-managed surface, the rendering plug-in must hook out all drawing functions.) For more information, see Handling Device-Managed Surfaces.

If IPrintOemUni::DriverDMS sets flags in the buffer pointed to by pBuffer, Unidrv creates a device-managed surface by calling EngCreateDeviceSurface. If IPrintOemUni::DriverDMS does not set any flags, Unidrv creates a GDI-managed surface by calling EngCreateBitmap. In either of these cases, IPrintOemUni::DriverDMS should return S_OK.

If the output buffer size specified by cbSize is too small, the method should specify the required size in the location pointed to by pcbNeeded, call SetLastError(ERROR_INSUFFICIENT_BUFFER), and return E_FAIL.

Requirements

Requirement	Value
Target Platform	Desktop
Header	prcomoem.h (include Prcomoem.h)

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