MCI_WHERE

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The MCI_WHERE command obtains the clipping rectangle for the video device. Digital-video, and video-overlay devices recognize this command. The top and left members of the returned RECT contain the origin of the clipping rectangle, and the right and bottom members contain the width and height of the clipping rectangle. (This is not the standard use of the right and bottom members.)

To send this command, call the mciSendCommand function with the following parameters.

MCIERROR mciSendCommand(
  MCIDEVICEID wDeviceID, 
  MCI_WHERE, 
  DWORD dwFlags, 
  (DWORD) (LPMCI_GENERIC_PARMS) lpQuery
);

Parameters

wDeviceID

Device identifier of the MCI device that is to receive the command message.

dwFlags

MCI_NOTIFY, MCI_WAIT, or, for digital-video devices, MCI_TEST. For information about these flags, see The Wait, Notify, and Test Flags.

lpQuery

Pointer to an MCI_GENERIC_PARMS structure. (Devices with extended command sets might replace this structure with a device-specific structure.)

Return Values

Returns zero if successful or an error otherwise.

Remarks

The following additional flags are used with the digitalvideo device type:

MCI_DGV_WHERE_DESTINATION

Obtains a description of the rectangular region used to display video and images in the client area of the current window.

MCI_DGV_WHERE_FRAME

Obtains a description of the rectangular region of the frame buffer into which images from the video rectangle are scaled. The rectangle coordinates are placed in the rc member of the structure identified by lpQuery.

MCI_DGV_WHERE_MAX

When used with MCI_DGV_WHERE_DESTINATION or MCI_DGV_WHERE_SOURCE, the rectangle returned indicates the maximum width and height of the specified region. When used with MCI_DGV_WHERE_WINDOW, the rectangle returned indicates the size of the entire display.

MCI_DGV_WHERE_SOURCE

Obtains a description of the rectangular region (cropped from the frame buffer) that is stretched to fit the destination rectangle on the display.

MCI_DGV_WHERE_VIDEO

Obtains a description of the rectangular region cropped from the presentation source to fill the frame rectangle in the frame buffer. The rectangle coordinates are placed in the rc member of the structure identified by lpQuery.

MCI_DGV_WHERE_WINDOW

Obtains a description of the display-window frame.

For digital-video devices, the lpQuery parameter points to an MCI_DGV_WHERE_PARMS structure. The MCI_DGV_WHERE_PARMS structure is identical to the MCI_DGV_RECT_PARMS structure.

The following additional flags are used with the overlay device type:

MCI_OVLY_WHERE_DESTINATION

Obtains the destination display rectangle. The rectangle coordinates are placed in the rc member of the structure identified by lpQuery.

MCI_OVLY_WHERE_FRAME

Obtains the overlay frame rectangle. The rectangle coordinates are placed in the rc member of the structure identified by lpQuery.

MCI_OVLY_WHERE_SOURCE

Obtains the source rectangle. The rectangle coordinates are placed in the rc member of the structure identified by lpQuery.

MCI_OVLY_WHERE_VIDEO

Obtains the video rectangle. The rectangle coordinates are placed in the rc member of the structure identified by lpQuery.

For video-overlay devices, the lpQuery parameter points to an MCI_OVLY_RECT_PARMS structure.

Requirements

**  Windows NT/2000/XP:** Included in Windows NT 3.1 and later.
**  Windows 95/98/Me:** Included in Windows 95 and later.
**  Header:** Declared in Mmsystem.h; include Windows.h.

See Also

MCI, MCI Commands, MCI_DGV_RECT_PARMS, MCI_GENERIC_PARMS, MCI_OVLY_RECT_PARMS