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SetViewportExtEx function

The SetViewportExtEx function sets the horizontal and vertical extents of the viewport for a device context by using the specified values.

Syntax

Copy

BOOL SetViewportExtEx(
  __in   HDC hdc,
  __in   int nXExtent,
  __in   int nYExtent,
  __out  LPSIZE lpSize
);

Parameters

hdc [in]: A handle to the device context.
nXExtent [in]: The horizontal extent, in device units, of the viewport.
nYExtent [in]: The vertical extent, in device units, of the viewport.
lpSize [out]: A pointer to a SIZE structure that receives the previous viewport extents, in device units. If lpSize is NULL, this parameter is not used.

Return value

If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero.

Remarks

The viewport refers to the device coordinate system of the device space. The extent is the maximum value of an axis. This function sets the maximum values for the horizontal and vertical axes of the viewport in device coordinates (or pixels). When mapping between page space and device space, SetWindowExtEx and SetViewportExtEx determine the scaling factor between the window and the viewport. For more information, see Transformation of Coordinate Spaces.

When the following mapping modes are set, calls to the SetWindowExtEx and SetViewportExtEx functions are ignored.

MM_HIENGLISH
MM_HIMETRIC
MM_LOENGLISH
MM_LOMETRIC
MM_TEXT
MM_TWIPS

When MM_ISOTROPIC mode is set, an application must call the SetWindowExtEx function before it calls SetViewportExtEx. Note that for the MM_ISOTROPIC mode certain portions of a nonsquare screen may not be available for display because the logical units on both axes represent equal physical distances.

Examples

For an example, see Invalidating the Client Area.

Requirements

Minimum supported client	Windows 2000 Professional
Minimum supported server	Windows 2000 Server
Header	Wingdi.h (include Windows.h)
Library	Gdi32.lib
DLL	Gdi32.dll