DirectX SDK

IDirectDrawGammaControl

Applications use the methods of the IDirectDrawGammaControl interface to adjust the red, green, and blue gamma ramp levels of the primary surface. This section is a reference to the methods of this interface. This interface is supported by DirectDrawSurface objects; you can retrieve a pointer to this interface by calling the IUnknown::QueryInterface method of a DirectDrawSurface object, specifying the IID_IDirectDrawGammaControl reference identifier.

For a conceptual overview, see Gamma and Color Controls.

The interface has the following methods:

Gamma ramps GetGammaRamp
  SetGammaRamp

The IDirectDrawGammaControl interface, like all COM interfaces, inherits the IUnknown interface methods. The IUnknown interface supports the following three methods:

IUnknown AddRef
  QueryInterface
Release

You can use the LPDIRECTDRAWGAMMACONTROL data type to declare a variable that contains a pointer to an IDirectDrawGammaControl interface. The Ddraw.h header file declares the data type with the following code:

typedef struct IDirectDrawGammaControl    FAR *LPDIRECTDRAWGAMMACONTROL;

Requirements

  Windows NT/2000: Requires Windows 2000.
  Windows 95/98: Requires Windows 95 or later. Available as a redistributable for Windows 95.
  Header: Declared in ddraw.h.
  Import Library: Use ddraw.lib.