You can determine whether the hardware supports dynamic gamma ramp adjustment by calling the IDirectDraw7::GetCaps method. After the call, if the DDCAPS2_PRIMARYGAMMA flag is present in the dwCaps2 member of the associate DDCAPS structure, the hardware supports dynamic gamma ramps. DirectDraw does not attempt to emulate this feature, so if the hardware doesn't support it, you can't use it.

You can determine whether the hardware supports dynamic gamma ramp adjustment by calling the DirectDraw7.GetCaps method. After the call, if the DDCAPS2_PRIMARYGAMMA flag is present in the lCaps2 member of the associate DDCAPS type, the hardware supports dynamic gamma ramps. DirectDraw does not attempt to emulate this feature, so if the hardware doesn't support it, you can't use it.