# Function Reference

# _WinAPI_SetDeviceGammaRamp

Sets the gamma ramp on direct color display boards that support downloadable gamma ramps in hardware

#include <WinAPIGdi.au3>
_WinAPI_SetDeviceGammaRamp ( $hDC, Const ByRef $aRamp )

## Parameters

$hDC | Handle to a device context of the direct color display board in question.
$aRamp | The 2D array ([r1, g1, b1], [r2, g2, b2], ... [r256, g256, b256]) that contains the gamma ramp to be set. Each element in this array is an integer value with a range from 0 to 65535 which is a mapping between RGB values in the frame buffer and digital-analog-converter (DAC) values. The RGB values must be stored in the most significant bits of each WORD to increase DAC independence. (See MSDN for more information)

## Return Value

Success: | True.
Failure: | False.

## Remarks

Direct color display modes do not use color lookup tables and are usually 16, 24, or 32 bit. Not all direct
color video boards support loadable gamma ramps. The _WinAPI_SetDeviceGammaRamp() succeeds only for devices
with drivers that support downloadable gamma ramps in hardware.

## See Also

Search SetDeviceGammaRamp in MSDN Library.