<2> 5/20/99 ggs Added system wide get and restore gamma functions to enable
restoration of original for all devices. Modified functionality
to return pointers vice squirreling away the memory.
<1> 5/20/99 ggs Initial Add
Disclaimer: You may incorporate this sample code into your applications without
restriction, though the sample code has been provided "AS IS" and the
responsibility for its operation is 100% yours. However, what you are
not permitted to do is to redistribute the source as "DSC Sample Code"
after having made changes. If you're going to re-distribute the source,
we require that you make it clear in the source that the code was
descended from Apple Sample Code, but that you've made changes.
*/
// Usage notes:
// SetDeviceGammaRampXX may not return until the VBL following their call, depending on the display driver,
// this is due to the handling of the Control call by the driver.
// Startup and Shutdown:
// GetSystemGammas (...) must be called to save the system gammas prior to using MacGamma
// RestoreSystemGamms (...) must be called before exiting to restore original gamma
// DisposeSystemGammas (...) can then be used to dispose of the system gammas
// Suspend and Resume:
// RestoreSystemGamms (...); DisposeSystemGammas (...); should also be called prior to suspend and
// GetSystemGammas (...) should be called when resuming
// this prevents users from saving display settings with your gammas
// include control --------------------------------------------------
#ifndef MacGamma_h
#define MacGamma_h
// includes ---------------------------------------------------------
#include <Quickdraw.h>
#include <QDOffscreen.h>
// public function declarations -------------------------------------
// 5/20/99: (ggs) added system wide gamma get and restore
Ptr GetSystemGammas (void); // returns a pointer to a set of all current device gammas in native format
// (returns NULL on failure, which means reseting gamma will not be possible)
void RestoreSystemGammas (Ptr pSystemGammas); // restores all system devices to saved gamma setting
void DisposeSystemGammas (Ptr* ppSystemGammas); // iterates through and deletes stored gamma settings
Boolean GetDeviceGammaRampGD (GDHandle hGD, Ptr pRamp); // retrieves the gamma ramp from a graphics device (pRamp: 3 arrays of 256 elements each)
Boolean GetDeviceGammaRampGW (GWorldPtr pGW, Ptr pRamp); // retrieves the gamma ramp from a graphics device associated with a GWorld pointer (pRamp: 3 arrays of 256 elements each)
Boolean GetDeviceGammaRampCGP (CGrafPtr pGraf, Ptr pRamp); // retrieves the gamma ramp from a graphics device associated with a CGraf pointer (pRamp: 3 arrays of 256 elements each)
Boolean SetDeviceGammaRampGD (GDHandle hGD, Ptr pRamp); // sets the gamma ramp for a graphics device (pRamp: 3 arrays of 256 elements each (R,G,B))
Boolean SetDeviceGammaRampGW (GWorldPtr pGW, Ptr pRamp); // sets the gamma ramp for a graphics device associated with a GWorld pointer (pRamp: 3 arrays of 256 elements each (R,G,B))
Boolean SetDeviceGammaRampCGP (CGrafPtr pGraf, Ptr pRamp); // sets the gamma ramp for a graphics device associated with a CGraf pointer (pRamp: 3 arrays of 256 elements each (R,G,B))
