Reads and returns the gamma table 'gammatable' of the specified screen or window
'windowPtrOrScreenNumber'. Returns the output resolution of the video DAC as
optional second argument 'dacbits'. Will return dacbits=8 as a safe default if
it is unable to query the real resolution of the DAC. Currently only OS-X
reports the real DAC size. Will return the real number of slots in the hardware
lookup table in optional return argument 'reallutsize'. Currently only OS-X
reports the real LUT size.
On
MacOS-X, the optional 'physicalDisplay' flag can be set to 1, zero is the
default. In this case, the 'windowPtrOrScreenNumber' argument (which then must
be a real screen number, not a window index) selects among physically present
display devices, instead of logical devices. This is important if you want to
assign different gamma-tables to multiple displays in a 'clone' or 'mirror mode'
configuration, as there is only one logical display, but multiple physical
displays, mirroring each other. Please note that screen numbering is different
for physical vs. logical displays. For a list of physical display indices, call
Screen('Screens', 1);
See help for
Screen('
LoadNormalizedGammaTable'); for infos about the format of
the returned table and for further explanations regarding gamma tables.