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SetMode (csCode =2)

The required SetMode routine sets the pixel depth of the screen.



 
OSErr = Control(theDeviceRefNum, cscSetMode, &theVDPageInfo );



 
-->     csModeDesired   relative bit depth

--      csData          Unused

-->     csPage          Desired display page

<--     csBaseAddr      Base address of video RAM for this csMode

To improve the screen appearance during mode changes, devices with settable color tables should set all entries of the Color Lookup table (CLUT) to 50 percent gray before changing the mode. If the video card supports 16-bit or 32-bit pixel depths, the SetMode routine should set an internal flag to indicate direct mode operations.