Specifications

CHAPTER 3
Application Program Interface
36 VPTEngine Component
VPTEngineCalibrateDisplay 3
This function allows the caller to force the display to go through a calibration cycle. Your
application probably will not need to call this function, since the software included with
the AppleVision display causes the display to be recalibrated automatically every two
weeks or so.
pascal VPTEngineResult
VPTEngineCalibrateDisplay( VPTEngineComponent engineComponent
engineComponent
A valid instance of the VPTEngine component.
Supplementary Information
Calling this function causes the entire Macintosh system to stop whatever it is doing and
spend several moments recalibrating the display. During this time, the entire screen
flashes black, white, and several other colors.
VPTEngineCalibrated 3
This function allows your application to determine whether or not the display is
currently in a calibrated state.
pascal VPTEngineResult
VPTEngineCalibrated( VPTEngineComponent engineComponent,
Boolean* calibrated )
engineComponent
A valid instance of the VPTEngine component.
calibrated Set to true if the display is in a calibrated state.
Supplementary Information
In general, the only time this function will return false for the calibrated parameter
is when the AppleVision software finds itself with no preference file on the startup drive
and has not yet asked the user to recalibrate. This brief interval usually lasts about 15
minutes (the amount of time it takes the display to warm up fully) but for color-critical
applications, this function should be called before relying on the information provided
through the VPTEngine component interface.
VPTEngineGetLastCalTime 3
This function returns the date & time (represented as the number of seconds elapsed
since midnight, January 1, 1994) that the display was last calibrated.
pascal VPTEngineResult
VPTEngineGetLastCalTime( VPTEngineComponent engineComponent
unsigned long* lastCalTime )