Carrol Touch TouchSystems CarrollTouch Prog, Руководство программиста

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CARROLL TOUCH Chapter 7 - CTKERN
Touch System Programmer’s Guide 7-5
Touch Reporting
The application program may get touch reporting information from
CTKERN either by calling GetTouchState (1) that returns the current
touch state, or by setting up a user event handler that is called whenever
the touch state changes by using SetUserEventHandlerMode (23).
Possible touch states are:
NT Not touched, with scaled (if enabled), calibrated (if enabled)
coordinates of the last place the screen was touched. If the
screen has not been touched since the driver was last loaded
or reset, the coordinates returned are 0, 0.
TO Touched, with scaled (if enabled), calibrated (if enabled)
coordinates of where the screen is currently being touched.
NC Non-contiguous.
The touch state is automatically maintained by CTKERN using an
interrupt-driven background process.
CTKERN also includes SetTouchState (2) to manually set the touch
state to a user-specified state. This can be useful for debugging and so
forth.
Calibration and Scaling Examples
Because the calibration and scaling modes of CTKERN may be
independently set, there are four possible combinations of calibration
and scaling modes, as shown in Figure 7-2 through 7-5:
Figure 7-2: Calibration mode = Fixed or automatic
Scaling mode
= Fixed or automatic
Figure 7-3: Calibration mode = Fixed or automatic
Scaling mode
= Disabled
Figure 7-4: Calibration mode = Disabled
Scaling mode
= Fixed or automatic
Figure 7-5: Calibration mode = Disabled
Scaling mode
= Disabled
Each figure illustrates the touch coordinates that are returned for that
particular combination of calibration and scaling modes. The touch