Carrol Touch TouchSystems CarrollTouch Prog, Руководство программиста

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Chapter 7 - CTKERN CARROLL TOUCH
7-4 Touch System Programmer’s Guide
Scaling
CTKERN has the ability to scale the touch coordinates to a
user-defined coordinate system. There are three options for scaling:
disabled, fixed, and automatic.
If scaling is disabled, the touch coordinates reported by CTKERN are
not scaled.
If fixed scaling is selected, the touch coordinates reported by CTKERN
are scaled using 0, 0 for the upper left x and y scaling parameters and
(Xres - 1, Yres - 1) from the calibration parameters of the default
calibration entry for the lower right x and y scaling parameters, then are
passed on to the application program. If no calibration entry is marked
as the default, the Xres, Yres values of the first calibration entry
(calibration table index 0) are used.
If automatic scaling is selected, the touch coordinates reported by
CTKERN are scaled using 0, 0 for the upper left x and y scaling
parameters and (Xres - 1, Yres - 1) from the calibration parameters for
the currently selected BIOS video mode for the lower right x and y
scaling parameters, then are passed on to the application program. The
driver determines the video mode by intercepting calls to BIOS mode
10H function 0 (Set Video Mode). If an entry in the table of calibration
parameters that corresponds to that video mode exists, the Xres, Yres
values of those calibration parameters are used. If no such entry exists,
the Xres, Yres values of the default calibration parameters are used. If
no calibration entry is marked as the default, the Xres, Yres values of
the first calibration entry (calibration table index 0) are used.
SetScalingParameters (9) may also be used to set the scaling
parameters to arbitrary values that are not related to the Xres and Yres
parameters in any calibration table entry.
CTKERN has the ability to scale the z-axis pressure parameter returned
by touch systems that support z-axis pressure detection. There are only
two options for z-axis scaling: disabled and enabled. When z-axis
scaling is disabled, the raw z-axis parameter reported by the touch
system is reported by CTKERN. If z-axis scaling is enabled, the z-axis
parameter reported by the touch system is scaled linearly within the
range defined by user-definable minimum and maximum pressure
values.