giiQueryValInfo(3gii)

NAME
giiQueryValInfo - Get data about valuators

SYNOPSIS
#include <ggi/gii.h>

int giiQueryValInfo(gii_input_t*inp, uint32 origin, uint32 valnumber, gii_cmddata_getdevinfo *info); .SH "DESCRIPTION"

Though when using GII inputs the exact type of device is fully transparent to the program, information about the device that is actually attached to a given gii input and origin id can be queried, e.g. for configuration interfaces.

For giiQueryValInfo is used on devices, where giiQueryDeviceInfo has indicated that the device has one or more valuator axes and you want to gather additional info about the physical equivalent of each axis.The parameters inp and origin select the input to query and valnumber selects the specific valuator (an input can have multiple valuators).

The queried data is put into info, which has the following fields:

number
    Number of the queried valuator.

longname
    Name of the device (string, 74+\0 chars max)

shortname
    Abbreviated devicename (string, 4+\0 chars max)

gii_valrange range
    struct with sint32 min,center, max; Contains the minimum, center and maximum values for this valuator. Note, that this range may change on some devices due to calibration, but it is usually not expected that a device recalibrates while in use. You should react gracefully to values received from the valuator that are outside the specified range, though.

gii_phystype phystype
    gives the physical quantity the device measures. The idea is to report the thing the user actually controls. I.e. a Joystick actually measures resistance, but should report GII_PT_ANGLE or GII_PT_FORCE, as that is what the user does to the stick and what results in the changed resistance.

sint32 SI_add,SI_mul,SI_div,SI_shift
    Using these values, it is possible to give calibration data to the application. In gii.h there is a base unit (according to SI) specified for each phystype. The SI value can be computed using these values and the following formula (unless SI_mul is 0, which means the device is non-linear or the factor is unknown). SI = (float) (SI_add + value[n]) * (float) SI_mul / (float) SI_div * pow(2.0, SI_shift);

RETURN VALUE

Returns 0 on success (info is valid, then) or -1 otherwise.

SEE ALSO
giiQueryDeviceInfo