Static int
compute_delta(struct tpms_softc *sc, int *dx, int *dy, int *dz,
uint32_t * buttons)
{
int x_det, y_det, x_raw, y_raw, x_fingers, y_fingers, fingers, x, y;
x_det = detect_pos(sc->sc_acc, sc->sc_x_sensors, sc->sc_threshold,
sc->sc_x_factor, &x_raw, &x_fingers);
y_det = detect_pos(sc->sc_acc + TPMS_X_SENSORS, sc->sc_y_sensors,
sc->sc_threshold, sc->sc_y_factor,
&y_raw, &y_fingers);
fingers = max(x_fingers, y_fingers);
/* Check the number of fingers and if we have detected a position. */
if (fingers > 1) {
/* More than one finger detected, resetting. */
memset(sc->sc_acc, 0, sizeof(sc->sc_acc));
sc->sc_x_raw = sc->sc_y_raw = sc->sc_x = sc->sc_y = -1;
return 0;
} else if (x_det == 0 && y_det == 0) {
/* No position detected, resetting. */
memset(sc->sc_acc, 0, sizeof(sc->sc_acc));
sc->sc_x_raw = sc->sc_y_raw = sc->sc_x = sc->sc_y = -1;
} else if (x_det > 0 && y_det > 0) {
/* Smooth position. */
if (sc->sc_x_raw >= 0) {
sc->sc_x_raw = (3 * sc->sc_x_raw + x_raw) / 4;
sc->sc_y_raw = (3 * sc->sc_y_raw + y_raw) / 4;
/*
* Compute virtual position and change if we already
* have a decent position.
*/
if (sc->sc_x >= 0) {
x = smooth_pos(sc->sc_x, sc->sc_x_raw,
sc->sc_noise);
y = smooth_pos(sc->sc_y, sc->sc_y_raw,
sc->sc_noise);
*dx = x - sc->sc_x;
*dy = y - sc->sc_y;
sc->sc_x = x;
sc->sc_y = y;
} else {
/* Initialise virtual position. */
sc->sc_x = sc->sc_x_raw;
sc->sc_y = sc->sc_y_raw;
}
} else {
/* Initialise raw position. */
sc->sc_x_raw = x_raw;
sc->sc_y_raw = y_raw;
}
}
return (1);
}
/*
* Compute the change in x, y and z direction, update the button state
* (to simulate more than one button, scrolling etc.), and update the
* history. Note that dx, dy, dz and buttons are modified only if
* corresponding pressure is detected and should thus be initialised
* before the call. Return 0 on error.
*
* XXX Could we report something useful in dz?
*/
int
compute_delta(struct utpms_softc *sc, int *dx, int *dy, int *dz,
uint32_t * buttons)
{
int x_det, y_det, x_raw, y_raw, x_fingers, y_fingers, fingers, x, y;
x_det = detect_pos(sc->sc_acc, sc->sc_x_sensors, sc->sc_threshold,
sc->sc_x_factor, &x_raw, &x_fingers);
y_det = detect_pos(sc->sc_acc + UTPMS_X_SENSORS, sc->sc_y_sensors,
sc->sc_threshold, sc->sc_y_factor,
&y_raw, &y_fingers);
fingers = max(x_fingers, y_fingers);
/* Check the number of fingers and if we have detected a position. */
if (x_det == 0 && y_det == 0) {
/* No position detected, resetting. */
bzero(sc->sc_acc, sizeof(sc->sc_acc));
sc->sc_x_raw = sc->sc_y_raw = sc->sc_x = sc->sc_y = -1;
} else if (x_det > 0 && y_det > 0) {
switch (fingers) {
case 1:
/* Smooth position. */
if (sc->sc_x_raw >= 0) {
sc->sc_x_raw = (3 * sc->sc_x_raw + x_raw) / 4;
sc->sc_y_raw = (3 * sc->sc_y_raw + y_raw) / 4;
/*
* Compute virtual position and change if we
* already have a decent position.
*/
if (sc->sc_x >= 0) {
x = smooth_pos(sc->sc_x, sc->sc_x_raw,
sc->sc_noise);
y = smooth_pos(sc->sc_y, sc->sc_y_raw,
sc->sc_noise);
*dx = x - sc->sc_x;
*dy = y - sc->sc_y;
sc->sc_x = x;
sc->sc_y = y;
} else {
/* Initialise virtual position. */
sc->sc_x = sc->sc_x_raw;
sc->sc_y = sc->sc_y_raw;
}
} else {
/* Initialise raw position. */
sc->sc_x_raw = x_raw;
sc->sc_y_raw = y_raw;
}
break;
case 2:
if (*buttons == 1)
*buttons = 4;
break;
case 3:
if (*buttons == 1)
*buttons = 2;
break;
}
}
return (1);
}
