video-glasses-sdk/com.kaleyra.video_glasses_sdk.utils/GlassGestureDetector

GlassGestureDetector

class GlassGestureDetector(context: Context, onGestureListener: GlassGestureDetector.OnGestureListener)

Gesture detector for Google Glass usage purposes.

It detects one and two finger gestures like:

TAP
TAP_AND_HOLD
TWO_FINGER_TAP
SWIPE_FORWARD
TWO_FINGER_SWIPE_FORWARD
SWIPE_BACKWARD
TWO_FINGER_SWIPE_BACKWARD
SWIPE_UP
TWO_FINGER_SWIPE_UP
SWIPE_DOWN
TWO_FINGER_SWIPE_DOWN

Swipe detection depends on the:

movement tan value
movement distance
movement velocity

To prevent unintentional SWIPE_DOWN, TWO_FINGER_SWIPE_DOWN, SWIPE_UP and TWO_FINGER_SWIPE_UP gestures, they are detected if movement angle is only between 60 and 120 degrees to the Glass touchpad horizontal axis. Any other detected swipes, will be considered as SWIPE_FORWARD and SWIPE_BACKWARD gestures, depends on the sign of the axis x movement value.

 ______________________________________________________________
|                     \        UP         /                    |
|                       \               /                      |
|                         60         120                       |
|                           \       /                          |
|                             \   /                            |
|  BACKWARD  <-------  0  ------------  180  ------>  FORWARD  |
|                             /   \                            |
|                           /       \                          |
|                         60         120                       |
|                       /               \                      |
|                     /       DOWN        \                    |
 --------------------------------------------------------------