Hand
class Hand : Trackable
Contains the tracking information of one of the user's hands.
Summary
Nested types |
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class Hand.State : Trackable.StateThe representation of the current state of a |
Public companion functions |
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HandSide |
getPrimaryHandSide(resolver: ContentResolver)Returns the handedness of the user's primary hand. |
Hand |
Returns the left hand. |
Hand |
Returns the right hand. |
Public properties |
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open StateFlow<Hand.State> |
The current |
Public companion functions
getPrimaryHandSide
Added in 1.0.0-alpha15
fun getPrimaryHandSide(resolver: ContentResolver): HandSide
Returns the handedness of the user's primary hand.
| Parameters | |
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resolver: ContentResolver |
the |
| Returns | |
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HandSide |
the |
left
Added in 1.0.0-alpha15
fun left(session: Session): Hand
Returns the left hand.
import androidx.xr.arcore.Hand import androidx.xr.arcore.HandJointType import androidx.xr.arcore.TrackingState import androidx.xr.runtime.math.Pose import androidx.xr.runtime.math.Vector3 val gestureRecognizer = object { private val gestureAnglesRange: Map<String, Array<Pair<Float, Float>>> = mapOf( "Thumb" to arrayOf( Pair(0.98f, 1f), // [0]palm to wrist Pair(0.41f, 0.88f), // [1]thumb to palm Pair(0.9f, 1f), // [2]thumb Pair(0.92f, 1f), // [3] Pair(0.55f, 0.94f), // [4]thumb to index Pair(-0.12f, 0.77f), // [5]index Pair(-0.37f, 0.49f), // [6] Pair(0.68f, 0.95f), // [7] Pair(0.93f, 1f), // [8]index to middle Pair(-0.08f, 0.73f), // [9]middle Pair(-0.26f, 0.52f), // [10] Pair(0.39f, 0.85f), // [11] Pair(0.96f, 1f), // [12]middle to ring Pair(-0.17f, 0.83f), // [13]ring Pair(-0.44f, 0.41f), // [14] Pair(0.52f, 0.87f), // [15] Pair(0.94f, 1f), // [16]ring to little Pair(-0.39f, 0.84f), // [17]little Pair(-0.48f, 0.61f), // [18] Pair(0.59f, 0.91f), // [19] ), "V" to arrayOf( Pair(0.98f, 1f), // [0]palm to wrist Pair(0.64f, 0.92f), // [1]thumb to palm Pair(0.74f, 0.96f), // [2]thumb Pair(0.88f, 0.99f), // [3] Pair(0.57f, 0.95f), // [4]thumb to index Pair(0.85f, 1f), // [5]index Pair(0.92f, 1f), // [6] Pair(0.98f, 1f), // [7] Pair(0.6f, 0.99f), // [8]index to middle Pair(0.37f, 0.99f), // [9]middle Pair(0.12f, 1f), // [10] Pair(0.66f, 1f), // [11] Pair(0.4f, 1f), // [12]middle to ring Pair(-0.06f, 0.91f), // [13]ring Pair(-0.26f, 0.96f), // [14] Pair(0.63f, 0.98f), // [15] Pair(0.76f, 0.99f), // [16]ring to little Pair(-0.47f, 0.78f), // [17]little Pair(0.01f, 0.97f), // [18] Pair(0.66f, 0.98f), // [19] ), "Heart" to arrayOf( Pair(0.98f, 1f), // [0]palm to wrist Pair(0.62f, 0.95f), // [1]thumb to palm Pair(0.95f, 1f), // [2]thumb Pair(0.88f, 0.99f), // [3] Pair(0.58f, 0.99f), // [4]thumb to index Pair(0.06f, 0.99f), // [5]index Pair(-0.2f, 0.91f), // [6] Pair(0.81f, 1f), // [7] Pair(0.31f, 1f), // [8]index to middle Pair(-0.12f, 0.79f), // [9]middle Pair(-0.3f, 0.55f), // [10] Pair(0.53f, 0.92f), // [11] Pair(0.92f, 1f), // [12]middle to ring Pair(-0.24f, 0.78f), // [13]ring Pair(-0.25f, 0.51f), // [14] Pair(0.58f, 0.90f), // [15] Pair(0.93f, 1f), // [16]ring to little Pair(-0.49f, 0.84f), // [17]little Pair(-0.16f, 0.64f), // [18] Pair(0.68f, 0.92f), // [19] ), ) private fun deriveAngles(handJoints: Map<HandJointType, Pose>): FloatArray { val directions: Array<Vector3> = arrayOf( handJoints[HandJointType.PALM]!!.forward, handJoints[HandJointType.WRIST]!!.forward, handJoints[HandJointType.THUMB_METACARPAL]!!.forward, handJoints[HandJointType.THUMB_PROXIMAL]!!.forward, handJoints[HandJointType.THUMB_DISTAL]!!.forward, handJoints[HandJointType.INDEX_METACARPAL]!!.forward, handJoints[HandJointType.INDEX_PROXIMAL]!!.forward, handJoints[HandJointType.INDEX_INTERMEDIATE]!!.forward, handJoints[HandJointType.INDEX_DISTAL]!!.forward, handJoints[HandJointType.MIDDLE_METACARPAL]!!.forward, handJoints[HandJointType.MIDDLE_PROXIMAL]!!.forward, handJoints[HandJointType.MIDDLE_INTERMEDIATE]!!.forward, handJoints[HandJointType.MIDDLE_DISTAL]!!.forward, handJoints[HandJointType.RING_METACARPAL]!!.forward, handJoints[HandJointType.RING_PROXIMAL]!!.forward, handJoints[HandJointType.RING_INTERMEDIATE]!!.forward, handJoints[HandJointType.RING_DISTAL]!!.forward, handJoints[HandJointType.LITTLE_METACARPAL]!!.forward, handJoints[HandJointType.LITTLE_PROXIMAL]!!.forward, handJoints[HandJointType.LITTLE_INTERMEDIATE]!!.forward, handJoints[HandJointType.LITTLE_DISTAL]!!.forward, ) return floatArrayOf( // palm to wrist directions[0].dot(directions[1]), // thumb to palm directions[0].dot(directions[2]), // thumb directions[2].dot(directions[3]), directions[3].dot(directions[4]), // thumb to index directions[2].dot(directions[5]), // index directions[5].dot(directions[6]), directions[6].dot(directions[7]), directions[7].dot(directions[8]), // index to middle directions[8].dot(directions[10]), // middle directions[9].dot(directions[10]), directions[10].dot(directions[11]), directions[11].dot(directions[12]), // middle to ring directions[10].dot(directions[14]), // ring directions[13].dot(directions[14]), directions[14].dot(directions[15]), directions[15].dot(directions[16]), // ring to little directions[14].dot(directions[18]), // little directions[17].dot(directions[18]), directions[18].dot(directions[19]), directions[19].dot(directions[20]), ) } private fun guessGesture(angleData: FloatArray): String { return gestureAnglesRange.entries .firstOrNull { (_, ranges) -> angleData.indices.all { i -> val (min, max) = ranges[i] angleData[i] in min..max } } ?.key ?: "Unknown" } fun parseJointsIntoGesture(handJoints: Map<HandJointType, Pose>): String { val angles = deriveAngles(handJoints) return guessGesture(angles) } } yourCoroutineScope.launch { Hand.left(session)?.state?.collect { leftHandState -> // early out since we only care if the hand is actively tracking. if (leftHandState.trackingState != TrackingState.TRACKING) return@collect val joints = leftHandState.handJoints when (gestureRecognizer.parseJointsIntoGesture(joints)) { "Thumb" -> { // Handle the user making a "thumbs up" gesture. } "Heart" -> { // Handle the user making a one-handed heart gesture. } "V" -> { // Handle the user making a "V" with their index and middle finger. } "Unknown" -> {} } // This function could also just interpret the joint poses to try and detect if the // user is making a specific gesture. yourRenderHandModelFunction(joints, isLeftHand = true) } }
| Throws | |
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IllegalStateException |
if |
right
Added in 1.0.0-alpha15
fun right(session: Session): Hand
Returns the right hand.
import androidx.xr.arcore.Hand import androidx.xr.arcore.HandJointType import androidx.xr.arcore.TrackingState import androidx.xr.runtime.math.Pose import androidx.xr.runtime.math.Vector3 val gestureRecognizer = object { private val gestureAnglesRange: Map<String, Array<Pair<Float, Float>>> = mapOf( "Thumb" to arrayOf( Pair(0.98f, 1f), // [0]palm to wrist Pair(0.41f, 0.88f), // [1]thumb to palm Pair(0.9f, 1f), // [2]thumb Pair(0.92f, 1f), // [3] Pair(0.55f, 0.94f), // [4]thumb to index Pair(-0.12f, 0.77f), // [5]index Pair(-0.37f, 0.49f), // [6] Pair(0.68f, 0.95f), // [7] Pair(0.93f, 1f), // [8]index to middle Pair(-0.08f, 0.73f), // [9]middle Pair(-0.26f, 0.52f), // [10] Pair(0.39f, 0.85f), // [11] Pair(0.96f, 1f), // [12]middle to ring Pair(-0.17f, 0.83f), // [13]ring Pair(-0.44f, 0.41f), // [14] Pair(0.52f, 0.87f), // [15] Pair(0.94f, 1f), // [16]ring to little Pair(-0.39f, 0.84f), // [17]little Pair(-0.48f, 0.61f), // [18] Pair(0.59f, 0.91f), // [19] ), "V" to arrayOf( Pair(0.98f, 1f), // [0]palm to wrist Pair(0.64f, 0.92f), // [1]thumb to palm Pair(0.74f, 0.96f), // [2]thumb Pair(0.88f, 0.99f), // [3] Pair(0.57f, 0.95f), // [4]thumb to index Pair(0.85f, 1f), // [5]index Pair(0.92f, 1f), // [6] Pair(0.98f, 1f), // [7] Pair(0.6f, 0.99f), // [8]index to middle Pair(0.37f, 0.99f), // [9]middle Pair(0.12f, 1f), // [10] Pair(0.66f, 1f), // [11] Pair(0.4f, 1f), // [12]middle to ring Pair(-0.06f, 0.91f), // [13]ring Pair(-0.26f, 0.96f), // [14] Pair(0.63f, 0.98f), // [15] Pair(0.76f, 0.99f), // [16]ring to little Pair(-0.47f, 0.78f), // [17]little Pair(0.01f, 0.97f), // [18] Pair(0.66f, 0.98f), // [19] ), "Heart" to arrayOf( Pair(0.98f, 1f), // [0]palm to wrist Pair(0.62f, 0.95f), // [1]thumb to palm Pair(0.95f, 1f), // [2]thumb Pair(0.88f, 0.99f), // [3] Pair(0.58f, 0.99f), // [4]thumb to index Pair(0.06f, 0.99f), // [5]index Pair(-0.2f, 0.91f), // [6] Pair(0.81f, 1f), // [7] Pair(0.31f, 1f), // [8]index to middle Pair(-0.12f, 0.79f), // [9]middle Pair(-0.3f, 0.55f), // [10] Pair(0.53f, 0.92f), // [11] Pair(0.92f, 1f), // [12]middle to ring Pair(-0.24f, 0.78f), // [13]ring Pair(-0.25f, 0.51f), // [14] Pair(0.58f, 0.90f), // [15] Pair(0.93f, 1f), // [16]ring to little Pair(-0.49f, 0.84f), // [17]little Pair(-0.16f, 0.64f), // [18] Pair(0.68f, 0.92f), // [19] ), ) private fun deriveAngles(handJoints: Map<HandJointType, Pose>): FloatArray { val directions: Array<Vector3> = arrayOf( handJoints[HandJointType.PALM]!!.forward, handJoints[HandJointType.WRIST]!!.forward, handJoints[HandJointType.THUMB_METACARPAL]!!.forward, handJoints[HandJointType.THUMB_PROXIMAL]!!.forward, handJoints[HandJointType.THUMB_DISTAL]!!.forward, handJoints[HandJointType.INDEX_METACARPAL]!!.forward, handJoints[HandJointType.INDEX_PROXIMAL]!!.forward, handJoints[HandJointType.INDEX_INTERMEDIATE]!!.forward, handJoints[HandJointType.INDEX_DISTAL]!!.forward, handJoints[HandJointType.MIDDLE_METACARPAL]!!.forward, handJoints[HandJointType.MIDDLE_PROXIMAL]!!.forward, handJoints[HandJointType.MIDDLE_INTERMEDIATE]!!.forward, handJoints[HandJointType.MIDDLE_DISTAL]!!.forward, handJoints[HandJointType.RING_METACARPAL]!!.forward, handJoints[HandJointType.RING_PROXIMAL]!!.forward, handJoints[HandJointType.RING_INTERMEDIATE]!!.forward, handJoints[HandJointType.RING_DISTAL]!!.forward, handJoints[HandJointType.LITTLE_METACARPAL]!!.forward, handJoints[HandJointType.LITTLE_PROXIMAL]!!.forward, handJoints[HandJointType.LITTLE_INTERMEDIATE]!!.forward, handJoints[HandJointType.LITTLE_DISTAL]!!.forward, ) return floatArrayOf( // palm to wrist directions[0].dot(directions[1]), // thumb to palm directions[0].dot(directions[2]), // thumb directions[2].dot(directions[3]), directions[3].dot(directions[4]), // thumb to index directions[2].dot(directions[5]), // index directions[5].dot(directions[6]), directions[6].dot(directions[7]), directions[7].dot(directions[8]), // index to middle directions[8].dot(directions[10]), // middle directions[9].dot(directions[10]), directions[10].dot(directions[11]), directions[11].dot(directions[12]), // middle to ring directions[10].dot(directions[14]), // ring directions[13].dot(directions[14]), directions[14].dot(directions[15]), directions[15].dot(directions[16]), // ring to little directions[14].dot(directions[18]), // little directions[17].dot(directions[18]), directions[18].dot(directions[19]), directions[19].dot(directions[20]), ) } private fun guessGesture(angleData: FloatArray): String { return gestureAnglesRange.entries .firstOrNull { (_, ranges) -> angleData.indices.all { i -> val (min, max) = ranges[i] angleData[i] in min..max } } ?.key ?: "Unknown" } fun parseJointsIntoGesture(handJoints: Map<HandJointType, Pose>): String { val angles = deriveAngles(handJoints) return guessGesture(angles) } } yourCoroutineScope.launch { Hand.right(session)?.state?.collect { rightHandState -> // early out since we only care if the hand is actively tracking. if (rightHandState.trackingState != TrackingState.TRACKING) return@collect val joints = rightHandState.handJoints when (gestureRecognizer.parseJointsIntoGesture(joints)) { "Thumb" -> { // Handle the user making a "thumbs up" gesture. } "Heart" -> { // Handle the user making a one-handed heart gesture. } "V" -> { // Handle the user making a "V" with their index and middle finger. } "Unknown" -> {} } // This function could also just interpret the joint poses to try and detect if the // user is making a specific gesture. yourRenderHandModelFunction(joints, isLeftHand = false) } }
| Throws | |
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IllegalStateException |
if |