Fix haptic feedback when wrapping around zero degrees

tomo90 · Apr 30, 2023 · 560b5c2 · 560b5c2
1 parent 7dfa266
commit 560b5c2
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Showing 3 changed files with 40 additions and 16 deletions.
diff --git a/app/src/main/java/com/bobek/compass/util/MathUtils.kt b/app/src/main/java/com/bobek/compass/util/MathUtils.kt
@@ -23,7 +23,10 @@ import android.hardware.SensorManager
 import android.location.Location
 import com.bobek.compass.model.Azimuth
 import com.bobek.compass.model.DisplayRotation
-import com.bobek.compass.model.DisplayRotation.*
+import com.bobek.compass.model.DisplayRotation.ROTATION_0
+import com.bobek.compass.model.DisplayRotation.ROTATION_180
+import com.bobek.compass.model.DisplayRotation.ROTATION_270
+import com.bobek.compass.model.DisplayRotation.ROTATION_90
 import com.bobek.compass.model.RotationVector
 import kotlin.math.roundToInt
 
@@ -76,4 +79,13 @@ object MathUtils {
 
     fun getClosestNumberFromInterval(number: Float, interval: Float): Float =
         (number / interval).roundToInt() * interval
+
+    /**
+     * @see <a href="https://math.stackexchange.com/questions/2275439/check-if-point-on-circle-is-between-two-other-points-on-circle">Stackexchange</a>
+     */
+    fun isAzimuthBetweenTwoPoints(azimuth: Azimuth, pointA: Azimuth, pointB: Azimuth): Boolean {
+        val aToB = (pointB.degrees - pointA.degrees + 360f) % 360f
+        val aToAzimuth = (azimuth.degrees - pointA.degrees + 360f) % 360f
+        return aToB <= 180f != aToAzimuth > aToB
+    }
 }
diff --git a/app/src/main/java/com/bobek/compass/view/CompassView.kt b/app/src/main/java/com/bobek/compass/view/CompassView.kt
@@ -162,27 +162,20 @@ class CompassView(context: Context, attributes: AttributeSet) : ConstraintLayout
     private fun handleHapticFeedback(azimuth: Azimuth) {
         lastHapticFeedbackPoint
             ?.also { checkHapticFeedback(azimuth, it) }
-            ?: run { initializeLastHapticFeedbackPoint(azimuth) }
+            ?: run { updateLastHapticFeedbackPoint(azimuth) }
     }
 
-    private fun checkHapticFeedback(azimuth: Azimuth, lastHapticFeedbackkPoint: Azimuth) {
-        val boundaryStart = lastHapticFeedbackkPoint - HAPTIC_FEEDBACK_INTERVAL
-        val boundaryEnd = lastHapticFeedbackkPoint + HAPTIC_FEEDBACK_INTERVAL
+    private fun checkHapticFeedback(azimuth: Azimuth, lastHapticFeedbackPoint: Azimuth) {
+        val boundaryStart = lastHapticFeedbackPoint - HAPTIC_FEEDBACK_INTERVAL
+        val boundaryEnd = lastHapticFeedbackPoint + HAPTIC_FEEDBACK_INTERVAL
 
-        if (azimuth < boundaryStart) {
-            this.lastHapticFeedbackPoint = boundaryStart
-            performHapticFeedback()
-        } else if (azimuth > boundaryEnd) {
-            this.lastHapticFeedbackPoint = boundaryEnd
-            performHapticFeedback()
+        if (!MathUtils.isAzimuthBetweenTwoPoints(azimuth, boundaryStart, boundaryEnd)) {
+            updateLastHapticFeedbackPoint(azimuth)
+            performHapticFeedback(HapticFeedbackConstants.VIRTUAL_KEY)
         }
     }
 
-    private fun performHapticFeedback() {
-        performHapticFeedback(HapticFeedbackConstants.VIRTUAL_KEY)
-    }
-
-    private fun initializeLastHapticFeedbackPoint(azimuth: Azimuth) {
+    private fun updateLastHapticFeedbackPoint(azimuth: Azimuth) {
         val closestIntervalPoint = MathUtils.getClosestNumberFromInterval(azimuth.degrees, HAPTIC_FEEDBACK_INTERVAL)
         lastHapticFeedbackPoint = Azimuth(closestIntervalPoint)
     }

diff --git a/app/src/test/java/com/bobek/compass/util/MathUtilsTest.kt b/app/src/test/java/com/bobek/compass/util/MathUtilsTest.kt
@@ -18,7 +18,10 @@
 
 package com.bobek.compass.util
 
+import com.bobek.compass.model.Azimuth
 import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
 import org.junit.Test
 
 class MathUtilsTest {
@@ -60,4 +63,20 @@ class MathUtilsTest {
         assertEquals(0.4f, MathUtils.getClosestNumberFromInterval(0.39f, 0.2f))
         assertEquals(0.4f, MathUtils.getClosestNumberFromInterval(0.40f, 0.2f))
     }
+
+    @Test
+    fun isAzimuthBetweenTwoPoints() {
+        assertTrue(MathUtils.isAzimuthBetweenTwoPoints(Azimuth(10f), Azimuth(0f), Azimuth(20f)))
+        assertTrue(MathUtils.isAzimuthBetweenTwoPoints(Azimuth(20f), Azimuth(10f), Azimuth(30f)))
+
+        assertFalse(MathUtils.isAzimuthBetweenTwoPoints(Azimuth(180f), Azimuth(0f), Azimuth(20f)))
+        assertFalse(MathUtils.isAzimuthBetweenTwoPoints(Azimuth(180f), Azimuth(10f), Azimuth(30f)))
+
+        assertTrue(MathUtils.isAzimuthBetweenTwoPoints(Azimuth(359f), Azimuth(358f), Azimuth(2f)))
+        assertTrue(MathUtils.isAzimuthBetweenTwoPoints(Azimuth(0f), Azimuth(358f), Azimuth(2f)))
+        assertTrue(MathUtils.isAzimuthBetweenTwoPoints(Azimuth(1f), Azimuth(358f), Azimuth(2f)))
+
+        assertFalse(MathUtils.isAzimuthBetweenTwoPoints(Azimuth(357f), Azimuth(358f), Azimuth(2f)))
+        assertFalse(MathUtils.isAzimuthBetweenTwoPoints(Azimuth(3f), Azimuth(358f), Azimuth(2f)))
+    }
 }