ref #8: Replace fixed arrow images, use gps bearing, moving average

app/src/main/kotlin/de/timklge/karooheadwind/Extensions.kt

@@ -27,6 +27,7 @@ import kotlinx.coroutines.flow.filterNotNull
 import kotlinx.coroutines.flow.flowOf
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.mapNotNull
+import kotlinx.coroutines.flow.scan
 import kotlinx.coroutines.flow.single
 import kotlinx.coroutines.flow.timeout
 import kotlinx.coroutines.time.debounce
@@ -167,24 +168,36 @@ fun KarooSystemService.getRelativeHeadingFlow(context: Context): Flow<Double> {
 
     return getHeadingFlow()
         .filter { it >= 0 }
-        .combine(currentWeatherData) { cardinalDirection, data -> cardinalDirection to data }
-        .map { (cardinalDirection, data) ->
-            val bearing = cardinalDirection * 45.0
+        .combine(currentWeatherData) { bearing, data -> bearing to data }
+        .map { (bearing, data) ->
             val windBearing = data.current.windDirection + 180
-            val diff = (signedAngleDifference(bearing, windBearing) + 360) % 360
+            val diff = signedAngleDifference(bearing, windBearing)
             Log.d(KarooHeadwindExtension.TAG, "Wind bearing: $bearing vs $windBearing => $diff")
 
             diff
         }
 }
 
-fun KarooSystemService.getHeadingFlow(): Flow<Int> {
-    // return flowOf(2)
+fun Double.lerp(target: Double, alpha: Double): Double {
+    return this + (target - this) * alpha
+}
 
-    return streamDataFlow(DataType.Type.HEADING)
-        .mapNotNull { (it as? StreamState.Streaming)?.dataPoint?.singleValue }
-        .map { it.roundToInt() }
+fun KarooSystemService.getHeadingFlow(): Flow<Double> {
+    //return flowOf(20.0)
+
+    return streamDataFlow("TYPE_LOCATION_ID")
+        .mapNotNull { (it as? StreamState.Streaming)?.dataPoint?.values }
+        .map { values ->
+            val heading = values[DataType.Field.LOC_BEARING]
+
+            heading ?: 0.0
+        }
         .distinctUntilChanged()
+        .scan(emptyList<Double>()) { acc, value ->
+            val newAcc = acc + value
+            if (newAcc.size > 3) newAcc.drop(1) else newAcc
+        }
+        .map { it.average() }
 }
 
 @OptIn(FlowPreview::class)

app/src/main/kotlin/de/timklge/karooheadwind/datatypes/HeadwindDirectionDataType.kt

@@ -7,7 +7,6 @@ import androidx.glance.appwidget.ExperimentalGlanceRemoteViewsApi
 import androidx.glance.appwidget.GlanceRemoteViews
 import de.timklge.karooheadwind.KarooHeadwindExtension
 import de.timklge.karooheadwind.OpenMeteoCurrentWeatherResponse
-import de.timklge.karooheadwind.getHeadingFlow
 import de.timklge.karooheadwind.getRelativeHeadingFlow
 import de.timklge.karooheadwind.screens.HeadwindSettings
 import de.timklge.karooheadwind.streamCurrentWeatherData

app/src/main/kotlin/de/timklge/karooheadwind/datatypes/HeadwindDirectionView.kt

@@ -1,7 +1,15 @@
 package de.timklge.karooheadwind.datatypes
 
+import android.R
+import android.content.res.Resources
+import android.graphics.Bitmap
+import android.graphics.BitmapFactory
+import android.graphics.Canvas
+import android.graphics.Paint
+import android.graphics.Path
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.StrokeCap
 import androidx.compose.ui.unit.TextUnit
 import androidx.compose.ui.unit.TextUnitType
 import androidx.compose.ui.unit.dp
@@ -9,6 +17,7 @@ import androidx.glance.ColorFilter
 import androidx.glance.GlanceModifier
 import androidx.glance.Image
 import androidx.glance.ImageProvider
+import androidx.glance.LocalContext
 import androidx.glance.background
 import androidx.glance.color.ColorProvider
 import androidx.glance.layout.Alignment
@@ -20,27 +29,45 @@ import androidx.glance.preview.ExperimentalGlancePreviewApi
 import androidx.glance.preview.Preview
 import androidx.glance.text.Text
 import androidx.glance.text.TextStyle
-import de.timklge.karooheadwind.R
 import kotlin.math.roundToInt
 
-fun getArrowResourceByBearing(bearing: Int): Int {
-    val oclock = ((bearing % 360) / 30.0).roundToInt()
 
-    return when (oclock){
-        0 -> R.drawable.arrow_0
-        1 -> R.drawable.arrow_1
-        2 -> R.drawable.arrow_2
-        3 -> R.drawable.arrow_3
-        4 -> R.drawable.arrow_4
-        5 -> R.drawable.arrow_5
-        6 -> R.drawable.arrow_6
-        7 -> R.drawable.arrow_7
-        8 -> R.drawable.arrow_8
-        9 -> R.drawable.arrow_9
-        10 -> R.drawable.arrow_10
-        11 -> R.drawable.arrow_11
-        12 -> R.drawable.arrow_0
-        else -> error("Bearing $bearing out of range")
+val bitmapsByBearing = mutableMapOf<Int, Bitmap>()
+
+fun getArrowBitmapByBearing(bearing: Int): Bitmap {
+    synchronized(bitmapsByBearing) {
+        val bearingRounded = (((bearing + 360) / 5.0).roundToInt() * 5) % 360
+
+        val storedBitmap = bitmapsByBearing[bearingRounded]
+        if (storedBitmap != null) return storedBitmap
+
+        val bitmap = Bitmap.createBitmap(128, 128, Bitmap.Config.ARGB_8888)
+        val canvas = Canvas(bitmap)
+
+        val paint = Paint().apply {
+            color = android.graphics.Color.WHITE
+            style = Paint.Style.STROKE
+            strokeWidth = 15f
+            isAntiAlias = true
+        }
+
+        val path = Path().apply {
+            moveTo(64f, 0f) // Top point of the arrow
+            lineTo(128f, 128f) // Bottom right point of the arrow
+            lineTo(64f, 96f) // Middle bottom point of the arrow
+            lineTo(0f, 128f) // Bottom left point of the arrow
+            close() // Close the path to form the arrow shape
+        }
+
+        canvas.save()
+        canvas.rotate(bearing.toFloat(), 64f, 64f) // Rotate the canvas based on the bearing
+        canvas.scale(0.75f, 0.75f, 64f, 64f) // Scale the arrow down to fit the canvas
+        canvas.drawPath(path, paint)
+        canvas.restore()
+
+        bitmapsByBearing[bearingRounded] = bitmap
+
+        return bitmap
     }
 }
 
@@ -57,7 +84,7 @@ fun HeadwindDirection(bearing: Int, fontSize: Int, overlayText: String? = null)
     ) {
         Image(
                 modifier = GlanceModifier.fillMaxSize(),
-                provider = ImageProvider(getArrowResourceByBearing(bearing)),
+                provider = ImageProvider(getArrowBitmapByBearing(bearing)),
                 contentDescription = "Relative wind direction indicator",
                 contentScale = ContentScale.Fit,
                 colorFilter = ColorFilter.tint(ColorProvider(Color.Black, Color.White))

app/src/main/kotlin/de/timklge/karooheadwind/datatypes/WeatherDataType.kt

@@ -8,7 +8,6 @@ import androidx.glance.appwidget.GlanceRemoteViews
 import de.timklge.karooheadwind.KarooHeadwindExtension
 import de.timklge.karooheadwind.OpenMeteoCurrentWeatherResponse
 import de.timklge.karooheadwind.WeatherInterpretation
-import de.timklge.karooheadwind.getHeadingFlow
 import de.timklge.karooheadwind.screens.HeadwindSettings
 import de.timklge.karooheadwind.streamCurrentWeatherData
 import de.timklge.karooheadwind.streamSettings
@@ -25,7 +24,6 @@ import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.awaitCancellation
 import kotlinx.coroutines.flow.combine
-import kotlinx.coroutines.flow.filter
 import kotlinx.coroutines.flow.onCompletion
 import kotlinx.coroutines.launch
 import kotlin.math.roundToInt

app/src/main/kotlin/de/timklge/karooheadwind/datatypes/WeatherView.kt

@@ -9,6 +9,7 @@ import androidx.glance.ColorFilter
 import androidx.glance.GlanceModifier
 import androidx.glance.Image
 import androidx.glance.ImageProvider
+import androidx.glance.LocalContext
 import androidx.glance.color.ColorProvider
 import androidx.glance.layout.Alignment
 import androidx.glance.layout.Column
@@ -57,7 +58,7 @@ fun Weather(current: WeatherInterpretation, windBearing: Int, windSpeed: Int, wi
         Row(horizontalAlignment = Alignment.CenterHorizontally, verticalAlignment = Alignment.CenterVertically) {
             Image(
                 modifier = GlanceModifier.height(20.dp).width(12.dp),
-                provider = ImageProvider(getArrowResourceByBearing(windBearing)),
+                provider = ImageProvider(getArrowBitmapByBearing(windBearing)),
                 contentDescription = "Current wind direction",
                 contentScale = ContentScale.Fit,
                 colorFilter = ColorFilter.tint(ColorProvider(Color.Black, Color.White))