car: the card column only moves the map's center, so Vela's speedometer keeps its size

gearslip/src/main/java/app/seb3thehacker/gearslip/car/CarAppStage.kt

@@ -102,10 +102,18 @@ private fun AppSurface(
     // changing size moves the visible area even though the surface itself hasn't changed.
     val (width, height) = size
     val measured = bounds?.takeIf { width > 0 && height > 0 }?.let { cover?.visibleWithin(it, width, height) }
-    LaunchedEffect(template, size, measured) {
+    // The card column moves the map's centre but isn't taken out of the stable area: apps size
+    // their own overlays from it, and Vela's speedometer shrank to fit the strip right of the cards.
+    val measuredStable = bounds?.takeIf { width > 0 && height > 0 }?.let { cover?.visibleWithin(it, width, height, skip = CoverEdge.START) }
+    LaunchedEffect(template, size, measured, measuredStable) {
         if (width > 0 && height > 0) {
             val visible = visibleAreaFor(template, width, height, measured)
-            connection.reportAreas(visible = visible, stable = visible)
+            val stable = if (template is androidx.car.app.navigation.model.NavigationTemplate) {
+                visibleAreaFor(template, width, height, measuredStable)
+            } else {
+                visible
+            }
+            connection.reportAreas(visible = visible, stable = stable)
         }
     }
 

gearslip/src/main/java/app/seb3thehacker/gearslip/car/TemplateChrome.kt

@@ -129,12 +129,13 @@ internal class ChromeCover {
     }
 
     /** What is left of a [width] x [height] surface at [surface] (window pixels), in surface pixels. */
-    fun visibleWithin(surface: ComposeRect, width: Int, height: Int): Rect {
+    fun visibleWithin(surface: ComposeRect, width: Int, height: Int, skip: CoverEdge? = null): Rect {
         var left = 0f
         var top = 0f
         var right = width.toFloat()
         var bottom = height.toFloat()
         pieces.values.forEach { (edge, b) ->
+            if (edge == skip) return@forEach
             when (edge) {
                 CoverEdge.TOP -> top = maxOf(top, b.bottom - surface.top)
                 CoverEdge.BOTTOM -> bottom = minOf(bottom, b.top - surface.top)