Apply display density to topology pane scaling

Account for high DPI screens in topology pane scaling.

Flag: com.android.settings.flags.display_topology_pane_in_display_list
Bug: b/352650922
Test: atest DisplayTopologyPreferenceTest.kt
Test: atest TopologyScaleTest.kt
Test: compare appearance on mid-dpi and high-dpi screens with a single 1080p external display
Change-Id: I192fccd402c20e00beacdb5ad55eed406252eb93

src/com/android/settings/connecteddevice/display/DisplayTopology.kt

@@ -35,7 +35,9 @@ import android.hardware.display.DisplayTopology.TreeNode.POSITION_BOTTOM
 import android.hardware.display.DisplayTopology.TreeNode.POSITION_LEFT
 import android.hardware.display.DisplayTopology.TreeNode.POSITION_RIGHT
 import android.hardware.display.DisplayTopology.TreeNode.POSITION_TOP
+import android.util.DisplayMetrics
 import android.util.Log
+import android.view.DisplayInfo
 import android.view.MotionEvent
 import android.view.ViewGroup
 import android.view.ViewTreeObserver
@@ -84,7 +86,7 @@ fun Float.atLeast(n: Number): Float = max(this, n.toFloat())
  * @param displaysPos the absolute topology coordinates for each display in the topology.
  */
 class TopologyScale(
-        paneWidth: Int, minPaneHeight: Float, minEdgeLength: Int, maxBlockRatio: Float,
+        paneWidth: Int, minPaneHeight: Float, minEdgeLength: Float, maxBlockRatio: Float,
         displaysPos: Collection<RectF>) {
     /** Scale of block sizes to real-world display sizes. Should be less than 1. */
     val blockRatio: Float
@@ -120,7 +122,7 @@ class TopologyScale(
                 // If the `ratio` is set too low because one of the displays will have an edge less
                 // than minEdgeLength(dp) long, increase it such that the smallest edge is that
                 // long.
-                .atLeast(minEdgeLength.toFloat() / smallestDisplayDim)
+                .atLeast(minEdgeLength / smallestDisplayDim)
 
         // Essentially, we just set the pane height based on the pre-determined pane width and the
         // aspect ratio of the display bounds.
@@ -308,6 +310,16 @@ class DisplayTopologyPreference(context : Context)
         open val wallpaper: Bitmap?
             get() = WallpaperManager.getInstance(context).bitmap
 
+        open val densityDpi: Int
+            get() {
+                val info = DisplayInfo()
+                return if (context.display.getDisplayInfo(info)) {
+                    info.logicalDensityDpi
+                } else {
+                    DisplayMetrics.DENSITY_DEFAULT
+                }
+            }
+
         open fun registerTopologyListener(listener: Consumer<DisplayTopology>) {
             displayManager.registerTopologyListener(context.mainExecutor, listener)
         }
@@ -395,9 +407,14 @@ class DisplayTopologyPreference(context : Context)
             recycleableBlocks.add(mPaneContent.getChildAt(i) as DisplayBlock)
         }
 
+        // This density is the density of the current display (showing the topology pane). It is
+        // necessary to use this density here because the topology pane coordinates are in physical
+        // pixels, and the display coordinates are in density-independent pixels.
+        val dpi = injector.densityDpi
         val scaling = TopologyScale(
                 mPaneContent.width, minPaneHeight = mTopologyInfo?.scaling?.paneHeight ?: 0f,
-                minEdgeLength = 60, maxBlockRatio = 0.12f,
+                minEdgeLength = DisplayTopology.dpToPx(60f, dpi),
+                maxBlockRatio = DisplayTopology.dpToPx(0.12f, dpi),
                 newBounds.map { it.second }.toList())
         mPaneHolder.layoutParams.let {
             val newHeight = scaling.paneHeight.toInt()

tests/robotests/src/com/android/settings/connecteddevice/display/DisplayTopologyPreferenceTest.kt

@@ -25,6 +25,7 @@ import android.graphics.Bitmap
 import android.graphics.Color
 import android.graphics.drawable.Drawable
 import android.hardware.display.DisplayTopology
+import android.util.DisplayMetrics
 import android.view.MotionEvent
 import android.view.View
 import android.widget.FrameLayout
@@ -71,6 +72,8 @@ class DisplayTopologyPreferenceTest {
         override val wallpaper: Bitmap?
             get() = systemWallpaper!!
 
+        override val densityDpi = DisplayMetrics.DENSITY_DEFAULT
+
         override fun registerTopologyListener(listener: Consumer<DisplayTopology>) {
             if (topologyListener != null) {
                 throw IllegalStateException(

tests/robotests/src/com/android/settings/connecteddevice/display/TopologyScaleTest.kt

@@ -35,7 +35,7 @@ class TopologyScaleTest {
     fun oneDisplay4to3Aspect() {
         val scale = TopologyScale(
                 /* paneWidth= */ 640, minPaneHeight = 0f,
-                minEdgeLength = 48, maxBlockRatio = 0.05f,
+                minEdgeLength = 48f, maxBlockRatio = 0.05f,
                 listOf(RectF(0f, 0f, 640f, 480f)))
 
         // blockRatio is higher than 0.05 in order to make the smallest display edge (480 dp) 48dp
@@ -52,7 +52,7 @@ class TopologyScaleTest {
         // The paneHeight and origin coordinates are changed but the block ratio is the same.
         val taller = TopologyScale(
                 /* paneWidth= */ 640, minPaneHeight = 155.0f,
-                minEdgeLength = 48, maxBlockRatio = 0.05f,
+                minEdgeLength = 48f, maxBlockRatio = 0.05f,
                 listOf(RectF(0f, 0f, 640f, 480f)))
 
         assertEquals(
@@ -64,7 +64,7 @@ class TopologyScaleTest {
     fun twoUnalignedDisplays() {
         val scale = TopologyScale(
                 /* paneWidth= */ 300, minPaneHeight = 0f,
-                minEdgeLength = 48, maxBlockRatio = 0.05f,
+                minEdgeLength = 48f, maxBlockRatio = 0.05f,
                 listOf(RectF(0f, 0f, 1920f, 1200f), RectF(1920f, -300f, 3840f, 900f)))
 
         assertEquals(
@@ -80,7 +80,7 @@ class TopologyScaleTest {
     fun twoDisplaysBlockRatioBumpedForGarSizeMinimumHorizontal() {
         val scale = TopologyScale(
                 /* paneWidth= */ 192, minPaneHeight = 0f,
-                minEdgeLength = 48, maxBlockRatio = 0.05f,
+                minEdgeLength = 48f, maxBlockRatio = 0.05f,
                 listOf(RectF(0f, 0f, 240f, 320f), RectF(-240f, -320f, 0f, 0f)))
 
         // blockRatio is higher than 0.05 in order to make the smallest display edge (240 dp) 48dp
@@ -98,7 +98,7 @@ class TopologyScaleTest {
     fun paneVerticalPaddingLimitedByTallestDisplay() {
         val scale = TopologyScale(
                 /* paneWidth= */ 300, minPaneHeight = 0f,
-                minEdgeLength = 48, maxBlockRatio = 0.05f,
+                minEdgeLength = 48f, maxBlockRatio = 0.05f,
                 listOf(
                         RectF(0f, 0f, 640f, 480f),
                         RectF(0f, 480f, 640f, 960f),
@@ -118,7 +118,7 @@ class TopologyScaleTest {
     fun limitedByCustomMaxBlockRatio() {
         val scale = TopologyScale(
                 /* paneWidth= */ 300, minPaneHeight = 0f,
-                minEdgeLength = 24, maxBlockRatio = 0.12f,
+                minEdgeLength = 24f, maxBlockRatio = 0.12f,
                 listOf(
                         RectF(0f, 0f, 640f, 480f),
                         RectF(0f, 480f, 640f, 960f)))
@@ -135,7 +135,7 @@ class TopologyScaleTest {
         // minBlockEdgeLength/minDisplayEdgeLength = 80/480 = 1/6, so the block ratio will be 1/6
         val scale = TopologyScale(
                 /* paneWidth= */ 300, minPaneHeight = 0f,
-                minEdgeLength = 80, maxBlockRatio = 0.05f,
+                minEdgeLength = 80f, maxBlockRatio = 0.05f,
                 listOf(
                         RectF(0f, 0f, 640f, 480f),
                         RectF(0f, 480f, 640f, 960f)))