Android/InputOverlayPointer: Don't assume surface covers whole screen

This assumption is false both in portrait mode (where it only
covers the top half of the screen) and when using two apps at once.

Fixes https://bugs.dolphin-emu.org/issues/12307.

3 files changed, 59 insertions, 68 deletions

diff --git a/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/fragments/EmulationFragment.java b/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/fragments/EmulationFragment.java
index 43fc64baa4..fa174c602c 100644
--- a/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/fragments/EmulationFragment.java
+++ b/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/fragments/EmulationFragment.java
@@ -1,6 +1,7 @@
 package org.dolphinemu.dolphinemu.fragments;
 
 import android.content.Context;
+import android.graphics.Rect;
 import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.Surface;
@@ -93,6 +94,15 @@ public final class EmulationFragment extends Fragment implements SurfaceHolder.C
       doneButton.setOnClickListener(v -> stopConfiguringControls());
     }
 
+    contents.post(() ->
+    {
+      int overlayX = mInputOverlay.getLeft();
+      int overlayY = mInputOverlay.getTop();
+      mInputOverlay.setSurfacePosition(new Rect(
+              surfaceView.getLeft() - overlayX, surfaceView.getTop() - overlayY,
+              surfaceView.getRight() - overlayX, surfaceView.getBottom() - overlayY));
+    });
+
     // The new Surface created here will get passed to the native code via onSurfaceChanged.
 
     return contents;
diff --git a/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/overlay/InputOverlay.java b/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/overlay/InputOverlay.java
index 49748166bd..fe37981ab5 100644
--- a/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/overlay/InputOverlay.java
+++ b/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/overlay/InputOverlay.java
@@ -60,7 +60,9 @@ public final class InputOverlay extends SurfaceView implements OnTouchListener
   private final Set<InputOverlayDrawableButton> overlayButtons = new HashSet<>();
   private final Set<InputOverlayDrawableDpad> overlayDpads = new HashSet<>();
   private final Set<InputOverlayDrawableJoystick> overlayJoysticks = new HashSet<>();
-  private InputOverlayPointer overlayPointer;
+  private InputOverlayPointer overlayPointer = null;
+
+  private Rect mSurfacePosition = null;
 
   private boolean mIsFirstRun = true;
   private boolean mIsInEditMode = false;
@@ -125,19 +127,7 @@ public final class InputOverlay extends SurfaceView implements OnTouchListener
 
     // Load the controls if we can. If not, EmulationActivity has to do it later.
     if (NativeLibrary.IsGameMetadataValid())
-    {
-      if (NativeLibrary.IsRunning())
-      {
-        // We would've needed a refreshControls call here in addition to the initTouchPointer call
-        // if it wasn't for initTouchPointer calling refreshControls.
-        initTouchPointer();
-      }
-      else
-      {
-        // We can't call initTouchPointer yet because it needs the aspect ratio of the running game.
-        refreshControls();
-      }
-    }
+      refreshControls();
 
     // Set the on touch listener.
     setOnTouchListener(this);
@@ -149,24 +139,33 @@ public final class InputOverlay extends SurfaceView implements OnTouchListener
     requestFocus();
   }
 
+  public void setSurfacePosition(Rect rect)
+  {
+    mSurfacePosition = rect;
+    initTouchPointer();
+  }
+
   public void initTouchPointer()
   {
-    // Refresh before starting the pointer
-    refreshControls();
+    // Check if we have all the data we need yet
+    boolean aspectRatioAvailable = NativeLibrary.IsRunning() && !NativeLibrary.IsBooting();
+    if (!aspectRatioAvailable || mSurfacePosition == null)
+      return;
 
-    if (NativeLibrary.IsEmulatingWii())
-    {
-      int doubleTapButton = IntSetting.MAIN_DOUBLE_TAP_BUTTON.getIntGlobal();
+    // Check if there's any point in running the pointer code
+    if (!NativeLibrary.IsEmulatingWii())
+      return;
 
-      if (mPreferences.getInt("wiiController", OVERLAY_WIIMOTE_NUNCHUK) !=
-              InputOverlay.OVERLAY_WIIMOTE_CLASSIC &&
-              doubleTapButton == InputOverlayPointer.DOUBLE_TAP_CLASSIC_A)
-      {
-        doubleTapButton = InputOverlayPointer.DOUBLE_TAP_A;
-      }
+    int doubleTapButton = IntSetting.MAIN_DOUBLE_TAP_BUTTON.getIntGlobal();
 
-      overlayPointer = new InputOverlayPointer(this.getContext(), doubleTapButton);
+    if (mPreferences.getInt("wiiController", OVERLAY_WIIMOTE_NUNCHUK) !=
+            InputOverlay.OVERLAY_WIIMOTE_CLASSIC &&
+            doubleTapButton == InputOverlayPointer.DOUBLE_TAP_CLASSIC_A)
+    {
+      doubleTapButton = InputOverlayPointer.DOUBLE_TAP_A;
     }
+
+    overlayPointer = new InputOverlayPointer(mSurfacePosition, doubleTapButton);
   }
 
   @Override
diff --git a/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/overlay/InputOverlayPointer.java b/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/overlay/InputOverlayPointer.java
index c56853cf88..cd3653d318 100644
--- a/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/overlay/InputOverlayPointer.java
+++ b/Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/overlay/InputOverlayPointer.java
@@ -1,10 +1,7 @@
 package org.dolphinemu.dolphinemu.overlay;
 
-import android.app.Activity;
-import android.content.Context;
+import android.graphics.Rect;
 import android.os.Handler;
-import android.util.DisplayMetrics;
-import android.view.Display;
 import android.view.MotionEvent;
 
 import org.dolphinemu.dolphinemu.NativeLibrary;
@@ -20,10 +17,11 @@ public class InputOverlayPointer
 
   private final float[] axes = {0f, 0f};
 
-  private float maxHeight;
-  private float maxWidth;
-  private float aspectAdjusted;
-  private boolean xAdjusted;
+  private float mGameCenterX;
+  private float mGameCenterY;
+  private float mGameWidthHalfInv;
+  private float mGameHeightHalfInv;
+
   private boolean doubleTap = false;
   private int doubleTapButton;
   private int trackId = -1;
@@ -38,39 +36,33 @@ public class InputOverlayPointer
     DOUBLE_TAP_OPTIONS.add(NativeLibrary.ButtonType.CLASSIC_BUTTON_A);
   }
 
-  public InputOverlayPointer(Context context, int button)
+  public InputOverlayPointer(Rect surfacePosition, int button)
   {
-    Display display = ((Activity) context).getWindowManager().getDefaultDisplay();
-    DisplayMetrics outMetrics = new DisplayMetrics();
-    display.getMetrics(outMetrics);
     doubleTapButton = button;
 
-    Integer y = outMetrics.heightPixels;
-    Integer x = outMetrics.widthPixels;
+    mGameCenterX = (surfacePosition.left + surfacePosition.right) / 2.0f;
+    mGameCenterY = (surfacePosition.top + surfacePosition.bottom) / 2.0f;
+
+    float gameWidth = surfacePosition.right - surfacePosition.left;
+    float gameHeight = surfacePosition.bottom - surfacePosition.top;
 
     // Adjusting for device's black bars.
-    float deviceAR = (float) x / y;
+    float surfaceAR = gameWidth / gameHeight;
     float gameAR = NativeLibrary.GetGameAspectRatio();
-    aspectAdjusted = gameAR / deviceAR;
 
-    if (gameAR <= deviceAR) // Black bars on left/right
+    if (gameAR <= surfaceAR)
     {
-      xAdjusted = true;
-      Integer gameX = Math.round((float) y * gameAR);
-      Integer buffer = (x - gameX);
-
-      maxWidth = (float) (x - buffer) / 2;
-      maxHeight = (float) y / 2;
+      // Black bars on left/right
+      gameWidth = gameHeight * gameAR;
     }
-    else // Bars on top/bottom
+    else
     {
-      xAdjusted = false;
-      Integer gameY = Math.round((float) x / gameAR);
-      Integer buffer = (y - gameY);
-
-      maxWidth = (float) x / 2;
-      maxHeight = (float) (y - buffer) / 2;
+      // Black bars on top/bottom
+      gameHeight = gameWidth / gameAR;
     }
+
+    mGameWidthHalfInv = 1.0f / (gameWidth * 0.5f);
+    mGameHeightHalfInv = 1.0f / (gameHeight * 0.5f);
   }
 
   public void onTouch(MotionEvent event)
@@ -94,18 +86,8 @@ public class InputOverlayPointer
     if (trackId == -1)
       return;
 
-    int x = (int) event.getX(event.findPointerIndex(trackId));
-    int y = (int) event.getY(event.findPointerIndex(trackId));
-    if (xAdjusted)
-    {
-      axes[0] = (y - maxHeight) / maxHeight;
-      axes[1] = ((x * aspectAdjusted) - maxWidth) / maxWidth;
-    }
-    else
-    {
-      axes[0] = ((y * aspectAdjusted) - maxHeight) / maxHeight;
-      axes[1] = (x - maxWidth) / maxWidth;
-    }
+    axes[0] = (event.getY(event.findPointerIndex(trackId)) - mGameCenterY) * mGameHeightHalfInv;
+    axes[1] = (event.getX(event.findPointerIndex(trackId)) - mGameCenterX) * mGameWidthHalfInv;
   }
 
   private void touchPress()