From dcecfcf76f300652fa6faed47158276cc070e332 Mon Sep 17 00:00:00 2001
From: Jason Chang <jasonsfchang@google.com>
Date: Mon, 12 Apr 2021 16:40:56 +0800
Subject: Fix One Handed Feedback gesture's animations are quite jarring

To provide a new Interpolator formula for One-Handed transition
animation.

Bug: 178355565
Test: manual
Test: atest WMShellUnitTests
Change-Id: I78d998569618dc52c8b6fce6cb4a71f13ad01ba8
---
 libs/WindowManager/Shell/res/values/config.xml     |  2 +-
 .../onehanded/OneHandedAnimationController.java    | 22 +++++++++++++++++-----
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/libs/WindowManager/Shell/res/values/config.xml b/libs/WindowManager/Shell/res/values/config.xml
index 6698a01dc159..a138fee32550 100644
--- a/libs/WindowManager/Shell/res/values/config.xml
+++ b/libs/WindowManager/Shell/res/values/config.xml
@@ -40,7 +40,7 @@
     <integer name="long_press_dock_anim_duration">250</integer>
 
     <!-- Animation duration for translating of one handed when trigger / dismiss. -->
-    <integer name="config_one_handed_translate_animation_duration">300</integer>
+    <integer name="config_one_handed_translate_animation_duration">800</integer>
 
     <!-- One handed mode default offset % of display size -->
     <fraction name="config_one_handed_offset">40%</fraction>
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/onehanded/OneHandedAnimationController.java b/libs/WindowManager/Shell/src/com/android/wm/shell/onehanded/OneHandedAnimationController.java
index 125e322974bf..25dd3ca57b92 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/onehanded/OneHandedAnimationController.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/onehanded/OneHandedAnimationController.java
@@ -22,8 +22,7 @@ import android.annotation.IntDef;
 import android.content.Context;
 import android.graphics.Rect;
 import android.view.SurfaceControl;
-import android.view.animation.Interpolator;
-import android.view.animation.OvershootInterpolator;
+import android.view.animation.BaseInterpolator;
 import android.window.WindowContainerToken;
 
 import androidx.annotation.VisibleForTesting;
@@ -54,7 +53,7 @@ public class OneHandedAnimationController {
     public @interface TransitionDirection {
     }
 
-    private final Interpolator mOvershootInterpolator;
+    private final OneHandedInterpolator mInterpolator;
     private final OneHandedSurfaceTransactionHelper mSurfaceTransactionHelper;
     private final HashMap<WindowContainerToken, OneHandedTransitionAnimator> mAnimatorMap =
             new HashMap<>();
@@ -64,7 +63,7 @@ public class OneHandedAnimationController {
      */
     public OneHandedAnimationController(Context context) {
         mSurfaceTransactionHelper = new OneHandedSurfaceTransactionHelper(context);
-        mOvershootInterpolator = new OvershootInterpolator();
+        mInterpolator = new OneHandedInterpolator();
     }
 
     @SuppressWarnings("unchecked")
@@ -102,7 +101,7 @@ public class OneHandedAnimationController {
     OneHandedTransitionAnimator setupOneHandedTransitionAnimator(
             OneHandedTransitionAnimator animator) {
         animator.setSurfaceTransactionHelper(mSurfaceTransactionHelper);
-        animator.setInterpolator(mOvershootInterpolator);
+        animator.setInterpolator(mInterpolator);
         animator.setFloatValues(FRACTION_START, FRACTION_END);
         return animator;
     }
@@ -112,6 +111,8 @@ public class OneHandedAnimationController {
      *
      * @param <T> Type of property to animate, either offset (float)
      */
+    // TODO: Refactoring to use SpringAnimation and DynamicAnimation instead of using ValueAnimator
+    //  to implement One-Handed transition animation. (b/185129031)
     public abstract static class OneHandedTransitionAnimator<T> extends ValueAnimator implements
             ValueAnimator.AnimatorUpdateListener,
             ValueAnimator.AnimatorListener {
@@ -297,4 +298,15 @@ public class OneHandedAnimationController {
             };
         }
     }
+
+    /**
+     * An Interpolator for One-Handed transition animation.
+     */
+    public class OneHandedInterpolator extends BaseInterpolator {
+        @Override
+        public float getInterpolation(float input) {
+            return (float) (Math.pow(2, -10 * input) * Math.sin(((input - 4.0f) / 4.0f)
+                    * (2.0f * Math.PI) / 4.0f) + 1);
+        }
+    }
 }
-- 
cgit v1.2.3-59-g8ed1b