Merge changes from topic "am-cf9638ae-d2ec-4b5a-94ac-d1ce047249a4" into ub-launcher3-master

* changes:
  [automerger] Swipe up overshoot always plays am: cc3755da6e
  Swipe up overshoot always plays

3 files changed, 134 insertions, 37 deletions

diff --git a/quickstep/src/com/android/quickstep/LongSwipeHelper.java b/quickstep/src/com/android/quickstep/LongSwipeHelper.java
index 078509330..491cbb3d2 100644
--- a/quickstep/src/com/android/quickstep/LongSwipeHelper.java
+++ b/quickstep/src/com/android/quickstep/LongSwipeHelper.java
@@ -20,17 +20,22 @@ import static com.android.launcher3.LauncherState.ALL_APPS;
 import static com.android.launcher3.LauncherState.OVERVIEW;
 import static com.android.launcher3.anim.Interpolators.DEACCEL;
 import static com.android.quickstep.WindowTransformSwipeHandler.MAX_SWIPE_DURATION;
+import static com.android.quickstep.WindowTransformSwipeHandler.MIN_OVERSHOOT_DURATION;
 
 import android.animation.ValueAnimator;
+import android.view.animation.Interpolator;
 
 import com.android.launcher3.Launcher;
 import com.android.launcher3.LauncherAnimUtils;
 import com.android.launcher3.LauncherStateManager;
 import com.android.launcher3.R;
+import com.android.launcher3.Utilities;
 import com.android.launcher3.allapps.AllAppsTransitionController;
 import com.android.launcher3.allapps.DiscoveryBounce;
 import com.android.launcher3.anim.AnimatorPlaybackController;
 import com.android.launcher3.anim.AnimatorSetBuilder;
+import com.android.launcher3.anim.Interpolators;
+import com.android.launcher3.anim.Interpolators.OvershootParams;
 import com.android.launcher3.uioverrides.PortraitStatesTouchController;
 import com.android.launcher3.userevent.nano.LauncherLogProto.Action.Direction;
 import com.android.launcher3.userevent.nano.LauncherLogProto.Action.Touch;
@@ -89,7 +94,9 @@ public class LongSwipeHelper {
     }
 
     public void end(float velocity, boolean isFling, Runnable callback) {
+        float velocityPxPerMs = velocity / 1000;
         long duration = MAX_SWIPE_DURATION;
+        Interpolator interpolator = DEACCEL;
 
         final float currentFraction = mAnimator.getProgressFraction();
         final boolean toAllApps;
@@ -107,6 +114,17 @@ public class LongSwipeHelper {
             long expectedDuration = Math.abs(Math.round((endProgress - currentFraction)
                     * MAX_SWIPE_DURATION * SWIPE_DURATION_MULTIPLIER));
             duration = Math.min(MAX_SWIPE_DURATION, expectedDuration);
+
+            if (blockedFling && !toAllApps) {
+                Interpolators.OvershootParams overshoot = new OvershootParams(currentFraction,
+                        currentFraction, endProgress, velocityPxPerMs, (int) mMaxSwipeDistance);
+                duration = (overshoot.duration + duration)
+                        * LauncherAnimUtils.blockedFlingDurationFactor(0);
+                duration = Utilities.boundToRange(duration, MIN_OVERSHOOT_DURATION,
+                        MAX_SWIPE_DURATION);
+                interpolator = overshoot.interpolator;
+                endProgress = overshoot.end;
+            }
         } else {
             toAllApps = velocity < 0;
             endProgress = toAllApps ? 1 : 0;
@@ -119,18 +137,16 @@ public class LongSwipeHelper {
                 // we want the page's snap velocity to approximately match the velocity at
                 // which the user flings, so we scale the duration by a value near to the
                 // derivative of the scroll interpolator at zero, ie. 2.
-                long baseDuration = Math.round(1000 * Math.abs(distanceToTravel / velocity));
+                long baseDuration = Math.round(Math.abs(distanceToTravel / velocityPxPerMs));
                 duration = Math.min(MAX_SWIPE_DURATION, 2 * baseDuration);
             }
         }
 
-        if (blockedFling && !toAllApps) {
-            duration *= LauncherAnimUtils.blockedFlingDurationFactor(0);
-        }
         final boolean finalIsFling = isFling;
         mAnimator.setEndAction(() -> onSwipeAnimationComplete(toAllApps, finalIsFling, callback));
+
         ValueAnimator animator = mAnimator.getAnimationPlayer();
-        animator.setDuration(duration).setInterpolator(DEACCEL);
+        animator.setDuration(duration).setInterpolator(interpolator);
         animator.setFloatValues(currentFraction, endProgress);
         animator.start();
     }
diff --git a/quickstep/src/com/android/quickstep/WindowTransformSwipeHandler.java b/quickstep/src/com/android/quickstep/WindowTransformSwipeHandler.java
index ff3137d44..15ff19e26 100644
--- a/quickstep/src/com/android/quickstep/WindowTransformSwipeHandler.java
+++ b/quickstep/src/com/android/quickstep/WindowTransformSwipeHandler.java
@@ -21,6 +21,7 @@ import static com.android.launcher3.Utilities.SINGLE_FRAME_MS;
 import static com.android.launcher3.Utilities.postAsyncCallback;
 import static com.android.launcher3.anim.Interpolators.DEACCEL;
 import static com.android.launcher3.anim.Interpolators.LINEAR;
+import static com.android.launcher3.anim.Interpolators.OVERSHOOT_1_2;
 import static com.android.quickstep.QuickScrubController.QUICK_SCRUB_FROM_APP_START_DURATION;
 import static com.android.quickstep.TouchConsumer.INTERACTION_NORMAL;
 import static com.android.quickstep.TouchConsumer.INTERACTION_QUICK_SCRUB;
@@ -163,6 +164,7 @@ public class WindowTransformSwipeHandler<T extends BaseDraggingActivity> {
 
     public static final long MAX_SWIPE_DURATION = 350;
     public static final long MIN_SWIPE_DURATION = 80;
+    public static final long MIN_OVERSHOOT_DURATION = 120;
 
     public static final float MIN_PROGRESS_FOR_OVERVIEW = 0.5f;
     private static final float SWIPE_DURATION_MULTIPLIER =
@@ -498,7 +500,8 @@ public class WindowTransformSwipeHandler<T extends BaseDraggingActivity> {
         setStateOnUiThread(STATE_QUICK_SCRUB_START | STATE_GESTURE_COMPLETED);
 
         // Start the window animation without waiting for launcher.
-        animateToProgress(mCurrentShift.value, 1f, QUICK_SCRUB_FROM_APP_START_DURATION, LINEAR);
+        animateToProgress(mCurrentShift.value, 1f, QUICK_SCRUB_FROM_APP_START_DURATION, LINEAR,
+                true /* goingToHome */);
     }
 
     private void shiftAnimationDestinationForQuickscrub() {
@@ -699,36 +702,46 @@ public class WindowTransformSwipeHandler<T extends BaseDraggingActivity> {
     private void handleNormalGestureEnd(float endVelocity, boolean isFling) {
         float velocityPxPerMs = endVelocity / 1000;
         long duration = MAX_SWIPE_DURATION;
-        final float endShift;
+        float currentShift = mCurrentShift.value;
+        final boolean goingToHome;
+        float endShift;
         final float startShift;
-        final Interpolator interpolator;
+        Interpolator interpolator = DEACCEL;
         if (!isFling) {
-            endShift = mCurrentShift.value >= MIN_PROGRESS_FOR_OVERVIEW && mGestureStarted ? 1 : 0;
-            long expectedDuration = Math.abs(Math.round((endShift - mCurrentShift.value)
+            goingToHome = currentShift >= MIN_PROGRESS_FOR_OVERVIEW && mGestureStarted;
+            endShift = goingToHome ? 1 : 0;
+            long expectedDuration = Math.abs(Math.round((endShift - currentShift)
                     * MAX_SWIPE_DURATION * SWIPE_DURATION_MULTIPLIER));
             duration = Math.min(MAX_SWIPE_DURATION, expectedDuration);
-            startShift = mCurrentShift.value;
-            interpolator = DEACCEL;
+            startShift = currentShift;
+            interpolator = goingToHome ? OVERSHOOT_1_2 : DEACCEL;
         } else {
-            endShift = endVelocity < 0 ? 1 : 0;
-            interpolator = endVelocity < 0
-                    ? Interpolators.overshootInterpolatorForVelocity(velocityPxPerMs, 2f)
-                    : DEACCEL;
+            goingToHome = endVelocity < 0;
+            endShift = goingToHome ? 1 : 0;
+            startShift = Utilities.boundToRange(currentShift - velocityPxPerMs
+                    * SINGLE_FRAME_MS / mTransitionDragLength, 0, 1);
             float minFlingVelocity = mContext.getResources()
                     .getDimension(R.dimen.quickstep_fling_min_velocity);
             if (Math.abs(endVelocity) > minFlingVelocity && mTransitionDragLength > 0) {
-                float distanceToTravel = (endShift - mCurrentShift.value) * mTransitionDragLength;
-
-                // we want the page's snap velocity to approximately match the velocity at
-                // which the user flings, so we scale the duration by a value near to the
-                // derivative of the scroll interpolator at zero, ie. 2.
-                long baseDuration = Math.round(Math.abs(distanceToTravel / velocityPxPerMs));
-                duration = Math.min(MAX_SWIPE_DURATION, 2 * baseDuration);
+                if (goingToHome) {
+                    Interpolators.OvershootParams overshoot = new Interpolators.OvershootParams(
+                            startShift, endShift, endShift, velocityPxPerMs, mTransitionDragLength);
+                    endShift = overshoot.end;
+                    interpolator = overshoot.interpolator;
+                    duration = Utilities.boundToRange(overshoot.duration, MIN_OVERSHOOT_DURATION,
+                            MAX_SWIPE_DURATION);
+                } else {
+                    float distanceToTravel = (endShift - currentShift) * mTransitionDragLength;
+
+                    // we want the page's snap velocity to approximately match the velocity at
+                    // which the user flings, so we scale the duration by a value near to the
+                    // derivative of the scroll interpolator at zero, ie. 2.
+                    long baseDuration = Math.round(Math.abs(distanceToTravel / velocityPxPerMs));
+                    duration = Math.min(MAX_SWIPE_DURATION, 2 * baseDuration);
+                }
             }
-            startShift = Utilities.boundToRange(mCurrentShift.value - velocityPxPerMs
-                    * SINGLE_FRAME_MS / (mTransitionDragLength), 0, 1);
         }
-        animateToProgress(startShift, endShift, duration, interpolator);
+        animateToProgress(startShift, endShift, duration, interpolator, goingToHome);
     }
 
     private void doLogGesture(boolean toLauncher) {
@@ -754,14 +767,14 @@ public class WindowTransformSwipeHandler<T extends BaseDraggingActivity> {
 
     /** Animates to the given progress, where 0 is the current app and 1 is overview. */
     private void animateToProgress(float start, float end, long duration,
-            Interpolator interpolator) {
+            Interpolator interpolator, boolean goingToHome) {
         mRecentsAnimationWrapper.runOnInit(() -> animateToProgressInternal(start, end, duration,
-                interpolator));
+                interpolator, goingToHome));
     }
 
     private void animateToProgressInternal(float start, float end, long duration,
-            Interpolator interpolator) {
-        mIsGoingToHome = Float.compare(end, 1) == 0;
+            Interpolator interpolator, boolean goingToHome) {
+        mIsGoingToHome = goingToHome;
         ObjectAnimator anim = mCurrentShift.animateToValue(start, end).setDuration(duration);
         anim.setInterpolator(interpolator);
         anim.addListener(new AnimationSuccessListener() {
diff --git a/src/com/android/launcher3/anim/Interpolators.java b/src/com/android/launcher3/anim/Interpolators.java
index a4cba4f62..3e01f7262 100644
--- a/src/com/android/launcher3/anim/Interpolators.java
+++ b/src/com/android/launcher3/anim/Interpolators.java
@@ -16,7 +16,10 @@
 
 package com.android.launcher3.anim;
 
+import static com.android.launcher3.Utilities.SINGLE_FRAME_MS;
+
 import android.graphics.Path;
+import android.view.animation.AccelerateDecelerateInterpolator;
 import android.view.animation.AccelerateInterpolator;
 import android.view.animation.DecelerateInterpolator;
 import android.view.animation.Interpolator;
@@ -45,6 +48,8 @@ public class Interpolators {
     public static final Interpolator DEACCEL_2_5 = new DecelerateInterpolator(2.5f);
     public static final Interpolator DEACCEL_3 = new DecelerateInterpolator(3f);
 
+    public static final Interpolator ACCEL_DEACCEL = new AccelerateDecelerateInterpolator();
+
     public static final Interpolator FAST_OUT_SLOW_IN = new PathInterpolator(0.4f, 0f, 0.2f, 1f);
 
     public static final Interpolator AGGRESSIVE_EASE = new PathInterpolator(0.2f, 0f, 0f, 1f);
@@ -118,17 +123,12 @@ public class Interpolators {
         return Math.abs(velocity) > FAST_FLING_PX_MS ? SCROLL : SCROLL_CUBIC;
     }
 
-    public static Interpolator overshootInterpolatorForVelocity(float velocity) {
-        return overshootInterpolatorForVelocity(velocity, 1f);
-    }
-
     /**
      * Create an OvershootInterpolator with tension directly related to the velocity (in px/ms).
      * @param velocity The start velocity of the animation we want to overshoot.
-     * @param dampFactor An optional factor to reduce the amount of tension (how far we overshoot).
      */
-    public static Interpolator overshootInterpolatorForVelocity(float velocity, float dampFactor) {
-        return new OvershootInterpolator(Math.min(Math.abs(velocity), 3f) / dampFactor);
+    public static Interpolator overshootInterpolatorForVelocity(float velocity) {
+        return new OvershootInterpolator(Math.min(Math.abs(velocity), 3f));
     }
 
     /**
@@ -160,4 +160,72 @@ public class Interpolators {
             float upperBound) {
         return t -> Utilities.mapRange(interpolator.getInterpolation(t), lowerBound, upperBound);
     }
+
+    /**
+     * Computes parameters necessary for an overshoot effect.
+     */
+    public static class OvershootParams {
+        public Interpolator interpolator;
+        public float start;
+        public float end;
+        public long duration;
+
+        /**
+         * Given the input params, sets OvershootParams variables to be used by the caller.
+         * @param startProgress The progress from 0 to 1 that the overshoot starts from.
+         * @param overshootPastProgress The progress from 0 to 1 where we overshoot past (should
+         *        either be equal to startProgress or endProgress, depending on if we want to
+         *        overshoot immediately or only once we reach the end).
+         * @param endProgress The final progress from 0 to 1 that we will settle to.
+         * @param velocityPxPerMs The initial velocity that causes this overshoot.
+         * @param totalDistancePx The distance against which progress is calculated.
+         */
+        public OvershootParams(float startProgress, float overshootPastProgress,
+                float endProgress, float velocityPxPerMs, int totalDistancePx) {
+            velocityPxPerMs = Math.abs(velocityPxPerMs);
+            start = startProgress;
+            int startPx = (int) (start * totalDistancePx);
+            // Overshoot by about half a frame.
+            float overshootBy = velocityPxPerMs * SINGLE_FRAME_MS / totalDistancePx / 2;
+            overshootBy = Utilities.boundToRange(overshootBy, 0.02f, 0.15f);
+            end = overshootPastProgress + overshootBy;
+            int endPx = (int) (end  * totalDistancePx);
+            int overshootDistance = endPx - startPx;
+            // Calculate deceleration necessary to reach overshoot distance.
+            // Formula: velocityFinal^2 = velocityInitial^2 + 2 * acceleration * distance
+            //          0 = v^2 + 2ad (velocityFinal == 0)
+            //          a = v^2 / -2d
+            float decelerationPxPerMs = velocityPxPerMs * velocityPxPerMs / (2 * overshootDistance);
+            // Calculate time necessary to reach peak of overshoot.
+            // Formula: acceleration = velocity / time
+            //          time = velocity / acceleration
+            duration = (long) (velocityPxPerMs / decelerationPxPerMs);
+
+            // Now that we're at the top of the overshoot, need to settle back to endProgress.
+            float settleDistance = end - endProgress;
+            int settleDistancePx = (int) (settleDistance * totalDistancePx);
+            // Calculate time necessary for the settle.
+            // Formula: distance = velocityInitial * time + 1/2 * acceleration * time^2
+            //          d = 1/2at^2 (velocityInitial = 0, since we just stopped at the top)
+            //          t = sqrt(2d/a)
+            // Above formula assumes constant acceleration. Since we use ACCEL_DEACCEL, we actually
+            // have acceleration to halfway then deceleration the rest. So the formula becomes:
+            //          t = sqrt(d/a) * 2 (half the distance for accel, half for deaccel)
+            long settleDuration = (long) Math.sqrt(settleDistancePx / decelerationPxPerMs) * 2;
+            // How much of the animation to devote to playing the overshoot (the rest is for settle).
+            float overshootFraction = (float) duration / (duration + settleDuration);
+            duration += settleDuration;
+            // Finally, create the interpolator, composed of two interpolators: an overshoot, which
+            // reaches end > 1, and then a settle to endProgress.
+            Interpolator overshoot = Interpolators.clampToProgress(DEACCEL, 0, overshootFraction);
+            // The settle starts at 1, where 1 is the top of the overshoot, and maps to a fraction
+            // such that final progress is endProgress. For example, if we overshot to 1.1 but want
+            // to end at 1, we need to map to 1/1.1.
+            Interpolator settle = Interpolators.clampToProgress(Interpolators.mapToProgress(
+                    ACCEL_DEACCEL, 1, (endProgress - start) / (end - start)), overshootFraction, 1);
+            interpolator = t -> t <= overshootFraction
+                    ? overshoot.getInterpolation(t)
+                    : settle.getInterpolation(t);
+        }
+    }
 }
\ No newline at end of file