Changeset 286810 in webkit

Timestamp:

Dec 9, 2021, 3:19:32 PM (5 years ago)

Author:

Alan Coon

Message:

Cherry-pick r286805. rdar://problem/86291413

Momentum Generator: Scroll tail hiccup only when scrolling up on 60Hz displays
​https://bugs.webkit.org/show_bug.cgi?id=234104
<rdar://problem/86291413>

Reviewed by Simon Fraser.

• WebProcess/WebPage/MomentumEventDispatcher.cpp: (WebKit::MomentumEventDispatcher::equalizeTailGaps): Sort in the correct direction based on the sign of the first delta...

git-svn-id: ​https://svn.webkit.org/repository/webkit/trunk@286805 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Location:

branches/safari-612.4.2.1-branch/Source/WebKit

Files:

• ChangeLog (modified) (1 diff)
• WebProcess/WebPage/MomentumEventDispatcher.cpp (modified) (2 diffs)

branches/safari-612.4.2.1-branch/Source/WebKit/ChangeLog

@@ +1 @@
+2021-12-09  Alan Coon  <alancoon@apple.com>
+
+        Cherry-pick r286805. rdar://problem/86291413
+
+    Momentum Generator: Scroll tail hiccup only when scrolling up on 60Hz displays
+    https://bugs.webkit.org/show_bug.cgi?id=234104
+    <rdar://problem/86291413>
+    
+    Reviewed by Simon Fraser.
+    
+    * WebProcess/WebPage/MomentumEventDispatcher.cpp:
+    (WebKit::MomentumEventDispatcher::equalizeTailGaps):
+    Sort in the correct direction based on the sign of the first delta...
+    
+    
+    git-svn-id: https://svn.webkit.org/repository/webkit/trunk@286805 268f45cc-cd09-0410-ab3c-d52691b4dbfc
+
+    2021-12-09  Tim Horton  <timothy_horton@apple.com>
+
+            Momentum Generator: Scroll tail hiccup only when scrolling up on 60Hz displays
+            https://bugs.webkit.org/show_bug.cgi?id=234104
+            <rdar://problem/86291413>
+
+            Reviewed by Simon Fraser.
+
+            * WebProcess/WebPage/MomentumEventDispatcher.cpp:
+            (WebKit::MomentumEventDispatcher::equalizeTailGaps):
+            Sort in the correct direction based on the sign of the first delta...
+
 2021-12-08  Alan Coon  <alancoon@apple.com>
 

branches/safari-612.4.2.1-branch/Source/WebKit/WebProcess/WebPage/MomentumEventDispatcher.cpp

@@ -415 +415 @@
     auto& table = m_currentGesture.tailDeltaTable;
     size_t initialTableSize = table.size();
+    if (!initialTableSize)
+        return;
 
     enum Axis { Horizontal, Vertical };
@@ -430 +432 @@
             firstZeroIndex[Vertical] = i;
     }
-    
-    if (auto index = firstZeroIndex[Horizontal])
-        std::sort(deltas[Horizontal].begin(), std::next(deltas[Horizontal].begin(), index));
-    if (auto index = firstZeroIndex[Vertical])
-        std::sort(deltas[Vertical].begin(), std::next(deltas[Vertical].begin(), index));
+
+    auto sortDeltas = [&] (Axis axis) {
+        if (!firstZeroIndex[axis])
+            return;
+
+        if (deltas[axis][0] > 0)
+            std::sort(deltas[axis].begin(), std::next(deltas[axis].begin(), firstZeroIndex[axis]), std::greater<float>());
+        else
+            std::sort(deltas[axis].begin(), std::next(deltas[axis].begin(), firstZeroIndex[axis]), std::less<float>());
+    };
+
+    sortDeltas(Horizontal);
+    sortDeltas(Vertical);
 
     // GapSize is a count of contiguous frames with zero deltas.