Changeset 274853 in webkit

Timestamp:

Mar 23, 2021 1:52:12 AM (16 months ago)

Author:

commit-queue@webkit.org

Message:

No scrolling momentum with 'scroll-snap-type: x mandatory' if the scroller scrolls vertically
​https://bugs.webkit.org/show_bug.cgi?id=213571
<rdar://problem/64715507>

Patch by Martin Robinson <​mrobinson@igalia.com> on 2021-03-23
Reviewed by Simon Fraser.

Source/WebCore:

When handling momentum scrolling for scroll containers that snap, use the
predicted momentum scroll destination for axes that do not snap. Using
the initial scroll offset here was causing momentum scrolling in these axes
to end prematurely.

Test: tiled-drawing/scrolling/scroll-snap/scroll-snap-momentum-in-non-snapping-axis.html

• platform/ScrollSnapAnimatorState.cpp:

(WebCore::ScrollSnapAnimatorState::targetOffsetForStartOffset const): Use the predicted
scroll offset. Even though the startOffset parameter is no longer used, do not remove
it because it will be used in the fix for ​https://bugs.webkit.org/show_bug.cgi?id=223406.

LayoutTests:

• tiled-drawing/scrolling/scroll-snap/scroll-snap-momentum-in-non-snapping-axis-expected.txt: Added.
• tiled-drawing/scrolling/scroll-snap/scroll-snap-momentum-in-non-snapping-axis.html: Added.

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/tiled-drawing/scrolling/scroll-snap/scroll-snap-momentum-in-non-snapping-axis-expected.txt (added)
• LayoutTests/tiled-drawing/scrolling/scroll-snap/scroll-snap-momentum-in-non-snapping-axis.html (added)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/platform/ScrollSnapAnimatorState.cpp (modified) (1 diff)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2021-03-23  Martin Robinson  <mrobinson@igalia.com>
+
+        No scrolling momentum with 'scroll-snap-type: x mandatory' if the scroller scrolls vertically
+        https://bugs.webkit.org/show_bug.cgi?id=213571
+        <rdar://problem/64715507>
+
+        Reviewed by Simon Fraser.
+
+        * tiled-drawing/scrolling/scroll-snap/scroll-snap-momentum-in-non-snapping-axis-expected.txt: Added.
+        * tiled-drawing/scrolling/scroll-snap/scroll-snap-momentum-in-non-snapping-axis.html: Added.
+
 2021-03-23  Said Abou-Hallawa  <said@apple.com>
 

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2021-03-23  Martin Robinson  <mrobinson@igalia.com>
+
+        No scrolling momentum with 'scroll-snap-type: x mandatory' if the scroller scrolls vertically
+        https://bugs.webkit.org/show_bug.cgi?id=213571
+        <rdar://problem/64715507>
+
+        Reviewed by Simon Fraser.
+
+        When handling momentum scrolling for scroll containers that snap, use the
+        predicted momentum scroll destination for axes that do not snap. Using
+        the initial scroll offset here was causing momentum scrolling in these axes
+        to end prematurely.
+
+        Test: tiled-drawing/scrolling/scroll-snap/scroll-snap-momentum-in-non-snapping-axis.html
+
+        * platform/ScrollSnapAnimatorState.cpp:
+        (WebCore::ScrollSnapAnimatorState::targetOffsetForStartOffset const): Use the predicted
+        scroll offset. Even though the startOffset parameter is no longer used, do not remove
+        it because it will be used in the fix for https://bugs.webkit.org/show_bug.cgi?id=223406.
+
 2021-03-23  Said Abou-Hallawa  <said@apple.com>
 

trunk/Source/WebCore/platform/ScrollSnapAnimatorState.cpp

@@ -97 +97 @@
     if (snapOffsets.isEmpty()) {
         outActiveSnapIndex = invalidSnapOffsetIndex;
-        return clampTo<float>(startOffset, 0, maxScrollOffset);
+        return clampTo<float>(predictedOffset, 0, maxScrollOffset);
     }