Changeset 162354 in webkit

Timestamp:

Jan 20, 2014 9:21:26 AM (10 years ago)

Author:

Antti Koivisto

Message:

Update overlay scrollbars in single pass
​https://bugs.webkit.org/show_bug.cgi?id=127289

Reviewed by Anders Carlsson.

• platform/ScrollView.cpp:

(WebCore::ScrollView::updateScrollbars):

Multi-pass scrollbar resolution is only needed for traditional scrollbars. Overlay scrollbars don't affect layout.

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/ScrollView.cpp (modified) (2 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2014-01-20  Antti Koivisto  <antti@apple.com>
+
+        Update overlay scrollbars in single pass
+        https://bugs.webkit.org/show_bug.cgi?id=127289
+
+        Reviewed by Anders Carlsson.
+
+        * platform/ScrollView.cpp:
+        (WebCore::ScrollView::updateScrollbars):
+        
+            Multi-pass scrollbar resolution is only needed for traditional scrollbars. Overlay scrollbars don't affect layout.
+
 2014-01-20  Jochen Eisinger  <jochen@chromium.org>
 

trunk/Source/WebCore/platform/ScrollView.cpp

@@ -506 +506 @@
         return;
 
+    bool hasOverlayScrollbars = (!m_horizontalScrollbar || m_horizontalScrollbar->isOverlayScrollbar()) && (!m_verticalScrollbar || m_verticalScrollbar->isOverlayScrollbar());
+
     // If we came in here with the view already needing a layout, then go ahead and do that
     // first.  (This will be the common case, e.g., when the page changes due to window resizing for example).
     // This layout will not re-enter updateScrollbars and does not count towards our max layout pass total.
-    if (!m_scrollbarsSuppressed) {
+    if (!m_scrollbarsSuppressed && !hasOverlayScrollbars) {
         m_inUpdateScrollbars = true;
         visibleContentsResized();
@@ -549 +551 @@
         IntSize fullVisibleSize = visibleContentRect(IncludeScrollbars).size();
 
-        if (hScroll == ScrollbarAuto) {
+        if (hScroll == ScrollbarAuto)
             newHasHorizontalScrollbar = docSize.width() > visibleWidth();
-            if (newHasHorizontalScrollbar && !m_updateScrollbarsPass && docSize.width() <= fullVisibleSize.width() && docSize.height() <= fullVisibleSize.height())
+        if (vScroll == ScrollbarAuto)
+            newHasVerticalScrollbar = docSize.height() > visibleHeight();
+
+        bool needAnotherPass = false;
+        if (!hasOverlayScrollbars) {
+            // If we ever turn one scrollbar off, always turn the other one off too. Never ever
+            // try to both gain/lose a scrollbar in the same pass.
+            if (!m_updateScrollbarsPass && docSize.width() <= fullVisibleSize.width() && docSize.height() <= fullVisibleSize.height()) {
+                if (hScroll == ScrollbarAuto)
+                    newHasHorizontalScrollbar = false;
+                if (vScroll == ScrollbarAuto)
+                    newHasVerticalScrollbar = false;
+            }
+            if (!newHasHorizontalScrollbar && hasHorizontalScrollbar && vScroll != ScrollbarAlwaysOn) {
+                newHasVerticalScrollbar = false;
+                needAnotherPass = true;
+            }
+            if (!newHasVerticalScrollbar && hasVerticalScrollbar && hScroll != ScrollbarAlwaysOn) {
                 newHasHorizontalScrollbar = false;
-        }
-        if (vScroll == ScrollbarAuto) {
-            newHasVerticalScrollbar = docSize.height() > visibleHeight();
-            if (newHasVerticalScrollbar && !m_updateScrollbarsPass && docSize.width() <= fullVisibleSize.width() && docSize.height() <= fullVisibleSize.height())
-                newHasVerticalScrollbar = false;
-        }
-
-        // If we ever turn one scrollbar off, always turn the other one off too.  Never ever
-        // try to both gain/lose a scrollbar in the same pass.
-        bool needAnotherPass = false;
-        if (!newHasHorizontalScrollbar && hasHorizontalScrollbar && vScroll != ScrollbarAlwaysOn) {
-            newHasVerticalScrollbar = false;
-            needAnotherPass = true;
-        }
-
-        if (!newHasVerticalScrollbar && hasVerticalScrollbar && hScroll != ScrollbarAlwaysOn) {
-            newHasHorizontalScrollbar = false;
-            needAnotherPass = true;
+                needAnotherPass = true;
+            }
         }