Changeset 152214 in webkit

Timestamp:

Jun 29, 2013, 1:27:08 PM (12 years ago)

Author:

Simon Fraser

Message:

Avoid calling into Objective-C every time we get the scrollbar width
​https://bugs.webkit.org/show_bug.cgi?id=118216

Reviewed by Geoffrey Garen.

Profiling shows that calling Scrollbar::isOverlayScrollbar() is somewhat
expensive, because it calls down into Objective-C. Fix by caching in
ScrollbarThemeMac whether we're using overlay scrollbars. We update this
cache on creation, and when preferences change; ScrollAnimatorMac::updateScrollerStyle()
is the function that gets called when the user changes the setting in System Preferences.

• platform/ScrollbarTheme.h:

(WebCore::ScrollbarTheme::usesOverlayScrollbarsChanged):

• platform/mac/ScrollAnimatorMac.mm:

(WebCore::ScrollAnimatorMac::updateScrollerStyle):

• platform/mac/ScrollbarThemeMac.h:
• platform/mac/ScrollbarThemeMac.mm:

(WebCore::ScrollbarThemeMac::preferencesChanged):
(WebCore::ScrollbarThemeMac::usesOverlayScrollbars):
(WebCore::ScrollbarThemeMac::usesOverlayScrollbarsChanged):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/ScrollbarTheme.h (modified) (1 diff)
• platform/mac/ScrollAnimatorMac.mm (modified) (1 diff)
• platform/mac/ScrollbarThemeMac.h (modified) (1 diff)
• platform/mac/ScrollbarThemeMac.mm (modified) (3 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2013-06-29  Simon Fraser  <simon.fraser@apple.com>
+
+        Avoid calling into Objective-C every time we get the scrollbar width
+        https://bugs.webkit.org/show_bug.cgi?id=118216
+
+        Reviewed by Geoffrey Garen.
+
+        Profiling shows that calling Scrollbar::isOverlayScrollbar() is somewhat
+        expensive, because it calls down into Objective-C. Fix by caching in
+        ScrollbarThemeMac whether we're using overlay scrollbars. We update this
+        cache on creation, and when preferences change; ScrollAnimatorMac::updateScrollerStyle()
+        is the function that gets called when the user changes the setting in System Preferences.
+
+        * platform/ScrollbarTheme.h:
+        (WebCore::ScrollbarTheme::usesOverlayScrollbarsChanged):
+        * platform/mac/ScrollAnimatorMac.mm:
+        (WebCore::ScrollAnimatorMac::updateScrollerStyle):
+        * platform/mac/ScrollbarThemeMac.h:
+        * platform/mac/ScrollbarThemeMac.mm:
+        (WebCore::ScrollbarThemeMac::preferencesChanged):
+        (WebCore::ScrollbarThemeMac::usesOverlayScrollbars):
+        (WebCore::ScrollbarThemeMac::usesOverlayScrollbarsChanged):
+
 2013-06-29  Simon Fraser  <simon.fraser@apple.com>
 

trunk/Source/WebCore/platform/ScrollbarTheme.h

@@ -58 +58 @@
     virtual bool supportsControlTints() const { return false; }
     virtual bool usesOverlayScrollbars() const { return false; }
+    virtual void usesOverlayScrollbarsChanged() { }
     virtual void updateScrollbarOverlayStyle(ScrollbarThemeClient*) { }
 

trunk/Source/WebCore/platform/mac/ScrollAnimatorMac.mm

@@ -1213 +1213 @@
         return;
     }
+    
+    macTheme->usesOverlayScrollbarsChanged();
 
     NSScrollerStyle newStyle = [m_scrollbarPainterController.get() scrollerStyle];

trunk/Source/WebCore/platform/mac/ScrollbarThemeMac.h

@@ -48 +48 @@
     virtual bool supportsControlTints() const { return true; }
     virtual bool usesOverlayScrollbars() const;
+    virtual void usesOverlayScrollbarsChanged() OVERRIDE;
     virtual void updateScrollbarOverlayStyle(ScrollbarThemeClient*);
 

trunk/Source/WebCore/platform/mac/ScrollbarThemeMac.mm

@@ -134 +134 @@
 static float gAutoscrollButtonDelay = 0.05f;
 static bool gJumpOnTrackClick = false;
+static bool gUsesOverlayScrollbars = false;
 
 static ScrollbarButtonsPlacement gButtonPlacement = ScrollbarButtonsDoubleEnd;
@@ -227 +228 @@
     gAutoscrollButtonDelay = [defaults floatForKey:@"NSScrollerButtonPeriod"];
     gJumpOnTrackClick = [defaults boolForKey:@"AppleScrollerPagingBehavior"];
+    usesOverlayScrollbarsChanged();
 }
 
@@ -242 +244 @@
 bool ScrollbarThemeMac::usesOverlayScrollbars() const
 {
+    return gUsesOverlayScrollbars;
+}
+
+void ScrollbarThemeMac::usesOverlayScrollbarsChanged()
+{
     if (isScrollbarOverlayAPIAvailable())
-        return recommendedScrollerStyle() == NSScrollerStyleOverlay;
+        gUsesOverlayScrollbars = recommendedScrollerStyle() == NSScrollerStyleOverlay;
     else
-        return false;
+        gUsesOverlayScrollbars = false;
 }