Bug 1246290 - Add a pref to allow disabling APZ on documents which have scroll-linked effects. r=botond
authorKartikaya Gupta <kgupta@mozilla.com>
Sun, 03 Apr 2016 13:13:59 -0400
changeset 291517 224ef65456d2
parent 291516 110538d89648
child 291518 e76831655536
push id19656
push usergwagner@mozilla.com
push dateMon, 04 Apr 2016 13:43:23 +0000
treeherderb2g-inbound@e99061fde28a [default view] [failures only]
perfherder[talos] [build metrics] [platform microbench] (compared to previous push)
reviewersbotond
bugs1246290
milestone48.0a1
Bug 1246290 - Add a pref to allow disabling APZ on documents which have scroll-linked effects. r=botond MozReview-Commit-ID: HQkHUiEWaWc
gfx/layers/apz/src/AsyncPanZoomController.cpp
gfx/thebes/gfxPrefs.h
layout/base/nsLayoutUtils.cpp
modules/libpref/init/all.js
--- a/gfx/layers/apz/src/AsyncPanZoomController.cpp
+++ b/gfx/layers/apz/src/AsyncPanZoomController.cpp
@@ -151,16 +151,24 @@ using mozilla::gfx::PointTyped;
  * goes from y=0...1000 and the visible portion is y=250...750 then
  * we're far from checkerboarding. If we get to y=490...990 though then we're
  * only 10 pixels away from showing checkerboarding so we are probably in
  * a state where we can't keep up with scrolling. The danger zone prefs specify
  * how wide this margin is; in the above example a y-axis danger zone of 10
  * pixels would make us drop to low-res at y=490...990.\n
  * This value is in layer pixels.
  *
+ * \li\b apz.disable_for_scroll_linked_effects
+ * Setting this pref to true will disable APZ scrolling on documents where
+ * scroll-linked effects are detected. A scroll linked effect is detected if
+ * positioning or transform properties are updated inside a scroll event
+ * dispatch; we assume that such an update is in response to the scroll event
+ * and is therefore a scroll-linked effect which will be laggy with APZ
+ * scrolling.
+ *
  * \li\b apz.displayport_expiry_ms
  * While a scrollable frame is scrolling async, we set a displayport on it
  * to make sure it is layerized. However this takes up memory, so once the
  * scrolling stops we want to remove the displayport. This pref controls how
  * long after scrolling stops the displayport is removed. A value of 0 will
  * disable the expiry behavior entirely.
  * Units: milliseconds
  *
--- a/gfx/thebes/gfxPrefs.h
+++ b/gfx/thebes/gfxPrefs.h
@@ -143,16 +143,17 @@ private:
   DECL_GFX_PREF(Live, "apz.axis_lock.breakout_angle",          APZAxisBreakoutAngle, float, float(M_PI / 8.0) /* 22.5 degrees */);
   DECL_GFX_PREF(Live, "apz.axis_lock.breakout_threshold",      APZAxisBreakoutThreshold, float, 1.0f / 32.0f);
   DECL_GFX_PREF(Live, "apz.axis_lock.direct_pan_angle",        APZAllowedDirectPanAngle, float, float(M_PI / 3.0) /* 60 degrees */);
   DECL_GFX_PREF(Live, "apz.axis_lock.lock_angle",              APZAxisLockAngle, float, float(M_PI / 6.0) /* 30 degrees */);
   DECL_GFX_PREF(Live, "apz.axis_lock.mode",                    APZAxisLockMode, int32_t, 0);
   DECL_GFX_PREF(Live, "apz.content_response_timeout",          APZContentResponseTimeout, int32_t, 300);
   DECL_GFX_PREF(Live, "apz.danger_zone_x",                     APZDangerZoneX, int32_t, 50);
   DECL_GFX_PREF(Live, "apz.danger_zone_y",                     APZDangerZoneY, int32_t, 100);
+  DECL_GFX_PREF(Live, "apz.disable_for_scroll_linked_effects", APZDisableForScrollLinkedEffects, bool, false);
   DECL_GFX_PREF(Live, "apz.displayport_expiry_ms",             APZDisplayPortExpiryTime, uint32_t, 15000);
   DECL_GFX_PREF(Live, "apz.drag.enabled",                      APZDragEnabled, bool, false);
   DECL_GFX_PREF(Live, "apz.enlarge_displayport_when_clipped",  APZEnlargeDisplayPortWhenClipped, bool, false);
   DECL_GFX_PREF(Live, "apz.fling_accel_base_mult",             APZFlingAccelBaseMultiplier, float, 1.0f);
   DECL_GFX_PREF(Live, "apz.fling_accel_interval_ms",           APZFlingAccelInterval, int32_t, 500);
   DECL_GFX_PREF(Live, "apz.fling_accel_supplemental_mult",     APZFlingAccelSupplementalMultiplier, float, 1.0f);
   DECL_GFX_PREF(Once, "apz.fling_curve_function_x1",           APZCurveFunctionX1, float, 0.0f);
   DECL_GFX_PREF(Once, "apz.fling_curve_function_x2",           APZCurveFunctionX2, float, 1.0f);
--- a/layout/base/nsLayoutUtils.cpp
+++ b/layout/base/nsLayoutUtils.cpp
@@ -1056,16 +1056,26 @@ GetDisplayPortFromMarginsData(nsIContent
   nsRect expandedScrollableRect =
     nsLayoutUtils::CalculateExpandedScrollableRect(frame);
   result = result.MoveInsideAndClamp(expandedScrollableRect - scrollPos);
 
   return result;
 }
 
 static bool
+ShouldDisableApzForElement(nsIContent* aContent)
+{
+  if (gfxPrefs::APZDisableForScrollLinkedEffects() && aContent) {
+    nsIDocument* doc = aContent->GetComposedDoc();
+    return (doc && doc->HasScrollLinkedEffect());
+  }
+  return false;
+}
+
+static bool
 GetDisplayPortImpl(nsIContent* aContent, nsRect *aResult, float aMultiplier)
 {
   DisplayPortPropertyData* rectData =
     static_cast<DisplayPortPropertyData*>(aContent->GetProperty(nsGkAtoms::DisplayPort));
   DisplayPortMarginsPropertyData* marginsData =
     static_cast<DisplayPortMarginsPropertyData*>(aContent->GetProperty(nsGkAtoms::DisplayPortMargins));
 
   if (!rectData && !marginsData) {
@@ -1089,17 +1099,17 @@ GetDisplayPortImpl(nsIContent* aContent,
   }
 
   NS_ASSERTION((rectData == nullptr) != (marginsData == nullptr),
                "Only one of rectData or marginsData should be set!");
 
   nsRect result;
   if (rectData) {
     result = GetDisplayPortFromRectData(aContent, rectData, aMultiplier);
-  } else if (APZCCallbackHelper::IsDisplayportSuppressed()) {
+  } else if (APZCCallbackHelper::IsDisplayportSuppressed() || ShouldDisableApzForElement(aContent)) {
     DisplayPortMarginsPropertyData noMargins(ScreenMargin(), 1);
     result = GetDisplayPortFromMarginsData(aContent, &noMargins, aMultiplier);
   } else {
     result = GetDisplayPortFromMarginsData(aContent, marginsData, aMultiplier);
   }
 
   if (!gfxPrefs::LayersTilesEnabled()) {
     // Either we should have gotten a valid rect directly from the displayport
@@ -8796,16 +8806,20 @@ nsLayoutUtils::ComputeScrollMetadata(nsI
       nsStyleContext* backgroundStyle;
       if (nsCSSRendering::FindBackground(aScrollFrame, &backgroundStyle)) {
         metrics.SetBackgroundColor(Color::FromABGR(
           backgroundStyle->StyleBackground()->mBackgroundColor));
       }
     }
   }
 
+  if (ShouldDisableApzForElement(aContent)) {
+    metrics.SetForceDisableApz(true);
+  }
+
   return metadata;
 }
 
 /* static */ bool
 nsLayoutUtils::ContainsMetricsWithId(const Layer* aLayer, const ViewID& aScrollId)
 {
   for (uint32_t i = aLayer->GetScrollMetadataCount(); i > 0; i--) {
     if (aLayer->GetFrameMetrics(i-1).GetScrollId() == aScrollId) {
--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -562,16 +562,17 @@ pref("apz.axis_lock.mode", 0);
 pref("apz.axis_lock.lock_angle", "0.5235987");        // PI / 6 (30 degrees)
 pref("apz.axis_lock.breakout_threshold", "0.03125");  // 1/32 inches
 pref("apz.axis_lock.breakout_angle", "0.3926991");    // PI / 8 (22.5 degrees)
 pref("apz.axis_lock.direct_pan_angle", "1.047197");   // PI / 3 (60 degrees)
 pref("apz.content_response_timeout", 300);
 pref("apz.drag.enabled", false);
 pref("apz.danger_zone_x", 50);
 pref("apz.danger_zone_y", 100);
+pref("apz.disable_for_scroll_linked_effects", false);
 pref("apz.displayport_expiry_ms", 15000);
 pref("apz.enlarge_displayport_when_clipped", false);
 pref("apz.fling_accel_base_mult", "1.0");
 pref("apz.fling_accel_interval_ms", 500);
 pref("apz.fling_accel_supplemental_mult", "1.0");
 pref("apz.fling_curve_function_x1", "0.0");
 pref("apz.fling_curve_function_y1", "0.0");
 pref("apz.fling_curve_function_x2", "1.0");