The Tor Browser: gfx/layers/FrameMetrics.h@129ffea94266 (annotated)

gfx/layers/FrameMetrics.h@129ffea94266 (annotated)

gfx/layers/FrameMetrics.h

Sat, 03 Jan 2015 20:18:00 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Sat, 03 Jan 2015 20:18:00 +0100
branch: TOR_BUG_3246
changeset 7: 129ffea94266
permissions: -rw-r--r--

Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #ifndef GFX_FRAMEMETRICS_H
 #define GFX_FRAMEMETRICS_H
 #include <stdint.h>                     // for uint32_t, uint64_t
 #include <string>                       // for std::string
 #include "Units.h"                      // for CSSRect, CSSPixel, etc
 #include "mozilla/gfx/BasePoint.h"      // for BasePoint
 #include "mozilla/gfx/Rect.h"           // for RoundedIn
 #include "mozilla/gfx/ScaleFactor.h"    // for ScaleFactor
 #include "mozilla/gfx/Logging.h"        // for Log
 namespace IPC {
 template <typename T> struct ParamTraits;
 } // namespace IPC
 namespace mozilla {
 // The layer coordinates of the parent layer.
 // This can be arrived at in two ways:
 //   - Start with the CSS coordinates of the parent layer (note: NOT the
 //     CSS coordinates of the current layer, that will give you the wrong
 //     answer), multiply by the device scale and the resolutions of all
 //     layers from the root down to and including the parent.
 //   - Start with global screen coordinates and unapply all CSS and async
 //     transforms from the root down to and including the parent.
 // It's helpful to look at https://wiki.mozilla.org/Platform/GFX/APZ#Coordinate_systems
 // to get a picture of how the various coordinate systems relate to each other.
 struct ParentLayerPixel {};
 typedef gfx::PointTyped<ParentLayerPixel> ParentLayerPoint;
 typedef gfx::RectTyped<ParentLayerPixel> ParentLayerRect;
 typedef gfx::SizeTyped<ParentLayerPixel> ParentLayerSize;
 typedef gfx::IntMarginTyped<ParentLayerPixel> ParentLayerIntMargin;
 typedef gfx::IntPointTyped<ParentLayerPixel> ParentLayerIntPoint;
 typedef gfx::IntRectTyped<ParentLayerPixel> ParentLayerIntRect;
 typedef gfx::IntSizeTyped<ParentLayerPixel> ParentLayerIntSize;
 typedef gfx::ScaleFactor<CSSPixel, ParentLayerPixel> CSSToParentLayerScale;
 typedef gfx::ScaleFactor<LayoutDevicePixel, ParentLayerPixel> LayoutDeviceToParentLayerScale;
 typedef gfx::ScaleFactor<ScreenPixel, ParentLayerPixel> ScreenToParentLayerScale;
 typedef gfx::ScaleFactor<ParentLayerPixel, LayerPixel> ParentLayerToLayerScale;
 typedef gfx::ScaleFactor<ParentLayerPixel, ScreenPixel> ParentLayerToScreenScale;
 namespace layers {
 /**
  * The viewport and displayport metrics for the painted frame at the
  * time of a layer-tree transaction.  These metrics are especially
  * useful for shadow layers, because the metrics values are updated
  * atomically with new pixels.
  */
 struct FrameMetrics {
   friend struct IPC::ParamTraits<mozilla::layers::FrameMetrics>;
 public:
   // We use IDs to identify frames across processes.
   typedef uint64_t ViewID;
   static const ViewID NULL_SCROLL_ID;   // This container layer does not scroll.
   static const ViewID START_SCROLL_ID = 2;  // This is the ID that scrolling subframes
                                         // will begin at.
   FrameMetrics()
     : mCompositionBounds(0, 0, 0, 0)
     , mDisplayPort(0, 0, 0, 0)
     , mCriticalDisplayPort(0, 0, 0, 0)
     , mViewport(0, 0, 0, 0)
     , mScrollableRect(0, 0, 0, 0)
     , mResolution(1)
     , mCumulativeResolution(1)
     , mTransformScale(1)
     , mDevPixelsPerCSSPixel(1)
     , mPresShellId(-1)
     , mMayHaveTouchListeners(false)
     , mIsRoot(false)
     , mHasScrollgrab(false)
     , mScrollId(NULL_SCROLL_ID)
     , mScrollOffset(0, 0)
     , mZoom(1)
     , mUpdateScrollOffset(false)
     , mScrollGeneration(0)
     , mRootCompositionSize(0, 0)
     , mDisplayPortMargins(0, 0, 0, 0)
     , mUseDisplayPortMargins(false)
   {}
   // Default copy ctor and operator= are fine
   bool operator==(const FrameMetrics& aOther) const
   {
     // mContentDescription is not compared on purpose as it's only used
     // for debugging.
     return mCompositionBounds.IsEqualEdges(aOther.mCompositionBounds) &&
            mRootCompositionSize == aOther.mRootCompositionSize &&
            mDisplayPort.IsEqualEdges(aOther.mDisplayPort) &&
            mDisplayPortMargins == aOther.mDisplayPortMargins &&
            mUseDisplayPortMargins == aOther.mUseDisplayPortMargins &&
            mCriticalDisplayPort.IsEqualEdges(aOther.mCriticalDisplayPort) &&
            mViewport.IsEqualEdges(aOther.mViewport) &&
            mScrollableRect.IsEqualEdges(aOther.mScrollableRect) &&
            mResolution == aOther.mResolution &&
            mCumulativeResolution == aOther.mCumulativeResolution &&
            mDevPixelsPerCSSPixel == aOther.mDevPixelsPerCSSPixel &&
            mMayHaveTouchListeners == aOther.mMayHaveTouchListeners &&
            mPresShellId == aOther.mPresShellId &&
            mIsRoot == aOther.mIsRoot &&
            mScrollId == aOther.mScrollId &&
            mScrollOffset == aOther.mScrollOffset &&
            mHasScrollgrab == aOther.mHasScrollgrab &&
            mUpdateScrollOffset == aOther.mUpdateScrollOffset;
   }
   bool operator!=(const FrameMetrics& aOther) const
   {
     return !operator==(aOther);
   }
   bool IsDefault() const
   {
     FrameMetrics def;
     def.mPresShellId = mPresShellId;
     return (def == *this);
   }
   bool IsRootScrollable() const
   {
     return mIsRoot;
   }
   bool IsScrollable() const
   {
     return mScrollId != NULL_SCROLL_ID;
   }
   CSSToLayerScale LayersPixelsPerCSSPixel() const
   {
     return mCumulativeResolution * mDevPixelsPerCSSPixel;
   }
   LayerPoint GetScrollOffsetInLayerPixels() const
   {
     return GetScrollOffset() * LayersPixelsPerCSSPixel();
   }
   LayoutDeviceToParentLayerScale GetParentResolution() const
   {
     return mCumulativeResolution / mResolution;
   }
   // Ensure the scrollableRect is at least as big as the compositionBounds
   // because the scrollableRect can be smaller if the content is not large
   // and the scrollableRect hasn't been updated yet.
   // We move the scrollableRect up because we don't know if we can move it
   // down. i.e. we know that scrollableRect can go back as far as zero.
   // but we don't know how much further ahead it can go.
   CSSRect GetExpandedScrollableRect() const
   {
     CSSRect scrollableRect = mScrollableRect;
     CSSSize compSize = CalculateCompositedSizeInCssPixels();
     if (scrollableRect.width < compSize.width) {
       scrollableRect.x = std::max(0.f,
                                   scrollableRect.x - (compSize.width - scrollableRect.width));
       scrollableRect.width = compSize.width;
     }
     if (scrollableRect.height < compSize.height) {
       scrollableRect.y = std::max(0.f,
                                   scrollableRect.y - (compSize.height - scrollableRect.height));
       scrollableRect.height = compSize.height;
     }
     return scrollableRect;
   }
   // Return the scale factor needed to fit the viewport
   // into its composition bounds.
   CSSToScreenScale CalculateIntrinsicScale() const
   {
     return CSSToScreenScale(float(mCompositionBounds.width) / float(mViewport.width));
   }
   // Return the scale factor for converting from CSS pixels (for this layer)
   // to layer pixels of our parent layer. Much as mZoom is used to interface
   // between inputs we get in screen pixels and quantities in CSS pixels,
   // this is used to interface between mCompositionBounds and quantities
   // in CSS pixels.
   CSSToParentLayerScale GetZoomToParent() const
   {
     return mZoom * mTransformScale;
   }
   CSSSize CalculateCompositedSizeInCssPixels() const
   {
     return mCompositionBounds.Size() / GetZoomToParent();
   }
   CSSRect CalculateCompositedRectInCssPixels() const
   {
     return mCompositionBounds / GetZoomToParent();
   }
   void ScrollBy(const CSSPoint& aPoint)
   {
     mScrollOffset += aPoint;
   }
   void ZoomBy(float aFactor)
   {
     mZoom.scale *= aFactor;
   }
   void CopyScrollInfoFrom(const FrameMetrics& aOther)
   {
     mScrollOffset = aOther.mScrollOffset;
     mScrollGeneration = aOther.mScrollGeneration;
   }
   // ---------------------------------------------------------------------------
   // The following metrics are all in widget space/device pixels.
   //
   // This is the area within the widget that we're compositing to. It is relative
   // to the layer tree origin.
   //
   // This is useful because, on mobile, the viewport and composition dimensions
   // are not always the same. In this case, we calculate the displayport using
   // an area bigger than the region we're compositing to. If we used the
   // viewport dimensions to calculate the displayport, we'd run into situations
   // where we're prerendering the wrong regions and the content may be clipped,
   // or too much of it prerendered. If the composition dimensions are the same as the
   // viewport dimensions, there is no need for this and we can just use the viewport
   // instead.
   //
   // This value is valid for nested scrollable layers as well, and is still
   // relative to the layer tree origin. This value is provided by Gecko at
   // layout/paint time.
   ParentLayerIntRect mCompositionBounds;
   // ---------------------------------------------------------------------------
   // The following metrics are all in CSS pixels. They are not in any uniform
   // space, so each is explained separately.
   //
   // The area of a frame's contents that has been painted, relative to the
   // viewport. It is in the same coordinate space as |mViewport|. For example,
   // if it is at 0,0, then it's at the same place at the viewport, which is at
   // the top-left in the layer, and at the same place as the scroll offset of
   // the document.
   //
   // Note that this is structured in such a way that it doesn't depend on the
   // method layout uses to scroll content.
   //
   // May be larger or smaller than |mScrollableRect|.
   //
   // To pre-render a margin of 100 CSS pixels around the window,
   // { x = -100, y = - 100,
   //   width = window.innerWidth + 200, height = window.innerHeight + 200 }
   CSSRect mDisplayPort;
   // If non-empty, the area of a frame's contents that is considered critical
   // to paint. Area outside of this area (i.e. area inside mDisplayPort, but
   // outside of mCriticalDisplayPort) is considered low-priority, and may be
   // painted with lower precision, or not painted at all.
   //
   // The same restrictions for mDisplayPort apply here.
   CSSRect mCriticalDisplayPort;
   // The CSS viewport, which is the dimensions we're using to constrain the
   // <html> element of this frame, relative to the top-left of the layer. Note
   // that its offset is structured in such a way that it doesn't depend on the
   // method layout uses to scroll content.
   //
   // This is mainly useful on the root layer, however nested iframes can have
   // their own viewport, which will just be the size of the window of the
   // iframe. For layers that don't correspond to a document, this metric is
   // meaningless and invalid.
   CSSRect mViewport;
   // The scrollable bounds of a frame. This is determined by reflow.
   // Ordinarily the x and y will be 0 and the width and height will be the
   // size of the element being scrolled. However for RTL pages or elements
   // the x value may be negative.
   //
   // This is relative to the document. It is in the same coordinate space as
   // |mScrollOffset|, but a different coordinate space than |mViewport| and
   // |mDisplayPort|. Note also that this coordinate system is understood by
   // window.scrollTo().
   //
   // This is valid on any layer unless it has no content.
   CSSRect mScrollableRect;
   // ---------------------------------------------------------------------------
   // The following metrics are dimensionless.
   //
   // The incremental resolution that the current frame has been painted at
   // relative to the parent frame's resolution. This information is provided
   // by Gecko at layout/paint time.
   ParentLayerToLayerScale mResolution;
   // The cumulative resolution that the current frame has been painted at.
   // This is the product of our mResolution and the mResolutions of our parent frames.
   // This information is provided by Gecko at layout/paint time.
   LayoutDeviceToLayerScale mCumulativeResolution;
   // The conversion factor between local screen pixels (the coordinate
   // system in which APZCs receive input events) and our parent layer's
   // layer pixels (the coordinate system of mCompositionBounds).
   // This consists of the scale of the local CSS transform and the
   // nontransient async transform.
   // TODO: APZ does not currently work well if there is a CSS transform
   //       on the layer being scrolled that's not just a scale that's
   //       the same in both directions. When we fix this, mTransformScale
   //       will probably need to turn into a matrix.
   ScreenToParentLayerScale mTransformScale;
   // The conversion factor between CSS pixels and device pixels for this frame.
   // This can vary based on a variety of things, such as reflowing-zoom. The
   // conversion factor for device pixels to layers pixels is just the
   // resolution.
   CSSToLayoutDeviceScale mDevPixelsPerCSSPixel;
   uint32_t mPresShellId;
   // Whether or not this frame may have touch listeners.
   bool mMayHaveTouchListeners;
   // Whether or not this is the root scroll frame for the root content document.
   bool mIsRoot;
   // Whether or not this frame is for an element marked 'scrollgrab'.
   bool mHasScrollgrab;
 public:
   void SetScrollOffset(const CSSPoint& aScrollOffset)
   {
     mScrollOffset = aScrollOffset;
   }
   const CSSPoint& GetScrollOffset() const
   {
     return mScrollOffset;
   }
   void SetZoom(const CSSToScreenScale& aZoom)
   {
     mZoom = aZoom;
   }
   CSSToScreenScale GetZoom() const
   {
     return mZoom;
   }
   void SetScrollOffsetUpdated(uint32_t aScrollGeneration)
   {
     mUpdateScrollOffset = true;
     mScrollGeneration = aScrollGeneration;
   }
   bool GetScrollOffsetUpdated() const
   {
     return mUpdateScrollOffset;
   }
   uint32_t GetScrollGeneration() const
   {
     return mScrollGeneration;
   }
   const std::string& GetContentDescription() const
   {
     return mContentDescription;
   }
   void SetContentDescription(const std::string& aContentDescription)
   {
     mContentDescription = aContentDescription;
   }
   ViewID GetScrollId() const
   {
     return mScrollId;
   }
   void SetScrollId(ViewID scrollId)
   {
     mScrollId = scrollId;
   }
   void SetRootCompositionSize(const CSSSize& aRootCompositionSize)
   {
     mRootCompositionSize = aRootCompositionSize;
   }
   const CSSSize& GetRootCompositionSize() const
   {
     return mRootCompositionSize;
   }
   void SetDisplayPortMargins(const LayerMargin& aDisplayPortMargins)
   {
     mDisplayPortMargins = aDisplayPortMargins;
   }
   const LayerMargin& GetDisplayPortMargins() const
   {
     return mDisplayPortMargins;
   }
   void SetUseDisplayPortMargins()
   {
     mUseDisplayPortMargins = true;
   }
   bool GetUseDisplayPortMargins() const
   {
     return mUseDisplayPortMargins;
   }
 private:
   // New fields from now on should be made private and old fields should
   // be refactored to be private.
   // A unique ID assigned to each scrollable frame.
   ViewID mScrollId;
   // The position of the top-left of the CSS viewport, relative to the document
   // (or the document relative to the viewport, if that helps understand it).
   //
   // Thus it is relative to the document. It is in the same coordinate space as
   // |mScrollableRect|, but a different coordinate space than |mViewport| and
   // |mDisplayPort|.
   //
   // It is required that the rect:
   // { x = mScrollOffset.x, y = mScrollOffset.y,
   //   width = mCompositionBounds.x / mResolution.scale,
   //   height = mCompositionBounds.y / mResolution.scale }
   // Be within |mScrollableRect|.
   //
   // This is valid for any layer, but is always relative to this frame and
   // not any parents, regardless of parent transforms.
   CSSPoint mScrollOffset;
   // The "user zoom". Content is painted by gecko at mResolution * mDevPixelsPerCSSPixel,
   // but will be drawn to the screen at mZoom. In the steady state, the
   // two will be the same, but during an async zoom action the two may
   // diverge. This information is initialized in Gecko but updated in the APZC.
   CSSToScreenScale mZoom;
   // Whether mScrollOffset was updated by something other than the APZ code, and
   // if the APZC receiving this metrics should update its local copy.
   bool mUpdateScrollOffset;
   // The scroll generation counter used to acknowledge the scroll offset update.
   uint32_t mScrollGeneration;
   // A description of the content element corresponding to this frame.
   // This is empty unless the apz.printtree pref is turned on.
   std::string mContentDescription;
   // The size of the root scrollable's composition bounds, but in local CSS pixels.
   CSSSize mRootCompositionSize;
   // A display port expressed as layer margins that apply to the rect of what
   // is drawn of the scrollable element.
   LayerMargin mDisplayPortMargins;
   // If this is true then we use the display port margins on this metrics,
   // otherwise use the display port rect.
   bool mUseDisplayPortMargins;
 };
 /**
  * This class allows us to uniquely identify a scrollable layer. The
  * mLayersId identifies the layer tree (corresponding to a child process
  * and/or tab) that the scrollable layer belongs to. The mPresShellId
  * is a temporal identifier (corresponding to the document loaded that
  * contains the scrollable layer, which may change over time). The
  * mScrollId corresponds to the actual frame that is scrollable.
  */
 struct ScrollableLayerGuid {
   uint64_t mLayersId;
   uint32_t mPresShellId;
   FrameMetrics::ViewID mScrollId;
   ScrollableLayerGuid()
     : mLayersId(0)
     , mPresShellId(0)
     , mScrollId(0)
   {
     MOZ_COUNT_CTOR(ScrollableLayerGuid);
   }
   ScrollableLayerGuid(uint64_t aLayersId, uint32_t aPresShellId,
                       FrameMetrics::ViewID aScrollId)
     : mLayersId(aLayersId)
     , mPresShellId(aPresShellId)
     , mScrollId(aScrollId)
   {
     MOZ_COUNT_CTOR(ScrollableLayerGuid);
   }
   ScrollableLayerGuid(uint64_t aLayersId, const FrameMetrics& aMetrics)
     : mLayersId(aLayersId)
     , mPresShellId(aMetrics.mPresShellId)
     , mScrollId(aMetrics.GetScrollId())
   {
     MOZ_COUNT_CTOR(ScrollableLayerGuid);
   }
   ~ScrollableLayerGuid()
   {
     MOZ_COUNT_DTOR(ScrollableLayerGuid);
   }
   bool operator==(const ScrollableLayerGuid& other) const
   {
     return mLayersId == other.mLayersId
         && mPresShellId == other.mPresShellId
         && mScrollId == other.mScrollId;
   }
   bool operator!=(const ScrollableLayerGuid& other) const
   {
     return !(*this == other);
   }
 };
 template <int LogLevel>
 gfx::Log<LogLevel>& operator<<(gfx::Log<LogLevel>& log, const ScrollableLayerGuid& aGuid) {
   return log << '(' << aGuid.mLayersId << ',' << aGuid.mPresShellId << ',' << aGuid.mScrollId << ')';
 }
 struct ZoomConstraints {
   bool mAllowZoom;
   bool mAllowDoubleTapZoom;
   CSSToScreenScale mMinZoom;
   CSSToScreenScale mMaxZoom;
   ZoomConstraints()
     : mAllowZoom(true)
     , mAllowDoubleTapZoom(true)
   {
     MOZ_COUNT_CTOR(ZoomConstraints);
   }
   ZoomConstraints(bool aAllowZoom,
                   bool aAllowDoubleTapZoom,
                   const CSSToScreenScale& aMinZoom,
                   const CSSToScreenScale& aMaxZoom)
     : mAllowZoom(aAllowZoom)
     , mAllowDoubleTapZoom(aAllowDoubleTapZoom)
     , mMinZoom(aMinZoom)
     , mMaxZoom(aMaxZoom)
   {
     MOZ_COUNT_CTOR(ZoomConstraints);
   }
   ~ZoomConstraints()
   {
     MOZ_COUNT_DTOR(ZoomConstraints);
   }
   bool operator==(const ZoomConstraints& other) const
   {
     return mAllowZoom == other.mAllowZoom
         && mAllowDoubleTapZoom == other.mAllowDoubleTapZoom
         && mMinZoom == other.mMinZoom
         && mMaxZoom == other.mMaxZoom;
   }
   bool operator!=(const ZoomConstraints& other) const
   {
     return !(*this == other);
   }
 };
 }
 }
 #endif /* GFX_FRAMEMETRICS_H */

The Tor Browser / annotate

gfx/layers/FrameMetrics.h@129ffea94266 (annotated)

gfx/layers/FrameMetrics.h