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gecko-dev/layout/base/nsLayoutUtils.h

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/* -*- 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 nsLayoutUtils_h__
#define nsLayoutUtils_h__
class nsIFormControlFrame;
class nsPresContext;
class nsIContent;
class nsIAtom;
class nsIScrollableFrame;
class nsIDOMEvent;
class nsRegion;
class nsDisplayListBuilder;
class nsDisplayItem;
class nsFontMetrics;
class nsClientRectList;
class nsFontFaceList;
class nsHTMLCanvasElement;
class nsHTMLVideoElement;
class nsIImageLoadingContent;
class nsHTMLImageElement;
#include "nsChangeHint.h"
#include "nsStyleContext.h"
#include "nsAutoPtr.h"
#include "nsStyleSet.h"
#include "nsIView.h"
#include "nsIFrame.h"
#include "nsThreadUtils.h"
#include "nsIPresShell.h"
#include "nsIPrincipal.h"
#include "gfxPattern.h"
#include "imgIContainer.h"
#include "nsCSSPseudoElements.h"
#include "nsHTMLReflowState.h"
#include "nsIFrameLoader.h"
#include "FrameMetrics.h"
#include <limits>
class nsBlockFrame;
class gfxDrawable;
namespace mozilla {
namespace dom {
class Element;
} // namespace dom
} // namespace mozilla
/**
* nsLayoutUtils is a namespace class used for various helper
* functions that are useful in multiple places in layout. The goal
* is not to define multiple copies of the same static helper.
*/
class nsLayoutUtils
{
typedef gfxPattern::GraphicsFilter GraphicsFilter;
public:
typedef mozilla::layers::FrameMetrics::ViewID ViewID;
/**
* Finds previously assigned or generates a unique ViewID for the given
* content element.
*/
static ViewID FindIDFor(nsIContent* aContent);
/**
* Find content for given ID.
*/
static nsIContent* FindContentFor(ViewID aId);
/**
* Get display port for the given element.
*/
static bool GetDisplayPort(nsIContent* aContent, nsRect *aResult);
/**
* Use heuristics to figure out the child list that
* aChildFrame is currently in.
*/
static nsIFrame::ChildListID GetChildListNameFor(nsIFrame* aChildFrame);
/**
* GetBeforeFrame returns the outermost :before frame of the given frame, if
* one exists. This is typically O(1). The frame passed in must be
* the first-in-flow.
*
* @param aFrame the frame whose :before is wanted
* @return the :before frame or nullptr if there isn't one
*/
static nsIFrame* GetBeforeFrame(nsIFrame* aFrame);
/**
* GetAfterFrame returns the outermost :after frame of the given frame, if one
* exists. This will walk the in-flow chain to the last-in-flow if
* needed. This function is typically O(N) in the number of child
* frames, following in-flows, etc.
*
* @param aFrame the frame whose :after is wanted
* @return the :after frame or nullptr if there isn't one
*/
static nsIFrame* GetAfterFrame(nsIFrame* aFrame);
/**
* Given a frame, search up the frame tree until we find an
* ancestor that (or the frame itself) is of type aFrameType, if any.
*
* @param aFrame the frame to start at
* @param aFrameType the frame type to look for
* @return a frame of the given type or nullptr if no
* such ancestor exists
*/
static nsIFrame* GetClosestFrameOfType(nsIFrame* aFrame, nsIAtom* aFrameType);
/**
* Given a frame, search up the frame tree until we find an
* ancestor that (or the frame itself) is a "Page" frame, if any.
*
* @param aFrame the frame to start at
* @return a frame of type nsGkAtoms::pageFrame or nullptr if no
* such ancestor exists
*/
static nsIFrame* GetPageFrame(nsIFrame* aFrame)
{
return GetClosestFrameOfType(aFrame, nsGkAtoms::pageFrame);
}
/**
* Given a frame which is the primary frame for an element,
* return the frame that has the non-psuedoelement style context for
* the content.
* This is aPrimaryFrame itself except for tableOuter frames.
*/
static nsIFrame* GetStyleFrame(nsIFrame* aPrimaryFrame);
/**
* IsGeneratedContentFor returns true if aFrame is the outermost
* frame for generated content of type aPseudoElement for aContent.
* aFrame *might not* have the aPseudoElement pseudo-style! For example
* it might be a table outer frame and the inner table frame might
* have the pseudo-style.
*
* @param aContent the content node we're looking at. If this is
* null, then we just assume that aFrame has the right content
* pointer.
* @param aFrame the frame we're looking at
* @param aPseudoElement the pseudo type we're interested in
* @return whether aFrame is the generated aPseudoElement frame for aContent
*/
static bool IsGeneratedContentFor(nsIContent* aContent, nsIFrame* aFrame,
nsIAtom* aPseudoElement);
#ifdef DEBUG
// TODO: remove, see bug 598468.
static bool gPreventAssertInCompareTreePosition;
#endif // DEBUG
/**
* CompareTreePosition determines whether aContent1 comes before or
* after aContent2 in a preorder traversal of the content tree.
*
* @param aCommonAncestor either null, or a common ancestor of
* aContent1 and aContent2. Actually this is
* only a hint; if it's not an ancestor of
* aContent1 or aContent2, this function will
* still work, but it will be slower than
* normal.
* @return < 0 if aContent1 is before aContent2
* > 0 if aContent1 is after aContent2,
* 0 otherwise (meaning they're the same, or they're in
* different documents)
*/
static int32_t CompareTreePosition(nsIContent* aContent1,
nsIContent* aContent2,
const nsIContent* aCommonAncestor = nullptr)
{
return DoCompareTreePosition(aContent1, aContent2, -1, 1, aCommonAncestor);
}
/*
* More generic version of |CompareTreePosition|. |aIf1Ancestor|
* gives the value to return when 1 is an ancestor of 2, and likewise
* for |aIf2Ancestor|. Passing (-1, 1) gives preorder traversal
* order, and (1, -1) gives postorder traversal order.
*/
static int32_t DoCompareTreePosition(nsIContent* aContent1,
nsIContent* aContent2,
int32_t aIf1Ancestor,
int32_t aIf2Ancestor,
const nsIContent* aCommonAncestor = nullptr);
/**
* CompareTreePosition determines whether aFrame1 comes before or
* after aFrame2 in a preorder traversal of the frame tree, where out
* of flow frames are treated as children of their placeholders. This is
* basically the same ordering as DoCompareTreePosition(nsIContent*) except
* that it handles anonymous content properly and there are subtleties with
* continuations.
*
* @param aCommonAncestor either null, or a common ancestor of
* aContent1 and aContent2. Actually this is
* only a hint; if it's not an ancestor of
* aContent1 or aContent2, this function will
* still work, but it will be slower than
* normal.
* @return < 0 if aContent1 is before aContent2
* > 0 if aContent1 is after aContent2,
* 0 otherwise (meaning they're the same, or they're in
* different frame trees)
*/
static int32_t CompareTreePosition(nsIFrame* aFrame1,
nsIFrame* aFrame2,
nsIFrame* aCommonAncestor = nullptr)
{
return DoCompareTreePosition(aFrame1, aFrame2, -1, 1, aCommonAncestor);
}
/*
* More generic version of |CompareTreePosition|. |aIf1Ancestor|
* gives the value to return when 1 is an ancestor of 2, and likewise
* for |aIf2Ancestor|. Passing (-1, 1) gives preorder traversal
* order, and (1, -1) gives postorder traversal order.
*/
static int32_t DoCompareTreePosition(nsIFrame* aFrame1,
nsIFrame* aFrame2,
int32_t aIf1Ancestor,
int32_t aIf2Ancestor,
nsIFrame* aCommonAncestor = nullptr);
/**
* GetLastContinuationWithChild gets the last continuation in aFrame's chain
* that has a child, or the first continuation if the frame has no children.
*/
static nsIFrame* GetLastContinuationWithChild(nsIFrame* aFrame);
/**
* GetLastSibling simply finds the last sibling of aFrame, or returns nullptr if
* aFrame is null.
*/
static nsIFrame* GetLastSibling(nsIFrame* aFrame);
/**
* FindSiblingViewFor locates the child of aParentView that aFrame's
* view should be inserted 'above' (i.e., before in sibling view
* order). This is the first child view of aParentView whose
* corresponding content is before aFrame's content (view siblings
* are in reverse content order).
*/
static nsIView* FindSiblingViewFor(nsIView* aParentView, nsIFrame* aFrame);
/**
* Get the parent of aFrame. If aFrame is the root frame for a document,
* and the document has a parent document in the same view hierarchy, then
* we try to return the subdocumentframe in the parent document.
* @param aExtraOffset [in/out] if non-null, then as we cross documents
* an extra offset may be required and it will be added to aCrossDocOffset.
* Be careful dealing with this extra offset as it is in app units of the
* parent document, which may have a different app units per dev pixel ratio
* than the child document.
*/
static nsIFrame* GetCrossDocParentFrame(const nsIFrame* aFrame,
nsPoint* aCrossDocOffset = nullptr);
/**
* IsProperAncestorFrame checks whether aAncestorFrame is an ancestor
* of aFrame and not equal to aFrame.
* @param aCommonAncestor nullptr, or a common ancestor of aFrame and
* aAncestorFrame. If non-null, this can bound the search and speed up
* the function
*/
static bool IsProperAncestorFrame(nsIFrame* aAncestorFrame, nsIFrame* aFrame,
nsIFrame* aCommonAncestor = nullptr);
/**
* Like IsProperAncestorFrame, but looks across document boundaries.
*
* Just like IsAncestorFrameCrossDoc, except that it returns false when
* aFrame == aAncestorFrame.
*/
static bool IsProperAncestorFrameCrossDoc(nsIFrame* aAncestorFrame, nsIFrame* aFrame,
nsIFrame* aCommonAncestor = nullptr);
/**
* IsAncestorFrameCrossDoc checks whether aAncestorFrame is an ancestor
* of aFrame or equal to aFrame, looking across document boundaries.
* @param aCommonAncestor nullptr, or a common ancestor of aFrame and
* aAncestorFrame. If non-null, this can bound the search and speed up
* the function.
*
* Just like IsProperAncestorFrameCrossDoc, except that it returns true when
* aFrame == aAncestorFrame.
*/
static bool IsAncestorFrameCrossDoc(const nsIFrame* aAncestorFrame, const nsIFrame* aFrame,
const nsIFrame* aCommonAncestor = nullptr);
/**
* Finds the nearest ancestor frame that is the root of an "actively
* scrolled" frame subtree, or aStopAtAncestor if there is no
* such ancestor before we reach aStopAtAncestor in the ancestor chain.
* We expect frames with the same "active scrolled root" to be
* scrolled together, so we'll place them in the same ThebesLayer.
*/
static nsIFrame* GetActiveScrolledRootFor(nsIFrame* aFrame,
const nsIFrame* aStopAtAncestor);
static nsIFrame* GetActiveScrolledRootFor(nsDisplayItem* aItem,
nsDisplayListBuilder* aBuilder,
bool* aShouldFixToViewport = nullptr);
/**
* Returns true if aActiveScrolledRoot is in a content document,
* and its topmost content document ancestor has a root scroll frame with
* a displayport set, and aActiveScrolledRoot is scrolled by that scrollframe.
*/
static bool IsScrolledByRootContentDocumentDisplayportScrolling(const nsIFrame* aActiveScrolledRoot,
nsDisplayListBuilder* aBuilder);
/**
* GetScrollableFrameFor returns the scrollable frame for a scrolled frame
*/
static nsIScrollableFrame* GetScrollableFrameFor(const nsIFrame *aScrolledFrame);
/**
* GetNearestScrollableFrameForDirection locates the first ancestor of
* aFrame (or aFrame itself) that is scrollable with overflow:scroll or
* overflow:auto in the given direction and where either the scrollbar for
* that direction is visible or the frame can be scrolled by some
* positive amount in that direction.
* The search extends across document boundaries.
*
* @param aFrame the frame to start with
* @param aDirection Whether it's for horizontal or vertical scrolling.
* @return the nearest scrollable frame or nullptr if not found
*/
enum Direction { eHorizontal, eVertical };
static nsIScrollableFrame* GetNearestScrollableFrameForDirection(nsIFrame* aFrame,
Direction aDirection);
/**
* GetNearestScrollableFrame locates the first ancestor of aFrame
* (or aFrame itself) that is scrollable with overflow:scroll or
* overflow:auto in some direction.
* The search extends across document boundaries.
*
* @param aFrame the frame to start with
* @return the nearest scrollable frame or nullptr if not found
*/
static nsIScrollableFrame* GetNearestScrollableFrame(nsIFrame* aFrame);
/**
* HasPseudoStyle returns true if aContent (whose primary style
* context is aStyleContext) has the aPseudoElement pseudo-style
* attached to it; returns false otherwise.
*
* @param aContent the content node we're looking at
* @param aStyleContext aContent's style context
* @param aPseudoElement the id of the pseudo style we care about
* @param aPresContext the presentation context
* @return whether aContent has aPseudoElement style attached to it
*/
static bool HasPseudoStyle(nsIContent* aContent,
nsStyleContext* aStyleContext,
nsCSSPseudoElements::Type aPseudoElement,
nsPresContext* aPresContext);
/**
* If this frame is a placeholder for a float, then return the float,
* otherwise return nullptr. aPlaceholder must be a placeholder frame.
*/
static nsIFrame* GetFloatFromPlaceholder(nsIFrame* aPlaceholder);
// Combine aNewBreakType with aOrigBreakType, but limit the break types
// to NS_STYLE_CLEAR_LEFT, RIGHT, LEFT_AND_RIGHT.
static uint8_t CombineBreakType(uint8_t aOrigBreakType, uint8_t aNewBreakType);
/**
* Get the coordinates of a given DOM mouse event, relative to a given
* frame. Works only for DOM events generated by nsGUIEvents.
* @param aDOMEvent the event
* @param aFrame the frame to make coordinates relative to
* @return the point, or (NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE) if
* for some reason the coordinates for the mouse are not known (e.g.,
* the event is not a GUI event).
*/
static nsPoint GetDOMEventCoordinatesRelativeTo(nsIDOMEvent* aDOMEvent,
nsIFrame* aFrame);
/**
* Get the coordinates of a given native mouse event, relative to a given
* frame.
* @param aEvent the event
* @param aFrame the frame to make coordinates relative to
* @return the point, or (NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE) if
* for some reason the coordinates for the mouse are not known (e.g.,
* the event is not a GUI event).
*/
static nsPoint GetEventCoordinatesRelativeTo(const nsEvent* aEvent,
nsIFrame* aFrame);
/**
* Get the coordinates of a given point relative to an event and a
* given frame.
* @param aEvent the event
* @param aPoint the point to get the coordinates relative to
* @param aFrame the frame to make coordinates relative to
* @return the point, or (NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE) if
* for some reason the coordinates for the mouse are not known (e.g.,
* the event is not a GUI event).
*/
static nsPoint GetEventCoordinatesRelativeTo(const nsEvent* aEvent,
const nsIntPoint aPoint,
nsIFrame* aFrame);
/**
* Get the coordinates of a given point relative to a widget and a
* given frame.
* @param aWidget the event src widget
* @param aPoint the point to get the coordinates relative to
* @param aFrame the frame to make coordinates relative to
* @return the point, or (NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE) if
* for some reason the coordinates for the mouse are not known (e.g.,
* the event is not a GUI event).
*/
static nsPoint GetEventCoordinatesRelativeTo(nsIWidget* aWidget,
const nsIntPoint aPoint,
nsIFrame* aFrame);
/**
* Get the popup frame of a given native mouse event.
* @param aPresContext only check popups within aPresContext or a descendant
* @param aEvent the event.
* @return Null, if there is no popup frame at the point, otherwise,
* returns top-most popup frame at the point.
*/
static nsIFrame* GetPopupFrameForEventCoordinates(nsPresContext* aPresContext,
const nsEvent* aEvent);
/**
* Translate from widget coordinates to the view's coordinates
* @param aPresContext the PresContext for the view
* @param aWidget the widget
* @param aPt the point relative to the widget
* @param aView view to which returned coordinates are relative
* @return the point in the view's coordinates
*/
static nsPoint TranslateWidgetToView(nsPresContext* aPresContext,
nsIWidget* aWidget, nsIntPoint aPt,
nsIView* aView);
/**
* Given a matrix and a point, let T be the transformation matrix translating points
* in the coordinate space with origin aOrigin to the coordinate space used by the
* matrix. If M is the stored matrix, this function returns (T-1)MT, the matrix
* that's equivalent to aMatrix but in the coordinate space that treats aOrigin
* as the origin.
*
* @param aOrigin The origin to translate to.
* @param aMatrix The matrix to change the basis of.
* @return A matrix equivalent to aMatrix, but operating in the coordinate system with
* origin aOrigin.
*/
static gfx3DMatrix ChangeMatrixBasis(const gfxPoint3D &aOrigin, const gfx3DMatrix &aMatrix);
/**
* Find IDs corresponding to a scrollable content element in the child process.
* In correspondence with the shadow layer tree, you can use this to perform a
* hit test that corresponds to a specific shadow layer that you can then perform
* transformations on to do parent-side scrolling.
*
* @param aFrame The root frame of a stack context
* @param aTarget The rect to hit test relative to the frame origin
* @param aOutIDs All found IDs are added here
* @param aIgnoreRootScrollFrame a boolean to control if the display list
* builder should ignore the root scroll frame
*/
static nsresult GetRemoteContentIds(nsIFrame* aFrame,
const nsRect& aTarget,
nsTArray<ViewID> &aOutIDs,
bool aIgnoreRootScrollFrame);
/**
* Given aFrame, the root frame of a stacking context, find its descendant
* frame under the point aPt that receives a mouse event at that location,
* or nullptr if there is no such frame.
* @param aPt the point, relative to the frame origin
* @param aShouldIgnoreSuppression a boolean to control if the display
* list builder should ignore paint suppression or not
* @param aIgnoreRootScrollFrame whether or not the display list builder
* should ignore the root scroll frame.
*/
static nsIFrame* GetFrameForPoint(nsIFrame* aFrame, nsPoint aPt,
bool aShouldIgnoreSuppression = false,
bool aIgnoreRootScrollFrame = false);
/**
* Given aFrame, the root frame of a stacking context, find all descendant
* frames under the area of a rectangle that receives a mouse event,
* or nullptr if there is no such frame.
* @param aRect the rect, relative to the frame origin
* @param aOutFrames an array to add all the frames found
* @param aShouldIgnoreSuppression a boolean to control if the display
* list builder should ignore paint suppression or not
* @param aIgnoreRootScrollFrame whether or not the display list builder
* should ignore the root scroll frame.
*/
static nsresult GetFramesForArea(nsIFrame* aFrame, const nsRect& aRect,
nsTArray<nsIFrame*> &aOutFrames,
bool aShouldIgnoreSuppression = false,
bool aIgnoreRootScrollFrame = false);
/**
* Transform aRect relative to aAncestor down to the coordinate system of
* aFrame. Computes the bounding-box of the true quadrilateral.
*/
static nsRect TransformAncestorRectToFrame(nsIFrame* aFrame,
const nsRect& aRect,
const nsIFrame* aAncestor);
/**
* Transform aRect relative to aFrame up to the coordinate system of
* aAncestor. Computes the bounding-box of the true quadrilateral.
*/
static nsRect TransformFrameRectToAncestor(nsIFrame* aFrame,
const nsRect& aRect,
const nsIFrame* aAncestor);
/**
* Gets the transform for aFrame relative to aAncestor. Pass null for aAncestor
* to go up to the root frame.
*/
static gfx3DMatrix GetTransformToAncestor(nsIFrame *aFrame, const nsIFrame *aAncestor);
/**
* Return true if a "layer transform" could be computed for aFrame,
* and optionally return the computed transform. The returned
* transform is what would be set on the layer currently if a layers
* transaction were opened at the time this helper is called.
*/
static bool GetLayerTransformForFrame(nsIFrame* aFrame,
gfx3DMatrix* aTransform);
/**
* Given a point in the global coordinate space, returns that point expressed
* in the coordinate system of aFrame. This effectively inverts all transforms
* between this point and the root frame.
*
* @param aFrame The frame that acts as the coordinate space container.
* @param aPoint The point, in the global space, to get in the frame-local space.
* @return aPoint, expressed in aFrame's canonical coordinate space.
*/
static nsPoint TransformRootPointToFrame(nsIFrame* aFrame,
const nsPoint &aPt);
/**
* Helper function that, given a rectangle and a matrix, returns the smallest
* rectangle containing the image of the source rectangle.
*
* @param aBounds The rectangle to transform.
* @param aMatrix The matrix to transform it with.
* @param aFactor The number of app units per graphics unit.
* @return The smallest rect that contains the image of aBounds.
*/
static nsRect MatrixTransformRect(const nsRect &aBounds,
const gfx3DMatrix &aMatrix, float aFactor);
/**
* Helper function that, given a rectangle and a matrix, returns the smallest
* rectangle containing the image of the source rectangle rounded out to the nearest
* pixel value.
*
* @param aBounds The rectangle to transform.
* @param aMatrix The matrix to transform it with.
* @param aFactor The number of app units per graphics unit.
* @return The smallest rect that contains the image of aBounds.
*/
static nsRect MatrixTransformRectOut(const nsRect &aBounds,
const gfx3DMatrix &aMatrix, float aFactor);
/**
* Helper function that, given a point and a matrix, returns the image
* of that point under the matrix transform.
*
* @param aPoint The point to transform.
* @param aMatrix The matrix to transform it with.
* @param aFactor The number of app units per graphics unit.
* @return The image of the point under the transform.
*/
static nsPoint MatrixTransformPoint(const nsPoint &aPoint,
const gfx3DMatrix &aMatrix, float aFactor);
/**
* Given a graphics rectangle in graphics space, return a rectangle in
* app space that contains the graphics rectangle, rounding out as necessary.
*
* @param aRect The graphics rect to round outward.
* @param aFactor The number of app units per graphics unit.
* @return The smallest rectangle in app space that contains aRect.
*/
static nsRect RoundGfxRectToAppRect(const gfxRect &aRect, float aFactor);
/**
* Returns a subrectangle of aContainedRect that is entirely inside the rounded
* rect. Complex cases are handled conservatively by returning a smaller
* rect than necessary.
*/
static nsRegion RoundedRectIntersectRect(const nsRect& aRoundedRect,
const nscoord aRadii[8],
const nsRect& aContainedRect);
enum {
PAINT_IN_TRANSFORM = 0x01,
PAINT_SYNC_DECODE_IMAGES = 0x02,
PAINT_WIDGET_LAYERS = 0x04,
PAINT_IGNORE_SUPPRESSION = 0x08,
PAINT_DOCUMENT_RELATIVE = 0x10,
PAINT_HIDE_CARET = 0x20,
PAINT_ALL_CONTINUATIONS = 0x40,
PAINT_TO_WINDOW = 0x80,
PAINT_EXISTING_TRANSACTION = 0x100,
PAINT_NO_COMPOSITE = 0x200
};
/**
* Given aFrame, the root frame of a stacking context, paint it and its
* descendants to aRenderingContext.
* @param aRenderingContext a rendering context translated so that (0,0)
* is the origin of aFrame; for best results, (0,0) should transform
* to pixel-aligned coordinates. This can be null, in which case
* aFrame must be a "display root" (root frame for a root document,
* or the root of a popup) with an associated widget and we draw using
* the layer manager for the frame's widget.
* @param aDirtyRegion the region that must be painted, in the coordinates
* of aFrame
* @param aBackstop paint the dirty area with this color before drawing
* the actual content; pass NS_RGBA(0,0,0,0) to draw no background
* @param aFlags if PAINT_IN_TRANSFORM is set, then we assume
* this is inside a transform or SVG foreignObject. If
* PAINT_SYNC_DECODE_IMAGES is set, we force synchronous decode on all
* images. If PAINT_WIDGET_LAYERS is set, aFrame must be a display root,
* and we will use the frame's widget's layer manager to paint
* even if aRenderingContext is non-null. This is useful if you want
* to force rendering to use the widget's layer manager for testing
* or speed. PAINT_WIDGET_LAYERS must be set if aRenderingContext is null.
* If PAINT_DOCUMENT_RELATIVE is used, the visible region is interpreted
* as being relative to the document. (Normally it's relative to the CSS
* viewport.) PAINT_TO_WINDOW sets painting to window to true on the display
* list builder even if we can't tell that we are painting to the window.
* If PAINT_EXISTING_TRANSACTION is set, then BeginTransaction() has already
* been called on aFrame's widget's layer manager and should not be
* called again.
*
* So there are three possible behaviours:
* 1) PAINT_WIDGET_LAYERS is set and aRenderingContext is null; we paint
* by calling BeginTransaction on the widget's layer manager
* 2) PAINT_WIDGET_LAYERS is set and aRenderingContext is non-null; we
* paint by calling BeginTransactionWithTarget on the widget's layer
* maanger
* 3) PAINT_WIDGET_LAYERS is not set and aRenderingContext is non-null;
* we paint by construct a BasicLayerManager and calling
* BeginTransactionWithTarget on it. This is desirable if we're doing
* something like drawWindow in a mode where what gets rendered doesn't
* necessarily correspond to what's visible in the window; we don't
* want to mess up the widget's layer tree.
*/
static nsresult PaintFrame(nsRenderingContext* aRenderingContext, nsIFrame* aFrame,
const nsRegion& aDirtyRegion, nscolor aBackstop,
uint32_t aFlags = 0);
/**
* Compute the used z-index of aFrame; returns zero for elements to which
* z-index does not apply, and for z-index:auto
*/
static int32_t GetZIndex(nsIFrame* aFrame);
/**
* Uses a binary search for find where the cursor falls in the line of text
* It also keeps track of the part of the string that has already been measured
* so it doesn't have to keep measuring the same text over and over
*
* @param "aBaseWidth" contains the width in twips of the portion
* of the text that has already been measured, and aBaseInx contains
* the index of the text that has already been measured.
*
* @param aTextWidth returns the (in twips) the length of the text that falls
* before the cursor aIndex contains the index of the text where the cursor falls
*/
static bool
BinarySearchForPosition(nsRenderingContext* acx,
const PRUnichar* aText,
int32_t aBaseWidth,
int32_t aBaseInx,
int32_t aStartInx,
int32_t aEndInx,
int32_t aCursorPos,
int32_t& aIndex,
int32_t& aTextWidth);
class BoxCallback {
public:
virtual void AddBox(nsIFrame* aFrame) = 0;
};
/**
* Collect all CSS boxes associated with aFrame and its
* continuations, "drilling down" through outer table frames and
* some anonymous blocks since they're not real CSS boxes.
* If aFrame is null, no boxes are returned.
* SVG frames return a single box, themselves.
*/
static void GetAllInFlowBoxes(nsIFrame* aFrame, BoxCallback* aCallback);
class RectCallback {
public:
virtual void AddRect(const nsRect& aRect) = 0;
};
struct RectAccumulator : public RectCallback {
nsRect mResultRect;
nsRect mFirstRect;
bool mSeenFirstRect;
RectAccumulator();
virtual void AddRect(const nsRect& aRect);
};
struct RectListBuilder : public RectCallback {
nsClientRectList* mRectList;
nsresult mRV;
RectListBuilder(nsClientRectList* aList);
virtual void AddRect(const nsRect& aRect);
};
static nsIFrame* GetContainingBlockForClientRect(nsIFrame* aFrame);
enum {
RECTS_ACCOUNT_FOR_TRANSFORMS = 0x01
};
/**
* Collect all CSS border-boxes associated with aFrame and its
* continuations, "drilling down" through outer table frames and
* some anonymous blocks since they're not real CSS boxes.
* The boxes are positioned relative to aRelativeTo (taking scrolling
* into account) and passed to the callback in frame-tree order.
* If aFrame is null, no boxes are returned.
* For SVG frames, returns one rectangle, the bounding box.
* If aFlags includes RECTS_ACCOUNT_FOR_TRANSFORMS, then when converting
* the boxes into aRelativeTo coordinates, transforms (including CSS
* and SVG transforms) are taken into account.
*/
static void GetAllInFlowRects(nsIFrame* aFrame, nsIFrame* aRelativeTo,
RectCallback* aCallback, uint32_t aFlags = 0);
/**
* The same as GetAllInFlowRects, but it collects the CSS padding-boxes
* rather than the CSS border-boxes. SVG frames are handled the same way
* as in GetAllInFlowRects.
*/
static void GetAllInFlowPaddingRects(nsIFrame* aFrame, nsIFrame* aRelativeTo,
RectCallback* aCallback, uint32_t aFlags = 0);
/**
* Computes the union of all rects returned by GetAllInFlowRects. If
* the union is empty, returns the first rect.
* If aFlags includes RECTS_ACCOUNT_FOR_TRANSFORMS, then when converting
* the boxes into aRelativeTo coordinates, transforms (including CSS
* and SVG transforms) are taken into account.
*/
static nsRect GetAllInFlowRectsUnion(nsIFrame* aFrame, nsIFrame* aRelativeTo,
uint32_t aFlags = 0);
/**
* The same as GetAllInFlowRectsUnion, but it computes the union of the
* rects returned by GetAllInFlowPaddingRects.
*/
static nsRect GetAllInFlowPaddingRectsUnion(nsIFrame* aFrame,
nsIFrame* aRelativeTo,
uint32_t aFlags = 0);
enum {
EXCLUDE_BLUR_SHADOWS = 0x01
};
/**
* Takes a text-shadow array from the style properties of a given nsIFrame and
* computes the union of those shadows along with the given initial rect.
* If there are no shadows, the initial rect is returned.
*/
static nsRect GetTextShadowRectsUnion(const nsRect& aTextAndDecorationsRect,
nsIFrame* aFrame,
uint32_t aFlags = 0);
/**
* Get the font metrics corresponding to the frame's style data.
* @param aFrame the frame
* @param aFontMetrics the font metrics result
* @param aSizeInflation number to multiply font size by
* @return success or failure code
*/
static nsresult GetFontMetricsForFrame(const nsIFrame* aFrame,
nsFontMetrics** aFontMetrics,
float aSizeInflation = 1.0f);
/**
* Get the font metrics corresponding to the given style data.
* @param aStyleContext the style data
* @param aFontMetrics the font metrics result
* @param aSizeInflation number to multiply font size by
* @return success or failure code
*/
static nsresult GetFontMetricsForStyleContext(nsStyleContext* aStyleContext,
nsFontMetrics** aFontMetrics,
float aSizeInflation = 1.0f);
/**
* Find the immediate child of aParent whose frame subtree contains
* aDescendantFrame. Returns null if aDescendantFrame is not a descendant
* of aParent.
*/
static nsIFrame* FindChildContainingDescendant(nsIFrame* aParent, nsIFrame* aDescendantFrame);
/**
* Find the nearest ancestor that's a block
*/
static nsBlockFrame* FindNearestBlockAncestor(nsIFrame* aFrame);
/**
* Find the nearest ancestor that's not for generated content. Will return
* aFrame if aFrame is not for generated content.
*/
static nsIFrame* GetNonGeneratedAncestor(nsIFrame* aFrame);
/**
* Cast aFrame to an nsBlockFrame* or return null if it's not
* an nsBlockFrame.
*/
static nsBlockFrame* GetAsBlock(nsIFrame* aFrame);
/*
* Whether the frame is an nsBlockFrame which is not a wrapper block.
*/
static bool IsNonWrapperBlock(nsIFrame* aFrame) {
return GetAsBlock(aFrame) && !aFrame->IsBlockWrapper();
}
/**
* If aFrame is an out of flow frame, return its placeholder, otherwise
* return its parent.
*/
static nsIFrame* GetParentOrPlaceholderFor(nsIFrame* aFrame);
/**
* If aFrame is an out of flow frame, return its placeholder, otherwise
* return its (possibly cross-doc) parent.
*/
static nsIFrame* GetParentOrPlaceholderForCrossDoc(nsIFrame* aFrame);
/**
* Get a frame's next-in-flow, or, if it doesn't have one, its special sibling.
*/
static nsIFrame*
GetNextContinuationOrSpecialSibling(nsIFrame *aFrame);
/**
* Get the first frame in the continuation-plus-special-sibling chain
* containing aFrame.
*/
static nsIFrame*
GetFirstContinuationOrSpecialSibling(nsIFrame *aFrame);
/**
* Check whether aFrame is a part of the scrollbar or scrollcorner of
* the root content.
* @param aFrame the checking frame
* @return if TRUE, the frame is a part of the scrollbar or scrollcorner of
* the root content.
*/
static bool IsViewportScrollbarFrame(nsIFrame* aFrame);
/**
* Get the contribution of aFrame to its containing block's intrinsic
* width. This considers the child's intrinsic width, its 'width',
* 'min-width', and 'max-width' properties, and its padding, border,
* and margin.
*/
enum IntrinsicWidthType { MIN_WIDTH, PREF_WIDTH };
static nscoord IntrinsicForContainer(nsRenderingContext* aRenderingContext,
nsIFrame* aFrame,
IntrinsicWidthType aType);
/*
* Convert nsStyleCoord to nscoord when percentages depend on the
* containing block width.
*/
static nscoord ComputeWidthDependentValue(
nscoord aContainingBlockWidth,
const nsStyleCoord& aCoord);
/*
* Convert nsStyleCoord to nscoord when percentages depend on the
* containing block width, and enumerated values are for width,
* min-width, or max-width. Returns the content-box width value based
* on aContentEdgeToBoxSizing and aBoxSizingToMarginEdge (which are
* also used for the enumerated values for width. This function does
* not handle 'auto'. It ensures that the result is nonnegative.
*
* @param aRenderingContext Rendering context for font measurement/metrics.
* @param aFrame Frame whose (min-/max-/)width is being computed
* @param aContainingBlockWidth Width of aFrame's containing block.
* @param aContentEdgeToBoxSizing The sum of any left/right padding and
* border that goes inside the rect chosen by -moz-box-sizing.
* @param aBoxSizingToMarginEdge The sum of any left/right padding, border,
* and margin that goes outside the rect chosen by -moz-box-sizing.
* @param aCoord The width value to compute.
*/
static nscoord ComputeWidthValue(
nsRenderingContext* aRenderingContext,
nsIFrame* aFrame,
nscoord aContainingBlockWidth,
nscoord aContentEdgeToBoxSizing,
nscoord aBoxSizingToMarginEdge,
const nsStyleCoord& aCoord);
/*
* Convert nsStyleCoord to nscoord when percentages depend on the
* containing block height.
*/
static nscoord ComputeHeightDependentValue(
nscoord aContainingBlockHeight,
const nsStyleCoord& aCoord);
/*
* Likewise, but for 'height', 'min-height', or 'max-height'.
*/
static nscoord ComputeHeightValue(nscoord aContainingBlockHeight,
nscoord aContentEdgeToBoxSizingBoxEdge,
const nsStyleCoord& aCoord)
{
MOZ_ASSERT(aContainingBlockHeight != NS_AUTOHEIGHT || !aCoord.HasPercent(),
"caller must deal with %% of unconstrained height");
MOZ_ASSERT(aCoord.IsCoordPercentCalcUnit());
nscoord result =
nsRuleNode::ComputeCoordPercentCalc(aCoord, aContainingBlockHeight);
// Clamp calc(), and the subtraction for box-sizing.
return NS_MAX(0, result - aContentEdgeToBoxSizingBoxEdge);
}
static bool IsAutoHeight(const nsStyleCoord &aCoord, nscoord aCBHeight)
{
nsStyleUnit unit = aCoord.GetUnit();
return unit == eStyleUnit_Auto || // only for 'height'
unit == eStyleUnit_None || // only for 'max-height'
(aCBHeight == NS_AUTOHEIGHT && aCoord.HasPercent());
}
static bool IsPaddingZero(const nsStyleCoord &aCoord)
{
return (aCoord.GetUnit() == eStyleUnit_Coord &&
aCoord.GetCoordValue() == 0) ||
(aCoord.GetUnit() == eStyleUnit_Percent &&
aCoord.GetPercentValue() == 0.0f) ||
(aCoord.IsCalcUnit() &&
// clamp negative calc() to 0
nsRuleNode::ComputeCoordPercentCalc(aCoord, nscoord_MAX) <= 0 &&
nsRuleNode::ComputeCoordPercentCalc(aCoord, 0) <= 0);
}
static bool IsMarginZero(const nsStyleCoord &aCoord)
{
return (aCoord.GetUnit() == eStyleUnit_Coord &&
aCoord.GetCoordValue() == 0) ||
(aCoord.GetUnit() == eStyleUnit_Percent &&
aCoord.GetPercentValue() == 0.0f) ||
(aCoord.IsCalcUnit() &&
nsRuleNode::ComputeCoordPercentCalc(aCoord, nscoord_MAX) == 0 &&
nsRuleNode::ComputeCoordPercentCalc(aCoord, 0) == 0);
}
/*
* Calculate the used values for 'width' and 'height' for a replaced element.
*
* http://www.w3.org/TR/CSS21/visudet.html#min-max-widths
*/
static nsSize ComputeSizeWithIntrinsicDimensions(
nsRenderingContext* aRenderingContext, nsIFrame* aFrame,
const nsIFrame::IntrinsicSize& aIntrinsicSize,
nsSize aIntrinsicRatio, nsSize aCBSize,
nsSize aMargin, nsSize aBorder, nsSize aPadding);
/*
* Calculate the used values for 'width' and 'height' when width
* and height are 'auto'. The tentWidth and tentHeight arguments should be
* the result of applying the rules for computing intrinsic sizes and ratios.
* as specified by CSS 2.1 sections 10.3.2 and 10.6.2
*/
static nsSize ComputeAutoSizeWithIntrinsicDimensions(nscoord minWidth, nscoord minHeight,
nscoord maxWidth, nscoord maxHeight,
nscoord tentWidth, nscoord tentHeight);
// Implement nsIFrame::GetPrefWidth in terms of nsIFrame::AddInlinePrefWidth
static nscoord PrefWidthFromInline(nsIFrame* aFrame,
nsRenderingContext* aRenderingContext);
// Implement nsIFrame::GetMinWidth in terms of nsIFrame::AddInlineMinWidth
static nscoord MinWidthFromInline(nsIFrame* aFrame,
nsRenderingContext* aRenderingContext);
// Get a suitable foreground color for painting aProperty for aFrame.
static nscolor GetColor(nsIFrame* aFrame, nsCSSProperty aProperty);
// Get a baseline y position in app units that is snapped to device pixels.
static gfxFloat GetSnappedBaselineY(nsIFrame* aFrame, gfxContext* aContext,
nscoord aY, nscoord aAscent);
static void DrawString(const nsIFrame* aFrame,
nsRenderingContext* aContext,
const PRUnichar* aString,
int32_t aLength,
nsPoint aPoint,
uint8_t aDirection = NS_STYLE_DIRECTION_INHERIT);
static nscoord GetStringWidth(const nsIFrame* aFrame,
nsRenderingContext* aContext,
const PRUnichar* aString,
int32_t aLength);
/**
* Helper function for drawing text-shadow. The callback's job
* is to draw whatever needs to be blurred onto the given context.
*/
typedef void (* TextShadowCallback)(nsRenderingContext* aCtx,
nsPoint aShadowOffset,
const nscolor& aShadowColor,
void* aData);
static void PaintTextShadow(const nsIFrame* aFrame,
nsRenderingContext* aContext,
const nsRect& aTextRect,
const nsRect& aDirtyRect,
const nscolor& aForegroundColor,
TextShadowCallback aCallback,
void* aCallbackData);
/**
* Gets the baseline to vertically center text from a font within a
* line of specified height.
*
* Returns the baseline position relative to the top of the line.
*/
static nscoord GetCenteredFontBaseline(nsFontMetrics* aFontMetrics,
nscoord aLineHeight);
/**
* Derive a baseline of |aFrame| (measured from its top border edge)
* from its first in-flow line box (not descending into anything with
* 'overflow' not 'visible', potentially including aFrame itself).
*
* Returns true if a baseline was found (and fills in aResult).
* Otherwise returns false.
*/
static bool GetFirstLineBaseline(const nsIFrame* aFrame, nscoord* aResult);
/**
* Just like GetFirstLineBaseline, except also returns the top and
* bottom of the line with the baseline.
*
* Returns true if a line was found (and fills in aResult).
* Otherwise returns false.
*/
struct LinePosition {
nscoord mTop, mBaseline, mBottom;
LinePosition operator+(nscoord aOffset) const {
LinePosition result;
result.mTop = mTop + aOffset;
result.mBaseline = mBaseline + aOffset;
result.mBottom = mBottom + aOffset;
return result;
}
};
static bool GetFirstLinePosition(const nsIFrame* aFrame,
LinePosition* aResult);
/**
* Derive a baseline of |aFrame| (measured from its top border edge)
* from its last in-flow line box (not descending into anything with
* 'overflow' not 'visible', potentially including aFrame itself).
*
* Returns true if a baseline was found (and fills in aResult).
* Otherwise returns false.
*/
static bool GetLastLineBaseline(const nsIFrame* aFrame, nscoord* aResult);
/**
* Returns a y coordinate relative to this frame's origin that represents
* the logical bottom of the frame or its visible content, whichever is lower.
* Relative positioning is ignored and margins and glyph bounds are not
* considered.
* This value will be >= mRect.height() and <= overflowRect.YMost() unless
* relative positioning is applied.
*/
static nscoord CalculateContentBottom(nsIFrame* aFrame);
/**
* Gets the closest frame (the frame passed in or one of its parents) that
* qualifies as a "layer"; used in DOM0 methods that depends upon that
* definition. This is the nearest frame that is either positioned or scrolled
* (the child of a scroll frame).
*/
static nsIFrame* GetClosestLayer(nsIFrame* aFrame);
/**
* Gets the graphics filter for the frame
*/
static GraphicsFilter GetGraphicsFilterForFrame(nsIFrame* aFrame);
/* N.B. The only difference between variants of the Draw*Image
* functions below is the type of the aImage argument.
*/
/**
* Draw a background image. The image's dimensions are as specified in aDest;
* the image itself is not consulted to determine a size.
* See https://wiki.mozilla.org/Gecko:Image_Snapping_and_Rendering
* @param aRenderingContext Where to draw the image, set up with an
* appropriate scale and transform for drawing in
* app units.
* @param aImage The image.
* @param aImageSize The unscaled size of the image being drawn.
* (This might be the image's size if no scaling
* occurs, or it might be the image's size if
* the image is a vector image being rendered at
* that size.)
* @param aDest The position and scaled area where one copy of
* the image should be drawn.
* @param aFill The area to be filled with copies of the
* image.
* @param aAnchor A point in aFill which we will ensure is
* pixel-aligned in the output.
* @param aDirty Pixels outside this area may be skipped.
* @param aImageFlags Image flags of the imgIContainer::FLAG_* variety
*/
static nsresult DrawBackgroundImage(nsRenderingContext* aRenderingContext,
imgIContainer* aImage,
const nsIntSize& aImageSize,
GraphicsFilter aGraphicsFilter,
const nsRect& aDest,
const nsRect& aFill,
const nsPoint& aAnchor,
const nsRect& aDirty,
uint32_t aImageFlags);
/**
* Draw an image.
* See https://wiki.mozilla.org/Gecko:Image_Snapping_and_Rendering
* @param aRenderingContext Where to draw the image, set up with an
* appropriate scale and transform for drawing in
* app units.
* @param aImage The image.
* @param aDest Where one copy of the image should mapped to.
* @param aFill The area to be filled with copies of the
* image.
* @param aAnchor A point in aFill which we will ensure is
* pixel-aligned in the output.
* @param aDirty Pixels outside this area may be skipped.
* @param aImageFlags Image flags of the imgIContainer::FLAG_* variety
*/
static nsresult DrawImage(nsRenderingContext* aRenderingContext,
imgIContainer* aImage,
GraphicsFilter aGraphicsFilter,
const nsRect& aDest,
const nsRect& aFill,
const nsPoint& aAnchor,
const nsRect& aDirty,
uint32_t aImageFlags);
/**
* Convert an nsRect to a gfxRect.
*/
static gfxRect RectToGfxRect(const nsRect& aRect,
int32_t aAppUnitsPerDevPixel);
/**
* Draw a drawable using the pixel snapping algorithm.
* See https://wiki.mozilla.org/Gecko:Image_Snapping_and_Rendering
* @param aRenderingContext Where to draw the image, set up with an
* appropriate scale and transform for drawing in
* app units.
* @param aDrawable The drawable we want to draw.
* @param aFilter The graphics filter we should draw with.
* @param aDest Where one copy of the image should mapped to.
* @param aFill The area to be filled with copies of the
* image.
* @param aAnchor A point in aFill which we will ensure is
* pixel-aligned in the output.
* @param aDirty Pixels outside this area may be skipped.
*/
static void DrawPixelSnapped(nsRenderingContext* aRenderingContext,
gfxDrawable* aDrawable,
GraphicsFilter aFilter,
const nsRect& aDest,
const nsRect& aFill,
const nsPoint& aAnchor,
const nsRect& aDirty);
/**
* Draw a whole image without scaling or tiling.
*
* @param aRenderingContext Where to draw the image, set up with an
* appropriate scale and transform for drawing in
* app units.
* @param aImage The image.
* @param aDest The top-left where the image should be drawn
* @param aDirty If non-null, then pixels outside this area may
* be skipped.
* @param aImageFlags Image flags of the imgIContainer::FLAG_* variety
* @param aSourceArea If non-null, this area is extracted from
* the image and drawn at aDest. It's
* in appunits. For best results it should
* be aligned with image pixels.
*/
static nsresult DrawSingleUnscaledImage(nsRenderingContext* aRenderingContext,
imgIContainer* aImage,
GraphicsFilter aGraphicsFilter,
const nsPoint& aDest,
const nsRect* aDirty,
uint32_t aImageFlags,
const nsRect* aSourceArea = nullptr);
/**
* Draw a whole image without tiling.
*
* @param aRenderingContext Where to draw the image, set up with an
* appropriate scale and transform for drawing in
* app units.
* @param aImage The image.
* @param aDest The area that the image should fill
* @param aDirty Pixels outside this area may be skipped.
* @param aSourceArea If non-null, this area is extracted from
* the image and drawn in aDest. It's
* in appunits. For best results it should
* be aligned with image pixels.
* @param aImageFlags Image flags of the imgIContainer::FLAG_* variety
*/
static nsresult DrawSingleImage(nsRenderingContext* aRenderingContext,
imgIContainer* aImage,
GraphicsFilter aGraphicsFilter,
const nsRect& aDest,
const nsRect& aDirty,
uint32_t aImageFlags,
const nsRect* aSourceArea = nullptr);
/**
* Given an imgIContainer, this method attempts to obtain an intrinsic
* px-valued height & width for it. If the imgIContainer has a non-pixel
* value for either height or width, this method tries to generate a pixel
* value for that dimension using the intrinsic ratio (if available). The
* intrinsic ratio will be assigned to aIntrinsicRatio; if there's no
* intrinsic ratio then (0, 0) will be assigned.
*
* This method will always set aGotWidth and aGotHeight to indicate whether
* we were able to successfully obtain (or compute) a value for each
* dimension.
*
* NOTE: This method is similar to ComputeSizeWithIntrinsicDimensions. The
* difference is that this one is simpler and is suited to places where we
* have less information about the frame tree.
*/
static void ComputeSizeForDrawing(imgIContainer* aImage,
nsIntSize& aImageSize,
nsSize& aIntrinsicRatio,
bool& aGotWidth,
bool& aGotHeight);
/**
* Given a source area of an image (in appunits) and a destination area
* that we want to map that source area too, computes the area that
* would be covered by the whole image. This is useful for passing to
* the aDest parameter of DrawImage, when we want to draw a subimage
* of an overall image.
*/
static nsRect GetWholeImageDestination(const nsIntSize& aWholeImageSize,
const nsRect& aImageSourceArea,
const nsRect& aDestArea);
/**
* Determine if any corner radius is of nonzero size
* @param aCorners the |nsStyleCorners| object to check
* @return true unless all the coordinates are 0%, 0 or null.
*
* A corner radius with one dimension zero and one nonzero is
* treated as a nonzero-radius corner, even though it will end up
* being rendered like a zero-radius corner. This is because such
* corners are not expected to appear outside of test cases, and it's
* simpler to implement the test this way.
*/
static bool HasNonZeroCorner(const nsStyleCorners& aCorners);
/**
* Determine if there is any corner radius on corners adjacent to the
* given side.
*/
static bool HasNonZeroCornerOnSide(const nsStyleCorners& aCorners,
mozilla::css::Side aSide);
/**
* Determine if a widget is likely to require transparency or translucency.
* @param aBackgroundFrame The frame that the background is set on. For
* <window>s, this will be the canvas frame.
* @param aCSSRootFrame The frame that holds CSS properties affecting
* the widget's transparency. For menupopups,
* aBackgroundFrame and aCSSRootFrame will be the
* same.
* @return a value suitable for passing to SetWindowTranslucency
*/
static nsTransparencyMode GetFrameTransparency(nsIFrame* aBackgroundFrame,
nsIFrame* aCSSRootFrame);
/**
* A frame is a popup if it has its own floating window. Menus, panels
* and combobox dropdowns are popups.
*/
static bool IsPopup(nsIFrame* aFrame);
/**
* Find the nearest "display root". This is the nearest enclosing
* popup frame or the root prescontext's root frame.
*/
static nsIFrame* GetDisplayRootFrame(nsIFrame* aFrame);
/**
* Get textrun construction flags determined by a given style; in particular
* some combination of:
* -- TEXT_DISABLE_OPTIONAL_LIGATURES if letter-spacing is in use
* -- TEXT_OPTIMIZE_SPEED if the text-rendering CSS property and font size
* and prefs indicate we should be optimizing for speed over quality
*/
static uint32_t GetTextRunFlagsForStyle(nsStyleContext* aStyleContext,
const nsStyleFont* aStyleFont,
nscoord aLetterSpacing);
/**
* Takes two rectangles whose origins must be the same, and computes
* the difference between their union and their intersection as two
* rectangles. (This difference is a superset of the difference
* between the two rectangles.)
*/
static void GetRectDifferenceStrips(const nsRect& aR1, const nsRect& aR2,
nsRect* aHStrip, nsRect* aVStrip);
/**
* Get a device context that can be used to get up-to-date device
* dimensions for the given window. For some reason, this is more
* complicated than it ought to be in multi-monitor situations.
*/
static nsDeviceContext*
GetDeviceContextForScreenInfo(nsPIDOMWindow* aWindow);
/**
* Some frames with 'position: fixed' (nsStylePosition::mDisplay ==
* NS_STYLE_POSITION_FIXED) are not really fixed positioned, since
* they're inside an element with -moz-transform. This function says
* whether such an element is a real fixed-pos element.
*/
static bool IsReallyFixedPos(nsIFrame* aFrame);
/**
* Return true if aFrame is in an {ib} split and is NOT one of the
* continuations of the first inline in it.
*/
static bool FrameIsNonFirstInIBSplit(const nsIFrame* aFrame) {
return (aFrame->GetStateBits() & NS_FRAME_IS_SPECIAL) &&
aFrame->GetFirstContinuation()->
Properties().Get(nsIFrame::IBSplitSpecialPrevSibling());
}
/**
* Return true if aFrame is in an {ib} split and is NOT one of the
* continuations of the last inline in it.
*/
static bool FrameIsNonLastInIBSplit(const nsIFrame* aFrame) {
return (aFrame->GetStateBits() & NS_FRAME_IS_SPECIAL) &&
aFrame->GetFirstContinuation()->
Properties().Get(nsIFrame::IBSplitSpecialSibling());
}
/**
* Obtain a gfxASurface from the given DOM element, if possible.
* This obtains the most natural surface from the element; that
* is, the one that can be obtained with the fewest conversions.
*
* The flags below can modify the behaviour of this function. The
* result is returned as a SurfaceFromElementResult struct, also
* defined below.
*
* Currently, this will do:
* - HTML Canvas elements: will return the underlying canvas surface
* - HTML Video elements: will return the current video frame
* - Image elements: will return the image
*
* The above results are modified by the below flags (copying,
* forcing image surface, etc.).
*/
enum {
/* Always create a new surface for the result */
SFE_WANT_NEW_SURFACE = 1 << 0,
/* When creating a new surface, create an image surface */
SFE_WANT_IMAGE_SURFACE = 1 << 1,
/* Whether to extract the first frame (as opposed to the
current frame) in the case that the element is an image. */
SFE_WANT_FIRST_FRAME = 1 << 2,
/* Whether we should skip colorspace/gamma conversion */
SFE_NO_COLORSPACE_CONVERSION = 1 << 3,
/* Whether we should skip premultiplication -- the resulting
image will always be an image surface, and must not be given to
Thebes for compositing! */
SFE_NO_PREMULTIPLY_ALPHA = 1 << 4
};
struct SurfaceFromElementResult {
SurfaceFromElementResult() :
// Use safe default values here
mIsWriteOnly(true), mIsStillLoading(false), mCORSUsed(false) {}
/* mSurface will contain the resulting surface, or will be NULL on error */
nsRefPtr<gfxASurface> mSurface;
/* The size of the surface */
gfxIntSize mSize;
/* The principal associated with the element whose surface was returned.
If there is a surface, this will never be null. */
nsCOMPtr<nsIPrincipal> mPrincipal;
/* The image request, if the element is an nsIImageLoadingContent */
nsCOMPtr<imgIRequest> mImageRequest;
/* Whether the element was "write only", that is, the bits should not be exposed to content */
bool mIsWriteOnly;
/* Whether the element was still loading. Some consumers need to handle
this case specially. */
bool mIsStillLoading;
/* Whether the element used CORS when loading. */
bool mCORSUsed;
};
static SurfaceFromElementResult SurfaceFromElement(mozilla::dom::Element *aElement,
uint32_t aSurfaceFlags = 0);
static SurfaceFromElementResult SurfaceFromElement(nsIImageLoadingContent *aElement,
uint32_t aSurfaceFlags = 0);
// Need an nsHTMLImageElement overload, because otherwise the
// nsIImageLoadingContent and mozilla::dom::Element overloads are ambiguous
// for nsHTMLImageElement.
static SurfaceFromElementResult SurfaceFromElement(nsHTMLImageElement *aElement,
uint32_t aSurfaceFlags = 0);
static SurfaceFromElementResult SurfaceFromElement(nsHTMLCanvasElement *aElement,
uint32_t aSurfaceFlags = 0);
static SurfaceFromElementResult SurfaceFromElement(nsHTMLVideoElement *aElement,
uint32_t aSurfaceFlags = 0);
/**
* When the document is editable by contenteditable attribute of its root
* content or body content.
*
* Be aware, this returns NULL if it's in designMode.
*
* For example:
*
* <html contenteditable="true"><body></body></html>
* returns the <html>.
*
* <html><body contenteditable="true"></body></html>
* <body contenteditable="true"></body>
* With these cases, this returns the <body>.
* NOTE: The latter case isn't created normally, however, it can be
* created by script with XHTML.
*
* <body><p contenteditable="true"></p></body>
* returns NULL because <body> isn't editable.
*/
static nsIContent*
GetEditableRootContentByContentEditable(nsIDocument* aDocument);
/**
* Returns true if the passed in prescontext needs the dark grey background
* that goes behind the page of a print preview presentation.
*/
static bool NeedsPrintPreviewBackground(nsPresContext* aPresContext) {
return aPresContext->IsRootPaginatedDocument() &&
(aPresContext->Type() == nsPresContext::eContext_PrintPreview ||
aPresContext->Type() == nsPresContext::eContext_PageLayout);
}
/**
* Adds all font faces used in the frame tree starting from aFrame
* to the list aFontFaceList.
*/
static nsresult GetFontFacesForFrames(nsIFrame* aFrame,
nsFontFaceList* aFontFaceList);
/**
* Adds all font faces used within the specified range of text in aFrame,
* and optionally its continuations, to the list in aFontFaceList.
* Pass 0 and INT32_MAX for aStartOffset and aEndOffset to specify the
* entire text is to be considered.
*/
static nsresult GetFontFacesForText(nsIFrame* aFrame,
int32_t aStartOffset,
int32_t aEndOffset,
bool aFollowContinuations,
nsFontFaceList* aFontFaceList);
/**
* Walks the frame tree starting at aFrame looking for textRuns.
* If |clear| is true, just clears the TEXT_RUN_MEMORY_ACCOUNTED flag
* on each textRun found (and |aMallocSizeOf| is not used).
* If |clear| is false, adds the storage used for each textRun to the
* total, and sets the TEXT_RUN_MEMORY_ACCOUNTED flag to avoid double-
* accounting. (Runs with this flag already set will be skipped.)
* Expected usage pattern is therefore to call twice:
* (void)SizeOfTextRunsForFrames(rootFrame, nullptr, true);
* total = SizeOfTextRunsForFrames(rootFrame, mallocSizeOf, false);
*/
static size_t SizeOfTextRunsForFrames(nsIFrame* aFrame,
nsMallocSizeOfFun aMallocSizeOf,
bool clear);
/**
* Returns true if the content node has animations or transitions that can be
* performed on the compositor.
*/
static bool HasAnimationsForCompositor(nsIContent* aContent,
nsCSSProperty aProperty);
/**
* Checks if CSS 3D transforms are currently enabled.
*/
static bool Are3DTransformsEnabled();
/**
* Checks if off-main-thread transform and opacity animations are enabled.
*/
static bool AreOpacityAnimationsEnabled();
static bool AreTransformAnimationsEnabled();
/**
* Checks if we should warn about animations that can't be async
*/
static bool IsAnimationLoggingEnabled();
/**
* Checks if we should forcibly use nearest pixel filtering for the
* background.
*/
static bool UseBackgroundNearestFiltering();
/**
* Checks whether we want to use the GPU to scale images when
* possible.
*/
static bool GPUImageScalingEnabled();
/**
* Unions the overflow areas of all non-popup children of aFrame with
* aOverflowAreas.
*/
static void UnionChildOverflow(nsIFrame* aFrame,
nsOverflowAreas& aOverflowAreas);
/**
* Return whether this is a frame whose width is used when computing
* the font size inflation of its descendants.
*/
static bool IsContainerForFontSizeInflation(const nsIFrame *aFrame)
{
return aFrame->GetStateBits() & NS_FRAME_FONT_INFLATION_CONTAINER;
}
/**
* Return the font size inflation *ratio* for a given frame. This is
* the factor by which font sizes should be inflated; it is never
* smaller than 1.
*/
static float FontSizeInflationFor(const nsIFrame *aFrame);
/**
* Perform the first half of the computation of FontSizeInflationFor
* (see above).
* This includes determining whether inflation should be performed
* within this container and returning 0 if it should not be.
*
* The result is guaranteed not to vary between line participants
* (inlines, text frames) within a line.
*
* The result should not be used directly since font sizes slightly
* above the minimum should always be adjusted as done by
* FontSizeInflationInner.
*/
static nscoord InflationMinFontSizeFor(const nsIFrame *aFrame);
/**
* Perform the second half of the computation done by
* FontSizeInflationFor (see above).
*
* aMinFontSize must be the result of one of the
* InflationMinFontSizeFor methods above.
*/
static float FontSizeInflationInner(const nsIFrame *aFrame,
nscoord aMinFontSize);
static bool FontSizeInflationEnabled(nsPresContext *aPresContext);
/**
* See comment above "font.size.inflation.maxRatio" in
* modules/libpref/src/init/all.js .
*/
static uint32_t FontSizeInflationMaxRatio() {
return sFontSizeInflationMaxRatio;
}
/**
* See comment above "font.size.inflation.emPerLine" in
* modules/libpref/src/init/all.js .
*/
static uint32_t FontSizeInflationEmPerLine() {
return sFontSizeInflationEmPerLine;
}
/**
* See comment above "font.size.inflation.minTwips" in
* modules/libpref/src/init/all.js .
*/
static uint32_t FontSizeInflationMinTwips() {
return sFontSizeInflationMinTwips;
}
/**
* See comment above "font.size.inflation.lineThreshold" in
* modules/libpref/src/init/all.js .
*/
static uint32_t FontSizeInflationLineThreshold() {
return sFontSizeInflationLineThreshold;
}
/**
* See comment above "font.size.inflation.mappingIntercept" in
* modules/libpref/src/init/all.js .
*/
static int32_t FontSizeInflationMappingIntercept() {
return sFontSizeInflationMappingIntercept;
}
static void Initialize();
static void Shutdown();
/**
* Register an imgIRequest object with a refresh driver.
*
* @param aPresContext The nsPresContext whose refresh driver we want to
* register with.
* @param aRequest A pointer to the imgIRequest object which the client wants
* to register with the refresh driver.
* @param aRequestRegistered A pointer to a boolean value which indicates
* whether the given image request is registered. If
* *aRequestRegistered is true, then this request will not be
* registered again. If the request is registered by this function,
* then *aRequestRegistered will be set to true upon the completion of
* this function.
*
*/
static void RegisterImageRequest(nsPresContext* aPresContext,
imgIRequest* aRequest,
bool* aRequestRegistered);
/**
* Register an imgIRequest object with a refresh driver, but only if the
* request is for an image that is animated.
*
* @param aPresContext The nsPresContext whose refresh driver we want to
* register with.
* @param aRequest A pointer to the imgIRequest object which the client wants
* to register with the refresh driver.
* @param aRequestRegistered A pointer to a boolean value which indicates
* whether the given image request is registered. If
* *aRequestRegistered is true, then this request will not be
* registered again. If the request is registered by this function,
* then *aRequestRegistered will be set to true upon the completion of
* this function.
*
*/
static void RegisterImageRequestIfAnimated(nsPresContext* aPresContext,
imgIRequest* aRequest,
bool* aRequestRegistered);
/**
* Deregister an imgIRequest object from a refresh driver.
*
* @param aPresContext The nsPresContext whose refresh driver we want to
* deregister from.
* @param aRequest A pointer to the imgIRequest object with which the client
* previously registered and now wants to deregister from the refresh
* driver.
* @param aRequestRegistered A pointer to a boolean value which indicates
* whether the given image request is registered. If
* *aRequestRegistered is false, then this request will not be
* deregistered. If the request is deregistered by this function,
* then *aRequestRegistered will be set to false upon the completion of
* this function.
*/
static void DeregisterImageRequest(nsPresContext* aPresContext,
imgIRequest* aRequest,
bool* aRequestRegistered);
/**
* Shim to nsCSSFrameConstructor::PostRestyleEvent. Exists so that we
* can avoid including nsCSSFrameConstructor.h and all its dependencies
* in content files.
*/
static void PostRestyleEvent(mozilla::dom::Element* aElement,
nsRestyleHint aRestyleHint,
nsChangeHint aMinChangeHint);
/**
* Updates a pair of x and y distances if a given point is closer to a given
* rectangle than the original distance values. If aPoint is closer to
* aRect than aClosestXDistance and aClosestYDistance indicate, then those
* two variables are updated with the distance between aPoint and aRect,
* and true is returned. If aPoint is not closer, then aClosestXDistance
* and aClosestYDistance are left unchanged, and false is returned.
*
* Distances are measured in the two dimensions separately; a closer x
* distance beats a closer y distance.
*/
template<typename PointType, typename RectType, typename CoordType>
static bool PointIsCloserToRect(PointType aPoint, const RectType& aRect,
CoordType& aClosestXDistance,
CoordType& aClosestYDistance);
#ifdef DEBUG
/**
* Assert that there are no duplicate continuations of the same frame
* within aFrameList. Optimize the tests by assuming that all frames
* in aFrameList have parent aContainer.
*/
static void
AssertNoDuplicateContinuations(nsIFrame* aContainer,
const nsFrameList& aFrameList);
/**
* Assert that the frame tree rooted at |aSubtreeRoot| is empty, i.e.,
* that it contains no first-in-flows.
*/
static void
AssertTreeOnlyEmptyNextInFlows(nsIFrame *aSubtreeRoot);
#endif
private:
static uint32_t sFontSizeInflationEmPerLine;
static uint32_t sFontSizeInflationMinTwips;
static uint32_t sFontSizeInflationLineThreshold;
static int32_t sFontSizeInflationMappingIntercept;
static uint32_t sFontSizeInflationMaxRatio;
};
template<typename PointType, typename RectType, typename CoordType>
/* static */ bool
nsLayoutUtils::PointIsCloserToRect(PointType aPoint, const RectType& aRect,
CoordType& aClosestXDistance,
CoordType& aClosestYDistance)
{
CoordType fromLeft = aPoint.x - aRect.x;
CoordType fromRight = aPoint.x - aRect.XMost();
CoordType xDistance;
if (fromLeft >= 0 && fromRight <= 0) {
xDistance = 0;
} else {
xDistance = NS_MIN(abs(fromLeft), abs(fromRight));
}
if (xDistance <= aClosestXDistance) {
if (xDistance < aClosestXDistance) {
aClosestYDistance = std::numeric_limits<CoordType>::max();
}
CoordType fromTop = aPoint.y - aRect.y;
CoordType fromBottom = aPoint.y - aRect.YMost();
CoordType yDistance;
if (fromTop >= 0 && fromBottom <= 0) {
yDistance = 0;
} else {
yDistance = NS_MIN(abs(fromTop), abs(fromBottom));
}
if (yDistance < aClosestYDistance) {
aClosestXDistance = xDistance;
aClosestYDistance = yDistance;
return true;
}
}
return false;
}
namespace mozilla {
namespace layout {
/**
* An RAII class which will, for the duration of its lifetime,
* **if** the frame given is a container for font size inflation,
* set the current inflation container on the pres context to null
* (and then, in its destructor, restore the old value).
*/
class AutoMaybeDisableFontInflation {
public:
AutoMaybeDisableFontInflation(nsIFrame *aFrame)
{
// FIXME: Now that inflation calculations are based on the flow
// root's NCA's (nearest common ancestor of its inflatable
// descendants) width, we could probably disable inflation in
// fewer cases than we currently do.
if (nsLayoutUtils::IsContainerForFontSizeInflation(aFrame)) {
mPresContext = aFrame->PresContext();
mOldValue = mPresContext->mInflationDisabledForShrinkWrap;
mPresContext->mInflationDisabledForShrinkWrap = true;
} else {
// indicate we have nothing to restore
mPresContext = nullptr;
}
}
~AutoMaybeDisableFontInflation()
{
if (mPresContext) {
mPresContext->mInflationDisabledForShrinkWrap = mOldValue;
}
}
private:
nsPresContext *mPresContext;
bool mOldValue;
};
}
}
class nsSetAttrRunnable : public nsRunnable
{
public:
nsSetAttrRunnable(nsIContent* aContent, nsIAtom* aAttrName,
const nsAString& aValue);
nsSetAttrRunnable(nsIContent* aContent, nsIAtom* aAttrName,
int32_t aValue);
NS_DECL_NSIRUNNABLE
nsCOMPtr<nsIContent> mContent;
nsCOMPtr<nsIAtom> mAttrName;
nsAutoString mValue;
};
class nsUnsetAttrRunnable : public nsRunnable
{
public:
nsUnsetAttrRunnable(nsIContent* aContent, nsIAtom* aAttrName);
NS_DECL_NSIRUNNABLE
nsCOMPtr<nsIContent> mContent;
nsCOMPtr<nsIAtom> mAttrName;
};
class nsReflowFrameRunnable : public nsRunnable
{
public:
nsReflowFrameRunnable(nsIFrame* aFrame,
nsIPresShell::IntrinsicDirty aIntrinsicDirty,
nsFrameState aBitToAdd);
NS_DECL_NSIRUNNABLE
nsWeakFrame mWeakFrame;
nsIPresShell::IntrinsicDirty mIntrinsicDirty;
nsFrameState mBitToAdd;
};
#endif // nsLayoutUtils_h__
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