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pjs/layout/base/nsLayoutUtils.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla.org code.
*
* The Initial Developer of the Original Code is
* Boris Zbarsky <bzbarsky@mit.edu>.
* Portions created by the Initial Developer are Copyright (C) 2002
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Boris Zbarsky <bzbarsky@mit.edu> (original author)
* L. David Baron <dbaron@dbaron.org>, Mozilla Corporation
* Mats Palmgren <mats.palmgren@bredband.net>
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef nsLayoutUtils_h__
#define nsLayoutUtils_h__
class nsIFormControlFrame;
class nsPresContext;
class nsIContent;
class nsIAtom;
class nsIScrollableView;
class nsIScrollableFrame;
class nsIDOMEvent;
class nsRegion;
class nsDisplayListBuilder;
class nsIFontMetrics;
class nsClientRectList;
#include "prtypes.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"
class nsBlockFrame;
class nsTextFragment;
/**
* 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
{
public:
/**
* 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 nsnull 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 nsnull 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 nsnull 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 nsnull 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 PR_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 PRBool IsGeneratedContentFor(nsIContent* aContent, nsIFrame* aFrame,
nsIAtom* aPseudoElement);
/**
* 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 PRInt32 CompareTreePosition(nsIContent* aContent1,
nsIContent* aContent2,
const nsIContent* aCommonAncestor = nsnull)
{
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 PRInt32 DoCompareTreePosition(nsIContent* aContent1,
nsIContent* aContent2,
PRInt32 aIf1Ancestor,
PRInt32 aIf2Ancestor,
const nsIContent* aCommonAncestor = nsnull);
/**
* 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 PRInt32 CompareTreePosition(nsIFrame* aFrame1,
nsIFrame* aFrame2,
nsIFrame* aCommonAncestor = nsnull)
{
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 PRInt32 DoCompareTreePosition(nsIFrame* aFrame1,
nsIFrame* aFrame2,
PRInt32 aIf1Ancestor,
PRInt32 aIf2Ancestor,
nsIFrame* aCommonAncestor = nsnull);
/**
* 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 nsnull 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
*/
static nsIFrame* GetCrossDocParentFrame(const nsIFrame* aFrame,
nsPoint* aCrossDocOffset = nsnull);
/**
* IsProperAncestorFrame checks whether aAncestorFrame is an ancestor
* of aFrame and not equal to aFrame.
* @param aCommonAncestor nsnull, or a common ancestor of aFrame and
* aAncestorFrame. If non-null, this can bound the search and speed up
* the function
*/
static PRBool IsProperAncestorFrame(nsIFrame* aAncestorFrame, nsIFrame* aFrame,
nsIFrame* aCommonAncestor = nsnull);
/**
* Like IsProperAncestorFrame, but looks across document boundaries.
*
* Just like IsAncestorFrameCrossDoc, except that it returns false when
* aFrame == aAncestorFrame.
*/
static PRBool IsProperAncestorFrameCrossDoc(nsIFrame* aAncestorFrame, nsIFrame* aFrame,
nsIFrame* aCommonAncestor = nsnull);
/**
* IsAncestorFrameCrossDoc checks whether aAncestorFrame is an ancestor
* of aFrame or equal to aFrame, looking across document boundaries.
* @param aCommonAncestor nsnull, 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 PRBool IsAncestorFrameCrossDoc(nsIFrame* aAncestorFrame, nsIFrame* aFrame,
nsIFrame* aCommonAncestor = nsnull);
/**
* GetFrameFor returns the root frame for a view
* @param aView is the view to return the root frame for
* @return the root frame for the view
*/
static nsIFrame* GetFrameFor(nsIView *aView)
{ return static_cast<nsIFrame*>(aView->GetClientData()); }
/**
* GetScrollableFrameFor returns the scrollable frame for a scrollable view
* @param aScrollableView is the scrollable view to return the
* scrollable frame for.
* @return the scrollable frame for the scrollable view
*/
static nsIScrollableFrame* GetScrollableFrameFor(nsIScrollableView *aScrollableView);
/**
* GetScrollableFrameFor returns the scrollable frame for a scrolled frame
*/
static nsIScrollableFrame* GetScrollableFrameFor(nsIFrame *aScrolledFrame);
static nsPresContext::ScrollbarStyles
ScrollbarStylesOfView(nsIScrollableView *aScrollableView);
/**
* GetNearestScrollingView locates the first ancestor of aView (or
* aView itself) that is scrollable. It does *not* count an
* 'overflow' style of 'hidden' as scrollable, even though a scrolling
* view is present. Thus, the direction of the scroll is needed as
* an argument.
*
* @param aView the view we're looking at
* @param aDirection Whether it's for horizontal or vertical scrolling.
* @return the nearest scrollable view or nsnull if not found
*/
enum Direction { eHorizontal, eVertical, eEither };
static nsIScrollableView* GetNearestScrollingView(nsIView* aView,
Direction aDirection);
/**
* HasPseudoStyle returns PR_TRUE if aContent (whose primary style
* context is aStyleContext) has the aPseudoElement pseudo-style
* attached to it; returns PR_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 PRBool HasPseudoStyle(nsIContent* aContent,
nsStyleContext* aStyleContext,
nsCSSPseudoElements::Type aPseudoElement,
nsPresContext* aPresContext)
{
NS_PRECONDITION(aPresContext, "Must have a prescontext");
nsRefPtr<nsStyleContext> pseudoContext;
if (aContent) {
pseudoContext = aPresContext->StyleSet()->
ProbePseudoElementStyle(aContent, aPseudoElement, aStyleContext);
}
return pseudoContext != nsnull;
}
/**
* If this frame is a placeholder for a float, then return the float,
* otherwise return nsnull. 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 PRUint8 CombineBreakType(PRUint8 aOrigBreakType, PRUint8 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 native mouse event, relative to the nearest
* view for a given frame.
* The "nearest view" is the view returned by nsFrame::GetOffsetFromView.
* XXX this is extremely BOGUS because "nearest view" is a mess; every
* use of this method is really a bug!
* @param aEvent the event
* @param aFrame the frame to make coordinates relative to
* @param aView view to which returned coordinates are relative
* @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 GetEventCoordinatesForNearestView(nsEvent* aEvent,
nsIFrame* aFrame,
nsIView** aView = nsnull);
/**
* 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 gfxMatrix ChangeMatrixBasis(const gfxPoint &aOrigin, const gfxMatrix &aMatrix);
/**
* 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 nsnull 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,
PRBool aShouldIgnoreSuppression = PR_FALSE,
PRBool aIgnoreRootScrollFrame = PR_FALSE);
/**
* 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 InvertTransformsToRoot(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 gfxMatrix &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 gfxMatrix &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);
enum {
PAINT_IN_TRANSFORM = 0x01,
PAINT_SYNC_DECODE_IMAGES = 0x02
};
/**
* 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
* @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.
*/
static nsresult PaintFrame(nsIRenderingContext* aRenderingContext, nsIFrame* aFrame,
const nsRegion& aDirtyRegion, nscolor aBackstop,
PRUint32 aFlags = 0);
/**
* @param aRootFrame the root frame of the tree to be displayed
* @param aMovingFrame a frame that has moved
* @param aPt the amount by which aMovingFrame has moved
* @param aUpdateRect a rectangle that bounds the area to be updated,
* relative to aRootFrame
* @param aRepaintRegion output: a subregion of aUpdateRect that must be
* repainted after doing the blit
* @param aBlitRegion output: a subregion of aUpdateRect that should
* be repainted by blitting
*
* If the caller does a bitblt copy of aBlitRegion-aPt to aBlitRegion,
* and then repaints aRepaintRegion, then the area aUpdateRect will be
* correctly up to date. aBlitRegion and aRepaintRegion do not intersect
* and are both contained within aUpdateRect.
*
* Frame geometry must have already been adjusted for the scroll/copy
* operation before this function is called.
*
* Conceptually it works by computing a display list in the before-state
* and a display list in the after-state and analyzing them to find the
* differences. In practice it is only feasible to build a display list
* in the after-state (plus building two display lists would be less
* efficient), so we use some unfortunately tricky techniques to get by
* with just the after-list.
*
* We compute the "visible moving area", a region that contains all
* moving content that is visible, either before or after scrolling,
* intersected with aUpdateRect.
*
* The aRepaintRegion region consists of the visible moving area
* intersected with the union of the following areas:
* a) any visible background-attachment:fixed areas in the after-move display
* list
* b) any visible areas of the before-move display list corresponding to
* frames that will not move (translated by aDelta)
* c) any visible areas of the after-move display list corresponding to
* frames that did not move
*
* aBlitRegion is the visible moving area minus aRepaintRegion.
*
* We may return a larger region for aRepaintRegion and/or aBlitRegion
* if computing the above regions precisely is too expensive. (However,
* they will never intersect, since the regions that may be computed
* imprecisely are really the "visible moving area" and aRepaintRegion.)
*/
static nsresult ComputeRepaintRegionForCopy(nsIFrame* aRootFrame,
nsIFrame* aMovingFrame,
nsPoint aDelta,
const nsRect& aUpdateRect,
nsRegion* aBlitRegion,
nsRegion* aRepaintRegion);
/**
* Compute the used z-index of aFrame; returns zero for elements to which
* z-index does not apply, and for z-index:auto
*/
static PRInt32 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 PRBool
BinarySearchForPosition(nsIRenderingContext* acx,
const PRUnichar* aText,
PRInt32 aBaseWidth,
PRInt32 aBaseInx,
PRInt32 aStartInx,
PRInt32 aEndInx,
PRInt32 aCursorPos,
PRInt32& aIndex,
PRInt32& 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;
PRPackedBool 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);
/**
* 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.
*/
static void GetAllInFlowRects(nsIFrame* aFrame, nsIFrame* aRelativeTo,
RectCallback* aCallback);
/**
* Computes the union of all rects returned by GetAllInFlowRects. If
* the union is empty, returns the first rect.
*/
static nsRect GetAllInFlowRectsUnion(nsIFrame* aFrame, nsIFrame* aRelativeTo);
/**
* 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);
/**
* Get the font metrics corresponding to the frame's style data.
* @param aFrame the frame
* @param aFontMetrics the font metrics result
* @return success or failure code
*/
static nsresult GetFontMetricsForFrame(nsIFrame* aFrame,
nsIFontMetrics** aFontMetrics);
/**
* Get the font metrics corresponding to the given style data.
* @param aStyleContext the style data
* @param aFontMetrics the font metrics result
* @return success or failure code
*/
static nsresult GetFontMetricsForStyleContext(nsStyleContext* aStyleContext,
nsIFontMetrics** aFontMetrics);
/**
* 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);
/**
* If aFrame is an out of flow frame, return its placeholder, otherwise
* return its parent.
*/
static nsIFrame* GetParentOrPlaceholderFor(nsFrameManager* aFrameManager,
nsIFrame* aFrame);
/**
* Find the closest common ancestor of aFrame1 and aFrame2, following
* out of flow frames to their placeholders instead of their parents. Returns
* nsnull if the frames are in different frame trees.
*
* @param aKnownCommonAncestorHint a frame that is believed to be on the
* ancestor chain of both aFrame1 and aFrame2. If null, or a frame that is
* not in fact on both ancestor chains, then this function will still return
* the correct result, but it will be slower.
*/
static nsIFrame*
GetClosestCommonAncestorViaPlaceholders(nsIFrame* aFrame1, nsIFrame* aFrame2,
nsIFrame* aKnownCommonAncestorHint);
/**
* 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 PRBool 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(nsIRenderingContext* 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(
nsIRenderingContext* 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);
/*
* 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(
nsIRenderingContext* aRenderingContext, nsIFrame* aFrame,
const nsIFrame::IntrinsicSize& aIntrinsicSize,
nsSize aIntrinsicRatio, nsSize aCBSize,
nsSize aMargin, nsSize aBorder, nsSize aPadding);
// Implement nsIFrame::GetPrefWidth in terms of nsIFrame::AddInlinePrefWidth
static nscoord PrefWidthFromInline(nsIFrame* aFrame,
nsIRenderingContext* aRenderingContext);
// Implement nsIFrame::GetMinWidth in terms of nsIFrame::AddInlineMinWidth
static nscoord MinWidthFromInline(nsIFrame* aFrame,
nsIRenderingContext* aRenderingContext);
static void DrawString(const nsIFrame* aFrame,
nsIRenderingContext* aContext,
const PRUnichar* aString,
PRInt32 aLength,
nsPoint aPoint,
PRUint8 aDirection = NS_STYLE_DIRECTION_INHERIT);
static nscoord GetStringWidth(const nsIFrame* aFrame,
nsIRenderingContext* aContext,
const PRUnichar* aString,
PRInt32 aLength);
/**
* 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(nsIFontMetrics* 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 PRBool 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 PRBool 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 PRBool 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). In Gecko terms, it's approximately
* equivalent to having a view, at least for simple HTML. However, views are
* going away, so this is a cleaner definition.
*/
static nsIFrame* GetClosestLayer(nsIFrame* aFrame);
/**
* Gets the graphics filter for the frame
*/
static gfxPattern::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 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(nsIRenderingContext* aRenderingContext,
imgIContainer* aImage,
gfxPattern::GraphicsFilter aGraphicsFilter,
const nsRect& aDest,
const nsRect& aFill,
const nsPoint& aAnchor,
const nsRect& aDirty,
PRUint32 aImageFlags);
/**
* 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 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(nsIRenderingContext* aRenderingContext,
imgIContainer* aImage,
const nsPoint& aDest,
const nsRect& aDirty,
PRUint32 aImageFlags,
const nsRect* aSourceArea = nsnull);
/**
* 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(nsIRenderingContext* aRenderingContext,
imgIContainer* aImage,
gfxPattern::GraphicsFilter aGraphicsFilter,
const nsRect& aDest,
const nsRect& aDirty,
PRUint32 aImageFlags,
const nsRect* aSourceArea = nsnull);
/**
* 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);
/**
* Set the font on aRC based on the style in aSC
*/
static void SetFontFromStyle(nsIRenderingContext* aRC, nsStyleContext* aSC);
/**
* Determine if any corner radius is of nonzero size
* @param aCorners the |nsStyleCorners| object to check
* @return PR_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 PRBool HasNonZeroCorner(const nsStyleCorners& aCorners);
/**
* Determine if there is any corner radius on corners adjacent to the
* given side.
*/
static PRBool HasNonZeroCornerOnSide(const nsStyleCorners& aCorners,
PRUint8 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);
/**
* 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 PRUint32 GetTextRunFlagsForStyle(nsStyleContext* aStyleContext,
const nsStyleText* aStyleText,
const nsStyleFont* aStyleFont);
/**
* 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 docshell. For some reason, this is more
* complicated than it ought to be in multi-monitor situations.
*/
static nsIDeviceContext*
GetDeviceContextForScreenInfo(nsIDocShell* aDocShell);
/**
* 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 PRBool IsReallyFixedPos(nsIFrame* aFrame);
/**
* Indicates if the nsIFrame::GetUsedXXX assertions in nsFrame.cpp should
* disabled.
*/
static PRBool sDisableGetUsedXAssertions;
/**
* Returns the text fragment, which aFrame should use for printing.
* @param aFrame The nsIFrame object, which uses text fragment data.
*/
static nsTextFragment* GetTextFragmentForPrinting(const 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 PRBool FrameIsNonFirstInIBSplit(const nsIFrame* aFrame) {
return (aFrame->GetStateBits() & NS_FRAME_IS_SPECIAL) &&
aFrame->GetFirstContinuation()->
GetProperty(nsGkAtoms::IBSplitSpecialPrevSibling);
}
/**
* Return true if aFrame is in an {ib} split and is NOT one of the
* continuations of the last inline in it.
*/
static PRBool FrameIsNonLastInIBSplit(const nsIFrame* aFrame) {
return (aFrame->GetStateBits() & NS_FRAME_IS_SPECIAL) &&
aFrame->GetFirstContinuation()->
GetProperty(nsGkAtoms::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
};
struct SurfaceFromElementResult {
/* 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 */
nsCOMPtr<nsIPrincipal> mPrincipal;
/* Whether the element was "write only", that is, the bits should not be exposed to content */
PRBool mIsWriteOnly;
};
static SurfaceFromElementResult SurfaceFromElement(nsIDOMElement *aElement,
PRUint32 aSurfaceFlags = 0);
};
class nsAutoDisableGetUsedXAssertions
{
public:
nsAutoDisableGetUsedXAssertions()
: mOldValue(nsLayoutUtils::sDisableGetUsedXAssertions)
{
nsLayoutUtils::sDisableGetUsedXAssertions = PR_TRUE;
}
~nsAutoDisableGetUsedXAssertions()
{
nsLayoutUtils::sDisableGetUsedXAssertions = mOldValue;
}
private:
PRBool mOldValue;
};
class nsSetAttrRunnable : public nsRunnable
{
public:
nsSetAttrRunnable(nsIContent* aContent, nsIAtom* aAttrName,
const nsAString& 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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