/* -*- 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 . * Portions created by the Initial Developer are Copyright (C) 2002 * the Initial Developer. All Rights Reserved. * * Contributor(s): * Boris Zbarsky (original author) * L. David Baron , Mozilla Corporation * Mats Palmgren * * 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 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" #include "nsHTMLReflowState.h" class nsBlockFrame; class gfxDrawable; /** * 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: /** * Use heuristics to figure out the name of the child list that * aChildFrame is currently in. */ static nsIAtom* 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 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); #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 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. * 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 = 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); /** * 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, nsIFrame* aStopAtAncestor); /** * 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(aView->GetClientData()); } /** * GetScrollableFrameFor returns the scrollable frame for a scrolled frame */ static nsIScrollableFrame* GetScrollableFrameFor(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 nsnull 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 nsnull if not found */ static nsIScrollableFrame* GetNearestScrollableFrame(nsIFrame* aFrame); /** * 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); /** * 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 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 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 aFrame, the root frame of a stacking context, find all descendant * frames under the area of a rectangle that receives a mouse event, * or nsnull 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 &aOutFrames, 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); /** * If aIn can be represented exactly using an nsIntRect (i.e. * integer-aligned edges and coordinates in the PRInt32 range) then we * set aOut to that rectangle, otherwise return failure. */ static nsresult GfxRectToIntRect(const gfxRect& aIn, nsIntRect* aOut); 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 }; /** * 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. * * 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(nsIRenderingContext* aRenderingContext, nsIFrame* aFrame, const nsRegion& aDirtyRegion, nscolor aBackstop, PRUint32 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 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(const 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); /** * 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); /* * Likewise, but for 'height', 'min-height', or 'max-height'. */ static nscoord ComputeHeightValue(nscoord aContainingBlockHeight, const nsStyleCoord& aCoord) { nscoord result = ComputeHeightDependentValue(aContainingBlockHeight, aCoord); if (result < 0) result = 0; // clamp calc() return result; } static PRBool 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 PRBool IsPaddingZero(const nsStyleCoord &aCoord) { return (aCoord.GetUnit() == eStyleUnit_Coord && aCoord.GetCoordValue() == 0) || (aCoord.GetUnit() == eStyleUnit_Percent && aCoord.GetPercentValue() == 0.0) || (aCoord.IsCalcUnit() && // clamp negative calc() to 0 nsRuleNode::ComputeCoordPercentCalc(aCoord, nscoord_MAX) <= 0 && nsRuleNode::ComputeCoordPercentCalc(aCoord, 0) <= 0); } static PRBool IsMarginZero(const nsStyleCoord &aCoord) { return (aCoord.GetUnit() == eStyleUnit_Coord && aCoord.GetCoordValue() == 0) || (aCoord.GetUnit() == eStyleUnit_Percent && aCoord.GetPercentValue() == 0.0) || (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( 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). */ 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 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, GraphicsFilter aGraphicsFilter, const nsRect& aDest, const nsRect& aFill, const nsPoint& aAnchor, const nsRect& aDirty, PRUint32 aImageFlags); /** * Convert an nsRect to a gfxRect. */ static gfxRect RectToGfxRect(const nsRect& aRect, PRInt32 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(nsIRenderingContext* 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(nsIRenderingContext* aRenderingContext, imgIContainer* aImage, GraphicsFilter aGraphicsFilter, 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, GraphicsFilter aGraphicsFilter, const nsRect& aDest, const nsRect& aDirty, PRUint32 aImageFlags, const nsRect* aSourceArea = nsnull); /** * 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). * * 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, PRBool& aGotWidth, PRBool& 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); /** * 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, 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 * 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 PRBool 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 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); /** * 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()-> 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 PRBool 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 }; struct SurfaceFromElementResult { SurfaceFromElementResult() : mIsStillLoading(PR_FALSE) {} /* mSurface will contain the resulting surface, or will be NULL on error */ nsRefPtr mSurface; /* The size of the surface */ gfxIntSize mSize; /* The principal associated with the element whose surface was returned */ nsCOMPtr mPrincipal; /* Whether the element was "write only", that is, the bits should not be exposed to content */ PRBool mIsWriteOnly; /* Whether the element was still loading. Some consumers need to handle this case specially. */ PRBool mIsStillLoading; }; static SurfaceFromElementResult SurfaceFromElement(nsIDOMElement *aElement, PRUint32 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: * * * returns the . * * * * With these cases, this returns the . * NOTE: The latter case isn't created normally, however, it can be * created by script with XHTML. * *

* returns NULL because 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 PRBool NeedsPrintPreviewBackground(nsPresContext* aPresContext) { return aPresContext->IsRootPaginatedDocument() && (aPresContext->Type() == nsPresContext::eContext_PrintPreview || aPresContext->Type() == nsPresContext::eContext_PageLayout); } }; class nsSetAttrRunnable : public nsRunnable { public: nsSetAttrRunnable(nsIContent* aContent, nsIAtom* aAttrName, const nsAString& aValue); nsSetAttrRunnable(nsIContent* aContent, nsIAtom* aAttrName, PRInt32 aValue); NS_DECL_NSIRUNNABLE nsCOMPtr mContent; nsCOMPtr mAttrName; nsAutoString mValue; }; class nsUnsetAttrRunnable : public nsRunnable { public: nsUnsetAttrRunnable(nsIContent* aContent, nsIAtom* aAttrName); NS_DECL_NSIRUNNABLE nsCOMPtr mContent; nsCOMPtr 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__