/* * 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 MathML Project. * * The Initial Developer of the Original Code is The University Of * Queensland. Portions created by The University Of Queensland are * Copyright (C) 1999 The University Of Queensland. All Rights Reserved. * * Contributor(s): * Roger B. Sidje * David J. Fiddes * Shyjan Mahamud (added TeX rendering rules) */ #ifndef nsMathMLContainerFrame_h___ #define nsMathMLContainerFrame_h___ #include "nsCOMPtr.h" #include "nsIViewManager.h" #include "nsHTMLContainerFrame.h" #include "nsBlockFrame.h" #include "nsInlineFrame.h" #include "nsMathMLAtoms.h" #include "nsMathMLOperators.h" #include "nsMathMLChar.h" #include "nsIMathMLFrame.h" #include "nsMathMLParts.h" /* * Base class for MathML container frames. It acts like an inferred * mrow. By default, this frame uses its Reflow() method to lay its * children horizontally and ensure that their baselines are aligned. * The Reflow() method relies upon Place() to position children. * By overloading Place() in derived classes, it is therefore possible * to position children in various customized ways. * * This frame is a *math-aware frame* in the sense that given the markup * base arguments, the method InsertScriptLevelStyleContext() * can be used to render the 'base' in normal-font, and the 'arguments' * in small-font. This is a common functionality to tags like msub, msup, * msubsup, mover, munder, munderover, mmultiscripts. All are derived * from this base class. They use SetInitialChildList() to trigger * InsertScriptLevelStyleContext() for the very first time as soon as all * their children are known. However, each of these tags has its own * Reflow() and/or Place() methods to lay its children as appropriate, * thus overriding the default behavior in this base class. * * Other tags like mi that do not have 'arguments' can be derived from * this base class as well. The class caters for empty arguments. * Notice that mi implements its own SetInitialChildList() method * to switch to a normal-font (rather than italics) if its text content * is not a single character (as per the MathML REC). * */ class nsMathMLContainerFrame : public nsHTMLContainerFrame, public nsIMathMLFrame { public: // nsIMathMLFrame methods -- see documentation in nsIMathMLFrame.h NS_IMETHOD QueryInterface(REFNSIID aIID, void** aInstancePtr); NS_IMETHOD_(nsrefcnt) AddRef(void); NS_IMETHOD_(nsrefcnt) Release(void); NS_IMETHOD GetBoundingMetrics(nsBoundingMetrics& aBoundingMetrics); NS_IMETHOD SetBoundingMetrics(const nsBoundingMetrics& aBoundingMetrics); NS_IMETHOD GetReference(nsPoint& aReference); NS_IMETHOD SetReference(const nsPoint& aReference); NS_IMETHOD Stretch(nsIPresContext* aPresContext, nsIRenderingContext& aRenderingContext, nsStretchDirection aStretchDirection, nsStretchMetrics& aContainerSize, nsStretchMetrics& aDesiredStretchSize); #if 0 NS_IMETHOD GetDesiredStretchSize(nsIPresContext* aPresContext, nsIRenderingContext& aRenderingContext, nsStretchMetrics& aDesiredStretchSize); #endif NS_IMETHOD Place(nsIPresContext* aPresContext, nsIRenderingContext& aRenderingContext, PRBool aPlaceOrigin, nsHTMLReflowMetrics& aDesiredSize); NS_IMETHOD EmbellishOperator(); NS_IMETHOD GetEmbellishData(nsEmbellishData& aEmbellishData); NS_IMETHOD SetEmbellishData(const nsEmbellishData& aEmbellishData); NS_IMETHOD GetPresentationData(PRInt32* aScriptLevel, PRBool* aDisplayStyle); NS_IMETHOD UpdatePresentationData(PRInt32 aScriptLevelIncrement, PRBool aDisplayStyle); NS_IMETHOD UpdatePresentationDataFromChildAt(PRInt32 aIndex, PRInt32 aScriptLevelIncrement, PRBool aDisplayStyle); // nsHTMLContainerFrame methods NS_IMETHOD Init(nsIPresContext* aPresContext, nsIContent* aContent, nsIFrame* aParent, nsIStyleContext* aContext, nsIFrame* aPrevInFlow); NS_IMETHOD SetInitialChildList(nsIPresContext* aPresContext, nsIAtom* aListName, nsIFrame* aChildList); NS_IMETHOD Reflow(nsIPresContext* aPresContext, nsHTMLReflowMetrics& aDesiredSize, const nsHTMLReflowState& aReflowState, nsReflowStatus& aStatus); NS_IMETHOD DidReflow(nsIPresContext* aPresContext, nsDidReflowStatus aStatus) { mEmbellishData.flags &= ~NS_MATHML_STRETCH_DONE; return nsHTMLContainerFrame::DidReflow(aPresContext, aStatus); } // helper function to reflow token elements static nsresult ReflowTokenFor(nsIFrame* aFrame, nsIPresContext* aPresContext, nsHTMLReflowMetrics& aDesiredSize, const nsHTMLReflowState& aReflowState, nsReflowStatus& aStatus); // helper function to palce token elements static nsresult PlaceTokenFor(nsIFrame* aFrame, nsIPresContext* aPresContext, nsIRenderingContext& aRenderingContext, PRBool aPlaceOrigin, nsHTMLReflowMetrics& aDesiredSize); // helper method to reflow a child frame. We are inline frames, and we don't // know our positions until reflow is finished. That's why we ask the // base method not to worry about our position. nsresult ReflowChild(nsIFrame* aKidFrame, nsIPresContext* aPresContext, nsHTMLReflowMetrics& aDesiredSize, const nsHTMLReflowState& aReflowState, nsReflowStatus& aStatus) { return nsHTMLContainerFrame::ReflowChild(aKidFrame, aPresContext, aDesiredSize, aReflowState, 0, 0, NS_FRAME_NO_MOVE_FRAME, aStatus); } // helper function to reflow all children before placing them. // With MathML, we have to reflow all children and use their desired size // information in order to figure out how to lay them. // aDirection = 0 means children will later be laid horizontally // aDirection = 1 means children will later be laid vertically NS_IMETHOD ReflowChildren(PRInt32 aDirection, nsIPresContext* aPresContext, nsHTMLReflowMetrics& aDesiredSize, const nsHTMLReflowState& aReflowState, nsReflowStatus& aStatus); // helper function to fire a Stretch command on all children, // Note that if the container is embellished, the stretch is not fired // on its embellished child. It is the responsibility of the parent // of the embellished container to fire a stretch that is then passed // onto the embellished child. // If an embellished container doesn't have a parent that will fire // a stretch, it will do it itself (see FinalizeReflow). NS_IMETHOD StretchChildren(nsIPresContext* aPresContext, nsIRenderingContext& aRenderingContext, nsStretchDirection aStretchDirection, nsStretchMetrics& aContainerSize); // helper method to complete the post-reflow hook and ensure that embellished // operators don't terminate their Reflow without receiving a Stretch command. NS_IMETHOD FinalizeReflow(PRInt32 aDirection, nsIPresContext* aPresContext, nsIRenderingContext& aRenderingContext, nsHTMLReflowMetrics& aDesiredSize); // helper method to alter the style contexts of subscript/superscript elements // XXX this is pretty much a hack until the content model caters for MathML and // the style system has some provisions for MathML NS_IMETHOD InsertScriptLevelStyleContext(nsIPresContext* aPresContext); // helper to check if a frame is an embellished container static PRBool IsEmbellishOperator(nsIFrame* aFrame); // helper methods for processing empty MathML frames (with whitespace only) static PRBool IsOnlyWhitespace(nsIFrame* aFrame); static void ReflowEmptyChild(nsIPresContext* aPresContext, nsIFrame* aFrame); // helper methods to facilitate getting/setting the bounding metrics static nsresult GetBoundingMetricsFor(nsIFrame* aFrame, nsBoundingMetrics& aBoundingMetrics) { aBoundingMetrics.Clear(); nsIMathMLFrame* aMathMLFrame = nsnull; nsresult rv = aFrame->QueryInterface(nsIMathMLFrame::GetIID(), (void**)&aMathMLFrame); if (NS_SUCCEEDED(rv) && aMathMLFrame) { aMathMLFrame->GetBoundingMetrics(aBoundingMetrics); return NS_OK; } // if we reach here, aFrame is not a MathML frame, let the caller know that printf("GetBoundingMetrics() failed!! ...\n"); /* getchar(); */ return NS_ERROR_FAILURE; } static nsresult SetBoundingMetricsFor(nsIFrame* aFrame, nsBoundingMetrics& aBoundingMetrics) { nsIMathMLFrame* aMathMLFrame = nsnull; nsresult rv = aFrame->QueryInterface(nsIMathMLFrame::GetIID(), (void**)&aMathMLFrame); if (NS_SUCCEEDED(rv) && aMathMLFrame) { aMathMLFrame->SetBoundingMetrics(aBoundingMetrics); return NS_OK; } // if we reach here, aFrame is not a MathML frame, let the caller know that printf("SetBoundingMetrics() failed!! ...\n"); /* getchar(); */ return NS_ERROR_FAILURE; } // helper methods for getting sup/subdrop's from a child static void GetSubDropFromChild (nsIPresContext* aPresContext, nsIFrame* aChild, nscoord& aSubDrop) { const nsStyleFont *font; aChild->GetStyleData(eStyleStruct_Font, (const nsStyleStruct *&)font); nsCOMPtr fm; aPresContext->GetMetricsFor(font->mFont, getter_AddRefs(fm)); GetSubDrop (fm, aSubDrop); } static void GetSupDropFromChild (nsIPresContext* aPresContext, nsIFrame* aChild, nscoord& aSupDrop) { const nsStyleFont *font; aChild->GetStyleData(eStyleStruct_Font, (const nsStyleStruct *&)font); nsCOMPtr fm; aPresContext->GetMetricsFor(font->mFont, getter_AddRefs(fm)); GetSupDrop (fm, aSupDrop); } // 2 levels of subscript shifts static void GetSubScriptShifts (nsIFontMetrics *fm, nscoord& aSubScriptShift1, nscoord& aSubScriptShift2) { // XXX for now an alias for GetSubscriptOffset fm->GetSubscriptOffset (aSubScriptShift1); aSubScriptShift2 = aSubScriptShift1 = NSToCoordRound(0.5f * aSubScriptShift1); } // 3 levels of superscript shifts static void GetSupScriptShifts (nsIFontMetrics *fm, nscoord& aSupScriptShift1, nscoord& aSupScriptShift2, nscoord& aSupScriptShift3) { // XXX for now an alias for GetSupscriptOffset fm->GetSuperscriptOffset (aSupScriptShift1); aSupScriptShift2 = aSupScriptShift3 = aSupScriptShift1 = NSToCoordRound(0.75f * aSupScriptShift1); } // these are TeX specific params not found in ordinary fonts static void GetSubDrop (nsIFontMetrics *fm, nscoord& aSubDrop) { nscoord xHeight; fm->GetXHeight (xHeight); aSubDrop = NSToCoordRound(0.3f * xHeight); } static void GetSupDrop (nsIFontMetrics *fm, nscoord& aSupDrop) { nscoord xHeight; fm->GetXHeight (xHeight); aSupDrop = NSToCoordRound(0.3f * xHeight); } protected: PRInt32 mScriptLevel; // Relevant to nested frames within: msub, msup, msubsup, munder, // mover, munderover, mmultiscripts, mfrac, mroot, mtable. PRBool mDisplayStyle; // displaystyle="false" is intended to slightly alter how the // rendering is done in inline mode. PRBool mCompressed; // for compatibility with TeX rendering // for internal use only, cannot be set by the user. nscoord mScriptSpace; // scriptspace from TeX for extra spacing after sup/subscript // = 0.5pt in plain TeX nsEmbellishData mEmbellishData; // information about a container that is an embellished operator nsBoundingMetrics mBoundingMetrics; // Metrics that _exactly_ enclose the text of the frame nsPoint mReference; // Reference point of the frame: mReference.y is the baseline virtual PRIntn GetSkipSides() const { return 0; } }; // XXX hack until the content model caters for MathML and the style system // has some provisions for MathML class nsMathMLWrapperFrame : public nsMathMLContainerFrame { public: friend nsresult NS_NewMathMLWrapperFrame(nsIPresShell* aPresShell, nsIFrame** aNewFrame); NS_IMETHOD Reflow(nsIPresContext* aPresContext, nsHTMLReflowMetrics& aDesiredSize, const nsHTMLReflowState& aReflowState, nsReflowStatus& aStatus); NS_IMETHOD Place(nsIPresContext* aPresContext, nsIRenderingContext& aRenderingContext, PRBool aPlaceOrigin, nsHTMLReflowMetrics& aDesiredSize); protected: nsMathMLWrapperFrame(); virtual ~nsMathMLWrapperFrame(); virtual PRIntn GetSkipSides() const { return 0; } }; #endif /* nsMathMLContainerFrame_h___ */