Mozilla/mozilla/layout/mathml/base/src/nsMathMLContainerFrame.h
rbs%maths.uq.edu.au 7221d01a37 [not part of default build] Header that should have gone with the other files
git-svn-id: svn://10.0.0.236/trunk@70047 18797224-902f-48f8-a5cc-f745e15eee43
2000-05-16 13:29:37 +00:00

518 lines
18 KiB
C++

/*
* 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 <rbs@maths.uq.edu.au>
* David J. Fiddes <D.J.Fiddes@hw.ac.uk>
* Shyjan Mahamud <mahamud@cs.cmu.edu> (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"
#include "nsCSSValue.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
* <tag>base arguments</tag>, 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_DECL_ISUPPORTS
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,
nsBoundingMetrics& aContainerSize,
nsHTMLReflowMetrics& aDesiredStretchSize);
#if 0
NS_IMETHOD
GetDesiredStretchSize(nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
nsBoundingMetrics& 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(nsPresentationData& aPresentationData);
NS_IMETHOD
SetPresentationData(const nsPresentationData& aPresentationData);
NS_IMETHOD
UpdatePresentationData(PRInt32 aScriptLevelIncrement,
PRBool aDisplayStyle,
PRBool aCompressed);
NS_IMETHOD
UpdatePresentationDataFromChildAt(PRInt32 aIndex,
PRInt32 aScriptLevelIncrement,
PRBool aDisplayStyle,
PRBool aCompressed);
// 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_IMETHODIMP
ReflowDirtyChild(nsIPresShell* aPresShell,
nsIFrame* aChild);
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);
}
#if defined(NS_DEBUG) && defined(SHOW_BOUNDING_BOX)
NS_IMETHOD
Paint(nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
const nsRect& aDirtyRect,
nsFramePaintLayer aWhichLayer);
#endif
// error handlers to report than an error (typically invalid markup)
// was encountered during reflow. By default the user will see the
// Unicode REPLACEMENT CHAR U+FFFD at the spot where the error was
// encountered.
virtual nsresult
ReflowError(nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
nsHTMLReflowMetrics& aDesiredSize);
virtual nsresult
PaintError(nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
const nsRect& aDirtyRect,
nsFramePaintLayer aWhichLayer);
// helper function to reflow token elements
static nsresult
ReflowTokenFor(nsIFrame* aFrame,
nsIPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus);
// helper function to place 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 method to complete the post-reflow hook and ensure that embellished
// operators don't terminate their Reflow without receiving a Stretch command.
virtual nsresult
FinalizeReflow(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
virtual nsresult
InsertScriptLevelStyleContext(nsIPresContext* aPresContext);
// helper to give a style context suitable for doing the stretching to the
// MathMLChar. Frame classes that use this should make the extra style contexts
// accessible to the Style System via Get/Set AdditionalStyleContext.
// return true if the char is a mutable char
static PRBool
ResolveMathMLCharStyle(nsIPresContext* aPresContext,
nsIContent* aContent,
nsIStyleContext* aParenStyleContext,
nsMathMLChar* aMathMLChar);
// helper to find the smallest font-size on a tree so that we don't insert
// scriptlevel fonts that lead to unreadable results on deeper nodes below us.
// XXX expensive recursive function, need something better, with cache
static PRInt32
FindSmallestFontSizeFor(nsIPresContext* aPresContext,
nsIFrame* aFrame);
// 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 void
ReflowEmptyChild(nsIPresContext* aPresContext,
nsIFrame* aFrame);
static PRBool
IsOnlyWhitespace(nsIFrame* aFrame);
// helper method to facilitate getting the reflow and bounding metrics
// IMPORTANT: This function is only meant to be called in Place() methods
// where it is assumed that the frame's rect is still acting as place holder
// for the frame's ascent and descent information
static void
GetReflowAndBoundingMetricsFor(nsIFrame* aFrame,
nsHTMLReflowMetrics& aReflowMetrics,
nsBoundingMetrics& aBoundingMetrics);
// helper to check if a content has an attribute. If content is nsnull or if
// the attribute is not there, check if the attribute is on the mstyle hierarchy
// @return NS_CONTENT_ATTR_HAS_VALUE --if attribute has non-empty value, attr="value"
// NS_CONTENT_ATTR_NO_VALUE --if attribute has empty value, attr=""
// NS_CONTENT_ATTR_NOT_THERE --if attribute is not there
static nsresult
GetAttribute(nsIContent* aContent,
nsIFrame* aMathMLmstyleFrame,
nsIAtom* aAttributeAtom,
nsString& aValue);
// utilities to parse and retrieve numeric values in CSS units
// All values are stored in twips.
static PRBool
ParseNumericValue(nsString& aString,
nsCSSValue& aCSSValue);
static nscoord
CalcLength(nsIPresContext* aPresContext,
nsIStyleContext* aStyleContext,
const nsCSSValue& aCSSValue);
static PRBool
ParseNamedSpaceValue(nsIFrame* aMathMLmstyleFrame,
nsString& aString,
nsCSSValue& aCSSValue);
// 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<nsIFontMetrics> 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<nsIFontMetrics> fm;
aPresContext->GetMetricsFor(font->mFont, getter_AddRefs(fm));
GetSupDrop (fm, aSupDrop);
}
static void
GetSkewCorrectionFromChild (nsIPresContext* aPresContext,
nsIFrame* aChild,
nscoord& aSkewCorrection)
{
// default is 0
// individual classes should over-ride this method if necessary
aSkewCorrection = 0;
}
// 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(50.000f/430.556f * xHeight);
}
static void
GetSupDrop (nsIFontMetrics *fm, nscoord& aSupDrop)
{
nscoord xHeight;
fm->GetXHeight (xHeight);
aSupDrop = NSToCoordRound(386.108f/430.556f * xHeight);
}
static void
GetSubShifts (nsIFontMetrics *fm,
nscoord& aSubShift1,
nscoord& aSubShift2)
{
nscoord xHeight = 0;
fm->GetXHeight (xHeight);
aSubShift1 = NSToCoordRound (150.000f/430.556f * xHeight);
aSubShift2 = NSToCoordRound (247.217f/430.556f * xHeight);
}
static void
GetSupShifts (nsIFontMetrics *fm,
nscoord& aSupShift1,
nscoord& aSupShift2,
nscoord& aSupShift3)
{
nscoord xHeight = 0;
fm->GetXHeight (xHeight);
aSupShift1 = NSToCoordRound (412.892f/430.556f * xHeight);
aSupShift2 = NSToCoordRound (362.892f/430.556f * xHeight);
aSupShift3 = NSToCoordRound (288.889f/430.556f * xHeight);
}
static void
GetNumeratorShifts (nsIFontMetrics *fm,
nscoord& numShift1,
nscoord& numShift2,
nscoord& numShift3)
{
nscoord xHeight = 0;
fm->GetXHeight (xHeight);
numShift1 = NSToCoordRound (676.508f/430.556f * xHeight);
numShift2 = NSToCoordRound (393.732f/430.556f * xHeight);
numShift3 = NSToCoordRound (443.731f/430.556f * xHeight);
}
static void
GetDenominatorShifts (nsIFontMetrics *fm,
nscoord& denShift1,
nscoord& denShift2)
{
nscoord xHeight = 0;
fm->GetXHeight (xHeight);
denShift1 = NSToCoordRound (685.951f/430.556f * xHeight);
denShift2 = NSToCoordRound (344.841f/430.556f * xHeight);
}
static void
GetAxisHeight (nsIFontMetrics *fm,
nscoord& axisHeight)
{
fm->GetXHeight (axisHeight);
axisHeight = NSToCoordRound (250.000f/430.556f * axisHeight);
}
static void
GetBigOpSpacings (nsIFontMetrics *fm,
nscoord& bigOpSpacing1,
nscoord& bigOpSpacing2,
nscoord& bigOpSpacing3,
nscoord& bigOpSpacing4,
nscoord& bigOpSpacing5)
{
nscoord xHeight = 0;
fm->GetXHeight (xHeight);
bigOpSpacing1 = NSToCoordRound (111.111f/430.556f * xHeight);
bigOpSpacing2 = NSToCoordRound (166.667f/430.556f * xHeight);
bigOpSpacing3 = NSToCoordRound (200.000f/430.556f * xHeight);
bigOpSpacing4 = NSToCoordRound (600.000f/430.556f * xHeight);
bigOpSpacing5 = NSToCoordRound (100.000f/430.556f * xHeight);
}
static void
GetRuleThickness(nsIFontMetrics* fm,
nscoord& ruleThickness)
{
nscoord xHeight;
fm->GetXHeight (xHeight);
ruleThickness = NSToCoordRound (40.000f/430.556f * xHeight);
}
// Some parameters are not accurately obtained using the x-height.
// Here are some slower variants to obtain the desired metrics
// by actually measuring some characters
static void
GetRuleThickness(nsIRenderingContext& aRenderingContext,
nsIFontMetrics* aFontMetrics,
nscoord& aRuleThickness);
static void
GetAxisHeight(nsIRenderingContext& aRenderingContext,
nsIFontMetrics* aFontMetrics,
nscoord& aAxisHeight);
protected:
// information about the presentation policy of the frame
nsPresentationData mPresentationData;
// information about a container that is an embellished operator
nsEmbellishData mEmbellishData;
// Metrics that _exactly_ enclose the text of the frame
nsBoundingMetrics mBoundingMetrics;
// Reference point of the frame: mReference.y is the baseline
nsPoint mReference;
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);
#if defined(NS_DEBUG) && defined(SHOW_BOUNDING_BOX)
NS_IMETHOD
Paint(nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
const nsRect& aDirtyRect,
nsFramePaintLayer aWhichLayer);
#endif
protected:
nsMathMLWrapperFrame();
virtual ~nsMathMLWrapperFrame();
virtual PRIntn GetSkipSides() const { return 0; }
};
#endif /* nsMathMLContainerFrame_h___ */