layout/mathml/nsMathMLmfracFrame.h
author Ehsan Akhgari <ehsan@mozilla.com>
Wed, 22 Aug 2012 11:56:38 -0400
changeset 103019 a16372ce30b5f6b747246b01fcd215a4bf3b6342
parent 101928 4587cc2d01545d18cea6d650e725af5751f549ee
child 106753 c4f83d9d8243f3f853a5356188164a5fddee2b5a
permissions -rw-r--r--
Bug 579517 - Part 1: Automated conversion of NSPR numeric types to stdint types in Gecko; r=bsmedberg This patch was generated by a script. Here's the source of the script for future reference: function convert() { echo "Converting $1 to $2..." find . ! -wholename "*nsprpub*" \ ! -wholename "*security/nss*" \ ! -wholename "*/.hg*" \ ! -wholename "obj-ff-dbg*" \ ! -name nsXPCOMCID.h \ ! -name prtypes.h \ -type f \ \( -iname "*.cpp" \ -o -iname "*.h" \ -o -iname "*.c" \ -o -iname "*.cc" \ -o -iname "*.idl" \ -o -iname "*.ipdl" \ -o -iname "*.ipdlh" \ -o -iname "*.mm" \) | \ xargs -n 1 sed -i -e "s/\b$1\b/$2/g" } convert PRInt8 int8_t convert PRUint8 uint8_t convert PRInt16 int16_t convert PRUint16 uint16_t convert PRInt32 int32_t convert PRUint32 uint32_t convert PRInt64 int64_t convert PRUint64 uint64_t convert PRIntn int convert PRUintn unsigned convert PRSize size_t convert PROffset32 int32_t convert PROffset64 int64_t convert PRPtrdiff ptrdiff_t convert PRFloat64 double

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef nsMathMLmfracFrame_h___
#define nsMathMLmfracFrame_h___

#include "nsCOMPtr.h"
#include "nsMathMLContainerFrame.h"

//
// <mfrac> -- form a fraction from two subexpressions 
//

/*
The MathML REC describes:

The <mfrac> element is used for fractions. It can also be used to mark up 
fraction-like objects such as binomial coefficients and Legendre symbols. 
The syntax for <mfrac> is:
  <mfrac> numerator denominator </mfrac>

Attributes of <mfrac>:
     Name                      values                     default 
  linethickness  number [ v-unit ] | thin | medium | thick  1 

E.g., 
linethickness=2 actually means that linethickness=2*DEFAULT_THICKNESS
(DEFAULT_THICKNESS is not specified by MathML, see below.)

The linethickness attribute indicates the thickness of the horizontal
"fraction bar", or "rule", typically used to render fractions. A fraction
with linethickness="0" renders without the bar, and might be used within
binomial coefficients. A linethickness greater than one might be used with
nested fractions. 

In general, the value of linethickness can be a number, as a multiplier
of the default thickness of the fraction bar (the default thickness is
not specified by MathML), or a number with a unit of vertical length (see
Section 2.3.3), or one of the keywords medium (same as 1), thin (thinner
than 1, otherwise up to the renderer), or thick (thicker than 1, otherwise
up to the renderer). 

The <mfrac> element sets displaystyle to "false", or if it was already
false increments scriptlevel by 1, within numerator and denominator.
These attributes are inherited by every element from its rendering 
environment, but can be set explicitly only on the <mstyle> 
element. 
*/

class nsMathMLmfracFrame : public nsMathMLContainerFrame {
public:
  NS_DECL_FRAMEARENA_HELPERS

  friend nsIFrame* NS_NewMathMLmfracFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);

  virtual eMathMLFrameType GetMathMLFrameType();

  virtual nsresult
  MeasureForWidth(nsRenderingContext& aRenderingContext,
                  nsHTMLReflowMetrics& aDesiredSize);

  virtual nsresult
  Place(nsRenderingContext& aRenderingContext,
        bool                 aPlaceOrigin,
        nsHTMLReflowMetrics& aDesiredSize);

  NS_IMETHOD BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                              const nsRect&           aDirtyRect,
                              const nsDisplayListSet& aLists);

  NS_IMETHOD
  TransmitAutomaticData();

  NS_IMETHOD
  UpdatePresentationDataFromChildAt(int32_t         aFirstIndex,
                                    int32_t         aLastIndex,
                                    uint32_t        aFlagsValues,
                                    uint32_t        aFlagsToUpdate);

  // override the base method so that we can deal with the fraction line
  virtual nscoord
  FixInterFrameSpacing(nsHTMLReflowMetrics& aDesiredSize);

  // helper to translate the thickness attribute into a usable form
  static nscoord 
  CalcLineThickness(nsPresContext*  aPresContext,
                    nsStyleContext*  aStyleContext,
                    nsString&        aThicknessAttribute,
                    nscoord          onePixel,
                    nscoord          aDefaultRuleThickness);

protected:
  nsMathMLmfracFrame(nsStyleContext* aContext) : nsMathMLContainerFrame(aContext) {}
  virtual ~nsMathMLmfracFrame();
  
  virtual int GetSkipSides() const { return 0; }

  nsresult PlaceInternal(nsRenderingContext& aRenderingContext,
                         bool                 aPlaceOrigin,
                         nsHTMLReflowMetrics& aDesiredSize,
                         bool                 aWidthOnly);

  // Display a slash
  nsresult DisplaySlash(nsDisplayListBuilder* aBuilder,
                        nsIFrame* aFrame, const nsRect& aRect,
                        nscoord aThickness,
                        const nsDisplayListSet& aLists);

  nsRect        mLineRect;
  nsMathMLChar* mSlashChar;
  nscoord       mLineThickness;
  bool          mIsBevelled;
};

#endif /* nsMathMLmfracFrame_h___ */