The Tor Browser: layout/mathml/nsMathMLFrame.cpp@925c144e1f1f (annotated)

layout/mathml/nsMathMLFrame.cpp@925c144e1f1f (annotated)

layout/mathml/nsMathMLFrame.cpp

Fri, 16 Jan 2015 18:13:44 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Fri, 16 Jan 2015 18:13:44 +0100
branch: TOR_BUG_9701
changeset 14: 925c144e1f1f
permissions: -rw-r--r--

Integrate suggestion from review to improve consistency with existing code.

 /* -*- 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/. */
 #include "nsMathMLFrame.h"
 #include "nsNameSpaceManager.h"
 #include "nsMathMLChar.h"
 #include "nsCSSPseudoElements.h"
 #include "nsMathMLElement.h"
 // used to map attributes into CSS rules
 #include "nsStyleSet.h"
 #include "nsAutoPtr.h"
 #include "nsDisplayList.h"
 #include "nsRenderingContext.h"
 eMathMLFrameType
 nsMathMLFrame::GetMathMLFrameType()
 {
   // see if it is an embellished operator (mapped to 'Op' in TeX)
   if (mEmbellishData.coreFrame)
     return GetMathMLFrameTypeFor(mEmbellishData.coreFrame);
   // if it has a prescribed base, fetch the type from there
   if (mPresentationData.baseFrame)
     return GetMathMLFrameTypeFor(mPresentationData.baseFrame);
   // everything else is treated as ordinary (mapped to 'Ord' in TeX)
   return eMathMLFrameType_Ordinary;
 }
 NS_IMETHODIMP
 nsMathMLFrame::InheritAutomaticData(nsIFrame* aParent)
 {
   mEmbellishData.flags = 0;
   mEmbellishData.coreFrame = nullptr;
   mEmbellishData.direction = NS_STRETCH_DIRECTION_UNSUPPORTED;
   mEmbellishData.leadingSpace = 0;
   mEmbellishData.trailingSpace = 0;
   mPresentationData.flags = 0;
   mPresentationData.baseFrame = nullptr;
   // by default, just inherit the display of our parent
   nsPresentationData parentData;
   GetPresentationDataFrom(aParent, parentData);
 #if defined(DEBUG) && defined(SHOW_BOUNDING_BOX)
   mPresentationData.flags |= NS_MATHML_SHOW_BOUNDING_METRICS;
 #endif
   return NS_OK;
 }
 NS_IMETHODIMP
 nsMathMLFrame::UpdatePresentationData(uint32_t        aFlagsValues,
                                       uint32_t        aWhichFlags)
 {
   NS_ASSERTION(NS_MATHML_IS_COMPRESSED(aWhichFlags),
                "aWhichFlags should only be compression flag");
   if (NS_MATHML_IS_COMPRESSED(aWhichFlags)) {
     // updating the compression flag is allowed
     if (NS_MATHML_IS_COMPRESSED(aFlagsValues)) {
       // 'compressed' means 'prime' style in App. G, TeXbook
       mPresentationData.flags |= NS_MATHML_COMPRESSED;
     }
     // no else. the flag is sticky. it retains its value once it is set
   }
   return NS_OK;
 }
 // Helper to give a style context suitable for doing the stretching of
 // a MathMLChar. Frame classes that use this should ensure that the
 // extra leaf style contexts given to the MathMLChars are accessible to
 // the Style System via the Get/Set AdditionalStyleContext() APIs.
 /* static */ void
 nsMathMLFrame::ResolveMathMLCharStyle(nsPresContext*  aPresContext,
                                       nsIContent*      aContent,
                                       nsStyleContext*  aParentStyleContext,
                                       nsMathMLChar*    aMathMLChar)
 {
   nsCSSPseudoElements::Type pseudoType =
     nsCSSPseudoElements::ePseudo_mozMathAnonymous; // savings
   nsRefPtr<nsStyleContext> newStyleContext;
   newStyleContext = aPresContext->StyleSet()->
     ResolvePseudoElementStyle(aContent->AsElement(), pseudoType,
                               aParentStyleContext, nullptr);
   aMathMLChar->SetStyleContext(newStyleContext);
 }
 /* static */ void
 nsMathMLFrame::GetEmbellishDataFrom(nsIFrame*        aFrame,
                                     nsEmbellishData& aEmbellishData)
 {
   // initialize OUT params
   aEmbellishData.flags = 0;
   aEmbellishData.coreFrame = nullptr;
   aEmbellishData.direction = NS_STRETCH_DIRECTION_UNSUPPORTED;
   aEmbellishData.leadingSpace = 0;
   aEmbellishData.trailingSpace = 0;
   if (aFrame && aFrame->IsFrameOfType(nsIFrame::eMathML)) {
     nsIMathMLFrame* mathMLFrame = do_QueryFrame(aFrame);
     if (mathMLFrame) {
       mathMLFrame->GetEmbellishData(aEmbellishData);
     }
   }
 }
 // helper to get the presentation data of a frame, by possibly walking up
 // the frame hierarchy if we happen to be surrounded by non-MathML frames.
 /* static */ void
 nsMathMLFrame::GetPresentationDataFrom(nsIFrame*           aFrame,
                                        nsPresentationData& aPresentationData,
                                        bool                aClimbTree)
 {
   // initialize OUT params
   aPresentationData.flags = 0;
   aPresentationData.baseFrame = nullptr;
   nsIFrame* frame = aFrame;
   while (frame) {
     if (frame->IsFrameOfType(nsIFrame::eMathML)) {
       nsIMathMLFrame* mathMLFrame = do_QueryFrame(frame);
       if (mathMLFrame) {
         mathMLFrame->GetPresentationData(aPresentationData);
         break;
       }
     }
     // stop if the caller doesn't want to lookup beyond the frame
     if (!aClimbTree) {
       break;
     }
     // stop if we reach the root <math> tag
     nsIContent* content = frame->GetContent();
     NS_ASSERTION(content || !frame->GetParent(), // no assert for the root
                  "dangling frame without a content node");
     if (!content)
       break;
     if (content->Tag() == nsGkAtoms::math) {
       break;
     }
     frame = frame->GetParent();
   }
   NS_WARN_IF_FALSE(frame && frame->GetContent(),
                    "bad MathML markup - could not find the top <math> element");
 }
 /* static */ void
 nsMathMLFrame::GetRuleThickness(nsRenderingContext& aRenderingContext,
                                 nsFontMetrics*      aFontMetrics,
                                 nscoord&             aRuleThickness)
 {
   // get the bounding metrics of the overbar char, the rendering context
   // is assumed to have been set with the font of the current style context
   NS_ASSERTION(aRenderingContext.FontMetrics()->Font().
                Equals(aFontMetrics->Font()),
                "unexpected state");
   nscoord xHeight = aFontMetrics->XHeight();
   char16_t overBar = 0x00AF;
   nsBoundingMetrics bm = aRenderingContext.GetBoundingMetrics(&overBar, 1);
   aRuleThickness = bm.ascent + bm.descent;
   if (aRuleThickness <= 0 || aRuleThickness >= xHeight) {
     // fall-back to the other version
     GetRuleThickness(aFontMetrics, aRuleThickness);
   }
 }
 /* static */ void
 nsMathMLFrame::GetAxisHeight(nsRenderingContext& aRenderingContext,
                              nsFontMetrics*      aFontMetrics,
                              nscoord&             aAxisHeight)
 {
   // get the bounding metrics of the minus sign, the rendering context
   // is assumed to have been set with the font of the current style context
   NS_ASSERTION(aRenderingContext.FontMetrics()->Font().
                Equals(aFontMetrics->Font()),
                "unexpected state");
   nscoord xHeight = aFontMetrics->XHeight();
   char16_t minus = 0x2212; // not '-', but official Unicode minus sign
   nsBoundingMetrics bm = aRenderingContext.GetBoundingMetrics(&minus, 1);
   aAxisHeight = bm.ascent - (bm.ascent + bm.descent)/2;
   if (aAxisHeight <= 0 || aAxisHeight >= xHeight) {
     // fall-back to the other version
     GetAxisHeight(aFontMetrics, aAxisHeight);
   }
 }
 /* static */ nscoord
 nsMathMLFrame::CalcLength(nsPresContext*   aPresContext,
                           nsStyleContext*   aStyleContext,
                           const nsCSSValue& aCSSValue)
 {
   NS_ASSERTION(aCSSValue.IsLengthUnit(), "not a length unit");
   if (aCSSValue.IsFixedLengthUnit()) {
     return aCSSValue.GetFixedLength(aPresContext);
   }
   if (aCSSValue.IsPixelLengthUnit()) {
     return aCSSValue.GetPixelLength();
   }
   nsCSSUnit unit = aCSSValue.GetUnit();
   if (eCSSUnit_EM == unit) {
     const nsStyleFont* font = aStyleContext->StyleFont();
     return NSToCoordRound(aCSSValue.GetFloatValue() * (float)font->mFont.size);
   }
   else if (eCSSUnit_XHeight == unit) {
     nsRefPtr<nsFontMetrics> fm;
     nsLayoutUtils::GetFontMetricsForStyleContext(aStyleContext,
                                                  getter_AddRefs(fm));
     nscoord xHeight = fm->XHeight();
     return NSToCoordRound(aCSSValue.GetFloatValue() * (float)xHeight);
   }
   // MathML doesn't specify other CSS units such as rem or ch
   NS_ERROR("Unsupported unit");
   return 0;
 }
 /* static */ void
 nsMathMLFrame::ParseNumericValue(const nsString&   aString,
                                  nscoord*          aLengthValue,
                                  uint32_t          aFlags,
                                  nsPresContext*    aPresContext,
                                  nsStyleContext*   aStyleContext)
 {
   nsCSSValue cssValue;
   if (!nsMathMLElement::ParseNumericValue(aString, cssValue, aFlags,
                                           aPresContext->Document())) {
     // Invalid attribute value. aLengthValue remains unchanged, so the default
     // length value is used.
     return;
   }
   nsCSSUnit unit = cssValue.GetUnit();
   if (unit == eCSSUnit_Percent || unit == eCSSUnit_Number) {
     // Relative units. A multiple of the default length value is used.
     *aLengthValue = NSToCoordRound(*aLengthValue * (unit == eCSSUnit_Percent ?
                                                     cssValue.GetPercentValue() :
                                                     cssValue.GetFloatValue()));
     return;
   }
   // Absolute units.
   *aLengthValue = CalcLength(aPresContext, aStyleContext, cssValue);
 }
 // ================
 // Utils to map attributes into CSS rules (work-around to bug 69409 which
 // is not scheduled to be fixed anytime soon)
 //
 struct
 nsCSSMapping {
   int32_t        compatibility;
   const nsIAtom* attrAtom;
   const char*    cssProperty;
 };
 #if defined(DEBUG) && defined(SHOW_BOUNDING_BOX)
 class nsDisplayMathMLBoundingMetrics : public nsDisplayItem {
 public:
   nsDisplayMathMLBoundingMetrics(nsDisplayListBuilder* aBuilder,
                                  nsIFrame* aFrame, const nsRect& aRect)
     : nsDisplayItem(aBuilder, aFrame), mRect(aRect) {
     MOZ_COUNT_CTOR(nsDisplayMathMLBoundingMetrics);
   }
 #ifdef NS_BUILD_REFCNT_LOGGING
   virtual ~nsDisplayMathMLBoundingMetrics() {
     MOZ_COUNT_DTOR(nsDisplayMathMLBoundingMetrics);
   }
 #endif
   virtual void Paint(nsDisplayListBuilder* aBuilder,
                      nsRenderingContext* aCtx) MOZ_OVERRIDE;
   NS_DISPLAY_DECL_NAME("MathMLBoundingMetrics", TYPE_MATHML_BOUNDING_METRICS)
 private:
   nsRect    mRect;
 };
 void nsDisplayMathMLBoundingMetrics::Paint(nsDisplayListBuilder* aBuilder,
                                            nsRenderingContext* aCtx)
 {
   aCtx->SetColor(NS_RGB(0,0,255));
   aCtx->DrawRect(mRect + ToReferenceFrame());
 }
 nsresult
 nsMathMLFrame::DisplayBoundingMetrics(nsDisplayListBuilder* aBuilder,
                                       nsIFrame* aFrame, const nsPoint& aPt,
                                       const nsBoundingMetrics& aMetrics,
                                       const nsDisplayListSet& aLists) {
   if (!NS_MATHML_PAINT_BOUNDING_METRICS(mPresentationData.flags))
     return NS_OK;
   nscoord x = aPt.x + aMetrics.leftBearing;
   nscoord y = aPt.y - aMetrics.ascent;
   nscoord w = aMetrics.rightBearing - aMetrics.leftBearing;
   nscoord h = aMetrics.ascent + aMetrics.descent;
   return aLists.Content()->AppendNewToTop(new (aBuilder)
       nsDisplayMathMLBoundingMetrics(aBuilder, this, nsRect(x,y,w,h)));
 }
 #endif
 class nsDisplayMathMLBar : public nsDisplayItem {
 public:
   nsDisplayMathMLBar(nsDisplayListBuilder* aBuilder,
                      nsIFrame* aFrame, const nsRect& aRect)
     : nsDisplayItem(aBuilder, aFrame), mRect(aRect) {
     MOZ_COUNT_CTOR(nsDisplayMathMLBar);
   }
 #ifdef NS_BUILD_REFCNT_LOGGING
   virtual ~nsDisplayMathMLBar() {
     MOZ_COUNT_DTOR(nsDisplayMathMLBar);
   }
 #endif
   virtual void Paint(nsDisplayListBuilder* aBuilder,
                      nsRenderingContext* aCtx) MOZ_OVERRIDE;
   NS_DISPLAY_DECL_NAME("MathMLBar", TYPE_MATHML_BAR)
 private:
   nsRect    mRect;
 };
 void nsDisplayMathMLBar::Paint(nsDisplayListBuilder* aBuilder,
                                nsRenderingContext* aCtx)
 {
   // paint the bar with the current text color
   aCtx->SetColor(mFrame->GetVisitedDependentColor(eCSSProperty_color));
   aCtx->FillRect(mRect + ToReferenceFrame());
 }
 void
 nsMathMLFrame::DisplayBar(nsDisplayListBuilder* aBuilder,
                           nsIFrame* aFrame, const nsRect& aRect,
                           const nsDisplayListSet& aLists) {
   if (!aFrame->StyleVisibility()->IsVisible() || aRect.IsEmpty())
     return;
   aLists.Content()->AppendNewToTop(new (aBuilder)
     nsDisplayMathMLBar(aBuilder, aFrame, aRect));
 }

The Tor Browser / annotate

layout/mathml/nsMathMLFrame.cpp@925c144e1f1f (annotated)

layout/mathml/nsMathMLFrame.cpp