Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 383 insertions, 0 deletions

diff --git a/layout/mathml/nsMathMLFrame.cpp b/layout/mathml/nsMathMLFrame.cpp
new file mode 100644
index 0000000000..9a7d94a992
--- /dev/null
+++ b/layout/mathml/nsMathMLFrame.cpp
@@ -0,0 +1,383 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 "gfxContext.h"
+#include "gfxUtils.h"
+#include "mozilla/gfx/2D.h"
+#include "nsCSSValue.h"
+#include "nsLayoutUtils.h"
+#include "nsNameSpaceManager.h"
+#include "nsMathMLChar.h"
+#include "nsCSSPseudoElements.h"
+#include "mozilla/dom/MathMLElement.h"
+#include "gfxMathTable.h"
+#include "nsPresContextInlines.h"
+
+// used to map attributes into CSS rules
+#include "mozilla/ServoStyleSet.h"
+#include "nsDisplayList.h"
+
+using namespace mozilla;
+using namespace mozilla::gfx;
+
+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) ||
+                   NS_MATHML_IS_DTLS_SET(aWhichFlags),
+               "aWhichFlags should only be compression or dtls 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
+  }
+  // These flags determine whether the dtls font feature settings should
+  // be applied.
+  if (NS_MATHML_IS_DTLS_SET(aWhichFlags)) {
+    if (NS_MATHML_IS_DTLS_SET(aFlagsValues)) {
+      mPresentationData.flags |= NS_MATHML_DTLS;
+    } else {
+      mPresentationData.flags &= ~NS_MATHML_DTLS;
+    }
+  }
+  return NS_OK;
+}
+
+/* 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->IsMathMLElement(nsGkAtoms::math)) {
+      break;
+    }
+    frame = frame->GetParent();
+  }
+  NS_WARNING_ASSERTION(
+      frame && frame->GetContent(),
+      "bad MathML markup - could not find the top <math> element");
+}
+
+/* static */
+void nsMathMLFrame::GetRuleThickness(DrawTarget* aDrawTarget,
+                                     nsFontMetrics* aFontMetrics,
+                                     nscoord& aRuleThickness) {
+  nscoord xHeight = aFontMetrics->XHeight();
+  char16_t overBar = 0x00AF;
+  nsBoundingMetrics bm = nsLayoutUtils::AppUnitBoundsOfString(
+      &overBar, 1, *aFontMetrics, aDrawTarget);
+  aRuleThickness = bm.ascent + bm.descent;
+  if (aRuleThickness <= 0 || aRuleThickness >= xHeight) {
+    // fall-back to the other version
+    GetRuleThickness(aFontMetrics, aRuleThickness);
+  }
+}
+
+/* static */
+void nsMathMLFrame::GetAxisHeight(DrawTarget* aDrawTarget,
+                                  nsFontMetrics* aFontMetrics,
+                                  nscoord& aAxisHeight) {
+  RefPtr<gfxFont> mathFont =
+      aFontMetrics->GetThebesFontGroup()->GetFirstMathFont();
+  if (mathFont) {
+    aAxisHeight = mathFont->MathTable()->Constant(
+        gfxMathTable::AxisHeight, aFontMetrics->AppUnitsPerDevPixel());
+    return;
+  }
+
+  nscoord xHeight = aFontMetrics->XHeight();
+  char16_t minus = 0x2212;  // not '-', but official Unicode minus sign
+  nsBoundingMetrics bm = nsLayoutUtils::AppUnitBoundsOfString(
+      &minus, 1, *aFontMetrics, aDrawTarget);
+  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,
+                                  ComputedStyle* aComputedStyle,
+                                  const nsCSSValue& aCSSValue,
+                                  float aFontSizeInflation) {
+  NS_ASSERTION(aCSSValue.IsLengthUnit(), "not a length unit");
+
+  if (aCSSValue.IsPixelLengthUnit()) {
+    return aCSSValue.GetPixelLength();
+  }
+
+  nsCSSUnit unit = aCSSValue.GetUnit();
+
+  if (eCSSUnit_EM == unit) {
+    const nsStyleFont* font = aComputedStyle->StyleFont();
+    return font->mFont.size.ScaledBy(aCSSValue.GetFloatValue()).ToAppUnits();
+  }
+
+  if (eCSSUnit_XHeight == unit) {
+    RefPtr<nsFontMetrics> fm = nsLayoutUtils::GetFontMetricsForComputedStyle(
+        aComputedStyle, aPresContext, aFontSizeInflation);
+    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::GetSubDropFromChild(nsIFrame* aChild, nscoord& aSubDrop,
+                                        float aFontSizeInflation) {
+  RefPtr<nsFontMetrics> fm =
+      nsLayoutUtils::GetFontMetricsForFrame(aChild, aFontSizeInflation);
+  GetSubDrop(fm, aSubDrop);
+}
+
+/* static */
+void nsMathMLFrame::GetSupDropFromChild(nsIFrame* aChild, nscoord& aSupDrop,
+                                        float aFontSizeInflation) {
+  RefPtr<nsFontMetrics> fm =
+      nsLayoutUtils::GetFontMetricsForFrame(aChild, aFontSizeInflation);
+  GetSupDrop(fm, aSupDrop);
+}
+
+/* static */
+void nsMathMLFrame::ParseNumericValue(const nsString& aString,
+                                      nscoord* aLengthValue, uint32_t aFlags,
+                                      nsPresContext* aPresContext,
+                                      ComputedStyle* aComputedStyle,
+                                      float aFontSizeInflation) {
+  nsCSSValue cssValue;
+
+  if (!dom::MathMLElement::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, aComputedStyle, cssValue, aFontSizeInflation);
+}
+
+namespace mozilla {
+#if defined(DEBUG) && defined(SHOW_BOUNDING_BOX)
+class nsDisplayMathMLBoundingMetrics final : public nsDisplayItem {
+ public:
+  nsDisplayMathMLBoundingMetrics(nsDisplayListBuilder* aBuilder,
+                                 nsIFrame* aFrame, const nsRect& aRect)
+      : nsDisplayItem(aBuilder, aFrame), mRect(aRect) {
+    MOZ_COUNT_CTOR(nsDisplayMathMLBoundingMetrics);
+  }
+  MOZ_COUNTED_DTOR_OVERRIDE(nsDisplayMathMLBoundingMetrics)
+
+  virtual void Paint(nsDisplayListBuilder* aBuilder, gfxContext* aCtx) override;
+  NS_DISPLAY_DECL_NAME("MathMLBoundingMetrics", TYPE_MATHML_BOUNDING_METRICS)
+ private:
+  nsRect mRect;
+};
+
+void nsDisplayMathMLBoundingMetrics::Paint(nsDisplayListBuilder* aBuilder,
+                                           gfxContext* aCtx) {
+  DrawTarget* drawTarget = aCtx->GetDrawTarget();
+  Rect r = NSRectToRect(mRect + ToReferenceFrame(),
+                        mFrame->PresContext()->AppUnitsPerDevPixel());
+  ColorPattern blue(ToDeviceColor(Color(0.f, 0.f, 1.f, 1.f)));
+  drawTarget->StrokeRect(r, blue);
+}
+
+void nsMathMLFrame::DisplayBoundingMetrics(nsDisplayListBuilder* aBuilder,
+                                           nsIFrame* aFrame, const nsPoint& aPt,
+                                           const nsBoundingMetrics& aMetrics,
+                                           const nsDisplayListSet& aLists) {
+  if (!NS_MATHML_PAINT_BOUNDING_METRICS(mPresentationData.flags)) return;
+
+  nscoord x = aPt.x + aMetrics.leftBearing;
+  nscoord y = aPt.y - aMetrics.ascent;
+  nscoord w = aMetrics.rightBearing - aMetrics.leftBearing;
+  nscoord h = aMetrics.ascent + aMetrics.descent;
+
+  aLists.Content()->AppendNewToTop<nsDisplayMathMLBoundingMetrics>(
+      aBuilder, aFrame, nsRect(x, y, w, h));
+}
+#endif
+
+class nsDisplayMathMLBar final : public nsPaintedDisplayItem {
+ public:
+  nsDisplayMathMLBar(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame,
+                     const nsRect& aRect)
+      : nsPaintedDisplayItem(aBuilder, aFrame), mRect(aRect) {
+    MOZ_COUNT_CTOR(nsDisplayMathMLBar);
+  }
+  MOZ_COUNTED_DTOR_OVERRIDE(nsDisplayMathMLBar)
+
+  virtual void Paint(nsDisplayListBuilder* aBuilder, gfxContext* aCtx) override;
+  NS_DISPLAY_DECL_NAME("MathMLBar", TYPE_MATHML_BAR)
+
+ private:
+  nsRect mRect;
+};
+
+void nsDisplayMathMLBar::Paint(nsDisplayListBuilder* aBuilder,
+                               gfxContext* aCtx) {
+  // paint the bar with the current text color
+  DrawTarget* drawTarget = aCtx->GetDrawTarget();
+  Rect rect = NSRectToNonEmptySnappedRect(
+      mRect + ToReferenceFrame(), mFrame->PresContext()->AppUnitsPerDevPixel(),
+      *drawTarget);
+  ColorPattern color(ToDeviceColor(
+      mFrame->GetVisitedDependentColor(&nsStyleText::mWebkitTextFillColor)));
+  drawTarget->FillRect(rect, color);
+}
+
+}  // namespace mozilla
+
+void nsMathMLFrame::DisplayBar(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame,
+                               const nsRect& aRect,
+                               const nsDisplayListSet& aLists,
+                               uint32_t aIndex) {
+  if (!aFrame->StyleVisibility()->IsVisible() || aRect.IsEmpty()) return;
+
+  aLists.Content()->AppendNewToTopWithIndex<nsDisplayMathMLBar>(
+      aBuilder, aFrame, aIndex, aRect);
+}
+
+void nsMathMLFrame::GetRadicalParameters(nsFontMetrics* aFontMetrics,
+                                         bool aDisplayStyle,
+                                         nscoord& aRadicalRuleThickness,
+                                         nscoord& aRadicalExtraAscender,
+                                         nscoord& aRadicalVerticalGap) {
+  nscoord oneDevPixel = aFontMetrics->AppUnitsPerDevPixel();
+  RefPtr<gfxFont> mathFont =
+      aFontMetrics->GetThebesFontGroup()->GetFirstMathFont();
+
+  // get the radical rulethickness
+  if (mathFont) {
+    aRadicalRuleThickness = mathFont->MathTable()->Constant(
+        gfxMathTable::RadicalRuleThickness, oneDevPixel);
+  } else {
+    GetRuleThickness(aFontMetrics, aRadicalRuleThickness);
+  }
+
+  // get the leading to be left at the top of the resulting frame
+  if (mathFont) {
+    aRadicalExtraAscender = mathFont->MathTable()->Constant(
+        gfxMathTable::RadicalExtraAscender, oneDevPixel);
+  } else {
+    // This seems more reliable than using aFontMetrics->GetLeading() on
+    // suspicious fonts.
+    nscoord em;
+    GetEmHeight(aFontMetrics, em);
+    aRadicalExtraAscender = nscoord(0.2f * em);
+  }
+
+  // get the clearance between rule and content
+  if (mathFont) {
+    aRadicalVerticalGap = mathFont->MathTable()->Constant(
+        aDisplayStyle ? gfxMathTable::RadicalDisplayStyleVerticalGap
+                      : gfxMathTable::RadicalVerticalGap,
+        oneDevPixel);
+  } else {
+    // Rule 11, App. G, TeXbook
+    aRadicalVerticalGap =
+        aRadicalRuleThickness +
+        (aDisplayStyle ? aFontMetrics->XHeight() : aRadicalRuleThickness) / 4;
+  }
+}