1 files changed, 348 insertions, 0 deletions
diff --git a/layout/generic/ReflowOutput.h b/layout/generic/ReflowOutput.h
new file mode 100644
index 000000000..9877ed6fa
--- /dev/null
+++ b/layout/generic/ReflowOutput.h
@@ -0,0 +1,348 @@
+/* -*- 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/. */
+
+/* struct containing the output from nsIFrame::Reflow */
+
+#ifndef mozilla_ReflowOutput_h
+#define mozilla_ReflowOutput_h
+
+#include "mozilla/WritingModes.h"
+#include "nsBoundingMetrics.h"
+#include "nsRect.h"
+
+//----------------------------------------------------------------------
+
+namespace mozilla {
+struct ReflowInput;
+} // namespace mozilla
+
+// Option flags
+#define NS_REFLOW_CALC_BOUNDING_METRICS  0x0001
+
+/**
+ * When we store overflow areas as an array of scrollable and visual
+ * overflow, we use these indices.
+ *
+ * eOverflowType_LENGTH is needed (for gcc 4.5.*, at least) to ensure
+ * that 2 is a valid value of nsOverflowType for use in
+ * NS_FOR_FRAME_OVERFLOW_TYPES.
+ */
+enum nsOverflowType { eVisualOverflow, eScrollableOverflow,
+                      eOverflowType_LENGTH };
+
+#define NS_FOR_FRAME_OVERFLOW_TYPES(var_)                                     \
+  for (nsOverflowType var_ = nsOverflowType(0); var_ < 2;                     \
+       var_ = nsOverflowType(var_ + 1))
+
+struct nsOverflowAreas {
+private:
+  nsRect mRects[2];
+public:
+  nsRect& Overflow(size_t aIndex) {
+    NS_ASSERTION(aIndex < 2, "index out of range");
+    return mRects[aIndex];
+  }
+  const nsRect& Overflow(size_t aIndex) const {
+    NS_ASSERTION(aIndex < 2, "index out of range");
+    return mRects[aIndex];
+  }
+
+  nsRect& VisualOverflow() { return mRects[eVisualOverflow]; }
+  const nsRect& VisualOverflow() const { return mRects[eVisualOverflow]; }
+
+  nsRect& ScrollableOverflow() { return mRects[eScrollableOverflow]; }
+  const nsRect& ScrollableOverflow() const { return mRects[eScrollableOverflow]; }
+
+  nsOverflowAreas() {
+    // default-initializes to zero due to nsRect's default constructor
+  }
+
+  nsOverflowAreas(const nsRect& aVisualOverflow,
+                  const nsRect& aScrollableOverflow)
+  {
+    mRects[eVisualOverflow] = aVisualOverflow;
+    mRects[eScrollableOverflow] = aScrollableOverflow;
+  }
+
+  nsOverflowAreas(const nsOverflowAreas& aOther) {
+    *this = aOther;
+  }
+
+  nsOverflowAreas& operator=(const nsOverflowAreas& aOther) {
+    mRects[0] = aOther.mRects[0];
+    mRects[1] = aOther.mRects[1];
+    return *this;
+  }
+
+  bool operator==(const nsOverflowAreas& aOther) const {
+    // Scrollable overflow is a point-set rectangle and visual overflow
+    // is a pixel-set rectangle.
+    return VisualOverflow().IsEqualInterior(aOther.VisualOverflow()) &&
+           ScrollableOverflow().IsEqualEdges(aOther.ScrollableOverflow());
+  }
+
+  bool operator!=(const nsOverflowAreas& aOther) const {
+    return !(*this == aOther);
+  }
+
+  nsOverflowAreas operator+(const nsPoint& aPoint) const {
+    nsOverflowAreas result(*this);
+    result += aPoint;
+    return result;
+  }
+
+  nsOverflowAreas& operator+=(const nsPoint& aPoint) {
+    mRects[0] += aPoint;
+    mRects[1] += aPoint;
+    return *this;
+  }
+
+  void Clear() {
+    mRects[0].SetRect(0, 0, 0, 0);
+    mRects[1].SetRect(0, 0, 0, 0);
+  }
+
+  // Mutates |this| by unioning both overflow areas with |aOther|.
+  void UnionWith(const nsOverflowAreas& aOther);
+
+  // Mutates |this| by unioning both overflow areas with |aRect|.
+  void UnionAllWith(const nsRect& aRect);
+
+  // Mutates |this| by setting both overflow areas to |aRect|.
+  void SetAllTo(const nsRect& aRect);
+};
+
+/**
+ * An nsCollapsingMargin represents a vertical collapsing margin between
+ * blocks as described in section 8.3.1 of CSS2,
+ * <URL: http://www.w3.org/TR/REC-CSS2/box.html#collapsing-margins >.
+ *
+ * All adjacent vertical margins collapse, and the resulting margin is
+ * the sum of the largest positive margin included and the smallest (most
+ * negative) negative margin included.
+ */
+struct nsCollapsingMargin {
+  private:
+    nscoord mMostPos;  // the largest positive margin included
+    nscoord mMostNeg;  // the smallest negative margin included
+
+  public:
+    nsCollapsingMargin()
+        : mMostPos(0),
+          mMostNeg(0)
+      {
+      }
+
+    nsCollapsingMargin(const nsCollapsingMargin& aOther)
+        : mMostPos(aOther.mMostPos),
+          mMostNeg(aOther.mMostNeg)
+      {
+      }
+
+    bool operator==(const nsCollapsingMargin& aOther)
+      {
+        return mMostPos == aOther.mMostPos &&
+          mMostNeg == aOther.mMostNeg;
+      }
+
+    bool operator!=(const nsCollapsingMargin& aOther)
+      {
+        return !(*this == aOther);
+      }
+
+    nsCollapsingMargin& operator=(const nsCollapsingMargin& aOther)
+      {
+        mMostPos = aOther.mMostPos;
+        mMostNeg = aOther.mMostNeg;
+        return *this;
+      }
+
+    void Include(nscoord aCoord)
+      {
+        if (aCoord > mMostPos)
+          mMostPos = aCoord;
+        else if (aCoord < mMostNeg)
+          mMostNeg = aCoord;
+      }
+
+    void Include(const nsCollapsingMargin& aOther)
+      {
+        if (aOther.mMostPos > mMostPos)
+          mMostPos = aOther.mMostPos;
+        if (aOther.mMostNeg < mMostNeg)
+          mMostNeg = aOther.mMostNeg;
+      }
+
+    void Zero()
+      {
+        mMostPos = 0;
+        mMostNeg = 0;
+      }
+
+    bool IsZero() const
+      {
+        return (mMostPos == 0) && (mMostNeg == 0);
+      }
+
+    nscoord get() const
+      {
+        return mMostPos + mMostNeg;
+      }
+};
+
+namespace mozilla {
+
+/**
+ * Reflow metrics used to return the frame's desired size and alignment
+ * information.
+ *
+ * @see #Reflow()
+ */
+class ReflowOutput {
+public:
+  // XXXldb Should |aFlags| generally be passed from parent to child?
+  // Some places do it, and some don't.  |aFlags| should perhaps go away
+  // entirely.
+  // XXX width/height/ascent are OUT parameters and so they shouldn't
+  // have to be initialized, but there are some bad frame classes that
+  // aren't properly setting them when returning from Reflow()...
+  explicit ReflowOutput(mozilla::WritingMode aWritingMode, uint32_t aFlags = 0)
+    : mISize(0)
+    , mBSize(0)
+    , mBlockStartAscent(ASK_FOR_BASELINE)
+    , mFlags(aFlags)
+    , mWritingMode(aWritingMode)
+  {}
+
+  explicit ReflowOutput(const ReflowInput& aState, uint32_t aFlags = 0);
+
+  // ISize and BSize are logical-coordinate dimensions:
+  // ISize is the size in the writing mode's inline direction (which equates to
+  // width in horizontal writing modes, height in vertical ones), and BSize is
+  // the size in the block-progression direction.
+  nscoord ISize(mozilla::WritingMode aWritingMode) const {
+    NS_ASSERTION(!aWritingMode.IsOrthogonalTo(mWritingMode),
+                 "mismatched writing mode");
+    return mISize;
+  }
+  nscoord BSize(mozilla::WritingMode aWritingMode) const {
+    NS_ASSERTION(!aWritingMode.IsOrthogonalTo(mWritingMode),
+                 "mismatched writing mode");
+    return mBSize;
+  }
+  mozilla::LogicalSize Size(mozilla::WritingMode aWritingMode) const {
+    NS_ASSERTION(!aWritingMode.IsOrthogonalTo(mWritingMode),
+                 "mismatched writing mode");
+    return mozilla::LogicalSize(aWritingMode, mISize, mBSize);
+  }
+
+  nscoord& ISize(mozilla::WritingMode aWritingMode) {
+    NS_ASSERTION(!aWritingMode.IsOrthogonalTo(mWritingMode),
+                 "mismatched writing mode");
+    return mISize;
+  }
+  nscoord& BSize(mozilla::WritingMode aWritingMode) {
+    NS_ASSERTION(!aWritingMode.IsOrthogonalTo(mWritingMode),
+                 "mismatched writing mode");
+    return mBSize;
+  }
+
+  // Set inline and block size from a LogicalSize, converting to our
+  // writing mode as necessary.
+  void SetSize(mozilla::WritingMode aWM, mozilla::LogicalSize aSize)
+  {
+    mozilla::LogicalSize convertedSize = aSize.ConvertTo(mWritingMode, aWM);
+    mBSize = convertedSize.BSize(mWritingMode);
+    mISize = convertedSize.ISize(mWritingMode);
+  }
+
+  // Set both inline and block size to zero -- no need for a writing mode!
+  void ClearSize()
+  {
+    mISize = mBSize = 0;
+  }
+
+  // Width and Height are physical dimensions, independent of writing mode.
+  // Accessing these is slightly more expensive than accessing the logical
+  // dimensions (once vertical writing mode support is enabled); as far as
+  // possible, client code should work purely with logical dimensions.
+  nscoord Width() const { return mWritingMode.IsVertical() ? mBSize : mISize; }
+  nscoord Height() const { return mWritingMode.IsVertical() ? mISize : mBSize; }
+
+  // It's only meaningful to consider "ascent" on the block-start side of the
+  // frame, so no need to pass a writing mode argument
+  nscoord BlockStartAscent() const
+  {
+    return mBlockStartAscent;
+  }
+
+  nscoord& Width() { return mWritingMode.IsVertical() ? mBSize : mISize; }
+  nscoord& Height() { return mWritingMode.IsVertical() ? mISize : mBSize; }
+
+  nsSize PhysicalSize()
+  {
+    return Size(mWritingMode).GetPhysicalSize(mWritingMode);
+  }
+
+  void SetBlockStartAscent(nscoord aAscent)
+  {
+    mBlockStartAscent = aAscent;
+  }
+
+  enum { ASK_FOR_BASELINE = nscoord_MAX };
+
+  // Metrics that _exactly_ enclose the text to allow precise MathML placements.
+  // If the NS_REFLOW_CALC_BOUNDING_METRICS flag is set, then the caller is 
+  // requesting that you also compute additional details about your inner
+  // bounding box and italic correction. For example, the bounding box of
+  // msup is the smallest rectangle that _exactly_ encloses both the text
+  // of the base and the text of the superscript.
+  nsBoundingMetrics mBoundingMetrics;  // [OUT]
+
+  // Carried out block-end margin values. This is the collapsed
+  // (generational) block-end margin value.
+  nsCollapsingMargin mCarriedOutBEndMargin;
+
+  // For frames that have content that overflow their content area
+  // (HasOverflowAreas() is true) these rectangles represent the total
+  // area of the frame including visible overflow, i.e., don't include
+  // overflowing content that is hidden.  The rects are in the local
+  // coordinate space of the frame, and should be at least as big as the
+  // desired size. If there is no content that overflows, then the
+  // overflow area is identical to the desired size and should be {0, 0,
+  // width, height}.
+  nsOverflowAreas mOverflowAreas;
+
+  nsRect& VisualOverflow()
+    { return mOverflowAreas.VisualOverflow(); }
+  const nsRect& VisualOverflow() const
+    { return mOverflowAreas.VisualOverflow(); }
+  nsRect& ScrollableOverflow()
+    { return mOverflowAreas.ScrollableOverflow(); }
+  const nsRect& ScrollableOverflow() const
+    { return mOverflowAreas.ScrollableOverflow(); }
+
+  // Set all of mOverflowAreas to (0, 0, width, height).
+  void SetOverflowAreasToDesiredBounds();
+
+  // Union all of mOverflowAreas with (0, 0, width, height).
+  void UnionOverflowAreasWithDesiredBounds();
+
+  mozilla::WritingMode GetWritingMode() const { return mWritingMode; }
+
+private:
+  nscoord mISize, mBSize; // [OUT] desired width and height (border-box)
+  nscoord mBlockStartAscent; // [OUT] baseline (in Block direction), or ASK_FOR_BASELINE
+
+public:
+  uint32_t mFlags;
+
+private:
+  mozilla::WritingMode mWritingMode;
+};
+
+} // mozilla namespace
+
+#endif // mozilla_ReflowOutput_h