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/* -*- 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
/* struct containing the output from nsIFrame::Reflow */
#ifndef mozilla_ReflowOutput_h
#define mozilla_ReflowOutput_h
#include "mozilla/EnumeratedRange.h"
#include "mozilla/WritingModes.h"
#include "nsBoundingMetrics.h"
#include "nsRect.h"
//----------------------------------------------------------------------
namespace mozilla {
struct ReflowInput;
enum class OverflowType : uint8_t { Ink, Scrollable };
constexpr auto AllOverflowTypes() {
return mozilla::MakeInclusiveEnumeratedRange(OverflowType::Ink,
OverflowType::Scrollable);
}
struct OverflowAreas {
public:
nsRect& InkOverflow() { return mInk; }
const nsRect& InkOverflow() const { return mInk; }
nsRect& ScrollableOverflow() { return mScrollable; }
const nsRect& ScrollableOverflow() const { return mScrollable; }
nsRect& Overflow(OverflowType aType) {
return aType == OverflowType::Ink ? InkOverflow() : ScrollableOverflow();
}
const nsRect& Overflow(OverflowType aType) const {
return aType == OverflowType::Ink ? InkOverflow() : ScrollableOverflow();
}
OverflowAreas() = default;
OverflowAreas(const nsRect& aInkOverflow, const nsRect& aScrollableOverflow)
: mInk(aInkOverflow), mScrollable(aScrollableOverflow) {}
bool operator==(const OverflowAreas& aOther) const {
// Scrollable overflow is a point-set rectangle and ink overflow
// is a pixel-set rectangle.
return InkOverflow().IsEqualInterior(aOther.InkOverflow()) &&
ScrollableOverflow().IsEqualEdges(aOther.ScrollableOverflow());
}
bool operator!=(const OverflowAreas& aOther) const {
return !(*this == aOther);
}
OverflowAreas operator+(const nsPoint& aPoint) const {
OverflowAreas result(*this);
result += aPoint;
return result;
}
OverflowAreas& operator+=(const nsPoint& aPoint) {
mInk += aPoint;
mScrollable += aPoint;
return *this;
}
void Clear() { SetAllTo(nsRect()); }
// Mutates |this| by unioning both overflow areas with |aOther|.
void UnionWith(const OverflowAreas& 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);
// Applies overflow clipping (for e.g. overflow: clip) as needed to both our
// overflow rects.
void ApplyClipping(const nsRect& aBounds, PhysicalAxes aClipAxes,
const nsSize& aOverflowMargin) {
ApplyOverflowClippingOnRect(InkOverflow(), aBounds, aClipAxes,
aOverflowMargin);
ApplyOverflowClippingOnRect(ScrollableOverflow(), aBounds, aClipAxes,
aOverflowMargin);
}
// Gets the overflow clipping rect for a given element given a rect to clip,
// the frame bounds, a set of axes, and the overflow margin.
static nsRect GetOverflowClipRect(const nsRect& aRectToClip,
const nsRect& aBounds,
PhysicalAxes aClipAxes,
const nsSize& aOverflowMargin);
// Applies the overflow clipping to a given overflow rect, given the frame
// bounds, and the physical axes on which to apply the overflow clip.
static void ApplyOverflowClippingOnRect(nsRect& aOverflowRect,
const nsRect& aBounds,
PhysicalAxes aClipAxes,
const nsSize& aOverflowMargin);
private:
nsRect mInk;
nsRect mScrollable;
};
} // namespace mozilla
/**
* An nsCollapsingMargin represents a vertical collapsing margin between
* blocks as described in section 8.3.1 of CSS2,
*
* 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) = default;
bool operator==(const nsCollapsingMargin& aOther) const {
return mMostPos == aOther.mMostPos && mMostNeg == aOther.mMostNeg;
}
bool operator!=(const nsCollapsingMargin& aOther) const {
return !(*this == aOther);
}
nsCollapsingMargin& operator=(const nsCollapsingMargin& aOther) = default;
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 {
/**
* ReflowOutput is initialized by a parent frame as a parameter passing to
* Reflow() to allow a child frame to return its desired size and alignment
* information.
*
* ReflowOutput's constructor usually takes a parent frame's WritingMode (or
* ReflowInput) because it is more convenient for the parent frame to use the
* stored Size() after reflowing the child frame. However, it can actually
* accept any WritingMode (or ReflowInput) because SetSize() knows how to
* convert a size in any writing mode to the stored writing mode.
*
* @see nsIFrame::Reflow() for more information.
*/
class ReflowOutput {
public:
explicit ReflowOutput(mozilla::WritingMode aWritingMode)
: mSize(aWritingMode), mWritingMode(aWritingMode) {}
// A convenient constructor to get WritingMode in ReflowInput.
explicit ReflowOutput(const ReflowInput& aReflowInput);
nscoord ISize(mozilla::WritingMode aWritingMode) const {
return mSize.ISize(aWritingMode);
}
nscoord BSize(mozilla::WritingMode aWritingMode) const {
return mSize.BSize(aWritingMode);
}
mozilla::LogicalSize Size(mozilla::WritingMode aWritingMode) const {
return mSize.ConvertTo(aWritingMode, mWritingMode);
}
nscoord& ISize(mozilla::WritingMode aWritingMode) {
return mSize.ISize(aWritingMode);
}
nscoord& BSize(mozilla::WritingMode aWritingMode) {
return mSize.BSize(aWritingMode);
}
// Set inline and block size from a LogicalSize, converting to our
// writing mode as necessary.
void SetSize(mozilla::WritingMode aWM, mozilla::LogicalSize aSize) {
mSize = aSize.ConvertTo(mWritingMode, aWM);
}
// Set both inline and block size to zero -- no need for a writing mode!
void ClearSize() { mSize.SizeTo(mWritingMode, 0, 0); }
// Width and Height are physical dimensions, independent of writing mode.
// Accessing these is slightly more expensive than accessing the logical
// dimensions; as far as possible, client code should work purely with logical
// dimensions.
nscoord Width() const { return mSize.Width(mWritingMode); }
nscoord Height() const { return mSize.Height(mWritingMode); }
nscoord& Width() {
return mWritingMode.IsVertical() ? mSize.BSize(mWritingMode)
: mSize.ISize(mWritingMode);
}
nscoord& Height() {
return mWritingMode.IsVertical() ? mSize.ISize(mWritingMode)
: mSize.BSize(mWritingMode);
}
nsSize PhysicalSize() const { return mSize.GetPhysicalSize(mWritingMode); }
// It's only meaningful to consider "ascent" on the block-start side of the
// frame, so no need to pass a writing mode argument
enum { ASK_FOR_BASELINE = nscoord_MAX };
nscoord BlockStartAscent() const { return mBlockStartAscent; }
void SetBlockStartAscent(nscoord aAscent) { mBlockStartAscent = aAscent; }
// Metrics that _exactly_ enclose the text to allow precise MathML placements.
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}.
OverflowAreas mOverflowAreas;
nsRect& InkOverflow() { return mOverflowAreas.InkOverflow(); }
const nsRect& InkOverflow() const { return mOverflowAreas.InkOverflow(); }
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:
// Desired size of a frame's border-box.
LogicalSize mSize;
// Baseline (in block direction), or the default value ASK_FOR_BASELINE.
nscoord mBlockStartAscent = ASK_FOR_BASELINE;
mozilla::WritingMode mWritingMode;
};
} // namespace mozilla
#endif // mozilla_ReflowOutput_h