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Diffstat (limited to 'layout/generic/ReflowInput.h')
| -rw-r--r-- | layout/generic/ReflowInput.h | 953 |
1 files changed, 953 insertions, 0 deletions
diff --git a/layout/generic/ReflowInput.h b/layout/generic/ReflowInput.h new file mode 100644 index 0000000000..e0f286710a --- /dev/null +++ b/layout/generic/ReflowInput.h @@ -0,0 +1,953 @@ +/* -*- 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/. */ + +/* struct containing the input to nsIFrame::Reflow */ + +#ifndef mozilla_ReflowInput_h +#define mozilla_ReflowInput_h + +#include "nsMargin.h" +#include "nsStyleConsts.h" +#include "mozilla/Assertions.h" +#include "mozilla/EnumSet.h" +#include "mozilla/Maybe.h" +#include "mozilla/WritingModes.h" +#include "LayoutConstants.h" +#include "ReflowOutput.h" +#include <algorithm> + +class gfxContext; +class nsFloatManager; +struct nsHypotheticalPosition; +class nsIPercentBSizeObserver; +class nsLineLayout; +class nsPlaceholderFrame; +class nsPresContext; +class nsReflowStatus; + +namespace mozilla { +enum class LayoutFrameType : uint8_t; +} + +/** + * @return aValue clamped to [aMinValue, aMaxValue]. + * + * @note This function needs to handle aMinValue > aMaxValue. In that case, + * aMinValue is returned. + * @see http://www.w3.org/TR/CSS21/visudet.html#min-max-widths + * @see http://www.w3.org/TR/CSS21/visudet.html#min-max-heights + */ +template <class NumericType> +NumericType NS_CSS_MINMAX(NumericType aValue, NumericType aMinValue, + NumericType aMaxValue) { + NumericType result = aValue; + if (aMaxValue < result) result = aMaxValue; + if (aMinValue > result) result = aMinValue; + return result; +} + +namespace mozilla { + +// A base class of ReflowInput that computes only the padding, +// border, and margin, since those values are needed more often. +struct SizeComputationInput { + public: + // The frame being reflowed. + nsIFrame* mFrame; + + // Rendering context to use for measurement. + gfxContext* mRenderingContext; + + nsMargin ComputedPhysicalMargin() const { + return mComputedMargin.GetPhysicalMargin(mWritingMode); + } + nsMargin ComputedPhysicalBorderPadding() const { + return mComputedBorderPadding.GetPhysicalMargin(mWritingMode); + } + nsMargin ComputedPhysicalPadding() const { + return mComputedPadding.GetPhysicalMargin(mWritingMode); + } + + mozilla::LogicalMargin ComputedLogicalMargin(mozilla::WritingMode aWM) const { + return mComputedMargin.ConvertTo(aWM, mWritingMode); + } + mozilla::LogicalMargin ComputedLogicalBorderPadding( + mozilla::WritingMode aWM) const { + return mComputedBorderPadding.ConvertTo(aWM, mWritingMode); + } + mozilla::LogicalMargin ComputedLogicalPadding( + mozilla::WritingMode aWM) const { + return mComputedPadding.ConvertTo(aWM, mWritingMode); + } + + void SetComputedLogicalMargin(mozilla::WritingMode aWM, + const mozilla::LogicalMargin& aMargin) { + mComputedMargin = aMargin.ConvertTo(mWritingMode, aWM); + } + void SetComputedLogicalBorderPadding( + mozilla::WritingMode aWM, const mozilla::LogicalMargin& aBorderPadding) { + mComputedBorderPadding = aBorderPadding.ConvertTo(mWritingMode, aWM); + } + void SetComputedLogicalPadding(mozilla::WritingMode aWM, + const mozilla::LogicalMargin& aPadding) { + mComputedPadding = aPadding.ConvertTo(mWritingMode, aWM); + } + + mozilla::WritingMode GetWritingMode() const { return mWritingMode; } + + protected: + // cached copy of the frame's writing-mode, for logical coordinates + mozilla::WritingMode mWritingMode; + + // Computed margin values + mozilla::LogicalMargin mComputedMargin; + + // Cached copy of the border + padding values + mozilla::LogicalMargin mComputedBorderPadding; + + // Computed padding values + mozilla::LogicalMargin mComputedPadding; + + public: + // Callers using this constructor must call InitOffsets on their own. + SizeComputationInput(nsIFrame* aFrame, gfxContext* aRenderingContext); + + SizeComputationInput(nsIFrame* aFrame, gfxContext* aRenderingContext, + mozilla::WritingMode aContainingBlockWritingMode, + nscoord aContainingBlockISize); + +#ifdef DEBUG + // Reflow trace methods. Defined in nsFrame.cpp so they have access + // to the display-reflow infrastructure. + static void* DisplayInitOffsetsEnter(nsIFrame* aFrame, + SizeComputationInput* aState, + nscoord aPercentBasis, + mozilla::WritingMode aCBWritingMode, + const nsMargin* aBorder, + const nsMargin* aPadding); + static void DisplayInitOffsetsExit(nsIFrame* aFrame, + SizeComputationInput* aState, + void* aValue); +#endif + + private: + /** + * Computes margin values from the specified margin style information, and + * fills in the mComputedMargin member. + * + * @param aCBWM Writing mode of the containing block + * @param aPercentBasis + * Inline size of the containing block (in its own writing mode), to use + * for resolving percentage margin values in the inline and block axes. + * @return true if the margin is dependent on the containing block size. + */ + bool ComputeMargin(mozilla::WritingMode aCBWM, nscoord aPercentBasis); + + /** + * Computes padding values from the specified padding style information, and + * fills in the mComputedPadding member. + * + * @param aCBWM Writing mode of the containing block + * @param aPercentBasis + * Inline size of the containing block (in its own writing mode), to use + * for resolving percentage padding values in the inline and block axes. + * @return true if the padding is dependent on the containing block size. + */ + bool ComputePadding(mozilla::WritingMode aCBWM, nscoord aPercentBasis, + mozilla::LayoutFrameType aFrameType); + + protected: + void InitOffsets(mozilla::WritingMode aCBWM, nscoord aPercentBasis, + mozilla::LayoutFrameType aFrameType, + mozilla::ComputeSizeFlags aFlags = {}, + const mozilla::Maybe<mozilla::LogicalMargin>& aBorder = + mozilla::Nothing(), + const mozilla::Maybe<mozilla::LogicalMargin>& aPadding = + mozilla::Nothing(), + const nsStyleDisplay* aDisplay = nullptr); + + /* + * Convert StyleSize or StyleMaxSize to nscoord when percentages depend on the + * inline size of the containing block, and enumerated values are for inline + * size, min-inline-size, or max-inline-size. Does not handle auto inline + * sizes. + */ + template <typename SizeOrMaxSize> + inline nscoord ComputeISizeValue(const WritingMode aWM, + const LogicalSize& aContainingBlockSize, + const LogicalSize& aContentEdgeToBoxSizing, + nscoord aBoxSizingToMarginEdge, + const SizeOrMaxSize&) const; + // same as previous, but using mComputedBorderPadding, mComputedPadding, + // and mComputedMargin + template <typename SizeOrMaxSize> + inline nscoord ComputeISizeValue(const LogicalSize& aContainingBlockSize, + mozilla::StyleBoxSizing aBoxSizing, + const SizeOrMaxSize&) const; + + nscoord ComputeBSizeValue(nscoord aContainingBlockBSize, + mozilla::StyleBoxSizing aBoxSizing, + const mozilla::LengthPercentage& aCoord) const; +}; + +/** + * State passed to a frame during reflow or intrinsic size calculation. + * + * XXX Refactor so only a base class (nsSizingState?) is used for intrinsic + * size calculation. + * + * @see nsIFrame#Reflow() + */ +struct ReflowInput : public SizeComputationInput { + // the reflow inputs are linked together. this is the pointer to the + // parent's reflow input + const ReflowInput* mParentReflowInput = nullptr; + + // A non-owning pointer to the float manager associated with this area, + // which points to the object owned by nsAutoFloatManager::mNew. + nsFloatManager* mFloatManager = nullptr; + + // LineLayout object (only for inline reflow; set to nullptr otherwise) + nsLineLayout* mLineLayout = nullptr; + + // The appropriate reflow input for the containing block (for + // percentage widths, etc.) of this reflow input's frame. It will be setup + // properly in InitCBReflowInput(). + const ReflowInput* mCBReflowInput = nullptr; + + // The amount the in-flow position of the block is moving vertically relative + // to its previous in-flow position (i.e. the amount the line containing the + // block is moving). + // This should be zero for anything which is not a block outside, and it + // should be zero for anything which has a non-block parent. + // The intended use of this value is to allow the accurate determination + // of the potential impact of a float + // This takes on an arbitrary value the first time a block is reflowed + nscoord mBlockDelta = 0; + + // If a ReflowInput finds itself initialized with an unconstrained + // inline-size, it will look up its parentReflowInput chain for a reflow input + // with an orthogonal writing mode and a non-NS_UNCONSTRAINEDSIZE value for + // orthogonal limit; when it finds such a reflow input, it will use its + // orthogonal-limit value to constrain inline-size. + // This is initialized to NS_UNCONSTRAINEDSIZE (so it will be ignored), + // but reset to a suitable value for the reflow root by PresShell. + nscoord mOrthogonalLimit = NS_UNCONSTRAINEDSIZE; + + // Physical accessors for the private fields. They are needed for + // compatibility with not-yet-updated code. New code should use the accessors + // for logical coordinates, unless the code really works on physical + // coordinates. + nscoord AvailableWidth() const { return mAvailableSize.Width(mWritingMode); } + nscoord AvailableHeight() const { + return mAvailableSize.Height(mWritingMode); + } + nscoord ComputedWidth() const { return mComputedSize.Width(mWritingMode); } + nscoord ComputedHeight() const { return mComputedSize.Height(mWritingMode); } + nscoord ComputedMinWidth() const { + return mComputedMinSize.Width(mWritingMode); + } + nscoord ComputedMaxWidth() const { + return mComputedMaxSize.Width(mWritingMode); + } + nscoord ComputedMinHeight() const { + return mComputedMinSize.Height(mWritingMode); + } + nscoord ComputedMaxHeight() const { + return mComputedMaxSize.Height(mWritingMode); + } + + // Logical accessors for private fields in mWritingMode. + nscoord AvailableISize() const { return mAvailableSize.ISize(mWritingMode); } + nscoord AvailableBSize() const { return mAvailableSize.BSize(mWritingMode); } + nscoord ComputedISize() const { return mComputedSize.ISize(mWritingMode); } + nscoord ComputedBSize() const { return mComputedSize.BSize(mWritingMode); } + nscoord ComputedMinISize() const { + return mComputedMinSize.ISize(mWritingMode); + } + nscoord ComputedMaxISize() const { + return mComputedMaxSize.ISize(mWritingMode); + } + nscoord ComputedMinBSize() const { + return mComputedMinSize.BSize(mWritingMode); + } + nscoord ComputedMaxBSize() const { + return mComputedMaxSize.BSize(mWritingMode); + } + + nscoord& AvailableISize() { return mAvailableSize.ISize(mWritingMode); } + nscoord& AvailableBSize() { return mAvailableSize.BSize(mWritingMode); } + nscoord& ComputedISize() { return mComputedSize.ISize(mWritingMode); } + nscoord& ComputedBSize() { return mComputedSize.BSize(mWritingMode); } + nscoord& ComputedMinISize() { return mComputedMinSize.ISize(mWritingMode); } + nscoord& ComputedMaxISize() { return mComputedMaxSize.ISize(mWritingMode); } + nscoord& ComputedMinBSize() { return mComputedMinSize.BSize(mWritingMode); } + nscoord& ComputedMaxBSize() { return mComputedMaxSize.BSize(mWritingMode); } + + mozilla::LogicalSize AvailableSize() const { return mAvailableSize; } + mozilla::LogicalSize ComputedSize() const { return mComputedSize; } + mozilla::LogicalSize ComputedMinSize() const { return mComputedMinSize; } + mozilla::LogicalSize ComputedMaxSize() const { return mComputedMaxSize; } + + mozilla::LogicalSize AvailableSize(mozilla::WritingMode aWM) const { + return AvailableSize().ConvertTo(aWM, mWritingMode); + } + mozilla::LogicalSize ComputedSize(mozilla::WritingMode aWM) const { + return ComputedSize().ConvertTo(aWM, mWritingMode); + } + mozilla::LogicalSize ComputedMinSize(mozilla::WritingMode aWM) const { + return ComputedMinSize().ConvertTo(aWM, mWritingMode); + } + mozilla::LogicalSize ComputedMaxSize(mozilla::WritingMode aWM) const { + return ComputedMaxSize().ConvertTo(aWM, mWritingMode); + } + + mozilla::LogicalSize ComputedSizeWithPadding(mozilla::WritingMode aWM) const { + return ComputedSize(aWM) + ComputedLogicalPadding(aWM).Size(aWM); + } + + mozilla::LogicalSize ComputedSizeWithBorderPadding( + mozilla::WritingMode aWM) const { + return ComputedSize(aWM) + ComputedLogicalBorderPadding(aWM).Size(aWM); + } + + mozilla::LogicalSize ComputedSizeWithMarginBorderPadding( + mozilla::WritingMode aWM) const { + return ComputedSizeWithBorderPadding(aWM) + + ComputedLogicalMargin(aWM).Size(aWM); + } + + nsSize ComputedPhysicalSize() const { + return nsSize(ComputedWidth(), ComputedHeight()); + } + + nsMargin ComputedPhysicalOffsets() const { + return mComputedOffsets.GetPhysicalMargin(mWritingMode); + } + + LogicalMargin ComputedLogicalOffsets(mozilla::WritingMode aWM) const { + return mComputedOffsets.ConvertTo(aWM, mWritingMode); + } + + void SetComputedLogicalOffsets(mozilla::WritingMode aWM, + const LogicalMargin& aOffsets) { + mComputedOffsets = aOffsets.ConvertTo(mWritingMode, aWM); + } + + // Return ReflowInput's computed size including border-padding, with + // unconstrained dimensions replaced by zero. + nsSize ComputedSizeAsContainerIfConstrained() const { + const nscoord wd = ComputedWidth(); + const nscoord ht = ComputedHeight(); + return nsSize(wd == NS_UNCONSTRAINEDSIZE + ? 0 + : wd + ComputedPhysicalBorderPadding().LeftRight(), + ht == NS_UNCONSTRAINEDSIZE + ? 0 + : ht + ComputedPhysicalBorderPadding().TopBottom()); + } + + // Our saved containing block dimensions. + LogicalSize mContainingBlockSize{mWritingMode}; + + // Cached pointers to the various style structs used during initialization. + const nsStyleDisplay* mStyleDisplay = nullptr; + const nsStyleVisibility* mStyleVisibility = nullptr; + const nsStylePosition* mStylePosition = nullptr; + const nsStyleBorder* mStyleBorder = nullptr; + const nsStyleMargin* mStyleMargin = nullptr; + const nsStylePadding* mStylePadding = nullptr; + const nsStyleText* mStyleText = nullptr; + + bool IsFloating() const; + + // a frame (e.g. nsTableCellFrame) which may need to generate a special + // reflow for percent bsize calculations + nsIPercentBSizeObserver* mPercentBSizeObserver = nullptr; + + // CSS margin collapsing sometimes requires us to reflow + // optimistically assuming that margins collapse to see if clearance + // is required. When we discover that clearance is required, we + // store the frame in which clearance was discovered to the location + // requested here. + nsIFrame** mDiscoveredClearance = nullptr; + + struct Flags { + Flags() { memset(this, 0, sizeof(*this)); } + + // cached mFrame->IsFrameOfType(nsIFrame::eReplaced) || + // mFrame->IsFrameOfType(nsIFrame::eReplacedContainsBlock) + bool mIsReplaced : 1; + + // used by tables to communicate special reflow (in process) to handle + // percent bsize frames inside cells which may not have computed bsizes + bool mSpecialBSizeReflow : 1; + + // nothing in the frame's next-in-flow (or its descendants) is changing + bool mNextInFlowUntouched : 1; + + // Is the current context at the top of a page? When true, we force + // something that's too tall for a page/column to fit anyway to avoid + // infinite loops. + bool mIsTopOfPage : 1; + + // parent frame is an nsIScrollableFrame and it is assuming a horizontal + // scrollbar + bool mAssumingHScrollbar : 1; + + // parent frame is an nsIScrollableFrame and it is assuming a vertical + // scrollbar + bool mAssumingVScrollbar : 1; + + // Is frame a different inline-size than before? + bool mIsIResize : 1; + + // Is frame (potentially) a different block-size than before? + // This includes cases where the block-size is 'auto' and the + // contents or width have changed. + bool mIsBResize : 1; + + // Has this frame changed block-size in a way that affects + // block-size percentages on frames for which it is the containing + // block? This includes a change between 'auto' and a length that + // doesn't actually change the frame's block-size. It does not + // include cases where the block-size is 'auto' and the frame's + // contents have changed. + // + // In the current code, this is only true when mIsBResize is also + // true, although it doesn't necessarily need to be that way (e.g., + // in the case of a frame changing from 'auto' to a length that + // produces the same height). + bool mIsBResizeForPercentages : 1; + + // tables are splittable, this should happen only inside a page and never + // insider a column frame + bool mTableIsSplittable : 1; + + // Does frame height depend on an ancestor table-cell? + bool mHeightDependsOnAncestorCell : 1; + + // nsColumnSetFrame is balancing columns + bool mIsColumnBalancing : 1; + + // True if ColumnSetWrapperFrame has a constrained block-size, and is going + // to consume all of its block-size in this fragment. This bit is passed to + // nsColumnSetFrame to determine whether to give up balancing and create + // overflow columns. + bool mColumnSetWrapperHasNoBSizeLeft : 1; + + // nsFlexContainerFrame is reflowing this child to measure its intrinsic + // BSize. + bool mIsFlexContainerMeasuringBSize : 1; + + // If this flag is set, the BSize of this frame should be considered + // indefinite for the purposes of percent resolution on child frames (we + // should behave as if ComputedBSize() were NS_UNCONSTRAINEDSIZE when doing + // percent resolution against this.ComputedBSize()). For example: flex + // items may have their ComputedBSize() resolved ahead-of-time by their + // flex container, and yet their BSize might have to be considered + // indefinite per https://drafts.csswg.org/css-flexbox/#definite-sizes + bool mTreatBSizeAsIndefinite : 1; + + // a "fake" reflow input made in order to be the parent of a real one + bool mDummyParentReflowInput : 1; + + // Should this frame reflow its place-holder children? If the available + // height of this frame didn't change, but its in a paginated environment + // (e.g. columns), it should always reflow its placeholder children. + bool mMustReflowPlaceholders : 1; + + // the STATIC_POS_IS_CB_ORIGIN ctor flag + bool mStaticPosIsCBOrigin : 1; + + // If set, the following two flags indicate that: + // (1) this frame is absolutely-positioned (or fixed-positioned). + // (2) this frame's static position depends on the CSS Box Alignment. + // (3) we do need to compute the static position, because the frame's + // {Inline and/or Block} offsets actually depend on it. + // When these bits are set, the offset values (IStart/IEnd, BStart/BEnd) + // represent the "start" edge of the frame's CSS Box Alignment container + // area, in that axis -- and these offsets need to be further-resolved + // (with CSS Box Alignment) after we know the OOF frame's size. + // NOTE: The "I" and "B" (for "Inline" and "Block") refer the axes of the + // *containing block's writing-mode*, NOT mFrame's own writing-mode. This + // is purely for convenience, since that's the writing-mode we're dealing + // with when we set & react to these bits. + bool mIOffsetsNeedCSSAlign : 1; + bool mBOffsetsNeedCSSAlign : 1; + + // Are we somewhere inside an element with -webkit-line-clamp set? + // This flag is inherited into descendant ReflowInputs, but we don't bother + // resetting it to false when crossing over into a block descendant that + // -webkit-line-clamp skips over (such as a BFC). + bool mInsideLineClamp : 1; + + // Is this a flex item, and should we add or remove a -webkit-line-clamp + // ellipsis on a descendant line? It's possible for this flag to be true + // when mInsideLineClamp is false if we previously had a numeric + // -webkit-line-clamp value, but now have 'none' and we need to find the + // line with the ellipsis flag and clear it. + // This flag is not inherited into descendant ReflowInputs. + bool mApplyLineClamp : 1; + + // Is this frame or one of its ancestors being reflowed in a different + // continuation than the one in which it was previously reflowed? In + // other words, has it moved to a different column or page than it was in + // the previous reflow? + // + // FIXME: For now, we only ensure that this is set correctly for blocks. + // This is okay because the only thing that uses it only cares about + // whether there's been a fragment change within the same block formatting + // context. + bool mMovedBlockFragments : 1; + + // Is the block-size computed by aspect-ratio and inline size (i.e. block + // axis is the ratio-dependent axis)? We set this flag so that we can check + // whether to apply automatic content-based minimum sizes once we know the + // children's block-size (after reflowing them). + // https://drafts.csswg.org/css-sizing-4/#aspect-ratio-minimum + bool mIsBSizeSetByAspectRatio : 1; + }; + Flags mFlags; + mozilla::ComputeSizeFlags mComputeSizeFlags; + + // This value keeps track of how deeply nested a given reflow input + // is from the top of the frame tree. + int16_t mReflowDepth = 0; + + // Logical and physical accessors for the resize flags. + bool IsHResize() const { + return mWritingMode.IsVertical() ? mFlags.mIsBResize : mFlags.mIsIResize; + } + bool IsVResize() const { + return mWritingMode.IsVertical() ? mFlags.mIsIResize : mFlags.mIsBResize; + } + bool IsIResize() const { return mFlags.mIsIResize; } + bool IsBResize() const { return mFlags.mIsBResize; } + bool IsBResizeForWM(mozilla::WritingMode aWM) const { + return aWM.IsOrthogonalTo(mWritingMode) ? mFlags.mIsIResize + : mFlags.mIsBResize; + } + bool IsBResizeForPercentagesForWM(mozilla::WritingMode aWM) const { + // This uses the relatively-accurate mIsBResizeForPercentages flag + // when the writing modes are parallel, and is a bit more + // pessimistic when orthogonal. + return !aWM.IsOrthogonalTo(mWritingMode) ? mFlags.mIsBResizeForPercentages + : IsIResize(); + } + void SetHResize(bool aValue) { + if (mWritingMode.IsVertical()) { + mFlags.mIsBResize = aValue; + } else { + mFlags.mIsIResize = aValue; + } + } + void SetVResize(bool aValue) { + if (mWritingMode.IsVertical()) { + mFlags.mIsIResize = aValue; + } else { + mFlags.mIsBResize = aValue; + } + } + void SetIResize(bool aValue) { mFlags.mIsIResize = aValue; } + void SetBResize(bool aValue) { mFlags.mIsBResize = aValue; } + + // Values for |aFlags| passed to constructor + enum class InitFlag : uint8_t { + // Indicates that the parent of this reflow input is "fake" (see + // mDummyParentReflowInput in mFlags). + DummyParentReflowInput, + + // Indicates that the calling function will initialize the reflow input, and + // that the constructor should not call Init(). + CallerWillInit, + + // The caller wants the abs.pos. static-position resolved at the origin of + // the containing block, i.e. at LogicalPoint(0, 0). (Note that this + // doesn't necessarily mean that (0, 0) is the *correct* static position + // for the frame in question.) + // @note In a Grid container's masonry axis we'll always use + // the placeholder's position in that axis regardless of this flag. + StaticPosIsCBOrigin, + }; + using InitFlags = mozilla::EnumSet<InitFlag>; + + // Note: The copy constructor is written by the compiler automatically. You + // can use that and then override specific values if you want, or you can + // call Init as desired... + + /** + * Initialize a ROOT reflow input. + * + * @param aPresContext Must be equal to aFrame->PresContext(). + * @param aFrame The frame for whose reflow input is being constructed. + * @param aRenderingContext The rendering context to be used for measurements. + * @param aAvailableSpace The available space to reflow aFrame (in aFrame's + * writing-mode). See comments for mAvailableSize for more information. + * @param aFlags A set of flags used for additional boolean parameters (see + * InitFlags above). + */ + ReflowInput(nsPresContext* aPresContext, nsIFrame* aFrame, + gfxContext* aRenderingContext, + const mozilla::LogicalSize& aAvailableSpace, + InitFlags aFlags = {}); + + /** + * Initialize a reflow input for a child frame's reflow. Some parts of the + * state are copied from the parent's reflow input. The remainder is computed. + * + * @param aPresContext Must be equal to aFrame->PresContext(). + * @param aParentReflowInput A reference to an ReflowInput object that + * is to be the parent of this object. + * @param aFrame The frame for whose reflow input is being constructed. + * @param aAvailableSpace The available space to reflow aFrame (in aFrame's + * writing-mode). See comments for mAvailableSize for more information. + * @param aContainingBlockSize An optional size (in aFrame's writing mode), + * specifying the containing block size to use instead of the default + * size computed by ComputeContainingBlockRectangle(). If + * InitFlag::CallerWillInit is used, this is ignored. Pass it via + * Init() instead. + * @param aFlags A set of flags used for additional boolean parameters (see + * InitFlags above). + * @param aComputeSizeFlags A set of flags used when we call + * nsIFrame::ComputeSize() internally. + */ + ReflowInput(nsPresContext* aPresContext, + const ReflowInput& aParentReflowInput, nsIFrame* aFrame, + const mozilla::LogicalSize& aAvailableSpace, + const mozilla::Maybe<mozilla::LogicalSize>& aContainingBlockSize = + mozilla::Nothing(), + InitFlags aFlags = {}, + mozilla::ComputeSizeFlags aComputeSizeFlags = {}); + + /** + * This method initializes various data members. It is automatically called by + * the constructors if InitFlags::CallerWillInit is *not* used. + * + * @param aContainingBlockSize An optional size (in mFrame's writing mode), + * specifying the containing block size to use instead of the default + * size computed by ComputeContainingBlockRectangle(). + * @param aBorder An optional border (in mFrame's writing mode). If given, use + * it instead of the border computed from mFrame's StyleBorder. + * @param aPadding An optional padding (in mFrame's writing mode). If given, + * use it instead of the padding computing from mFrame's StylePadding. + */ + void Init(nsPresContext* aPresContext, + const mozilla::Maybe<mozilla::LogicalSize>& aContainingBlockSize = + mozilla::Nothing(), + const mozilla::Maybe<mozilla::LogicalMargin>& aBorder = + mozilla::Nothing(), + const mozilla::Maybe<mozilla::LogicalMargin>& aPadding = + mozilla::Nothing()); + + /** + * Find the content isize of our containing block for the given writing mode, + * which need not be the same as the reflow input's mode. + */ + nscoord GetContainingBlockContentISize( + mozilla::WritingMode aWritingMode) const; + + /** + * Calculate the used line-height property. The return value will be >= 0. + */ + nscoord CalcLineHeight() const; + + /** + * Same as CalcLineHeight() above, but doesn't need a reflow input. + * + * @param aBlockBSize The computed block size of the content rect of the block + * that the line should fill. + * Only used with line-height:-moz-block-height. + * NS_UNCONSTRAINEDSIZE results in a normal line-height + * for line-height:-moz-block-height. + * @param aFontSizeInflation The result of the appropriate + * nsLayoutUtils::FontSizeInflationFor call, + * or 1.0 if during intrinsic size + * calculation. + */ + static nscoord CalcLineHeight(nsIContent* aContent, + ComputedStyle* aComputedStyle, + nsPresContext* aPresContext, + nscoord aBlockBSize, float aFontSizeInflation); + + mozilla::LogicalSize ComputeContainingBlockRectangle( + nsPresContext* aPresContext, const ReflowInput* aContainingBlockRI) const; + + /** + * Apply the mComputed(Min/Max)Width constraints to the content + * size computed so far. + */ + nscoord ApplyMinMaxWidth(nscoord aWidth) const { + if (NS_UNCONSTRAINEDSIZE != ComputedMaxWidth()) { + aWidth = std::min(aWidth, ComputedMaxWidth()); + } + return std::max(aWidth, ComputedMinWidth()); + } + + /** + * Apply the mComputed(Min/Max)ISize constraints to the content + * size computed so far. + */ + nscoord ApplyMinMaxISize(nscoord aISize) const { + if (NS_UNCONSTRAINEDSIZE != ComputedMaxISize()) { + aISize = std::min(aISize, ComputedMaxISize()); + } + return std::max(aISize, ComputedMinISize()); + } + + /** + * Apply the mComputed(Min/Max)Height constraints to the content + * size computed so far. + * + * @param aHeight The height that we've computed an to which we want to apply + * min/max constraints. + * @param aConsumed The amount of the computed height that was consumed by + * our prev-in-flows. + */ + nscoord ApplyMinMaxHeight(nscoord aHeight, nscoord aConsumed = 0) const { + aHeight += aConsumed; + + if (NS_UNCONSTRAINEDSIZE != ComputedMaxHeight()) { + aHeight = std::min(aHeight, ComputedMaxHeight()); + } + + if (NS_UNCONSTRAINEDSIZE != ComputedMinHeight()) { + aHeight = std::max(aHeight, ComputedMinHeight()); + } + + return aHeight - aConsumed; + } + + /** + * Apply the mComputed(Min/Max)BSize constraints to the content + * size computed so far. + * + * @param aBSize The block-size that we've computed an to which we want to + * apply min/max constraints. + * @param aConsumed The amount of the computed block-size that was consumed by + * our prev-in-flows. + */ + nscoord ApplyMinMaxBSize(nscoord aBSize, nscoord aConsumed = 0) const { + aBSize += aConsumed; + + if (NS_UNCONSTRAINEDSIZE != ComputedMaxBSize()) { + aBSize = std::min(aBSize, ComputedMaxBSize()); + } + + if (NS_UNCONSTRAINEDSIZE != ComputedMinBSize()) { + aBSize = std::max(aBSize, ComputedMinBSize()); + } + + return aBSize - aConsumed; + } + + bool ShouldReflowAllKids() const; + + // This method doesn't apply min/max computed widths to the value passed in. + void SetComputedWidth(nscoord aComputedWidth) { + if (mWritingMode.IsVertical()) { + SetComputedBSize(aComputedWidth); + } else { + SetComputedISize(aComputedWidth); + } + } + + // This method doesn't apply min/max computed heights to the value passed in. + void SetComputedHeight(nscoord aComputedHeight) { + if (mWritingMode.IsVertical()) { + SetComputedISize(aComputedHeight); + } else { + SetComputedBSize(aComputedHeight); + } + } + + // This method doesn't apply min/max computed inline-sizes to the value passed + // in. + void SetComputedISize(nscoord aComputedISize); + + // These methods don't apply min/max computed block-sizes to the value passed + // in. + void SetComputedBSize(nscoord aComputedBSize); + void SetComputedBSizeWithoutResettingResizeFlags(nscoord aComputedBSize) { + // Viewport frames reset the computed block size on a copy of their reflow + // input when reflowing fixed-pos kids. In that case we actually don't + // want to mess with the resize flags, because comparing the frame's rect + // to the munged computed isize is pointless. + MOZ_ASSERT(aComputedBSize >= 0, "Invalid computed block-size!"); + ComputedBSize() = aComputedBSize; + } + + void SetTruncated(const ReflowOutput& aMetrics, + nsReflowStatus* aStatus) const; + + bool WillReflowAgainForClearance() const { + return mDiscoveredClearance && *mDiscoveredClearance; + } + + // Compute the offsets for a relative position element + // + // @param aWM the writing mode of aCBSize and the returned offsets. + static mozilla::LogicalMargin ComputeRelativeOffsets( + mozilla::WritingMode aWM, nsIFrame* aFrame, + const mozilla::LogicalSize& aCBSize); + + // If a relatively positioned element, adjust the position appropriately. + static void ApplyRelativePositioning(nsIFrame* aFrame, + const nsMargin& aComputedOffsets, + nsPoint* aPosition); + + void ApplyRelativePositioning(nsPoint* aPosition) const { + ApplyRelativePositioning(mFrame, ComputedPhysicalOffsets(), aPosition); + } + + static void ApplyRelativePositioning( + nsIFrame* aFrame, mozilla::WritingMode aWritingMode, + const mozilla::LogicalMargin& aComputedOffsets, + mozilla::LogicalPoint* aPosition, const nsSize& aContainerSize); + + void ApplyRelativePositioning(mozilla::LogicalPoint* aPosition, + const nsSize& aContainerSize) const { + ApplyRelativePositioning(mFrame, mWritingMode, + ComputedLogicalOffsets(mWritingMode), aPosition, + aContainerSize); + } + +#ifdef DEBUG + // Reflow trace methods. Defined in nsFrame.cpp so they have access + // to the display-reflow infrastructure. + static void* DisplayInitConstraintsEnter(nsIFrame* aFrame, + ReflowInput* aState, + nscoord aCBISize, nscoord aCBBSize, + const nsMargin* aBorder, + const nsMargin* aPadding); + static void DisplayInitConstraintsExit(nsIFrame* aFrame, ReflowInput* aState, + void* aValue); + static void* DisplayInitFrameTypeEnter(nsIFrame* aFrame, ReflowInput* aState); + static void DisplayInitFrameTypeExit(nsIFrame* aFrame, ReflowInput* aState, + void* aValue); +#endif + + protected: + void InitCBReflowInput(); + void InitResizeFlags(nsPresContext* aPresContext, + mozilla::LayoutFrameType aFrameType); + void InitDynamicReflowRoot(); + + void InitConstraints( + nsPresContext* aPresContext, + const mozilla::Maybe<mozilla::LogicalSize>& aContainingBlockSize, + const mozilla::Maybe<mozilla::LogicalMargin>& aBorder, + const mozilla::Maybe<mozilla::LogicalMargin>& aPadding, + mozilla::LayoutFrameType aFrameType); + + // Returns the nearest containing block or block frame (whether or not + // it is a containing block) for the specified frame. Also returns + // the inline-start edge and logical size of the containing block's + // content area. + // These are returned in the coordinate space of the containing block. + nsIFrame* GetHypotheticalBoxContainer(nsIFrame* aFrame, + nscoord& aCBIStartEdge, + mozilla::LogicalSize& aCBSize) const; + + // Calculate a "hypothetical box" position where the placeholder frame + // (for a position:fixed/absolute element) would have been placed if it were + // positioned statically. The hypothetical box position will have a writing + // mode with the same block direction as the absolute containing block + // (aCBReflowInput->frame), though it may differ in inline direction. + void CalculateHypotheticalPosition(nsPresContext* aPresContext, + nsPlaceholderFrame* aPlaceholderFrame, + const ReflowInput* aCBReflowInput, + nsHypotheticalPosition& aHypotheticalPos, + mozilla::LayoutFrameType aFrameType) const; + + // Check if we can use the resolved auto block size (by insets) to compute + // the inline size through aspect-ratio on absolute-positioned elements. + // This is only needed for non-replaced elements. + // https://drafts.csswg.org/css-position/#abspos-auto-size + bool IsInlineSizeComputableByBlockSizeAndAspectRatio( + nscoord aBlockSize) const; + + // This calculates the size by using the resolved auto block size (from + // non-auto block insets), according to the writing mode of current block. + LogicalSize CalculateAbsoluteSizeWithResolvedAutoBlockSize( + nscoord aAutoBSize, bool aNeedsComputeInlineSizeByAspectRatio, + const LogicalSize& aTentativeComputedSize); + + void InitAbsoluteConstraints(nsPresContext* aPresContext, + const ReflowInput* aCBReflowInput, + const mozilla::LogicalSize& aContainingBlockSize, + mozilla::LayoutFrameType aFrameType); + + // Calculates the computed values for the 'min-inline-size', + // 'max-inline-size', 'min-block-size', and 'max-block-size' properties, and + // stores them in the assorted data members + void ComputeMinMaxValues(const mozilla::LogicalSize& aCBSize); + + // aInsideBoxSizing returns the part of the padding, border, and margin + // in the aAxis dimension that goes inside the edge given by box-sizing; + // aOutsideBoxSizing returns the rest. + void CalculateBorderPaddingMargin(mozilla::LogicalAxis aAxis, + nscoord aContainingBlockSize, + nscoord* aInsideBoxSizing, + nscoord* aOutsideBoxSizing) const; + + void CalculateBlockSideMargins(LayoutFrameType aFrameType); + + /** + * @return true if mFrame is an internal table frame, i.e. an + * ns[RowGroup|ColGroup|Row|Cell]Frame. (We exclude nsTableColFrame + * here since we never setup a ReflowInput for those.) + */ + bool IsInternalTableFrame() const; + + private: + // The available size in which to reflow the frame. The space represents the + // amount of room for the frame's margin, border, padding, and content area. + // + // The available inline-size should be constrained. The frame's inline-size + // you choose should fit within it. + + // In galley mode, the available block-size is always unconstrained, and only + // page mode or multi-column layout involves a constrained available + // block-size. + // + // An unconstrained available block-size means you can choose whatever size + // you want. If the value is constrained, the frame's block-start border, + // padding, and content, must fit. If a frame is fully-complete after reflow, + // then its block-end border, padding, and margin (and similar for its + // fully-complete ancestors) will need to fit within this available + // block-size. However, if a frame is monolithic, it may choose a block-size + // larger than the available block-size. + mozilla::LogicalSize mAvailableSize{mWritingMode}; + + // The computed size specifies the frame's content area, and it does not apply + // to inline non-replaced elements. + // + // For block-level frames, the computed inline-size is based on the + // inline-size of the containing block, the margin/border/padding areas, and + // the min/max inline-size. + // + // For non-replaced block-level frames in the flow and floated, if the + // computed block-size is NS_UNCONSTRAINEDSIZE, you should choose a block-size + // to shrink wrap around the normal flow child frames. The block-size must be + // within the limit of the min/max block-size if there is such a limit. + mozilla::LogicalSize mComputedSize{mWritingMode}; + + // Computed values for 'inset' properties. Only applies to 'positioned' + // elements. + mozilla::LogicalMargin mComputedOffsets{mWritingMode}; + + // Computed value for 'min-inline-size'/'min-block-size'. + mozilla::LogicalSize mComputedMinSize{mWritingMode}; + + // Computed value for 'max-inline-size'/'max-block-size'. + mozilla::LogicalSize mComputedMaxSize{mWritingMode, NS_UNCONSTRAINEDSIZE, + NS_UNCONSTRAINEDSIZE}; +}; + +} // namespace mozilla + +#endif // mozilla_ReflowInput_h |