diff -r 000000000000 -r 6474c204b198 layout/generic/nsHTMLReflowState.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/layout/generic/nsHTMLReflowState.h Wed Dec 31 06:09:35 2014 +0100 @@ -0,0 +1,716 @@ +/* -*- 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 input to nsIFrame::Reflow */ + +#ifndef nsHTMLReflowState_h___ +#define nsHTMLReflowState_h___ + +#include "nsMargin.h" +#include "nsStyleCoord.h" +#include "nsIFrame.h" +#include "mozilla/Assertions.h" +#include + +class nsPresContext; +class nsRenderingContext; +class nsFloatManager; +class nsLineLayout; +class nsIPercentHeightObserver; +struct nsHypotheticalBox; + +/** + * @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 +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; +} + +/** + * CSS Frame type. Included as part of the reflow state. + */ +typedef uint32_t nsCSSFrameType; + +#define NS_CSS_FRAME_TYPE_UNKNOWN 0 +#define NS_CSS_FRAME_TYPE_INLINE 1 +#define NS_CSS_FRAME_TYPE_BLOCK 2 /* block-level in normal flow */ +#define NS_CSS_FRAME_TYPE_FLOATING 3 +#define NS_CSS_FRAME_TYPE_ABSOLUTE 4 +#define NS_CSS_FRAME_TYPE_INTERNAL_TABLE 5 /* row group frame, row frame, cell frame, ... */ + +/** + * Bit-flag that indicates whether the element is replaced. Applies to inline, + * block-level, floating, and absolutely positioned elements + */ +#define NS_CSS_FRAME_TYPE_REPLACED 0x08000 + +/** + * Bit-flag that indicates that the element is replaced and contains a block + * (eg some form controls). Applies to inline, block-level, floating, and + * absolutely positioned elements. Mutually exclusive with + * NS_CSS_FRAME_TYPE_REPLACED. + */ +#define NS_CSS_FRAME_TYPE_REPLACED_CONTAINS_BLOCK 0x10000 + +/** + * Helper macros for telling whether items are replaced + */ +#define NS_FRAME_IS_REPLACED_NOBLOCK(_ft) \ + (NS_CSS_FRAME_TYPE_REPLACED == ((_ft) & NS_CSS_FRAME_TYPE_REPLACED)) + +#define NS_FRAME_IS_REPLACED(_ft) \ + (NS_FRAME_IS_REPLACED_NOBLOCK(_ft) || \ + NS_FRAME_IS_REPLACED_CONTAINS_BLOCK(_ft)) + +#define NS_FRAME_REPLACED(_ft) \ + (NS_CSS_FRAME_TYPE_REPLACED | (_ft)) + +#define NS_FRAME_IS_REPLACED_CONTAINS_BLOCK(_ft) \ + (NS_CSS_FRAME_TYPE_REPLACED_CONTAINS_BLOCK == \ + ((_ft) & NS_CSS_FRAME_TYPE_REPLACED_CONTAINS_BLOCK)) + +#define NS_FRAME_REPLACED_CONTAINS_BLOCK(_ft) \ + (NS_CSS_FRAME_TYPE_REPLACED_CONTAINS_BLOCK | (_ft)) + +/** + * A macro to extract the type. Masks off the 'replaced' bit-flag + */ +#define NS_FRAME_GET_TYPE(_ft) \ + ((_ft) & ~(NS_CSS_FRAME_TYPE_REPLACED | \ + NS_CSS_FRAME_TYPE_REPLACED_CONTAINS_BLOCK)) + +// A base class of nsHTMLReflowState that computes only the padding, +// border, and margin, since those values are needed more often. +struct nsCSSOffsetState { +public: + typedef mozilla::WritingMode WritingMode; + typedef mozilla::LogicalMargin LogicalMargin; + + // the frame being reflowed + nsIFrame* frame; + + // rendering context to use for measurement + nsRenderingContext* rendContext; + + const nsMargin& ComputedPhysicalMargin() const { return mComputedMargin; } + const nsMargin& ComputedPhysicalBorderPadding() const { return mComputedBorderPadding; } + const nsMargin& ComputedPhysicalPadding() const { return mComputedPadding; } + + // We may need to eliminate the (few) users of these writable-reference accessors + // as part of migrating to logical coordinates. + nsMargin& ComputedPhysicalMargin() { return mComputedMargin; } + nsMargin& ComputedPhysicalBorderPadding() { return mComputedBorderPadding; } + nsMargin& ComputedPhysicalPadding() { return mComputedPadding; } + + LogicalMargin ComputedLogicalMargin() const + { return LogicalMargin(mWritingMode, mComputedMargin); } + LogicalMargin ComputedLogicalBorderPadding() const + { return LogicalMargin(mWritingMode, mComputedBorderPadding); } + LogicalMargin ComputedLogicalPadding() const + { return LogicalMargin(mWritingMode, mComputedPadding); } + + WritingMode GetWritingMode() const { return mWritingMode; } + +protected: + // cached copy of the frame's writing-mode, for logical coordinates + WritingMode mWritingMode; + + // These are PHYSICAL coordinates (for now). + // Will probably become logical in due course. + + // Computed margin values + nsMargin mComputedMargin; + + // Cached copy of the border + padding values + nsMargin mComputedBorderPadding; + + // Computed padding values + nsMargin mComputedPadding; + +public: + // Callers using this constructor must call InitOffsets on their own. + nsCSSOffsetState(nsIFrame *aFrame, nsRenderingContext *aRenderingContext) + : frame(aFrame) + , rendContext(aRenderingContext) + , mWritingMode(aFrame->GetWritingMode()) + { + } + + nsCSSOffsetState(nsIFrame *aFrame, nsRenderingContext *aRenderingContext, + nscoord aContainingBlockWidth); + +#ifdef DEBUG + // Reflow trace methods. Defined in nsFrame.cpp so they have access + // to the display-reflow infrastructure. + static void* DisplayInitOffsetsEnter(nsIFrame* aFrame, + nsCSSOffsetState* aState, + nscoord aHorizontalPercentBasis, + nscoord aVerticalPercentBasis, + const nsMargin* aBorder, + const nsMargin* aPadding); + static void DisplayInitOffsetsExit(nsIFrame* aFrame, + nsCSSOffsetState* aState, + void* aValue); +#endif + +private: + /** + * Computes margin values from the specified margin style information, and + * fills in the mComputedMargin member. + * + * @param aHorizontalPercentBasis + * Length to use for resolving percentage margin values in the horizontal + * axis. Usually the containing block width. + * @param aVerticalPercentBasis + * Length to use for resolving percentage margin values in the vertical + * axis. Usually the containing block width, per CSS21 sec 8.3, but may + * be the containing block *height*, e.g. in CSS3 Flexbox and Grid. + * @return true if the margin is dependent on the containing block size. + */ + bool ComputeMargin(nscoord aHorizontalPercentBasis, + nscoord aVerticalPercentBasis); + + /** + * Computes padding values from the specified padding style information, and + * fills in the mComputedPadding member. + * + * @param aHorizontalPercentBasis + * Length to use for resolving percentage padding values in the horizontal + * axis. Usually the containing block width. + * @param aVerticalPercentBasis + * Length to use for resolving percentage padding values in the vertical + * axis. Usually the containing block width, per CSS21 sec 8.4, but may + * be the containing block *height* in e.g. CSS3 Flexbox and Grid. + * @return true if the padding is dependent on the containing block size. + */ + bool ComputePadding(nscoord aHorizontalPercentBasis, + nscoord aVerticalPercentBasis, nsIAtom* aFrameType); + +protected: + + void InitOffsets(nscoord aHorizontalPercentBasis, + nscoord aVerticalPercentBasis, + nsIAtom* aFrameType, + const nsMargin *aBorder = nullptr, + const nsMargin *aPadding = nullptr); + + /* + * Convert nsStyleCoord to nscoord when percentages depend on the + * containing block width, and enumerated values are for width, + * min-width, or max-width. Does not handle auto widths. + */ + inline nscoord ComputeWidthValue(nscoord aContainingBlockWidth, + nscoord aContentEdgeToBoxSizing, + nscoord aBoxSizingToMarginEdge, + const nsStyleCoord& aCoord); + // same as previous, but using mComputedBorderPadding, mComputedPadding, + // and mComputedMargin + nscoord ComputeWidthValue(nscoord aContainingBlockWidth, + uint8_t aBoxSizing, + const nsStyleCoord& aCoord); + + nscoord ComputeHeightValue(nscoord aContainingBlockHeight, + uint8_t aBoxSizing, + const nsStyleCoord& aCoord); +}; + +/** + * 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 nsHTMLReflowState : public nsCSSOffsetState { + // the reflow states are linked together. this is the pointer to the + // parent's reflow state + const nsHTMLReflowState* parentReflowState; + + // pointer to the float manager associated with this area + nsFloatManager* mFloatManager; + + // LineLayout object (only for inline reflow; set to nullptr otherwise) + nsLineLayout* mLineLayout; + + // The appropriate reflow state for the containing block (for + // percentage widths, etc.) of this reflow state's frame. + const nsHTMLReflowState *mCBReflowState; + + // The type of frame, from css's perspective. This value is + // initialized by the Init method below. + nsCSSFrameType mFrameType; + + // 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; + + // Accessors for the private fields below. Forcing all callers to use these + // will allow us to introduce logical-coordinate versions and gradually + // change clients from physical to logical as needed; and potentially switch + // the internal fields from physical to logical coordinates in due course, + // while maintaining compatibility with not-yet-updated code. + nscoord AvailableWidth() const { return mAvailableWidth; } + nscoord AvailableHeight() const { return mAvailableHeight; } + nscoord ComputedWidth() const { return mComputedWidth; } + nscoord ComputedHeight() const { return mComputedHeight; } + nscoord ComputedMinWidth() const { return mComputedMinWidth; } + nscoord ComputedMaxWidth() const { return mComputedMaxWidth; } + nscoord ComputedMinHeight() const { return mComputedMinHeight; } + nscoord ComputedMaxHeight() const { return mComputedMaxHeight; } + + nscoord& AvailableWidth() { return mAvailableWidth; } + nscoord& AvailableHeight() { return mAvailableHeight; } + nscoord& ComputedWidth() { return mComputedWidth; } + nscoord& ComputedHeight() { return mComputedHeight; } + nscoord& ComputedMinWidth() { return mComputedMinWidth; } + nscoord& ComputedMaxWidth() { return mComputedMaxWidth; } + nscoord& ComputedMinHeight() { return mComputedMinHeight; } + nscoord& ComputedMaxHeight() { return mComputedMaxHeight; } + + // 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 AvailableISize() const + { return mWritingMode.IsVertical() ? mAvailableHeight : mAvailableWidth; } + nscoord AvailableBSize() const + { return mWritingMode.IsVertical() ? mAvailableWidth : mAvailableHeight; } + nscoord ComputedISize() const + { return mWritingMode.IsVertical() ? mComputedHeight : mComputedWidth; } + nscoord ComputedBSize() const + { return mWritingMode.IsVertical() ? mComputedWidth : mComputedHeight; } + nscoord ComputedMinISize() const + { return mWritingMode.IsVertical() ? mComputedMinHeight : mComputedMinWidth; } + nscoord ComputedMaxISize() const + { return mWritingMode.IsVertical() ? mComputedMaxHeight : mComputedMaxWidth; } + nscoord ComputedMinBSize() const + { return mWritingMode.IsVertical() ? mComputedMinWidth : mComputedMinHeight; } + nscoord ComputedMaxBSize() const + { return mWritingMode.IsVertical() ? mComputedMaxWidth : mComputedMaxHeight; } + + nscoord& AvailableISize() + { return mWritingMode.IsVertical() ? mAvailableHeight : mAvailableWidth; } + nscoord& AvailableBSize() + { return mWritingMode.IsVertical() ? mAvailableWidth : mAvailableHeight; } + nscoord& ComputedISize() + { return mWritingMode.IsVertical() ? mComputedHeight : mComputedWidth; } + nscoord& ComputedBSize() + { return mWritingMode.IsVertical() ? mComputedWidth : mComputedHeight; } + nscoord& ComputedMinISize() + { return mWritingMode.IsVertical() ? mComputedMinHeight : mComputedMinWidth; } + nscoord& ComputedMaxISize() + { return mWritingMode.IsVertical() ? mComputedMaxHeight : mComputedMaxWidth; } + nscoord& ComputedMinBSize() + { return mWritingMode.IsVertical() ? mComputedMinWidth : mComputedMinHeight; } + nscoord& ComputedMaxBSize() + { return mWritingMode.IsVertical() ? mComputedMaxWidth : mComputedMaxHeight; } + + // XXX this will need to change when we make mComputedOffsets logical; + // we won't be able to return a reference for the physical offsets + const nsMargin& ComputedPhysicalOffsets() const { return mComputedOffsets; } + nsMargin& ComputedPhysicalOffsets() { return mComputedOffsets; } + + LogicalMargin ComputedLogicalOffsets() const + { return LogicalMargin(mWritingMode, mComputedOffsets); } + +private: + // the available width in which to reflow the frame. The space + // represents the amount of room for the frame's margin, border, + // padding, and content area. The frame size you choose should fit + // within the available width. + nscoord mAvailableWidth; + + // A value of NS_UNCONSTRAINEDSIZE for the available height means + // you can choose whatever size you want. In galley mode the + // available height is always NS_UNCONSTRAINEDSIZE, and only page + // mode or multi-column layout involves a constrained height. The + // element's the top border and padding, and content, must fit. If the + // element is complete after reflow then its bottom border, padding + // and margin (and similar for its complete ancestors) will need to + // fit in this height. + nscoord mAvailableHeight; + + // The computed width specifies the frame's content area width, and it does + // not apply to inline non-replaced elements + // + // For replaced inline frames, a value of NS_INTRINSICSIZE means you should + // use your intrinsic width as the computed width + // + // For block-level frames, the computed width is based on the width of the + // containing block, the margin/border/padding areas, and the min/max width. + nscoord mComputedWidth; + + // The computed height specifies the frame's content height, and it does + // not apply to inline non-replaced elements + // + // For replaced inline frames, a value of NS_INTRINSICSIZE means you should + // use your intrinsic height as the computed height + // + // For non-replaced block-level frames in the flow and floated, a value of + // NS_AUTOHEIGHT means you choose a height to shrink wrap around the normal + // flow child frames. The height must be within the limit of the min/max + // height if there is such a limit + // + // For replaced block-level frames, a value of NS_INTRINSICSIZE + // means you use your intrinsic height as the computed height + nscoord mComputedHeight; + + // Computed values for 'left/top/right/bottom' offsets. Only applies to + // 'positioned' elements. These are PHYSICAL coordinates (for now). + nsMargin mComputedOffsets; + + // Computed values for 'min-width/max-width' and 'min-height/max-height' + // XXXldb The width ones here should go; they should be needed only + // internally. + nscoord mComputedMinWidth, mComputedMaxWidth; + nscoord mComputedMinHeight, mComputedMaxHeight; + +public: + // Cached pointers to the various style structs used during intialization + const nsStyleDisplay* mStyleDisplay; + const nsStyleVisibility* mStyleVisibility; + const nsStylePosition* mStylePosition; + const nsStyleBorder* mStyleBorder; + const nsStyleMargin* mStyleMargin; + const nsStylePadding* mStylePadding; + const nsStyleText* mStyleText; + + bool IsFloating() const; + + uint8_t GetDisplay() const; + + // a frame (e.g. nsTableCellFrame) which may need to generate a special + // reflow for percent height calculations + nsIPercentHeightObserver* mPercentHeightObserver; + + // 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; + + // This value keeps track of how deeply nested a given reflow state + // is from the top of the frame tree. + int16_t mReflowDepth; + + struct ReflowStateFlags { + uint16_t mSpecialHeightReflow:1; // used by tables to communicate special reflow (in process) to handle + // percent height frames inside cells which may not have computed heights + uint16_t mNextInFlowUntouched:1; // nothing in the frame's next-in-flow (or its descendants) + // is changing + uint16_t mIsTopOfPage: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. + uint16_t mHasClearance:1; // Block has clearance + uint16_t mAssumingHScrollbar:1; // parent frame is an nsIScrollableFrame and it + // is assuming a horizontal scrollbar + uint16_t mAssumingVScrollbar:1; // parent frame is an nsIScrollableFrame and it + // is assuming a vertical scrollbar + + uint16_t mHResize:1; // Is frame (a) not dirty and (b) a + // different width than before? + + uint16_t mVResize:1; // Is frame (a) not dirty and (b) a + // different height than before or + // (potentially) in a context where + // percent heights have a different + // basis? + uint16_t mTableIsSplittable:1; // tables are splittable, this should happen only inside a page + // and never insider a column frame + uint16_t mHeightDependsOnAncestorCell:1; // Does frame height depend on + // an ancestor table-cell? + uint16_t mIsColumnBalancing:1; // nsColumnSetFrame is balancing columns + uint16_t mIsFlexContainerMeasuringHeight:1; // nsFlexContainerFrame is + // reflowing this child to + // measure its intrinsic height. + uint16_t mDummyParentReflowState:1; // a "fake" reflow state made + // in order to be the parent + // of a real one + uint16_t mMustReflowPlaceholders: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. + } mFlags; + + // 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 state. + * + * @param aPresContext Must be equal to aFrame->PresContext(). + * @param aFrame The frame for whose reflow state is being constructed. + * @param aRenderingContext The rendering context to be used for measurements. + * @param aAvailableSpace See comments for availableHeight and availableWidth + * members. + * @param aFlags A set of flags used for additional boolean parameters (see + * below). + */ + nsHTMLReflowState(nsPresContext* aPresContext, + nsIFrame* aFrame, + nsRenderingContext* aRenderingContext, + const nsSize& aAvailableSpace, + uint32_t aFlags = 0); + + /** + * Initialize a reflow state for a child frame's reflow. Some parts of the + * state are copied from the parent's reflow state. The remainder is computed. + * + * @param aPresContext Must be equal to aFrame->PresContext(). + * @param aParentReflowState A reference to an nsHTMLReflowState object that + * is to be the parent of this object. + * @param aFrame The frame for whose reflow state is being constructed. + * @param aAvailableSpace See comments for availableHeight and availableWidth + * members. + * @param aContainingBlockWidth An optional width, in app units, that is used + * by absolute positioning code to override default containing block + * width. + * @param aContainingBlockHeight An optional height, in app units, that is + * used by absolute positioning code to override default containing + * block height. + * @param aFlags A set of flags used for additional boolean parameters (see + * below). + */ + nsHTMLReflowState(nsPresContext* aPresContext, + const nsHTMLReflowState& aParentReflowState, + nsIFrame* aFrame, + const nsSize& aAvailableSpace, + nscoord aContainingBlockWidth = -1, + nscoord aContainingBlockHeight = -1, + uint32_t aFlags = 0); + + // Values for |aFlags| passed to constructor + enum { + // Indicates that the parent of this reflow state is "fake" (see + // mDummyParentReflowState in mFlags). + DUMMY_PARENT_REFLOW_STATE = (1<<0), + + // Indicates that the calling function will initialize the reflow state, and + // that the constructor should not call Init(). + CALLER_WILL_INIT = (1<<1) + }; + + // This method initializes various data members. It is automatically + // called by the various constructors + void Init(nsPresContext* aPresContext, + nscoord aContainingBlockWidth = -1, + nscoord aContainingBlockHeight = -1, + const nsMargin* aBorder = nullptr, + const nsMargin* aPadding = nullptr); + /** + * Find the content width of the containing block of aReflowState + */ + static nscoord + GetContainingBlockContentWidth(const nsHTMLReflowState* aReflowState); + + /** + * 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 state. + * + * @param aBlockHeight The computed height of the content rect of the block + * that the line should fill. + * Only used with line-height:-moz-block-height. + * NS_AUTOHEIGHT 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, + nsStyleContext* aStyleContext, + nscoord aBlockHeight, + float aFontSizeInflation); + + + void ComputeContainingBlockRectangle(nsPresContext* aPresContext, + const nsHTMLReflowState* aContainingBlockRS, + nscoord& aContainingBlockWidth, + nscoord& aContainingBlockHeight); + + /** + * 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)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; + } + + bool ShouldReflowAllKids() const { + // Note that we could make a stronger optimization for mVResize if + // we use it in a ShouldReflowChild test that replaces the current + // checks of NS_FRAME_IS_DIRTY | NS_FRAME_HAS_DIRTY_CHILDREN, if it + // were tested there along with NS_FRAME_CONTAINS_RELATIVE_HEIGHT. + // This would need to be combined with a slight change in which + // frames NS_FRAME_CONTAINS_RELATIVE_HEIGHT is marked on. + return (frame->GetStateBits() & NS_FRAME_IS_DIRTY) || + mFlags.mHResize || + (mFlags.mVResize && + (frame->GetStateBits() & NS_FRAME_CONTAINS_RELATIVE_HEIGHT)); + } + + // This method doesn't apply min/max computed widths to the value passed in. + void SetComputedWidth(nscoord aComputedWidth); + + // This method doesn't apply min/max computed heights to the value passed in. + void SetComputedHeight(nscoord aComputedHeight); + + void SetComputedHeightWithoutResettingResizeFlags(nscoord aComputedHeight) { + // Viewport frames reset the computed height on a copy of their reflow + // state 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 width is pointless. + ComputedHeight() = aComputedHeight; + } + + void SetTruncated(const nsHTMLReflowMetrics& aMetrics, nsReflowStatus* aStatus) const; + + bool WillReflowAgainForClearance() const { + return mDiscoveredClearance && *mDiscoveredClearance; + } + + // Compute the offsets for a relative position element + static void ComputeRelativeOffsets(uint8_t aCBDirection, + nsIFrame* aFrame, + nscoord aContainingBlockWidth, + nscoord aContainingBlockHeight, + nsMargin& aComputedOffsets); + + // 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(frame, ComputedPhysicalOffsets(), aPosition); + } + +#ifdef DEBUG + // Reflow trace methods. Defined in nsFrame.cpp so they have access + // to the display-reflow infrastructure. + static void* DisplayInitConstraintsEnter(nsIFrame* aFrame, + nsHTMLReflowState* aState, + nscoord aCBWidth, + nscoord aCBHeight, + const nsMargin* aBorder, + const nsMargin* aPadding); + static void DisplayInitConstraintsExit(nsIFrame* aFrame, + nsHTMLReflowState* aState, + void* aValue); + static void* DisplayInitFrameTypeEnter(nsIFrame* aFrame, + nsHTMLReflowState* aState); + static void DisplayInitFrameTypeExit(nsIFrame* aFrame, + nsHTMLReflowState* aState, + void* aValue); +#endif + +protected: + void InitFrameType(nsIAtom* aFrameType); + void InitCBReflowState(); + void InitResizeFlags(nsPresContext* aPresContext, nsIAtom* aFrameType); + + void InitConstraints(nsPresContext* aPresContext, + nscoord aContainingBlockWidth, + nscoord aContainingBlockHeight, + const nsMargin* aBorder, + const nsMargin* aPadding, + nsIAtom* aFrameType); + + // Returns the nearest containing block or block frame (whether or not + // it is a containing block) for the specified frame. Also returns + // the left edge and width of the containing block's content area. + // These are returned in the coordinate space of the containing block. + nsIFrame* GetHypotheticalBoxContainer(nsIFrame* aFrame, + nscoord& aCBLeftEdge, + nscoord& aCBWidth); + + void CalculateHypotheticalBox(nsPresContext* aPresContext, + nsIFrame* aPlaceholderFrame, + nsIFrame* aContainingBlock, + nscoord aBlockLeftContentEdge, + nscoord aBlockContentWidth, + const nsHTMLReflowState* cbrs, + nsHypotheticalBox& aHypotheticalBox, + nsIAtom* aFrameType); + + void InitAbsoluteConstraints(nsPresContext* aPresContext, + const nsHTMLReflowState* cbrs, + nscoord aContainingBlockWidth, + nscoord aContainingBlockHeight, + nsIAtom* aFrameType); + + // Calculates the computed values for the 'min-Width', 'max-Width', + // 'min-Height', and 'max-Height' properties, and stores them in the assorted + // data members + void ComputeMinMaxValues(nscoord aContainingBlockWidth, + nscoord aContainingBlockHeight, + const nsHTMLReflowState* aContainingBlockRS); + + void CalculateHorizBorderPaddingMargin(nscoord aContainingBlockWidth, + nscoord* aInsideBoxSizing, + nscoord* aOutsideBoxSizing); + + void CalculateBlockSideMargins(nscoord aAvailWidth, + nscoord aComputedWidth, + nsIAtom* aFrameType); +}; + +#endif /* nsHTMLReflowState_h___ */ +