Mozilla/mozilla/layout/generic/nsHTMLReflowState.cpp
bzbarsky%mit.edu ba5badedcb Change the FrameNeedsReflow API to pass the dirty flags to be added directly to
the method, instead of setting them before calling the method.  That way we can
avoid reflowing the ancestor of a reflow root which is not itself dirty but has
dirty children.  This also makes it harder to set dirty bits inconsistently
with the FrameNeedsReflow call.  Bug 378784, r+sr=dbaron, pending rbs' review
on the mathml parts.


git-svn-id: svn://10.0.0.236/trunk@226007 18797224-902f-48f8-a5cc-f745e15eee43
2007-05-06 19:16:52 +00:00

2197 lines
86 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Communicator client code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/* struct containing the input to nsIFrame::Reflow */
#include "nsCOMPtr.h"
#include "nsStyleConsts.h"
#include "nsCSSAnonBoxes.h"
#include "nsFrame.h"
#include "nsIContent.h"
#include "nsGkAtoms.h"
#include "nsPresContext.h"
#include "nsIPresShell.h"
#include "nsIDeviceContext.h"
#include "nsIRenderingContext.h"
#include "nsIFontMetrics.h"
#include "nsBlockFrame.h"
#include "nsLineBox.h"
#include "nsImageFrame.h"
#include "nsTableFrame.h"
#include "nsIServiceManager.h"
#include "nsIPercentHeightObserver.h"
#include "nsContentUtils.h"
#include "nsLayoutUtils.h"
#ifdef IBMBIDI
#include "nsBidiUtils.h"
#endif
#ifdef NS_DEBUG
#undef NOISY_VERTICAL_ALIGN
#else
#undef NOISY_VERTICAL_ALIGN
#endif
// Prefs-driven control for |text-decoration: blink|
static PRPackedBool sPrefIsLoaded = PR_FALSE;
static PRPackedBool sBlinkIsAllowed = PR_TRUE;
enum eNormalLineHeightControl {
eUninitialized = -1,
eNoExternalLeading = 0, // does not include external leading
eIncludeExternalLeading, // use whatever value font vendor provides
eCompensateLeading // compensate leading if leading provided by font vendor is not enough
};
#ifdef FONT_LEADING_APIS_V2
static eNormalLineHeightControl sNormalLineHeightControl = eUninitialized;
#endif
// Initialize a <b>root</b> reflow state with a rendering context to
// use for measuring things.
nsHTMLReflowState::nsHTMLReflowState(nsPresContext* aPresContext,
nsIFrame* aFrame,
nsIRenderingContext* aRenderingContext,
const nsSize& aAvailableSpace)
: nsCSSOffsetState(aFrame, aRenderingContext)
, mReflowDepth(0)
{
NS_PRECONDITION(aPresContext, "no pres context");
NS_PRECONDITION(aRenderingContext, "no rendering context");
NS_PRECONDITION(aFrame, "no frame");
parentReflowState = nsnull;
availableWidth = aAvailableSpace.width;
availableHeight = aAvailableSpace.height;
mSpaceManager = nsnull;
mLineLayout = nsnull;
mFlags.mSpecialHeightReflow = PR_FALSE;
mFlags.mIsTopOfPage = PR_FALSE;
mFlags.mTableIsSplittable = PR_FALSE;
mFlags.mNextInFlowUntouched = PR_FALSE;
mFlags.mAssumingHScrollbar = mFlags.mAssumingVScrollbar = PR_FALSE;
mFlags.mHasClearance = PR_FALSE;
mDiscoveredClearance = nsnull;
mPercentHeightObserver = nsnull;
mPercentHeightReflowInitiator = nsnull;
Init(aPresContext);
#ifdef IBMBIDI
mRightEdge = NS_UNCONSTRAINEDSIZE;
#endif
}
static PRBool CheckNextInFlowParenthood(nsIFrame* aFrame, nsIFrame* aParent)
{
nsIFrame* frameNext = aFrame->GetNextInFlow();
nsIFrame* parentNext = aParent->GetNextInFlow();
return frameNext && parentNext && frameNext->GetParent() == parentNext;
}
// Initialize a reflow state for a child frames reflow. Some state
// is copied from the parent reflow state; the remaining state is
// computed.
nsHTMLReflowState::nsHTMLReflowState(nsPresContext* aPresContext,
const nsHTMLReflowState& aParentReflowState,
nsIFrame* aFrame,
const nsSize& aAvailableSpace,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight,
PRBool aInit)
: nsCSSOffsetState(aFrame, aParentReflowState.rendContext)
, mReflowDepth(aParentReflowState.mReflowDepth + 1)
, mFlags(aParentReflowState.mFlags)
{
NS_PRECONDITION(aPresContext, "no pres context");
NS_PRECONDITION(aFrame, "no frame");
NS_PRECONDITION((aContainingBlockWidth == -1) ==
(aContainingBlockHeight == -1),
"cb width and height should only be non-default together");
NS_PRECONDITION(aInit == PR_TRUE || aInit == PR_FALSE,
"aInit out of range for PRBool");
NS_PRECONDITION(!mFlags.mSpecialHeightReflow ||
!NS_SUBTREE_DIRTY(aFrame),
"frame should be clean when getting special height reflow");
parentReflowState = &aParentReflowState;
// If the parent is dirty, then the child is as well.
// XXX Are the other cases where the parent reflows a child a second
// time, as a resize?
if (!mFlags.mSpecialHeightReflow)
frame->AddStateBits(parentReflowState->frame->GetStateBits() &
NS_FRAME_IS_DIRTY);
availableWidth = aAvailableSpace.width;
availableHeight = aAvailableSpace.height;
mSpaceManager = aParentReflowState.mSpaceManager;
mLineLayout = aParentReflowState.mLineLayout;
mFlags.mIsTopOfPage = aParentReflowState.mFlags.mIsTopOfPage;
mFlags.mNextInFlowUntouched = aParentReflowState.mFlags.mNextInFlowUntouched &&
CheckNextInFlowParenthood(aFrame, aParentReflowState.frame);
mFlags.mAssumingHScrollbar = mFlags.mAssumingVScrollbar = PR_FALSE;
mFlags.mHasClearance = PR_FALSE;
mDiscoveredClearance = nsnull;
mPercentHeightObserver = (aParentReflowState.mPercentHeightObserver &&
aParentReflowState.mPercentHeightObserver->NeedsToObserve(*this))
? aParentReflowState.mPercentHeightObserver : nsnull;
mPercentHeightReflowInitiator = aParentReflowState.mPercentHeightReflowInitiator;
if (aInit) {
Init(aPresContext, aContainingBlockWidth, aContainingBlockHeight);
}
#ifdef IBMBIDI
mRightEdge = aParentReflowState.mRightEdge;
#endif // IBMBIDI
}
inline void
nsCSSOffsetState::ComputeWidthDependentValue(nscoord aContainingBlockWidth,
const nsStyleCoord& aCoord,
nscoord& aResult)
{
aResult = nsLayoutUtils::ComputeWidthDependentValue(rendContext, frame,
aContainingBlockWidth,
aCoord);
}
inline nscoord
nsCSSOffsetState::ComputeWidthValue(nscoord aContainingBlockWidth,
nscoord aContentEdgeToBoxSizing,
nscoord aBoxSizingToMarginEdge,
const nsStyleCoord& aCoord)
{
return nsLayoutUtils::ComputeWidthValue(rendContext, frame,
aContainingBlockWidth,
aContentEdgeToBoxSizing,
aBoxSizingToMarginEdge,
aCoord);
}
nscoord
nsCSSOffsetState::ComputeWidthValue(nscoord aContainingBlockWidth,
PRUint8 aBoxSizing,
const nsStyleCoord& aCoord)
{
nscoord inside = 0, outside = mComputedBorderPadding.LeftRight() +
mComputedMargin.LeftRight();
switch (aBoxSizing) {
case NS_STYLE_BOX_SIZING_BORDER:
inside = mComputedBorderPadding.LeftRight();
break;
case NS_STYLE_BOX_SIZING_PADDING:
inside = mComputedPadding.LeftRight();
break;
}
outside -= inside;
return ComputeWidthValue(aContainingBlockWidth, inside,
outside, aCoord);
}
inline void
nsCSSOffsetState::ComputeHeightDependentValue(nscoord aContainingBlockHeight,
const nsStyleCoord& aCoord,
nscoord& aResult)
{
aResult = nsLayoutUtils::ComputeHeightDependentValue(rendContext, frame,
aContainingBlockHeight,
aCoord);
}
void
nsHTMLReflowState::SetComputedWidth(nscoord aComputedWidth)
{
NS_ASSERTION(frame, "Must have a frame!");
// It'd be nice to assert that |frame| is not in reflow, but this fails for
// two reasons:
//
// 1) Viewport frames reset the computed width 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.
// 2) nsFrame::BoxReflow creates a reflow state for its parent. This reflow
// state is not used to reflow the parent, but just as a parent for the
// frame's own reflow state. So given a nsBoxFrame inside some non-XUL
// (like a text control, for example), we'll end up creating a reflow
// state for the parent while the parent is reflowing.
NS_PRECONDITION(aComputedWidth >= 0, "Invalid computed width");
if (mComputedWidth != aComputedWidth) {
mComputedWidth = aComputedWidth;
if (frame->GetType() != nsGkAtoms::viewportFrame) { // Or check GetParent()?
InitResizeFlags(frame->PresContext());
}
}
}
void
nsHTMLReflowState::Init(nsPresContext* aPresContext,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight,
const nsMargin* aBorder,
const nsMargin* aPadding)
{
NS_ASSERTION(availableWidth != NS_UNCONSTRAINEDSIZE,
"shouldn't use unconstrained widths anymore");
mStylePosition = frame->GetStylePosition();
mStyleDisplay = frame->GetStyleDisplay();
mStyleVisibility = frame->GetStyleVisibility();
mStyleBorder = frame->GetStyleBorder();
mStyleMargin = frame->GetStyleMargin();
mStylePadding = frame->GetStylePadding();
mStyleText = frame->GetStyleText();
InitFrameType();
InitCBReflowState();
InitConstraints(aPresContext, aContainingBlockWidth, aContainingBlockHeight, aBorder, aPadding);
InitResizeFlags(aPresContext);
NS_ASSERTION((mFrameType == NS_CSS_FRAME_TYPE_INLINE &&
!frame->IsFrameOfType(nsIFrame::eReplaced)) ||
frame->GetType() == nsGkAtoms::textFrame ||
mComputedWidth != NS_UNCONSTRAINEDSIZE,
"shouldn't use unconstrained widths anymore");
}
void nsHTMLReflowState::InitCBReflowState()
{
if (!parentReflowState) {
mCBReflowState = nsnull;
return;
}
if (parentReflowState->frame->IsContainingBlock() ||
// Absolutely positioned frames should always be kids of the frames that
// determine their containing block
(NS_FRAME_GET_TYPE(mFrameType) == NS_CSS_FRAME_TYPE_ABSOLUTE)) {
// a block inside a table cell needs to use the table cell
if (parentReflowState->parentReflowState &&
IS_TABLE_CELL(parentReflowState->parentReflowState->frame->GetType())) {
mCBReflowState = parentReflowState->parentReflowState;
} else {
mCBReflowState = parentReflowState;
}
return;
}
mCBReflowState = parentReflowState->mCBReflowState;
}
void
nsHTMLReflowState::InitResizeFlags(nsPresContext* aPresContext)
{
mFlags.mHResize = !(frame->GetStateBits() & NS_FRAME_IS_DIRTY) &&
frame->GetSize().width !=
mComputedWidth + mComputedBorderPadding.LeftRight();
// XXX Should we really need to null check mCBReflowState? (We do for
// at least nsBoxFrame).
if (mFlags.mSpecialHeightReflow && IS_TABLE_CELL(frame->GetType()) &&
(frame->GetStateBits() & NS_FRAME_CONTAINS_RELATIVE_HEIGHT)) {
mFlags.mVResize = PR_TRUE;
} else if (mCBReflowState && !frame->IsContainingBlock()) {
// XXX Is this problematic for relatively positioned inlines acting
// as containing block for absolutely positioned elements?
mFlags.mVResize = mCBReflowState->mFlags.mVResize;
} else if (mComputedHeight == NS_AUTOHEIGHT) {
if (eCompatibility_NavQuirks == aPresContext->CompatibilityMode() &&
mCBReflowState) {
// XXX This condition doesn't quite match CalcQuirkContainingBlockHeight.
mFlags.mVResize = mCBReflowState->mFlags.mVResize;
} else {
mFlags.mVResize = mFlags.mHResize || NS_SUBTREE_DIRTY(frame);
}
} else {
// not 'auto' height
mFlags.mVResize = frame->GetSize().height !=
mComputedHeight + mComputedBorderPadding.TopBottom();
}
// It would be nice to check that |mComputedHeight != NS_AUTOHEIGHT|
// &&ed with the percentage height check. However, this doesn't get
// along with table special height reflows, since a special height
// reflow (a quirk that makes such percentage heights work on children
// of table cells) can cause not just a single percentage height to
// become fixed, but an entire descendant chain of percentage heights
// to become fixed.
if ((mStylePosition->mHeight.GetUnit() == eStyleUnit_Percent ||
mStylePosition->mMinHeight.GetUnit() == eStyleUnit_Percent ||
mStylePosition->mMaxHeight.GetUnit() == eStyleUnit_Percent ||
mStylePosition->mOffset.GetTopUnit() == eStyleUnit_Percent ||
mStylePosition->mOffset.GetBottomUnit() == eStyleUnit_Percent ||
frame->IsBoxFrame()) &&
mCBReflowState) {
const nsHTMLReflowState *rs = this;
do {
rs = rs->parentReflowState;
if (rs->frame->GetStateBits() & NS_FRAME_CONTAINS_RELATIVE_HEIGHT)
break; // no need to go further
rs->frame->AddStateBits(NS_FRAME_CONTAINS_RELATIVE_HEIGHT);
} while (rs != mCBReflowState);
}
if (frame->GetStateBits() & NS_FRAME_IS_DIRTY) {
// If we're reflowing everything, then we'll find out if we need
// to re-set this.
frame->RemoveStateBits(NS_FRAME_CONTAINS_RELATIVE_HEIGHT);
}
}
/* static */
nscoord
nsHTMLReflowState::GetContainingBlockContentWidth(const nsHTMLReflowState* aReflowState)
{
const nsHTMLReflowState* rs = aReflowState->mCBReflowState;
if (!rs)
return 0;
return rs->mComputedWidth;
}
/* static */
nsIFrame*
nsHTMLReflowState::GetContainingBlockFor(const nsIFrame* aFrame)
{
NS_PRECONDITION(aFrame, "Must have frame to work with");
nsIFrame* container = aFrame->GetParent();
if (aFrame->GetStyleDisplay()->IsAbsolutelyPositioned()) {
// Absolutely positioned frames are just kids of their containing
// blocks (which may happen to be inlines).
return container;
}
while (container && !container->IsContainingBlock()) {
container = container->GetParent();
}
return container;
}
void
nsHTMLReflowState::InitFrameType()
{
const nsStyleDisplay *disp = mStyleDisplay;
nsCSSFrameType frameType;
// Section 9.7 of the CSS2 spec indicates that absolute position
// takes precedence over float which takes precedence over display.
// Make sure the frame was actually moved out of the flow, and don't
// just assume what the style says
// XXXldb nsRuleNode::ComputeDisplayData should take care of this, right?
if (frame->GetStateBits() & NS_FRAME_OUT_OF_FLOW) {
if (disp->IsAbsolutelyPositioned()) {
frameType = NS_CSS_FRAME_TYPE_ABSOLUTE;
}
else if (NS_STYLE_FLOAT_NONE != disp->mFloats) {
frameType = NS_CSS_FRAME_TYPE_FLOATING;
} else {
NS_ASSERTION(disp->mDisplay == NS_STYLE_DISPLAY_POPUP,
"unknown out of flow frame type");
frameType = NS_CSS_FRAME_TYPE_UNKNOWN;
}
}
else {
switch (disp->mDisplay) {
case NS_STYLE_DISPLAY_BLOCK:
case NS_STYLE_DISPLAY_LIST_ITEM:
case NS_STYLE_DISPLAY_TABLE:
case NS_STYLE_DISPLAY_TABLE_CAPTION:
frameType = NS_CSS_FRAME_TYPE_BLOCK;
break;
case NS_STYLE_DISPLAY_INLINE:
case NS_STYLE_DISPLAY_INLINE_BLOCK:
case NS_STYLE_DISPLAY_MARKER:
case NS_STYLE_DISPLAY_INLINE_TABLE:
case NS_STYLE_DISPLAY_INLINE_BOX:
case NS_STYLE_DISPLAY_INLINE_GRID:
case NS_STYLE_DISPLAY_INLINE_STACK:
frameType = NS_CSS_FRAME_TYPE_INLINE;
break;
case NS_STYLE_DISPLAY_RUN_IN:
case NS_STYLE_DISPLAY_COMPACT:
// XXX need to look ahead at the frame's sibling
frameType = NS_CSS_FRAME_TYPE_BLOCK;
break;
case NS_STYLE_DISPLAY_TABLE_CELL:
case NS_STYLE_DISPLAY_TABLE_ROW_GROUP:
case NS_STYLE_DISPLAY_TABLE_COLUMN:
case NS_STYLE_DISPLAY_TABLE_COLUMN_GROUP:
case NS_STYLE_DISPLAY_TABLE_HEADER_GROUP:
case NS_STYLE_DISPLAY_TABLE_FOOTER_GROUP:
case NS_STYLE_DISPLAY_TABLE_ROW:
frameType = NS_CSS_FRAME_TYPE_INTERNAL_TABLE;
break;
case NS_STYLE_DISPLAY_NONE:
default:
frameType = NS_CSS_FRAME_TYPE_UNKNOWN;
break;
}
}
// See if the frame is replaced
if (frame->IsFrameOfType(nsIFrame::eReplacedContainsBlock)) {
frameType = NS_FRAME_REPLACED_CONTAINS_BLOCK(frameType);
} else if (frame->IsFrameOfType(nsIFrame::eReplaced)) {
frameType = NS_FRAME_REPLACED(frameType);
}
mFrameType = frameType;
}
void
nsHTMLReflowState::ComputeRelativeOffsets(const nsHTMLReflowState* cbrs,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight)
{
nsStyleCoord coord;
// Compute the 'left' and 'right' values. 'Left' moves the boxes to the right,
// and 'right' moves the boxes to the left. The computed values are always:
// left=-right
PRBool leftIsAuto = eStyleUnit_Auto == mStylePosition->mOffset.GetLeftUnit();
PRBool rightIsAuto = eStyleUnit_Auto == mStylePosition->mOffset.GetRightUnit();
// Check for percentage based values and an unconstrained containing
// block width. Treat them like 'auto'
if (NS_UNCONSTRAINEDSIZE == aContainingBlockWidth) {
if (eStyleUnit_Percent == mStylePosition->mOffset.GetLeftUnit()) {
leftIsAuto = PR_TRUE;
}
if (eStyleUnit_Percent == mStylePosition->mOffset.GetRightUnit()) {
rightIsAuto = PR_TRUE;
}
}
// If neither 'left' not 'right' are auto, then we're over-constrained and
// we ignore one of them
if (!leftIsAuto && !rightIsAuto) {
if (mCBReflowState &&
NS_STYLE_DIRECTION_RTL == mCBReflowState->mStyleVisibility->mDirection) {
leftIsAuto = PR_TRUE;
} else {
rightIsAuto = PR_TRUE;
}
}
if (leftIsAuto) {
if (rightIsAuto) {
// If both are 'auto' (their initial values), the computed values are 0
mComputedOffsets.left = mComputedOffsets.right = 0;
} else {
// 'Right' isn't 'auto' so compute its value
ComputeWidthDependentValue(aContainingBlockWidth,
mStylePosition->mOffset.GetRight(coord),
mComputedOffsets.right);
// Computed value for 'left' is minus the value of 'right'
mComputedOffsets.left = -mComputedOffsets.right;
}
} else {
NS_ASSERTION(rightIsAuto, "unexpected specified constraint");
// 'Left' isn't 'auto' so compute its value
ComputeWidthDependentValue(aContainingBlockWidth,
mStylePosition->mOffset.GetLeft(coord),
mComputedOffsets.left);
// Computed value for 'right' is minus the value of 'left'
mComputedOffsets.right = -mComputedOffsets.left;
}
// Compute the 'top' and 'bottom' values. The 'top' and 'bottom' properties
// move relatively positioned elements up and down. They also must be each
// other's negative
PRBool topIsAuto = eStyleUnit_Auto == mStylePosition->mOffset.GetTopUnit();
PRBool bottomIsAuto = eStyleUnit_Auto == mStylePosition->mOffset.GetBottomUnit();
// Check for percentage based values and a containing block height that
// depends on the content height. Treat them like 'auto'
if (NS_AUTOHEIGHT == aContainingBlockHeight) {
if (eStyleUnit_Percent == mStylePosition->mOffset.GetTopUnit()) {
topIsAuto = PR_TRUE;
}
if (eStyleUnit_Percent == mStylePosition->mOffset.GetBottomUnit()) {
bottomIsAuto = PR_TRUE;
}
}
// If neither is 'auto', 'bottom' is ignored
if (!topIsAuto && !bottomIsAuto) {
bottomIsAuto = PR_TRUE;
}
if (topIsAuto) {
if (bottomIsAuto) {
// If both are 'auto' (their initial values), the computed values are 0
mComputedOffsets.top = mComputedOffsets.bottom = 0;
} else {
// 'Bottom' isn't 'auto' so compute its value
ComputeHeightDependentValue(aContainingBlockHeight,
mStylePosition->mOffset.GetBottom(coord),
mComputedOffsets.bottom);
// Computed value for 'top' is minus the value of 'bottom'
mComputedOffsets.top = -mComputedOffsets.bottom;
}
} else {
NS_ASSERTION(bottomIsAuto, "unexpected specified constraint");
// 'Top' isn't 'auto' so compute its value
ComputeHeightDependentValue(aContainingBlockHeight,
mStylePosition->mOffset.GetTop(coord),
mComputedOffsets.top);
// Computed value for 'bottom' is minus the value of 'top'
mComputedOffsets.bottom = -mComputedOffsets.top;
}
}
nsIFrame*
nsHTMLReflowState::GetNearestContainingBlock(nsIFrame* aFrame, nscoord& aCBLeftEdge,
nscoord& aCBWidth)
{
for (aFrame = aFrame->GetParent(); aFrame && !aFrame->IsContainingBlock();
aFrame = aFrame->GetParent())
/* do nothing */;
NS_ASSERTION(aFrame, "Must find containing block somewhere");
NS_ASSERTION(aFrame != frame, "How did that happen?");
/* Now aFrame is the containing block we want */
/* Check whether the containing block is currently being reflown.
If so, use the info from the reflow state. */
const nsHTMLReflowState* state;
if (aFrame->GetStateBits() & NS_FRAME_IN_REFLOW) {
for (state = parentReflowState; state && state->frame != aFrame;
state = state->parentReflowState) {
/* do nothing */
}
} else {
state = nsnull;
}
if (state) {
aCBLeftEdge = state->mComputedBorderPadding.left;
aCBWidth = state->mComputedWidth;
} else {
/* Didn't find a reflow state for aFrame. Just compute the information we
want, on the assumption that aFrame already knows its size. This really
ought to be true by now. */
NS_ASSERTION(!(aFrame->GetStateBits() & NS_FRAME_IN_REFLOW),
"aFrame shouldn't be in reflow; we'll lie if it is");
nsMargin borderPadding = aFrame->GetUsedBorderAndPadding();
aCBLeftEdge = borderPadding.left;
aCBWidth = aFrame->GetSize().width - borderPadding.LeftRight();
}
return aFrame;
}
// When determining the hypothetical box that would have been if the element
// had been in the flow we may not be able to exactly determine both the left
// and right edges. For example, if the element is a non-replaced inline-level
// element we would have to reflow it in order to determine it desired width.
// In that case depending on the progression direction either the left or
// right edge would be marked as not being exact
struct nsHypotheticalBox {
nscoord mLeft, mRight;
nscoord mTop;
PRPackedBool mLeftIsExact, mRightIsExact;
nsHypotheticalBox() {
mLeftIsExact = mRightIsExact = PR_FALSE;
}
};
static PRBool
GetIntrinsicSizeFor(nsIFrame* aFrame, nsSize& aIntrinsicSize)
{
// See if it is an image frame
PRBool result = PR_FALSE;
// Currently the only type of replaced frame that we can get the intrinsic
// size for is an image frame
// XXX We should add back the GetReflowMetrics() function and one of the
// things should be the intrinsic size...
if (aFrame->GetType() == nsGkAtoms::imageFrame) {
nsImageFrame* imageFrame = (nsImageFrame*)aFrame;
imageFrame->GetIntrinsicImageSize(aIntrinsicSize);
result = (aIntrinsicSize != nsSize(0, 0));
}
return result;
}
/**
* aInsideBoxSizing returns the part of the horizontal padding, border,
* and margin that goes inside the edge given by -moz-box-sizing;
* aOutsideBoxSizing returns the rest.
*/
void
nsHTMLReflowState::CalculateHorizBorderPaddingMargin(
nscoord aContainingBlockWidth,
nscoord* aInsideBoxSizing,
nscoord* aOutsideBoxSizing)
{
const nsMargin& border = mStyleBorder->GetBorder();
nsMargin padding, margin;
// See if the style system can provide us the padding directly
if (!mStylePadding->GetPadding(padding)) {
nsStyleCoord left, right;
// We have to compute the left and right values
ComputeWidthDependentValue(aContainingBlockWidth,
mStylePadding->mPadding.GetLeft(left),
padding.left);
ComputeWidthDependentValue(aContainingBlockWidth,
mStylePadding->mPadding.GetRight(right),
padding.right);
}
// See if the style system can provide us the margin directly
if (!mStyleMargin->GetMargin(margin)) {
nsStyleCoord left, right;
// We have to compute the left and right values
if (eStyleUnit_Auto == mStyleMargin->mMargin.GetLeftUnit()) {
// XXX FIXME (or does CalculateBlockSideMargins do this?)
margin.left = 0; // just ignore
} else {
ComputeWidthDependentValue(aContainingBlockWidth,
mStyleMargin->mMargin.GetLeft(left),
margin.left);
}
if (eStyleUnit_Auto == mStyleMargin->mMargin.GetRightUnit()) {
// XXX FIXME (or does CalculateBlockSideMargins do this?)
margin.right = 0; // just ignore
} else {
ComputeWidthDependentValue(aContainingBlockWidth,
mStyleMargin->mMargin.GetRight(right),
margin.right);
}
}
nscoord outside =
padding.LeftRight() + border.LeftRight() + margin.LeftRight();
nscoord inside = 0;
switch (mStylePosition->mBoxSizing) {
case NS_STYLE_BOX_SIZING_BORDER:
inside += border.LeftRight();
// fall through
case NS_STYLE_BOX_SIZING_PADDING:
inside += padding.LeftRight();
}
outside -= inside;
*aInsideBoxSizing = inside;
*aOutsideBoxSizing = outside;
return;
}
/**
* Returns PR_TRUE iff a pre-order traversal of the normal child
* frames rooted at aFrame finds no non-empty frame before aDescendant.
*/
static PRBool AreAllEarlierInFlowFramesEmpty(nsIFrame* aFrame,
nsIFrame* aDescendant, PRBool* aFound) {
if (aFrame == aDescendant) {
*aFound = PR_TRUE;
return PR_TRUE;
}
if (!aFrame->IsSelfEmpty()) {
*aFound = PR_FALSE;
return PR_FALSE;
}
for (nsIFrame* f = aFrame->GetFirstChild(nsnull); f; f = f->GetNextSibling()) {
PRBool allEmpty = AreAllEarlierInFlowFramesEmpty(f, aDescendant, aFound);
if (*aFound || !allEmpty) {
return allEmpty;
}
}
*aFound = PR_FALSE;
return PR_TRUE;
}
// Calculate the hypothetical box that the element would have if it were in
// the flow. The values returned are relative to the padding edge of the
// absolute containing block
void
nsHTMLReflowState::CalculateHypotheticalBox(nsPresContext* aPresContext,
nsIFrame* aPlaceholderFrame,
nsIFrame* aContainingBlock,
nscoord aBlockLeftContentEdge,
nscoord aBlockContentWidth,
const nsHTMLReflowState* cbrs,
nsHypotheticalBox& aHypotheticalBox)
{
NS_ASSERTION(mStyleDisplay->mOriginalDisplay != NS_STYLE_DISPLAY_NONE,
"mOriginalDisplay has not been properly initialized");
// If it's a replaced element and it has a 'auto' value for 'width', see if we
// can get the intrinsic size. This will allow us to exactly determine both the
// left and right edges
PRBool isAutoWidth = mStylePosition->mWidth.GetUnit() == eStyleUnit_Auto;
nsSize intrinsicSize;
PRBool knowIntrinsicSize = PR_FALSE;
if (NS_FRAME_IS_REPLACED(mFrameType) && isAutoWidth) {
// See if we can get the intrinsic size of the element
knowIntrinsicSize = GetIntrinsicSizeFor(frame, intrinsicSize);
}
// See if we can calculate what the box width would have been if the
// element had been in the flow
nscoord boxWidth;
PRBool knowBoxWidth = PR_FALSE;
if ((NS_STYLE_DISPLAY_INLINE == mStyleDisplay->mOriginalDisplay) &&
!NS_FRAME_IS_REPLACED(mFrameType)) {
// For non-replaced inline-level elements the 'width' property doesn't apply,
// so we don't know what the width would have been without reflowing it
} else {
// It's either a replaced inline-level element or a block-level element
// Determine the total amount of horizontal border/padding/margin that
// the element would have had if it had been in the flow. Note that we
// ignore any 'auto' and 'inherit' values
nscoord insideBoxSizing, outsideBoxSizing;
CalculateHorizBorderPaddingMargin(aBlockContentWidth,
&insideBoxSizing, &outsideBoxSizing);
if (NS_FRAME_IS_REPLACED(mFrameType) && isAutoWidth) {
// It's a replaced element with an 'auto' width so the box width is
// its intrinsic size plus any border/padding/margin
if (knowIntrinsicSize) {
boxWidth = intrinsicSize.width + outsideBoxSizing + insideBoxSizing;
knowBoxWidth = PR_TRUE;
}
} else if (isAutoWidth) {
// The box width is the containing block width
boxWidth = aBlockContentWidth;
knowBoxWidth = PR_TRUE;
} else {
// We need to compute it. It's important we do this, because if it's
// percentage based this computed value may be different from the comnputed
// value calculated using the absolute containing block width
boxWidth = ComputeWidthValue(aBlockContentWidth,
insideBoxSizing, outsideBoxSizing,
mStylePosition->mWidth) +
insideBoxSizing + outsideBoxSizing;
knowBoxWidth = PR_TRUE;
}
}
// Get the 'direction' of the block
const nsStyleVisibility* blockVis = aContainingBlock->GetStyleVisibility();
// Get the placeholder x-offset and y-offset in the coordinate
// space of the block frame that contains it
// XXXbz the placeholder is not fully reflown yet if our containing block is
// relatively positioned...
nsPoint placeholderOffset = aPlaceholderFrame->GetOffsetTo(aContainingBlock);
// First, determine the hypothetical box's mTop
nsBlockFrame* blockFrame;
if (NS_SUCCEEDED(aContainingBlock->QueryInterface(kBlockFrameCID,
NS_REINTERPRET_CAST(void**, &blockFrame)))) {
// We need the immediate child of the block frame, and that may not be
// the placeholder frame
nsIFrame *blockChild =
nsLayoutUtils::FindChildContainingDescendant(blockFrame, aPlaceholderFrame);
nsBlockFrame::line_iterator lineBox = blockFrame->FindLineFor(blockChild);
// How we determine the hypothetical box depends on whether the element
// would have been inline-level or block-level
if (NS_STYLE_DISPLAY_INLINE == mStyleDisplay->mOriginalDisplay) {
// Use the top of the inline box which the placeholder lives in as the
// hypothetical box's top.
aHypotheticalBox.mTop = lineBox->mBounds.y;
} else {
// The element would have been block-level which means it would be below
// the line containing the placeholder frame, unless all the frames
// before it are empty. In that case, it would have been just before
// this line.
// XXXbz the line box is not fully reflown yet if our containing block is
// relatively positioned...
if (lineBox != blockFrame->end_lines()) {
nsIFrame * firstFrame = lineBox->mFirstChild;
PRBool found = PR_FALSE;
PRBool allEmpty = PR_TRUE;
while (firstFrame) { // See bug 223064
allEmpty = AreAllEarlierInFlowFramesEmpty(firstFrame,
aPlaceholderFrame, &found);
if (found || !allEmpty)
break;
firstFrame = firstFrame->GetNextSibling();
}
NS_ASSERTION(firstFrame, "Couldn't find placeholder!");
if (allEmpty) {
// The top of the hypothetical box is the top of the line containing
// the placeholder, since there is nothing in the line before our
// placeholder except empty frames.
aHypotheticalBox.mTop = lineBox->mBounds.y;
} else {
// The top of the hypothetical box is just below the line containing
// the placeholder.
aHypotheticalBox.mTop = lineBox->mBounds.YMost();
}
} else {
// Just use the placeholder's y-offset
aHypotheticalBox.mTop = placeholderOffset.y;
}
}
} else {
// The containing block is not a block, so it's probably something
// like a XUL box, etc.
// Just use the placeholder's y-offset
aHypotheticalBox.mTop = placeholderOffset.y;
}
// Second, determine the hypothetical box's mLeft & mRight
// To determine the left and right offsets we need to look at the block's 'direction'
if (NS_STYLE_DIRECTION_LTR == blockVis->mDirection) {
// How we determine the hypothetical box depends on whether the element
// would have been inline-level or block-level
if (NS_STYLE_DISPLAY_INLINE == mStyleDisplay->mOriginalDisplay) {
// The placeholder represents the left edge of the hypothetical box
aHypotheticalBox.mLeft = placeholderOffset.x;
} else {
aHypotheticalBox.mLeft = aBlockLeftContentEdge;
}
aHypotheticalBox.mLeftIsExact = PR_TRUE;
if (knowBoxWidth) {
aHypotheticalBox.mRight = aHypotheticalBox.mLeft + boxWidth;
aHypotheticalBox.mRightIsExact = PR_TRUE;
} else {
// We can't compute the right edge because we don't know the desired
// width. So instead use the right content edge of the block parent,
// but remember it's not exact
aHypotheticalBox.mRight = aBlockLeftContentEdge + aBlockContentWidth;
aHypotheticalBox.mRightIsExact = PR_FALSE;
}
} else {
// The placeholder represents the right edge of the hypothetical box
if (NS_STYLE_DISPLAY_INLINE == mStyleDisplay->mOriginalDisplay) {
aHypotheticalBox.mRight = placeholderOffset.x;
} else {
aHypotheticalBox.mRight = aBlockLeftContentEdge + aBlockContentWidth;
}
aHypotheticalBox.mRightIsExact = PR_TRUE;
if (knowBoxWidth) {
aHypotheticalBox.mLeft = aHypotheticalBox.mRight - boxWidth;
aHypotheticalBox.mLeftIsExact = PR_TRUE;
} else {
// We can't compute the left edge because we don't know the desired
// width. So instead use the left content edge of the block parent,
// but remember it's not exact
aHypotheticalBox.mLeft = aBlockLeftContentEdge;
aHypotheticalBox.mLeftIsExact = PR_FALSE;
}
}
// The current coordinate space is that of the nearest block to the placeholder.
// Convert to the coordinate space of the absolute containing block
// One weird thing here is that for fixed-positioned elements we want to do
// the conversion incorrectly; specifically we want to ignore any scrolling
// that may have happened;
nsPoint cbOffset;
if (mStyleDisplay->mPosition == NS_STYLE_POSITION_FIXED) {
// In this case, cbrs->frame will always be an ancestor of
// aContainingBlock, so can just walk our way up the frame tree.
// Make sure to not add positions of frames whose parent is a
// scrollFrame, since we're doing fixed positioning, which assumes
// everything is scrolled to (0,0).
cbOffset.MoveTo(0, 0);
do {
NS_ASSERTION(aContainingBlock,
"Should hit cbrs->frame before we run off the frame tree!");
cbOffset += aContainingBlock->GetPositionIgnoringScrolling();
aContainingBlock = aContainingBlock->GetParent();
} while (aContainingBlock != cbrs->frame);
} else {
cbOffset = aContainingBlock->GetOffsetTo(cbrs->frame);
}
aHypotheticalBox.mLeft += cbOffset.x;
aHypotheticalBox.mTop += cbOffset.y;
aHypotheticalBox.mRight += cbOffset.x;
// The specified offsets are relative to the absolute containing block's
// padding edge and our current values are relative to the border edge, so
// translate.
nsMargin border = cbrs->mComputedBorderPadding - cbrs->mComputedPadding;
aHypotheticalBox.mLeft -= border.left;
aHypotheticalBox.mRight -= border.right;
aHypotheticalBox.mTop -= border.top;
}
void
nsHTMLReflowState::InitAbsoluteConstraints(nsPresContext* aPresContext,
const nsHTMLReflowState* cbrs,
nscoord containingBlockWidth,
nscoord containingBlockHeight)
{
NS_PRECONDITION(containingBlockHeight != NS_AUTOHEIGHT,
"containing block height must be constrained");
// Get the placeholder frame
nsIFrame* placeholderFrame;
aPresContext->PresShell()->GetPlaceholderFrameFor(frame, &placeholderFrame);
NS_ASSERTION(nsnull != placeholderFrame, "no placeholder frame");
// Find the nearest containing block frame to the placeholder frame,
// and return its left edge and width.
nscoord cbLeftEdge, cbWidth;
nsIFrame* cbFrame = GetNearestContainingBlock(placeholderFrame, cbLeftEdge,
cbWidth);
// If both 'left' and 'right' are 'auto' or both 'top' and 'bottom' are
// 'auto', then compute the hypothetical box of where the element would
// have been if it had been in the flow
nsHypotheticalBox hypotheticalBox;
if (((eStyleUnit_Auto == mStylePosition->mOffset.GetLeftUnit()) &&
(eStyleUnit_Auto == mStylePosition->mOffset.GetRightUnit())) ||
((eStyleUnit_Auto == mStylePosition->mOffset.GetTopUnit()) &&
(eStyleUnit_Auto == mStylePosition->mOffset.GetBottomUnit()))) {
CalculateHypotheticalBox(aPresContext, placeholderFrame, cbFrame,
cbLeftEdge, cbWidth, cbrs, hypotheticalBox);
}
// Initialize the 'left' and 'right' computed offsets
// XXX Handle new 'static-position' value...
PRBool leftIsAuto = PR_FALSE, rightIsAuto = PR_FALSE;
nsStyleCoord coord;
if (eStyleUnit_Auto == mStylePosition->mOffset.GetLeftUnit()) {
mComputedOffsets.left = 0;
leftIsAuto = PR_TRUE;
} else {
ComputeWidthDependentValue(containingBlockWidth,
mStylePosition->mOffset.GetLeft(coord),
mComputedOffsets.left);
}
if (eStyleUnit_Auto == mStylePosition->mOffset.GetRightUnit()) {
mComputedOffsets.right = 0;
rightIsAuto = PR_TRUE;
} else {
ComputeWidthDependentValue(containingBlockWidth,
mStylePosition->mOffset.GetRight(coord),
mComputedOffsets.right);
}
PRUint8 direction = cbrs ? cbrs->mStyleVisibility->mDirection : NS_STYLE_DIRECTION_LTR;
// Use the horizontal component of the hypothetical box in the cases
// where it's needed.
if (leftIsAuto && rightIsAuto) {
// Use the 'direction' to dictate whether 'left' or 'right' is
// treated like 'static-position'
if (NS_STYLE_DIRECTION_LTR == direction) {
if (hypotheticalBox.mLeftIsExact) {
mComputedOffsets.left = hypotheticalBox.mLeft;
leftIsAuto = PR_FALSE;
} else {
// Well, we don't know 'left' so we have to use 'right' and
// then solve for 'left'
mComputedOffsets.right = hypotheticalBox.mRight;
rightIsAuto = PR_FALSE;
}
} else {
if (hypotheticalBox.mRightIsExact) {
mComputedOffsets.right = containingBlockWidth - hypotheticalBox.mRight;
rightIsAuto = PR_FALSE;
} else {
// Well, we don't know 'right' so we have to use 'left' and
// then solve for 'right'
mComputedOffsets.left = hypotheticalBox.mLeft;
leftIsAuto = PR_FALSE;
}
}
}
// Initialize the 'top' and 'bottom' computed offsets
PRBool topIsAuto = PR_FALSE, bottomIsAuto = PR_FALSE;
if (eStyleUnit_Auto == mStylePosition->mOffset.GetTopUnit()) {
mComputedOffsets.top = 0;
topIsAuto = PR_TRUE;
} else {
nsStyleCoord c;
ComputeHeightDependentValue(containingBlockHeight,
mStylePosition->mOffset.GetTop(c),
mComputedOffsets.top);
}
if (eStyleUnit_Auto == mStylePosition->mOffset.GetBottomUnit()) {
mComputedOffsets.bottom = 0;
bottomIsAuto = PR_TRUE;
} else {
nsStyleCoord c;
ComputeHeightDependentValue(containingBlockHeight,
mStylePosition->mOffset.GetBottom(c),
mComputedOffsets.bottom);
}
if (topIsAuto && bottomIsAuto) {
// Treat 'top' like 'static-position'
mComputedOffsets.top = hypotheticalBox.mTop;
topIsAuto = PR_FALSE;
}
PRBool widthIsAuto = eStyleUnit_Auto == mStylePosition->mWidth.GetUnit();
PRBool heightIsAuto = eStyleUnit_Auto == mStylePosition->mHeight.GetUnit();
PRBool shrinkWrap = leftIsAuto || rightIsAuto;
nsSize size =
frame->ComputeSize(rendContext,
nsSize(containingBlockWidth,
containingBlockHeight),
containingBlockWidth, // XXX or availableWidth?
nsSize(mComputedMargin.LeftRight() +
mComputedOffsets.LeftRight(),
mComputedMargin.TopBottom() +
mComputedOffsets.TopBottom()),
nsSize(mComputedBorderPadding.LeftRight() -
mComputedPadding.LeftRight(),
mComputedBorderPadding.TopBottom() -
mComputedPadding.TopBottom()),
nsSize(mComputedPadding.LeftRight(),
mComputedPadding.TopBottom()),
shrinkWrap);
mComputedWidth = size.width;
mComputedHeight = size.height;
// XXX Now that we have ComputeSize, can we condense many of the
// branches off of widthIsAuto?
if (leftIsAuto) {
// We know 'right' is not 'auto' anymore thanks to the hypothetical
// box code above.
// Solve for 'left'.
if (widthIsAuto) {
// XXXldb This, and the corresponding code in
// nsAbsoluteContainingBlock.cpp, could probably go away now that
// we always compute widths.
mComputedOffsets.left = NS_AUTOOFFSET;
} else {
mComputedOffsets.left = containingBlockWidth - mComputedMargin.left -
mComputedBorderPadding.left - mComputedWidth - mComputedBorderPadding.right -
mComputedMargin.right - mComputedOffsets.right;
}
} else if (rightIsAuto) {
// We know 'left' is not 'auto' anymore thanks to the hypothetical
// box code above.
// Solve for 'right'.
if (widthIsAuto) {
// XXXldb This, and the corresponding code in
// nsAbsoluteContainingBlock.cpp, could probably go away now that
// we always compute widths.
mComputedOffsets.right = NS_AUTOOFFSET;
} else {
mComputedOffsets.right = containingBlockWidth - mComputedOffsets.left -
mComputedMargin.left - mComputedBorderPadding.left - mComputedWidth -
mComputedBorderPadding.right - mComputedMargin.right;
}
} else {
// Neither 'left' nor 'right' is 'auto'. However, the width might
// still not fill all the available space (even though we didn't
// shrink-wrap) in case:
// * width was specified
// * we're dealing with a replaced element
// * width was constrained by min-width or max-width.
nscoord availMarginSpace = containingBlockWidth -
mComputedOffsets.LeftRight() -
mComputedMargin.LeftRight() -
mComputedBorderPadding.LeftRight() -
mComputedWidth;
PRBool marginLeftIsAuto =
eStyleUnit_Auto == mStyleMargin->mMargin.GetLeftUnit();
PRBool marginRightIsAuto =
eStyleUnit_Auto == mStyleMargin->mMargin.GetRightUnit();
if (availMarginSpace < 0 ||
(!marginLeftIsAuto && !marginRightIsAuto)) {
// We're over-constrained so use 'direction' to dictate which
// value to ignore. (And note that the spec says to ignore 'left'
// or 'right' rather than 'margin-left' or 'margin-right'.)
if (NS_STYLE_DIRECTION_LTR == direction) {
// Ignore the specified value for 'right'.
mComputedOffsets.right += availMarginSpace;
} else {
// Ignore the specified value for 'left'.
mComputedOffsets.left += availMarginSpace;
}
} else if (marginLeftIsAuto) {
if (marginRightIsAuto) {
// Both 'margin-left' and 'margin-right' are 'auto', so they get
// equal values
mComputedMargin.left = availMarginSpace / 2;
mComputedMargin.right = availMarginSpace - mComputedMargin.left;
} else {
// Just 'margin-left' is 'auto'
mComputedMargin.left = availMarginSpace - mComputedMargin.right;
}
} else {
// Just 'margin-right' is 'auto'
mComputedMargin.right = availMarginSpace - mComputedMargin.left;
}
}
if (topIsAuto) {
// solve for 'top'
if (heightIsAuto) {
mComputedOffsets.top = NS_AUTOOFFSET;
} else {
mComputedOffsets.top = containingBlockHeight - mComputedMargin.top -
mComputedBorderPadding.top - mComputedHeight - mComputedBorderPadding.bottom -
mComputedMargin.bottom - mComputedOffsets.bottom;
}
} else if (bottomIsAuto) {
// solve for 'bottom'
if (heightIsAuto) {
mComputedOffsets.bottom = NS_AUTOOFFSET;
} else {
mComputedOffsets.bottom = containingBlockHeight - mComputedOffsets.top -
mComputedMargin.top - mComputedBorderPadding.top - mComputedHeight -
mComputedBorderPadding.bottom - mComputedMargin.bottom;
}
} else {
// Neither 'top' nor 'bottom' is 'auto'.
nscoord autoHeight = containingBlockHeight -
mComputedOffsets.TopBottom() -
mComputedMargin.TopBottom() -
mComputedBorderPadding.TopBottom();
if (autoHeight < 0) {
autoHeight = 0;
}
if (mComputedHeight == NS_UNCONSTRAINEDSIZE) {
// For non-replaced elements with 'height' auto, the 'height'
// fills the remaining space.
mComputedHeight = autoHeight;
// XXX Do these need box-sizing adjustments?
if (mComputedHeight > mComputedMaxHeight)
mComputedHeight = mComputedMaxHeight;
if (mComputedHeight < mComputedMinHeight)
mComputedHeight = mComputedMinHeight;
}
// The height might still not fill all the available space in case:
// * height was specified
// * we're dealing with a replaced element
// * height was constrained by min-height or max-height.
nscoord availMarginSpace = autoHeight - mComputedHeight;
PRBool marginTopIsAuto =
eStyleUnit_Auto == mStyleMargin->mMargin.GetTopUnit();
PRBool marginBottomIsAuto =
eStyleUnit_Auto == mStyleMargin->mMargin.GetBottomUnit();
if (availMarginSpace < 0 || (!marginTopIsAuto && !marginBottomIsAuto)) {
// We're over-constrained so ignore the specified value for
// 'bottom'. (And note that the spec says to ignore 'bottom'
// rather than 'margin-bottom'.)
mComputedOffsets.bottom += availMarginSpace;
} else if (marginTopIsAuto) {
if (marginBottomIsAuto) {
// Both 'margin-top' and 'margin-bottom' are 'auto', so they get
// equal values
mComputedMargin.top = availMarginSpace / 2;
mComputedMargin.bottom = availMarginSpace - mComputedMargin.top;
} else {
// Just 'margin-top' is 'auto'
mComputedMargin.top = availMarginSpace - mComputedMargin.bottom;
}
} else {
// Just 'margin-bottom' is 'auto'
mComputedMargin.bottom = availMarginSpace - mComputedMargin.top;
}
}
}
nscoord
GetVerticalMarginBorderPadding(const nsHTMLReflowState* aReflowState)
{
nscoord result = 0;
if (!aReflowState) return result;
// zero auto margins
nsMargin margin = aReflowState->mComputedMargin;
if (NS_AUTOMARGIN == margin.top)
margin.top = 0;
if (NS_AUTOMARGIN == margin.bottom)
margin.bottom = 0;
result += margin.top + margin.bottom;
result += aReflowState->mComputedBorderPadding.top +
aReflowState->mComputedBorderPadding.bottom;
return result;
}
/* Get the height based on the viewport of the containing block specified
* in aReflowState when the containing block has mComputedHeight == NS_AUTOHEIGHT
* This will walk up the chain of containing blocks looking for a computed height
* until it finds the canvas frame, or it encounters a frame that is not a block,
* area, or scroll frame. This handles compatibility with IE (see bug 85016 and bug 219693)
*
* When we encounter scrolledContent area frames, we skip over them, since they are guaranteed to not be useful for computing the containing block.
*/
nscoord
CalcQuirkContainingBlockHeight(const nsHTMLReflowState* aCBReflowState)
{
nsHTMLReflowState* firstAncestorRS = nsnull; // a candidate for html frame
nsHTMLReflowState* secondAncestorRS = nsnull; // a candidate for body frame
// initialize the default to NS_AUTOHEIGHT as this is the containings block
// computed height when this function is called. It is possible that we
// don't alter this height especially if we are restricted to one level
nscoord result = NS_AUTOHEIGHT;
const nsHTMLReflowState* rs = aCBReflowState;
for (; rs && rs->frame; rs = (nsHTMLReflowState *)(rs->parentReflowState)) {
nsIAtom* frameType = rs->frame->GetType();
// if the ancestor is auto height then skip it and continue up if it
// is the first block/area frame and possibly the body/html
if (nsGkAtoms::blockFrame == frameType ||
nsGkAtoms::areaFrame == frameType ||
nsGkAtoms::scrollFrame == frameType) {
if (nsGkAtoms::areaFrame == frameType) {
// Skip over scrolled-content area frames
if (rs->frame->GetStyleContext()->GetPseudoType() ==
nsCSSAnonBoxes::scrolledContent) {
continue;
}
}
secondAncestorRS = firstAncestorRS;
firstAncestorRS = (nsHTMLReflowState*)rs;
// If the current frame we're looking at is positioned, we don't want to
// go any further (see bug 221784). The behavior we want here is: 1) If
// not auto-height, use this as the percentage base. 2) If auto-height,
// keep looking, unless the frame is positioned.
if (NS_AUTOHEIGHT == rs->mComputedHeight) {
if (rs->frame->GetStyleDisplay()->IsAbsolutelyPositioned()) {
break;
} else {
continue;
}
}
}
else if (nsGkAtoms::canvasFrame == frameType) {
// Use scroll frames' computed height if we have one, this will
// allow us to get viewport height for native scrollbars.
nsHTMLReflowState* scrollState = (nsHTMLReflowState *)rs->parentReflowState;
if (nsGkAtoms::scrollFrame == scrollState->frame->GetType()) {
rs = scrollState;
}
}
else if (nsGkAtoms::pageContentFrame == frameType) {
nsIFrame* prevInFlow = rs->frame->GetPrevInFlow();
// only use the page content frame for a height basis if it is the first in flow
if (prevInFlow)
break;
}
else {
break;
}
// if the ancestor is the page content frame then the percent base is
// the avail height, otherwise it is the computed height
result = (nsGkAtoms::pageContentFrame == frameType)
? rs->availableHeight : rs->mComputedHeight;
// if unconstrained - don't sutract borders - would result in huge height
if (NS_AUTOHEIGHT == result) return result;
// if we got to the canvas or page content frame, then subtract out
// margin/border/padding for the BODY and HTML elements
if ((nsGkAtoms::canvasFrame == frameType) ||
(nsGkAtoms::pageContentFrame == frameType)) {
result -= GetVerticalMarginBorderPadding(firstAncestorRS);
result -= GetVerticalMarginBorderPadding(secondAncestorRS);
#ifdef DEBUG
// make sure the first ancestor is the HTML and the second is the BODY
if (firstAncestorRS) {
nsIContent* frameContent = firstAncestorRS->frame->GetContent();
if (frameContent) {
nsIAtom *contentTag = frameContent->Tag();
NS_ASSERTION(contentTag == nsGkAtoms::html, "First ancestor is not HTML");
}
}
if (secondAncestorRS) {
nsIContent* frameContent = secondAncestorRS->frame->GetContent();
if (frameContent) {
nsIAtom *contentTag = frameContent->Tag();
NS_ASSERTION(contentTag == nsGkAtoms::body, "Second ancestor is not BODY");
}
}
#endif
}
// if we got to the html frame, then subtract out
// margin/border/padding for the BODY element
else if (nsGkAtoms::areaFrame == frameType) {
// make sure it is the body
if (nsGkAtoms::canvasFrame == rs->parentReflowState->frame->GetType()) {
result -= GetVerticalMarginBorderPadding(secondAncestorRS);
}
}
break;
}
// Make sure not to return a negative height here!
return PR_MAX(result, 0);
}
// Called by InitConstraints() to compute the containing block rectangle for
// the element. Handles the special logic for absolutely positioned elements
void
nsHTMLReflowState::ComputeContainingBlockRectangle(nsPresContext* aPresContext,
const nsHTMLReflowState* aContainingBlockRS,
nscoord& aContainingBlockWidth,
nscoord& aContainingBlockHeight)
{
// Unless the element is absolutely positioned, the containing block is
// formed by the content edge of the nearest block-level ancestor
aContainingBlockWidth = aContainingBlockRS->mComputedWidth;
aContainingBlockHeight = aContainingBlockRS->mComputedHeight;
if (NS_FRAME_GET_TYPE(mFrameType) == NS_CSS_FRAME_TYPE_ABSOLUTE) {
// See if the ancestor is block-level or inline-level
if (NS_FRAME_GET_TYPE(aContainingBlockRS->mFrameType) == NS_CSS_FRAME_TYPE_INLINE) {
// Base our size on the actual size of the frame. In cases when this is
// completely bogus (eg initial reflow), this code shouldn't even be
// called, since the code in nsPositionedInlineFrame::Reflow will pass in
// the containing block dimensions to our constructor.
// XXXbz we should be taking the in-flows into account too, but
// that's very hard.
nsMargin computedBorder = aContainingBlockRS->mComputedBorderPadding -
aContainingBlockRS->mComputedPadding;
aContainingBlockWidth = aContainingBlockRS->frame->GetRect().width -
computedBorder.LeftRight();;
NS_ASSERTION(aContainingBlockWidth >= 0,
"Negative containing block width!");
aContainingBlockHeight = aContainingBlockRS->frame->GetRect().height -
computedBorder.TopBottom();
NS_ASSERTION(aContainingBlockHeight >= 0,
"Negative containing block height!");
} else {
// If the ancestor is block-level, the containing block is formed by the
// padding edge of the ancestor
aContainingBlockWidth += aContainingBlockRS->mComputedPadding.LeftRight();
// If the containing block is the initial containing block and it has a
// height that depends on its content, then use the viewport height instead.
// This gives us a reasonable value against which to compute percentage
// based heights and to do bottom relative positioning
if ((NS_AUTOHEIGHT == aContainingBlockHeight) &&
nsLayoutUtils::IsInitialContainingBlock(aContainingBlockRS->frame)) {
// Use the viewport height as the containing block height
const nsHTMLReflowState* rs = aContainingBlockRS->parentReflowState;
while (rs) {
aContainingBlockHeight = rs->mComputedHeight;
rs = rs->parentReflowState;
}
} else {
aContainingBlockHeight +=
aContainingBlockRS->mComputedPadding.TopBottom();
}
}
} else {
// an element in quirks mode gets a containing block based on looking for a
// parent with a non-auto height if the element has a percent height
if (NS_AUTOHEIGHT == aContainingBlockHeight) {
if (eCompatibility_NavQuirks == aPresContext->CompatibilityMode() &&
mStylePosition->mHeight.GetUnit() == eStyleUnit_Percent) {
aContainingBlockHeight = CalcQuirkContainingBlockHeight(aContainingBlockRS);
}
}
}
}
// Prefs callback to pick up changes
PR_STATIC_CALLBACK(int)
PrefsChanged(const char *aPrefName, void *instance)
{
sBlinkIsAllowed =
nsContentUtils::GetBoolPref("browser.blink_allowed", sBlinkIsAllowed);
return 0; /* PREF_OK */
}
// Check to see if |text-decoration: blink| is allowed. The first time
// called, register the callback and then force-load the pref. After that,
// just use the cached value.
static PRBool BlinkIsAllowed(void)
{
if (!sPrefIsLoaded) {
// Set up a listener and check the initial value
nsContentUtils::RegisterPrefCallback("browser.blink_allowed", PrefsChanged,
nsnull);
PrefsChanged(nsnull, nsnull);
sPrefIsLoaded = PR_TRUE;
}
return sBlinkIsAllowed;
}
#ifdef FONT_LEADING_APIS_V2
static eNormalLineHeightControl GetNormalLineHeightCalcControl(void)
{
if (sNormalLineHeightControl == eUninitialized) {
// browser.display.normal_lineheight_calc_control is not user
// changeable, so no need to register callback for it.
sNormalLineHeightControl =
NS_STATIC_CAST(eNormalLineHeightControl,
nsContentUtils::GetIntPref("browser.display.normal_lineheight_calc_control", eNoExternalLeading));
}
return sNormalLineHeightControl;
}
#endif
// XXX refactor this code to have methods for each set of properties
// we are computing: width,height,line-height; margin; offsets
void
nsHTMLReflowState::InitConstraints(nsPresContext* aPresContext,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight,
const nsMargin* aBorder,
const nsMargin* aPadding)
{
// If this is the root frame, then set the computed width and
// height equal to the available space
if (nsnull == parentReflowState) {
// XXXldb This doesn't mean what it used to!
InitOffsets(aContainingBlockWidth, aBorder, aPadding);
// Override mComputedMargin since reflow roots start from the
// frame's boundary, which is inside the margin.
mComputedMargin.SizeTo(0, 0, 0, 0);
mComputedOffsets.SizeTo(0, 0, 0, 0);
mComputedWidth = availableWidth - mComputedBorderPadding.LeftRight();
if (mComputedWidth < 0)
mComputedWidth = 0;
if (availableHeight != NS_UNCONSTRAINEDSIZE) {
mComputedHeight = availableHeight - mComputedBorderPadding.TopBottom();
if (mComputedHeight < 0)
mComputedHeight = 0;
} else {
mComputedHeight = NS_UNCONSTRAINEDSIZE;
}
mComputedMinWidth = mComputedMinHeight = 0;
mComputedMaxWidth = mComputedMaxHeight = NS_UNCONSTRAINEDSIZE;
} else {
// Get the containing block reflow state
const nsHTMLReflowState* cbrs = mCBReflowState;
NS_ASSERTION(nsnull != cbrs, "no containing block");
// If we weren't given a containing block width and height, then
// compute one
if (aContainingBlockWidth == -1) {
ComputeContainingBlockRectangle(aPresContext, cbrs, aContainingBlockWidth,
aContainingBlockHeight);
}
#if 0
nsFrame::ListTag(stdout, frame); printf(": cb=");
nsFrame::ListTag(stdout, cbrs->frame); printf(" size=%d,%d\n", aContainingBlockWidth, aContainingBlockHeight);
#endif
// See if the containing block height is based on the size of its
// content
nsIAtom* fType;
if (NS_AUTOHEIGHT == aContainingBlockHeight) {
// See if the containing block is (1) a scrolled frame, i.e. its
// parent is a scroll frame. The presence of the intervening
// frame (that the scroll frame scrolls) needs to be hidden from
// the containingBlockHeight calcuation, or (2) a cell frame which needs
// to use the mComputedHeight of the cell instead of what the cell block passed in.
if (cbrs->parentReflowState) {
nsIFrame* f = cbrs->parentReflowState->frame;
fType = f->GetType();
if (nsGkAtoms::scrollFrame == fType) {
// Use the scroll frame's computed height instead
aContainingBlockHeight = cbrs->parentReflowState->mComputedHeight;
}
else {
fType = cbrs->frame->GetType();
if (IS_TABLE_CELL(fType)) {
// use the cell's computed height
aContainingBlockHeight = cbrs->mComputedHeight;
}
}
}
}
InitOffsets(aContainingBlockWidth, aBorder, aPadding);
nsStyleUnit heightUnit = mStylePosition->mHeight.GetUnit();
// Check for a percentage based height and a containing block height
// that depends on the content height
// XXX twiddling heightUnit doesn't help anymore
if (eStyleUnit_Percent == heightUnit) {
if (NS_AUTOHEIGHT == aContainingBlockHeight) {
// this if clause enables %-height on replaced inline frames,
// such as images. See bug 54119. The else clause "heightUnit = eStyleUnit_Auto;"
// used to be called exclusively.
if (NS_FRAME_REPLACED(NS_CSS_FRAME_TYPE_INLINE) == mFrameType ||
NS_FRAME_REPLACED_CONTAINS_BLOCK(
NS_CSS_FRAME_TYPE_INLINE) == mFrameType) {
// Get the containing block reflow state
NS_ASSERTION(nsnull != cbrs, "no containing block");
// in quirks mode, get the cb height using the special quirk method
if (eCompatibility_NavQuirks == aPresContext->CompatibilityMode()) {
if (!IS_TABLE_CELL(fType)) {
aContainingBlockHeight = CalcQuirkContainingBlockHeight(cbrs);
if (aContainingBlockHeight == NS_AUTOHEIGHT) {
heightUnit = eStyleUnit_Auto;
}
}
else {
heightUnit = eStyleUnit_Auto;
}
}
// in standard mode, use the cb height. if it's "auto", as will be the case
// by default in BODY, use auto height as per CSS2 spec.
else
{
if (NS_AUTOHEIGHT != cbrs->mComputedHeight)
aContainingBlockHeight = cbrs->mComputedHeight;
else
heightUnit = eStyleUnit_Auto;
}
}
else {
// default to interpreting the height like 'auto'
heightUnit = eStyleUnit_Auto;
}
}
}
// Compute our offsets if the element is relatively positioned. We need
// the correct containing block width and height here, which is why we need
// to do it after all the quirks-n-such above.
if (NS_STYLE_POSITION_RELATIVE == mStyleDisplay->mPosition) {
ComputeRelativeOffsets(cbrs, aContainingBlockWidth, aContainingBlockHeight);
} else {
// Initialize offsets to 0
mComputedOffsets.SizeTo(0, 0, 0, 0);
}
// Calculate the computed values for min and max properties. Note that
// this MUST come after we've computed our border and padding.
ComputeMinMaxValues(aContainingBlockWidth, aContainingBlockHeight, cbrs);
// Calculate the computed width and height. This varies by frame type
if (NS_CSS_FRAME_TYPE_INTERNAL_TABLE == mFrameType) {
// Internal table elements. The rules vary depending on the type.
// Calculate the computed width
PRBool rowOrRowGroup = PR_FALSE;
nsStyleUnit widthUnit = mStylePosition->mWidth.GetUnit();
if ((NS_STYLE_DISPLAY_TABLE_ROW == mStyleDisplay->mDisplay) ||
(NS_STYLE_DISPLAY_TABLE_ROW_GROUP == mStyleDisplay->mDisplay)) {
// 'width' property doesn't apply to table rows and row groups
widthUnit = eStyleUnit_Auto;
rowOrRowGroup = PR_TRUE;
}
if (eStyleUnit_Auto == widthUnit) {
mComputedWidth = availableWidth;
if ((mComputedWidth != NS_UNCONSTRAINEDSIZE) && !rowOrRowGroup){
// Internal table elements don't have margins. Only tables and
// cells have border and padding
mComputedWidth -= mComputedBorderPadding.left +
mComputedBorderPadding.right;
}
} else {
NS_ASSERTION(widthUnit == mStylePosition->mWidth.GetUnit(),
"unexpected width unit change");
mComputedWidth = ComputeWidthValue(aContainingBlockWidth,
mStylePosition->mBoxSizing,
mStylePosition->mWidth);
}
// Calculate the computed height
if ((NS_STYLE_DISPLAY_TABLE_COLUMN == mStyleDisplay->mDisplay) ||
(NS_STYLE_DISPLAY_TABLE_COLUMN_GROUP == mStyleDisplay->mDisplay)) {
// 'height' property doesn't apply to table columns and column groups
heightUnit = eStyleUnit_Auto;
}
if (eStyleUnit_Auto == heightUnit) {
mComputedHeight = NS_AUTOHEIGHT;
} else {
NS_ASSERTION(heightUnit == mStylePosition->mHeight.GetUnit(),
"unexpected height unit change");
ComputeHeightDependentValue(aContainingBlockHeight,
mStylePosition->mHeight,
mComputedHeight);
}
// Doesn't apply to table elements
mComputedMinWidth = mComputedMinHeight = 0;
mComputedMaxWidth = mComputedMaxHeight = NS_UNCONSTRAINEDSIZE;
} else if (NS_FRAME_GET_TYPE(mFrameType) == NS_CSS_FRAME_TYPE_ABSOLUTE) {
// XXX not sure if this belongs here or somewhere else - cwk
InitAbsoluteConstraints(aPresContext, cbrs, aContainingBlockWidth,
aContainingBlockHeight);
} else {
PRBool isBlock =
NS_CSS_FRAME_TYPE_BLOCK == NS_FRAME_GET_TYPE(mFrameType);
nsSize size =
frame->ComputeSize(rendContext,
nsSize(aContainingBlockWidth,
aContainingBlockHeight),
availableWidth,
nsSize(mComputedMargin.LeftRight(),
mComputedMargin.TopBottom()),
nsSize(mComputedBorderPadding.LeftRight() -
mComputedPadding.LeftRight(),
mComputedBorderPadding.TopBottom() -
mComputedPadding.TopBottom()),
nsSize(mComputedPadding.LeftRight(),
mComputedPadding.TopBottom()),
!isBlock);
mComputedWidth = size.width;
mComputedHeight = size.height;
if (isBlock)
CalculateBlockSideMargins(availableWidth, mComputedWidth);
}
}
// Check for blinking text and permission to display it
mFlags.mBlinks = (parentReflowState && parentReflowState->mFlags.mBlinks);
if (!mFlags.mBlinks && BlinkIsAllowed()) {
const nsStyleTextReset* st = frame->GetStyleTextReset();
mFlags.mBlinks =
((st->mTextDecoration & NS_STYLE_TEXT_DECORATION_BLINK) != 0);
}
}
void
nsCSSOffsetState::InitOffsets(nscoord aContainingBlockWidth,
const nsMargin *aBorder,
const nsMargin *aPadding)
{
// Compute margins from the specified margin style information. These
// become the default computed values, and may be adjusted below
// XXX fix to provide 0,0 for the top&bottom margins for
// inline-non-replaced elements
ComputeMargin(aContainingBlockWidth);
const nsStyleDisplay *disp = frame->GetStyleDisplay();
PRBool isThemed = frame->IsThemed(disp);
nsPresContext *presContext = frame->PresContext();
if (isThemed &&
presContext->GetTheme()->GetWidgetPadding(presContext->DeviceContext(),
frame, disp->mAppearance,
&mComputedPadding)) {
mComputedPadding.top = presContext->DevPixelsToAppUnits(mComputedPadding.top);
mComputedPadding.right = presContext->DevPixelsToAppUnits(mComputedPadding.right);
mComputedPadding.bottom = presContext->DevPixelsToAppUnits(mComputedPadding.bottom);
mComputedPadding.left = presContext->DevPixelsToAppUnits(mComputedPadding.left);
}
else if (aPadding) { // padding is an input arg
mComputedPadding.top = aPadding->top;
mComputedPadding.right = aPadding->right;
mComputedPadding.bottom = aPadding->bottom;
mComputedPadding.left = aPadding->left;
}
else {
ComputePadding(aContainingBlockWidth);
}
if (isThemed) {
presContext->GetTheme()->GetWidgetBorder(presContext->DeviceContext(),
frame, disp->mAppearance,
&mComputedBorderPadding);
mComputedBorderPadding.top =
presContext->DevPixelsToAppUnits(mComputedBorderPadding.top);
mComputedBorderPadding.right =
presContext->DevPixelsToAppUnits(mComputedBorderPadding.right);
mComputedBorderPadding.bottom =
presContext->DevPixelsToAppUnits(mComputedBorderPadding.bottom);
mComputedBorderPadding.left =
presContext->DevPixelsToAppUnits(mComputedBorderPadding.left);
}
else if (aBorder) { // border is an input arg
mComputedBorderPadding = *aBorder;
}
else {
mComputedBorderPadding = frame->GetStyleBorder()->GetBorder();
}
mComputedBorderPadding += mComputedPadding;
if (frame->GetType() == nsGkAtoms::tableFrame) {
nsTableFrame *tableFrame = NS_STATIC_CAST(nsTableFrame*, frame);
if (tableFrame->IsBorderCollapse()) {
// border-collapsed tables don't use any of their padding, and
// only part of their border. We need to do this here before we
// try to do anything like handling 'auto' widths,
// '-moz-box-sizing', or 'auto' margins.
mComputedPadding.SizeTo(0,0,0,0);
mComputedBorderPadding = tableFrame->GetIncludedOuterBCBorder();
}
}
}
// This code enforces section 10.3.3 of the CSS2 spec for this formula:
//
// 'margin-left' + 'border-left-width' + 'padding-left' + 'width' +
// 'padding-right' + 'border-right-width' + 'margin-right'
// = width of containing block
//
// Note: the width unit is not auto when this is called
void
nsHTMLReflowState::CalculateBlockSideMargins(nscoord aAvailWidth,
nscoord aComputedWidth)
{
NS_ASSERTION(NS_UNCONSTRAINEDSIZE != aComputedWidth &&
NS_UNCONSTRAINEDSIZE != aAvailWidth,
"this shouldn't happen anymore");
nscoord sum = mComputedMargin.left + mComputedBorderPadding.left +
aComputedWidth + mComputedBorderPadding.right + mComputedMargin.right;
if (sum == aAvailWidth)
// The sum is already correct
return;
// Determine the left and right margin values. The width value
// remains constant while we do this.
// Calculate how much space is available for margins
nscoord availMarginSpace = aAvailWidth - sum;
// If the available margin space is negative, then don't follow the
// usual overconstraint rules.
if (availMarginSpace < 0) {
if (mCBReflowState &&
mCBReflowState->mStyleVisibility->mDirection == NS_STYLE_DIRECTION_RTL) {
mComputedMargin.left += availMarginSpace;
} else {
mComputedMargin.right += availMarginSpace;
}
return;
}
// The css2 spec clearly defines how block elements should behave
// in section 10.3.3.
PRBool isAutoLeftMargin =
eStyleUnit_Auto == mStyleMargin->mMargin.GetLeftUnit();
PRBool isAutoRightMargin =
eStyleUnit_Auto == mStyleMargin->mMargin.GetRightUnit();
if (!isAutoLeftMargin && !isAutoRightMargin) {
// Neither margin is 'auto' so we're over constrained. Use the
// 'direction' property of the parent to tell which margin to
// ignore
// First check if there is an HTML alignment that we should honor
const nsHTMLReflowState* prs = parentReflowState;
if (frame->GetType() == nsGkAtoms::tableFrame) {
NS_ASSERTION(prs->frame->GetType() == nsGkAtoms::tableOuterFrame,
"table not inside outer table");
// Center the table within the outer table based on the alignment
// of the outer table's parent.
prs = prs->parentReflowState;
}
if (prs &&
(prs->mStyleText->mTextAlign == NS_STYLE_TEXT_ALIGN_MOZ_LEFT ||
prs->mStyleText->mTextAlign == NS_STYLE_TEXT_ALIGN_MOZ_CENTER ||
prs->mStyleText->mTextAlign == NS_STYLE_TEXT_ALIGN_MOZ_RIGHT)) {
isAutoLeftMargin =
prs->mStyleText->mTextAlign != NS_STYLE_TEXT_ALIGN_MOZ_LEFT;
isAutoRightMargin =
prs->mStyleText->mTextAlign != NS_STYLE_TEXT_ALIGN_MOZ_RIGHT;
}
// Otherwise apply the CSS rules, and ignore one margin by forcing
// it to 'auto', depending on 'direction'.
else if (mCBReflowState &&
NS_STYLE_DIRECTION_RTL == mCBReflowState->mStyleVisibility->mDirection) {
isAutoLeftMargin = PR_TRUE;
}
else {
isAutoRightMargin = PR_TRUE;
}
}
// Logic which is common to blocks and tables
if (isAutoLeftMargin) {
if (isAutoRightMargin) {
// Both margins are 'auto' so their computed values are equal
mComputedMargin.left = availMarginSpace / 2;
mComputedMargin.right = availMarginSpace - mComputedMargin.left;
} else {
mComputedMargin.left += availMarginSpace;
}
} else if (isAutoRightMargin) {
mComputedMargin.right += availMarginSpace;
}
}
#define NORMAL_LINE_HEIGHT_FACTOR 1.2f // in term of emHeight
// For "normal" we use the font's normal line height (em height + leading).
// If both internal leading and external leading specified by font itself
// are zeros, we should compensate this by creating extra (external) leading
// in eCompensateLeading mode. This is necessary because without this
// compensation, normal line height might looks too tight.
// For risk management, we use preference to control the behavior, and
// eNoExternalLeading is the old behavior.
static nscoord
GetNormalLineHeight(nsIFontMetrics* aFontMetrics)
{
NS_PRECONDITION(nsnull != aFontMetrics, "no font metrics");
nscoord normalLineHeight;
#ifdef FONT_LEADING_APIS_V2
nscoord externalLeading, internalLeading, emHeight;
aFontMetrics->GetExternalLeading(externalLeading);
aFontMetrics->GetInternalLeading(internalLeading);
aFontMetrics->GetEmHeight(emHeight);
switch (GetNormalLineHeightCalcControl()) {
case eIncludeExternalLeading:
normalLineHeight = emHeight+ internalLeading + externalLeading;
break;
case eCompensateLeading:
if (!internalLeading && !externalLeading)
normalLineHeight = NSToCoordRound(emHeight * NORMAL_LINE_HEIGHT_FACTOR);
else
normalLineHeight = emHeight+ internalLeading + externalLeading;
break;
default:
//case eNoExternalLeading:
normalLineHeight = emHeight + internalLeading;
}
#else
aFontMetrics->GetNormalLineHeight(normalLineHeight);
#endif // FONT_LEADING_APIS_V2
return normalLineHeight;
}
// Need only one of aRenderingContext and aDeviceContext
static nscoord
ComputeLineHeight(nsIRenderingContext* aRenderingContext,
nsIDeviceContext* aDeviceContext,
nsStyleContext* aStyleContext)
{
NS_PRECONDITION(aRenderingContext || aDeviceContext,
"Need to have a way of getting a device context");
nscoord lineHeight;
const nsStyleFont* font = aStyleContext->GetStyleFont();
const nsStyleCoord& lhCoord = aStyleContext->GetStyleText()->mLineHeight;
nsStyleUnit unit = lhCoord.GetUnit();
if (unit == eStyleUnit_Coord) {
// For length values just use the pre-computed value
lineHeight = lhCoord.GetCoordValue();
} else if (unit == eStyleUnit_Factor) {
// For factor units the computed value of the line-height property
// is found by multiplying the factor by the font's computed size
// (adjusted for min-size prefs and text zoom).
float factor = lhCoord.GetFactorValue();
lineHeight = NSToCoordRound(factor * font->mFont.size);
} else {
NS_ASSERTION(eStyleUnit_Normal == unit, "bad unit");
nsCOMPtr<nsIDeviceContext> deviceContext = aDeviceContext;
if (NS_UNLIKELY(!deviceContext)) {
aRenderingContext->GetDeviceContext(*getter_AddRefs(deviceContext));
}
const nsStyleVisibility* vis = aStyleContext->GetStyleVisibility();
nsCOMPtr<nsIFontMetrics> fm;
deviceContext->GetMetricsFor(font->mFont, vis->mLangGroup,
*getter_AddRefs(fm));
lineHeight = GetNormalLineHeight(fm);
}
return lineHeight;
}
nscoord
nsHTMLReflowState::CalcLineHeight(nsIRenderingContext* aRenderingContext,
nsIFrame* aFrame)
{
NS_ASSERTION(aFrame && aFrame->GetStyleContext(),
"Bogus data passed in to CalcLineHeight");
nscoord lineHeight = ComputeLineHeight(aRenderingContext, nsnull,
aFrame->GetStyleContext());
NS_ASSERTION(lineHeight >= 0, "ComputeLineHeight screwed up");
return lineHeight;
}
nscoord
nsHTMLReflowState::CalcLineHeight(nsStyleContext* aStyleContext,
nsIDeviceContext* aDeviceContext)
{
NS_PRECONDITION(aStyleContext, "Must have a style context");
NS_PRECONDITION(aDeviceContext, "Must have a device context");
nscoord lineHeight = ComputeLineHeight(nsnull, aDeviceContext,
aStyleContext);
NS_ASSERTION(lineHeight >= 0, "ComputeLineHeight screwed up");
return lineHeight;
}
/* static */
void
nsCSSOffsetState::DestroyMarginFunc(void* aFrame,
nsIAtom* aPropertyName,
void* aPropertyValue,
void* aDtorData)
{
delete NS_STATIC_CAST(nsMargin*, aPropertyValue);
}
void
nsCSSOffsetState::ComputeMargin(nscoord aContainingBlockWidth)
{
// If style style can provide us the margin directly, then use it.
const nsStyleMargin *styleMargin = frame->GetStyleMargin();
if (!styleMargin->GetMargin(mComputedMargin)) {
// We have to compute the value
if (NS_UNCONSTRAINEDSIZE == aContainingBlockWidth) {
mComputedMargin.left = 0;
mComputedMargin.right = 0;
if (eStyleUnit_Coord == styleMargin->mMargin.GetLeftUnit()) {
nsStyleCoord left;
styleMargin->mMargin.GetLeft(left),
mComputedMargin.left = left.GetCoordValue();
}
if (eStyleUnit_Coord == styleMargin->mMargin.GetRightUnit()) {
nsStyleCoord right;
styleMargin->mMargin.GetRight(right),
mComputedMargin.right = right.GetCoordValue();
}
} else {
nsStyleCoord left, right;
ComputeWidthDependentValue(aContainingBlockWidth,
styleMargin->mMargin.GetLeft(left),
mComputedMargin.left);
ComputeWidthDependentValue(aContainingBlockWidth,
styleMargin->mMargin.GetRight(right),
mComputedMargin.right);
}
nsStyleCoord top, bottom;
// According to the CSS2 spec, margin percentages are
// calculated with respect to the *width* of the containing
// block, even for margin-top and margin-bottom.
// XXX This isn't true for page boxes, if we implement them.
ComputeWidthDependentValue(aContainingBlockWidth,
styleMargin->mMargin.GetTop(top),
mComputedMargin.top);
ComputeWidthDependentValue(aContainingBlockWidth,
styleMargin->mMargin.GetBottom(bottom),
mComputedMargin.bottom);
// XXX We need to include 'auto' horizontal margins in this too!
frame->SetProperty(nsGkAtoms::usedMarginProperty,
new nsMargin(mComputedMargin),
DestroyMarginFunc);
}
}
void
nsCSSOffsetState::ComputePadding(nscoord aContainingBlockWidth)
{
// If style can provide us the padding directly, then use it.
const nsStylePadding *stylePadding = frame->GetStylePadding();
if (!stylePadding->GetPadding(mComputedPadding)) {
// We have to compute the value
nsStyleCoord left, right, top, bottom;
ComputeWidthDependentValue(aContainingBlockWidth,
stylePadding->mPadding.GetLeft(left),
mComputedPadding.left);
ComputeWidthDependentValue(aContainingBlockWidth,
stylePadding->mPadding.GetRight(right),
mComputedPadding.right);
// According to the CSS2 spec, percentages are calculated with respect to
// containing block width for padding-top and padding-bottom
ComputeWidthDependentValue(aContainingBlockWidth,
stylePadding->mPadding.GetTop(top),
mComputedPadding.top);
ComputeWidthDependentValue(aContainingBlockWidth,
stylePadding->mPadding.GetBottom(bottom),
mComputedPadding.bottom);
frame->SetProperty(nsGkAtoms::usedPaddingProperty,
new nsMargin(mComputedPadding),
DestroyMarginFunc);
}
// a table row/col group, row/col doesn't have padding
// XXXldb Neither do border-collapse tables.
nsIAtom* frameType = frame->GetType();
if (nsGkAtoms::tableRowGroupFrame == frameType ||
nsGkAtoms::tableColGroupFrame == frameType ||
nsGkAtoms::tableRowFrame == frameType ||
nsGkAtoms::tableColFrame == frameType) {
mComputedPadding.top = 0;
mComputedPadding.right = 0;
mComputedPadding.bottom = 0;
mComputedPadding.left = 0;
}
}
void
nsHTMLReflowState::ApplyMinMaxConstraints(nscoord* aFrameWidth,
nscoord* aFrameHeight) const
{
if (aFrameWidth) {
if (NS_UNCONSTRAINEDSIZE != mComputedMaxWidth) {
*aFrameWidth = PR_MIN(*aFrameWidth, mComputedMaxWidth);
}
*aFrameWidth = PR_MAX(*aFrameWidth, mComputedMinWidth);
}
if (aFrameHeight) {
if (NS_UNCONSTRAINEDSIZE != mComputedMaxHeight) {
*aFrameHeight = PR_MIN(*aFrameHeight, mComputedMaxHeight);
}
*aFrameHeight = PR_MAX(*aFrameHeight, mComputedMinHeight);
}
}
void
nsHTMLReflowState::ComputeMinMaxValues(nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight,
const nsHTMLReflowState* aContainingBlockRS)
{
mComputedMinWidth = ComputeWidthValue(aContainingBlockWidth,
mStylePosition->mBoxSizing,
mStylePosition->mMinWidth);
if (eStyleUnit_Null == mStylePosition->mMaxWidth.GetUnit()) {
// Specified value of 'none'
mComputedMaxWidth = NS_UNCONSTRAINEDSIZE; // no limit
} else {
mComputedMaxWidth = ComputeWidthValue(aContainingBlockWidth,
mStylePosition->mBoxSizing,
mStylePosition->mMaxWidth);
}
// If the computed value of 'min-width' is greater than the value of
// 'max-width', 'max-width' is set to the value of 'min-width'
if (mComputedMinWidth > mComputedMaxWidth) {
mComputedMaxWidth = mComputedMinWidth;
}
// Check for percentage based values and a containing block height that
// depends on the content height. Treat them like 'auto'
if ((NS_AUTOHEIGHT == aContainingBlockHeight) &&
(eStyleUnit_Percent == mStylePosition->mMinHeight.GetUnit())) {
mComputedMinHeight = 0;
} else {
ComputeHeightDependentValue(aContainingBlockHeight,
mStylePosition->mMinHeight, mComputedMinHeight);
}
nsStyleUnit maxHeightUnit = mStylePosition->mMaxHeight.GetUnit();
if (eStyleUnit_Null == maxHeightUnit) {
// Specified value of 'none'
mComputedMaxHeight = NS_UNCONSTRAINEDSIZE; // no limit
} else {
// Check for percentage based values and a containing block height that
// depends on the content height. Treat them like 'auto'
if ((NS_AUTOHEIGHT == aContainingBlockHeight) &&
(eStyleUnit_Percent == maxHeightUnit)) {
mComputedMaxHeight = NS_UNCONSTRAINEDSIZE;
} else {
ComputeHeightDependentValue(aContainingBlockHeight,
mStylePosition->mMaxHeight, mComputedMaxHeight);
}
}
// If the computed value of 'min-height' is greater than the value of
// 'max-height', 'max-height' is set to the value of 'min-height'
if (mComputedMinHeight > mComputedMaxHeight) {
mComputedMaxHeight = mComputedMinHeight;
}
}
void
nsHTMLReflowState::SetTruncated(const nsHTMLReflowMetrics& aMetrics,
nsReflowStatus* aStatus) const
{
if (availableHeight != NS_UNCONSTRAINEDSIZE &&
availableHeight < aMetrics.height &&
!mFlags.mIsTopOfPage) {
*aStatus |= NS_FRAME_TRUNCATED;
} else {
*aStatus &= ~NS_FRAME_TRUNCATED;
}
}