/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: NPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Netscape 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/NPL/
*
* 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 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 NPL, 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 NPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsCOMPtr.h"
#include "nsStyleConsts.h"
#include "nsCSSAnonBoxes.h"
#include "nsFrame.h"
#include "nsIContent.h"
#include "nsHTMLAtoms.h"
#include "nsIPresContext.h"
#include "nsIPresShell.h"
#include "nsLayoutAtoms.h"
#include "nsIDeviceContext.h"
#include "nsIRenderingContext.h"
#include "nsIFontMetrics.h"
#include "nsBlockFrame.h"
#include "nsLineBox.h"
#include "nsImageFrame.h"
#include "nsIPref.h"
#include "nsIServiceManager.h"
#include "nsIPercentHeightObserver.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
#ifdef DEBUG
const char*
nsHTMLReflowState::ReasonToString(nsReflowReason aReason)
{
static const char* reasons[] = {
"initial", "incremental", "resize", "style-change", "dirty"
};
return reasons[aReason];
}
#endif
nsHTMLReflowState::nsHTMLReflowState(const nsHTMLReflowState& aOther)
{
// Use assignment operator below.
*this = aOther;
}
nsHTMLReflowState&
nsHTMLReflowState::operator=(const nsHTMLReflowState &aOther)
{
// Copy everything.
// XXX This won't work anymore if someone adds member variables that
// have nontrivial constructors or assignment operators (e.g.,
// nsCOMPtr).
memcpy(this, &aOther, sizeof(*this));
// Fix up the |mCBReflowState| member, which should continue to point
// to |this|.
if (aOther.mCBReflowState == &aOther)
mCBReflowState = this;
return *this;
}
// Initialize a root reflow state with a rendering context to
// use for measuring things.
nsHTMLReflowState::nsHTMLReflowState(nsIPresContext* aPresContext,
nsIFrame* aFrame,
nsReflowReason aReason,
nsIRenderingContext* aRenderingContext,
const nsSize& aAvailableSpace)
: mReflowDepth(0)
{
NS_PRECONDITION(nsnull != aRenderingContext, "no rendering context");
parentReflowState = nsnull;
frame = aFrame;
reason = aReason;
path = nsnull;
availableWidth = aAvailableSpace.width;
availableHeight = aAvailableSpace.height;
rendContext = aRenderingContext;
mSpaceManager = nsnull;
mLineLayout = nsnull;
mFlags.mSpecialHeightReflow = PR_FALSE;
mFlags.mIsTopOfPage = PR_FALSE;
mFlags.mUnused = 0;
mPercentHeightObserver = nsnull;
mPercentHeightReflowInitiator = nsnull;
Init(aPresContext);
#ifdef IBMBIDI
mFlags.mVisualBidiFormControl = IsBidiFormControl(aPresContext);
mRightEdge = NS_UNCONSTRAINEDSIZE;
#endif
}
// Initialize a root reflow state for an incremental
// reflow.
nsHTMLReflowState::nsHTMLReflowState(nsIPresContext* aPresContext,
nsIFrame* aFrame,
nsReflowPath* aReflowPath,
nsIRenderingContext* aRenderingContext,
const nsSize& aAvailableSpace)
: mReflowDepth(0)
{
NS_PRECONDITION(nsnull != aRenderingContext, "no rendering context");
reason = eReflowReason_Incremental;
path = aReflowPath;
parentReflowState = nsnull;
frame = aFrame;
availableWidth = aAvailableSpace.width;
availableHeight = aAvailableSpace.height;
rendContext = aRenderingContext;
mSpaceManager = nsnull;
mLineLayout = nsnull;
mFlags.mSpecialHeightReflow = PR_FALSE;
mFlags.mIsTopOfPage = PR_FALSE;
mFlags.mUnused = 0;
mPercentHeightObserver = nsnull;
mPercentHeightReflowInitiator = nsnull;
Init(aPresContext);
#ifdef IBMBIDI
mFlags.mVisualBidiFormControl = IsBidiFormControl(aPresContext);
mRightEdge = NS_UNCONSTRAINEDSIZE;
#endif // IBMBIDI
}
// 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(nsIPresContext* aPresContext,
const nsHTMLReflowState& aParentReflowState,
nsIFrame* aFrame,
const nsSize& aAvailableSpace,
nsReflowReason aReason,
PRBool aInit)
: mReflowDepth(aParentReflowState.mReflowDepth + 1),
mFlags(aParentReflowState.mFlags)
{
parentReflowState = &aParentReflowState;
frame = aFrame;
reason = aReason;
if (reason == eReflowReason_Incremental) {
// If the child frame isn't along the reflow path, then convert
// the incremental reflow to a dirty reflow.
path = aParentReflowState.path->GetSubtreeFor(aFrame);
if (! path)
reason = eReflowReason_Dirty;
}
else
path = nsnull;
availableWidth = aAvailableSpace.width;
availableHeight = aAvailableSpace.height;
rendContext = aParentReflowState.rendContext;
mSpaceManager = aParentReflowState.mSpaceManager;
mLineLayout = aParentReflowState.mLineLayout;
mFlags.mIsTopOfPage = aParentReflowState.mFlags.mIsTopOfPage;
mPercentHeightObserver = (aParentReflowState.mPercentHeightObserver &&
aParentReflowState.mPercentHeightObserver->NeedsToObserve(*this))
? aParentReflowState.mPercentHeightObserver : nsnull;
mPercentHeightReflowInitiator = aParentReflowState.mPercentHeightReflowInitiator;
if (aInit) {
Init(aPresContext);
}
#ifdef IBMBIDI
mFlags.mVisualBidiFormControl = (aParentReflowState.mFlags.mVisualBidiFormControl) ?
PR_TRUE : IsBidiFormControl(aPresContext);
mRightEdge = aParentReflowState.mRightEdge;
#endif // IBMBIDI
}
// Same as the previous except that the reason is taken from the
// parent's reflow state.
nsHTMLReflowState::nsHTMLReflowState(nsIPresContext* aPresContext,
const nsHTMLReflowState& aParentReflowState,
nsIFrame* aFrame,
const nsSize& aAvailableSpace)
: mReflowDepth(aParentReflowState.mReflowDepth + 1),
mFlags(aParentReflowState.mFlags)
{
parentReflowState = &aParentReflowState;
frame = aFrame;
reason = aParentReflowState.reason;
if (reason == eReflowReason_Incremental) {
// If the child frame isn't along the reflow path, then convert
// the incremental reflow to a dirty reflow.
path = aParentReflowState.path->GetSubtreeFor(aFrame);
if (! path)
reason = eReflowReason_Dirty;
}
else
path = nsnull;
availableWidth = aAvailableSpace.width;
availableHeight = aAvailableSpace.height;
rendContext = aParentReflowState.rendContext;
mSpaceManager = aParentReflowState.mSpaceManager;
mLineLayout = aParentReflowState.mLineLayout;
mFlags.mIsTopOfPage = aParentReflowState.mFlags.mIsTopOfPage;
mPercentHeightObserver = (aParentReflowState.mPercentHeightObserver &&
aParentReflowState.mPercentHeightObserver->NeedsToObserve(*this))
? aParentReflowState.mPercentHeightObserver : nsnull;
mPercentHeightReflowInitiator = aParentReflowState.mPercentHeightReflowInitiator;
Init(aPresContext);
#ifdef IBMBIDI
mFlags.mVisualBidiFormControl = (aParentReflowState.mFlags.mVisualBidiFormControl) ?
PR_TRUE : IsBidiFormControl(aPresContext);
mRightEdge = aParentReflowState.mRightEdge;
#endif // IBMBIDI
}
// Version that species the containing block width and height
nsHTMLReflowState::nsHTMLReflowState(nsIPresContext* aPresContext,
const nsHTMLReflowState& aParentReflowState,
nsIFrame* aFrame,
const nsSize& aAvailableSpace,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight,
nsReflowReason aReason)
: mReflowDepth(aParentReflowState.mReflowDepth + 1),
mFlags(aParentReflowState.mFlags)
{
parentReflowState = &aParentReflowState;
frame = aFrame;
reason = aReason;
if (reason == eReflowReason_Incremental) {
// If the child frame isn't along the reflow path, then convert
// the incremental reflow to a dirty reflow.
path = aParentReflowState.path->GetSubtreeFor(aFrame);
if (! path)
reason = eReflowReason_Dirty;
}
else
path = nsnull;
availableWidth = aAvailableSpace.width;
availableHeight = aAvailableSpace.height;
rendContext = aParentReflowState.rendContext;
mSpaceManager = aParentReflowState.mSpaceManager;
mLineLayout = aParentReflowState.mLineLayout;
mFlags.mIsTopOfPage = aParentReflowState.mFlags.mIsTopOfPage;
mPercentHeightObserver = (aParentReflowState.mPercentHeightObserver &&
aParentReflowState.mPercentHeightObserver->NeedsToObserve(*this))
? aParentReflowState.mPercentHeightObserver : nsnull;
mPercentHeightReflowInitiator = aParentReflowState.mPercentHeightReflowInitiator;
Init(aPresContext, aContainingBlockWidth, aContainingBlockHeight);
#ifdef IBMBIDI
mFlags.mVisualBidiFormControl = (aParentReflowState.mFlags.mVisualBidiFormControl) ?
PR_TRUE : IsBidiFormControl(aPresContext);
mRightEdge = aParentReflowState.mRightEdge;
#endif // IBMBIDI
}
void
nsHTMLReflowState::Init(nsIPresContext* aPresContext,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight,
nsMargin* aBorder,
nsMargin* aPadding)
{
mCompactMarginWidth = 0;
#ifdef DEBUG
mDebugHook = nsnull;
#endif
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);
}
void nsHTMLReflowState::InitCBReflowState()
{
PRBool isContainingBlock;
nsresult rv = frame->IsPercentageBase(isContainingBlock);
if (NS_SUCCEEDED(rv) && isContainingBlock) {
// a block inside a table cell needs to use the table cell
if (parentReflowState) {
if (IS_TABLE_CELL(parentReflowState->frame->GetType())) {
mCBReflowState = parentReflowState;
return;
}
}
mCBReflowState = this;
return;
}
mCBReflowState = parentReflowState->mCBReflowState;
}
const nsHTMLReflowState*
nsHTMLReflowState::GetPageBoxReflowState(const nsHTMLReflowState* aParentRS)
{
// XXX write me as soon as we can ask a frame if it's a page frame...
return nsnull;
}
nscoord
nsHTMLReflowState::GetContainingBlockContentWidth(const nsHTMLReflowState* aParentRS)
{
const nsHTMLReflowState* rs = aParentRS->mCBReflowState;
if (!rs)
return 0;
return rs->mComputedWidth;
}
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 {
NS_ASSERTION(NS_STYLE_FLOAT_NONE != disp->mFloats,
"unknown out of flow frame type");
frameType = NS_CSS_FRAME_TYPE_FLOATING;
}
}
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_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->GetStateBits() & NS_FRAME_REPLACED_ELEMENT) {
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) {
const nsStyleVisibility* vis = frame->GetStyleVisibility();
if (NS_STYLE_DIRECTION_LTR == vis->mDirection) {
rightIsAuto = PR_TRUE;
} else {
leftIsAuto = 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
ComputeHorizontalValue(aContainingBlockWidth,
mStylePosition->mOffset.GetRightUnit(),
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
ComputeHorizontalValue(aContainingBlockWidth,
mStylePosition->mOffset.GetLeftUnit(),
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
ComputeVerticalValue(aContainingBlockHeight,
mStylePosition->mOffset.GetBottomUnit(),
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
ComputeVerticalValue(aContainingBlockHeight,
mStylePosition->mOffset.GetTopUnit(),
mStylePosition->mOffset.GetTop(coord),
mComputedOffsets.top);
// Computed value for 'bottom' is minus the value of 'top'
mComputedOffsets.bottom = -mComputedOffsets.top;
}
}
// Returns the nearest containing block frame for the specified frame.
// Also returns the left, top, right, and bottom edges of the specified
// frame's content area. These are in the coordinate space of the block
// frame itself
static nsIFrame*
GetNearestContainingBlock(nsIFrame* aFrame, nsMargin& aContentArea)
{
aFrame = aFrame->GetParent();
while (aFrame) {
nsIAtom* frameType = aFrame->GetType();
PRBool isBlock =
(frameType == nsLayoutAtoms::blockFrame) ||
(frameType == nsLayoutAtoms::areaFrame);
if (isBlock) {
break;
}
aFrame = aFrame->GetParent();
}
if (aFrame) {
nsSize size = aFrame->GetSize();
aContentArea.left = 0;
aContentArea.top = 0;
aContentArea.right = size.width;
aContentArea.bottom = size.height;
// Subtract off for border and padding. If it can't be computed because
// it's percentage based (for example) then just ignore it
nsStyleBorderPadding bPad;
nsMargin borderPadding;
nsStyleContext* styleContext = aFrame->GetStyleContext();
styleContext->GetBorderPaddingFor(bPad);
if (bPad.GetBorderPadding(borderPadding)) {
aContentArea.left += borderPadding.left;
aContentArea.top += borderPadding.top;
aContentArea.right -= borderPadding.right;
aContentArea.bottom -= borderPadding.bottom;
}
}
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() == nsLayoutAtoms::imageFrame) {
nsImageFrame* imageFrame = (nsImageFrame*)aFrame;
imageFrame->GetIntrinsicImageSize(aIntrinsicSize);
result = (aIntrinsicSize != nsSize(0, 0));
}
return result;
}
nscoord
nsHTMLReflowState::CalculateHorizBorderPaddingMargin(nscoord aContainingBlockWidth)
{
nsMargin border, padding, margin;
// Get the border
if (!mStyleBorder->GetBorder(border)) {
// CSS2 has no percentage borders
border.SizeTo(0, 0, 0, 0);
}
// 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
ComputeHorizontalValue(aContainingBlockWidth,
mStylePadding->mPadding.GetLeftUnit(),
mStylePadding->mPadding.GetLeft(left),
padding.left);
ComputeHorizontalValue(aContainingBlockWidth,
mStylePadding->mPadding.GetRightUnit(),
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()) {
margin.left = 0; // just ignore
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleMargin->mMargin.GetLeftUnit(),
mStyleMargin->mMargin.GetLeft(left),
margin.left);
}
if (eStyleUnit_Auto == mStyleMargin->mMargin.GetRightUnit()) {
margin.right = 0; // just ignore
} else {
ComputeHorizontalValue(aContainingBlockWidth,
mStyleMargin->mMargin.GetRightUnit(),
mStyleMargin->mMargin.GetRight(right),
margin.right);
}
}
return padding.left + padding.right + border.left + border.right +
margin.left + margin.right;
}
static void
GetPlaceholderOffset(nsIFrame* aPlaceholderFrame,
nsIFrame* aBlockFrame,
nsPoint& aOffset)
{
aOffset = aPlaceholderFrame->GetPosition();
// Convert the placeholder position to the coordinate space of the block
// frame that contains it
nsIFrame* parent = aPlaceholderFrame->GetParent();
while (parent && (parent != aBlockFrame)) {
aOffset += parent->GetPosition();
parent = parent->GetParent();
}
}
static nsIFrame*
FindImmediateChildOf(nsIFrame* aParent, nsIFrame* aDescendantFrame)
{
nsIFrame* result = aDescendantFrame;
while (result) {
nsIFrame* parent = result->GetParent();
if (parent == aParent) {
break;
}
// The frame is not an immediate child of aParent so walk up another level
result = parent;
}
return result;
}
// 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(nsIPresContext* aPresContext,
nsIFrame* aPlaceholderFrame,
nsIFrame* aBlockFrame,
nsMargin& aBlockContentArea,
nsIFrame* aAbsoluteContainingBlockFrame,
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
nsStyleUnit widthUnit = mStylePosition->mWidth.GetUnit();
nsSize intrinsicSize;
PRBool knowIntrinsicSize = PR_FALSE;
if (NS_FRAME_IS_REPLACED(mFrameType) && (eStyleUnit_Auto == widthUnit)) {
// 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
nscoord horizBorderPaddingMargin;
// 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
horizBorderPaddingMargin = CalculateHorizBorderPaddingMargin(aBlockContentArea.right -
aBlockContentArea.left);
if (NS_FRAME_IS_REPLACED(mFrameType) && (eStyleUnit_Auto == widthUnit)) {
// 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 + horizBorderPaddingMargin;
knowBoxWidth = PR_TRUE;
}
} else if (eStyleUnit_Auto == widthUnit) {
// The box width is the containing block width
boxWidth = aBlockContentArea.right - aBlockContentArea.left;
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
ComputeHorizontalValue(aBlockContentArea.right - aBlockContentArea.left,
widthUnit, mStylePosition->mWidth, boxWidth);
boxWidth += horizBorderPaddingMargin;
knowBoxWidth = PR_TRUE;
}
}
// Get the 'direction' of the block
const nsStyleVisibility* blockVis = aBlockFrame->GetStyleVisibility();
// Get the placeholder x-offset and y-offset in the coordinate
// space of the block frame that contains it
nsPoint placeholderOffset;
GetPlaceholderOffset(aPlaceholderFrame, aBlockFrame, placeholderOffset);
// First, determine the hypothetical box's mTop
if (aBlockFrame) {
// We need the immediate child of the block frame, and that may not be
// the placeholder frame
nsBlockFrame* blockFrame = NS_STATIC_CAST(nsBlockFrame*, aBlockFrame);
nsIFrame *blockChild = FindImmediateChildOf(aBlockFrame, 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 why the special-casing if we are the last line box?
if (lineBox != blockFrame->end_lines()) {
nsIFrame * firstFrame = lineBox->mFirstChild;
while (firstFrame != aPlaceholderFrame) {
NS_ASSERTION(firstFrame, "Must reach our placeholder before end of list!");
if (!firstFrame) // This can be removed when we split out-of-flow
break; // frames correctly, see bug 223064
if (!firstFrame->IsEmpty()) {
break;
}
firstFrame = firstFrame->GetNextSibling();
}
if (firstFrame == aPlaceholderFrame) {
// 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;
}
}
}
// 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 = aBlockContentArea.left;
}
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 = aBlockContentArea.right;
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 = aBlockContentArea.right;
}
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 = aBlockContentArea.left;
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
if (aBlockFrame != aAbsoluteContainingBlockFrame) {
nsIFrame* parent = aBlockFrame;
do {
nsPoint origin = parent->GetPosition();
aHypotheticalBox.mLeft += origin.x;
aHypotheticalBox.mRight += origin.x;
aHypotheticalBox.mTop += origin.y;
// Move up the tree one level
parent = parent->GetParent();
} while (parent && (parent != aAbsoluteContainingBlockFrame));
}
// 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
const nsStyleBorder* borderStyle =
aAbsoluteContainingBlockFrame->GetStyleBorder();
nsMargin border;
if (!borderStyle->GetBorder(border)) {
NS_NOTYETIMPLEMENTED("percentage border");
}
aHypotheticalBox.mLeft -= border.left;
aHypotheticalBox.mRight -= border.left;
aHypotheticalBox.mTop -= border.top;
}
void
nsHTMLReflowState::InitAbsoluteConstraints(nsIPresContext* 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 content area left, top, right, and bottom edges
nsMargin blockContentArea;
nsIFrame* blockFrame = GetNearestContainingBlock(placeholderFrame,
blockContentArea);
// 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, blockFrame,
blockContentArea, cbrs->frame, 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 {
ComputeHorizontalValue(containingBlockWidth, mStylePosition->mOffset.GetLeftUnit(),
mStylePosition->mOffset.GetLeft(coord),
mComputedOffsets.left);
}
if (eStyleUnit_Auto == mStylePosition->mOffset.GetRightUnit()) {
mComputedOffsets.right = 0;
rightIsAuto = PR_TRUE;
} else {
ComputeHorizontalValue(containingBlockWidth, mStylePosition->mOffset.GetRightUnit(),
mStylePosition->mOffset.GetRight(coord),
mComputedOffsets.right);
}
// When the CSS2 spec refers to direction it means the containing block's
// direction and not the direction of the absolutely positioned element itself
PRUint8 direction = cbrs->mStyleVisibility->mDirection;
// Initialize the 'width' computed value
nsStyleUnit widthUnit = mStylePosition->mWidth.GetUnit();
PRBool widthIsAuto = (eStyleUnit_Auto == widthUnit);
if (!widthIsAuto) {
// Use the specified value for the computed width
ComputeHorizontalValue(containingBlockWidth, widthUnit,
mStylePosition->mWidth, mComputedWidth);
AdjustComputedWidth(PR_TRUE);
}
// See if none of 'left', 'width', and 'right', is 'auto'
if (!leftIsAuto && !widthIsAuto && !rightIsAuto) {
// See whether we're over-constrained
PRInt32 availBoxSpace = containingBlockWidth - mComputedOffsets.left - mComputedOffsets.right;
PRInt32 availContentSpace = availBoxSpace - mComputedBorderPadding.left -
mComputedBorderPadding.right;
if (availContentSpace < mComputedWidth) {
// We're over-constrained so use 'direction' to dictate which value to
// ignore
if (NS_STYLE_DIRECTION_LTR == direction) {
// Ignore the specified value for 'right'
mComputedOffsets.right = containingBlockWidth - mComputedOffsets.left -
mComputedBorderPadding.left - mComputedWidth - mComputedBorderPadding.right;
} else {
// Ignore the specified value for 'left'
mComputedOffsets.left = containingBlockWidth - mComputedBorderPadding.left -
mComputedWidth - mComputedBorderPadding.right - mComputedOffsets.right;
}
} else {
// Calculate any 'auto' margin values
PRBool marginLeftIsAuto = (eStyleUnit_Auto == mStyleMargin->mMargin.GetLeftUnit());
PRBool marginRightIsAuto = (eStyleUnit_Auto == mStyleMargin->mMargin.GetRightUnit());
PRInt32 availMarginSpace = availContentSpace - mComputedWidth;
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;
}
}
} else {
// See if all three of 'left', 'width', and 'right', are 'auto'
if (leftIsAuto && widthIsAuto && 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;
}
}
}
// At this point we know that at least one of 'left', 'width', and 'right'
// is 'auto', but not all three. Examine the various combinations
if (widthIsAuto) {
if (leftIsAuto || rightIsAuto) {
if (NS_FRAME_IS_REPLACED(mFrameType)) {
// For a replaced element we use the intrinsic size
mComputedWidth = NS_INTRINSICSIZE;
} else {
// The width is shrink-to-fit but constrained by the containing block width
mComputedWidth = NS_SHRINKWRAPWIDTH;
PRInt32 maxWidth = containingBlockWidth;
if (NS_UNCONSTRAINEDSIZE != maxWidth) {
maxWidth -= mComputedOffsets.left + mComputedMargin.left + mComputedBorderPadding.left +
mComputedBorderPadding.right + mComputedMargin.right + mComputedOffsets.right;
}
if (maxWidth <= 0) {
maxWidth = 1;
}
if (mComputedMaxWidth > maxWidth) {
mComputedMaxWidth = maxWidth;
}
}
if (leftIsAuto) {
mComputedOffsets.left = NS_AUTOOFFSET; // solve for 'left'
} else {
mComputedOffsets.right = NS_AUTOOFFSET; // solve for 'right'
}
} else {
// Only 'width' is 'auto' so just solve for 'width'
mComputedWidth = containingBlockWidth - mComputedOffsets.left -
mComputedMargin.left - mComputedBorderPadding.left -
mComputedBorderPadding.right -
mComputedMargin.right - mComputedOffsets.right;
AdjustComputedWidth(PR_FALSE);
// XXX If the direction is rtl then we need to reevaluate left...
}
} else {
// Either 'left' or 'right' or both is 'auto'
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;
}
}
}
if (leftIsAuto) {
// Solve for 'left'
mComputedOffsets.left = containingBlockWidth - mComputedMargin.left -
mComputedBorderPadding.left - mComputedWidth - mComputedBorderPadding.right -
mComputedMargin.right - mComputedOffsets.right;
} else if (rightIsAuto) {
// Solve for 'right'
mComputedOffsets.right = containingBlockWidth - mComputedOffsets.left -
mComputedMargin.left - mComputedBorderPadding.left - mComputedWidth -
mComputedBorderPadding.right - mComputedMargin.right;
}
}
}
// Initialize the 'top' and 'bottom' computed offsets
nsStyleUnit heightUnit = mStylePosition->mHeight.GetUnit();
PRBool topIsAuto = PR_FALSE, bottomIsAuto = PR_FALSE;
if (eStyleUnit_Auto == mStylePosition->mOffset.GetTopUnit()) {
mComputedOffsets.top = 0;
topIsAuto = PR_TRUE;
} else {
nsStyleCoord c;
ComputeVerticalValue(containingBlockHeight,
mStylePosition->mOffset.GetTopUnit(),
mStylePosition->mOffset.GetTop(c),
mComputedOffsets.top);
}
if (eStyleUnit_Auto == mStylePosition->mOffset.GetBottomUnit()) {
mComputedOffsets.bottom = 0;
bottomIsAuto = PR_TRUE;
} else {
nsStyleCoord c;
ComputeVerticalValue(containingBlockHeight,
mStylePosition->mOffset.GetBottomUnit(),
mStylePosition->mOffset.GetBottom(c),
mComputedOffsets.bottom);
}
// Initialize the 'height' computed value
PRBool heightIsAuto = (eStyleUnit_Auto == heightUnit);
if (!heightIsAuto) {
// Use the specified value for the computed height
ComputeVerticalValue(containingBlockHeight, heightUnit,
mStylePosition->mHeight, mComputedHeight);
AdjustComputedHeight(PR_TRUE);
}
// See if none of 'top', 'height', and 'bottom', is 'auto'
if (!topIsAuto && !heightIsAuto && !bottomIsAuto) {
// See whether we're over-constrained
PRInt32 availBoxSpace = containingBlockHeight - mComputedOffsets.top - mComputedOffsets.bottom;
PRInt32 availContentSpace = availBoxSpace - mComputedBorderPadding.top -
mComputedBorderPadding.bottom;
if (availContentSpace < mComputedHeight) {
// We're over-constrained so ignore the specified value for 'bottom'
mComputedOffsets.bottom = containingBlockHeight - mComputedOffsets.top -
mComputedBorderPadding.top - mComputedHeight - mComputedBorderPadding.bottom;
} else {
// Calculate any 'auto' margin values
PRBool marginTopIsAuto = (eStyleUnit_Auto == mStyleMargin->mMargin.GetTopUnit());
PRBool marginBottomIsAuto = (eStyleUnit_Auto == mStyleMargin->mMargin.GetBottomUnit());
PRInt32 availMarginSpace = availContentSpace - mComputedHeight;
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;
}
}
} else {
// See if all three of 'top', 'height', and 'bottom', are 'auto'
if (topIsAuto && heightIsAuto && bottomIsAuto) {
// Treat 'top' like 'static-position'
mComputedOffsets.top = hypotheticalBox.mTop;
topIsAuto = PR_FALSE;
}
// At this point we know that at least one of 'top', 'height', and 'bottom'
// is 'auto', but not all three. Examine the various combinations
if (heightIsAuto) {
if (topIsAuto || bottomIsAuto) {
if (NS_FRAME_IS_REPLACED(mFrameType)) {
// For a replaced element we use the intrinsic size
mComputedHeight = NS_INTRINSICSIZE;
} else {
// The height is based on the content
mComputedHeight = NS_AUTOHEIGHT;
}
if (topIsAuto) {
mComputedOffsets.top = NS_AUTOOFFSET; // solve for 'top'
} else {
mComputedOffsets.bottom = NS_AUTOOFFSET; // solve for 'bottom'
}
} else {
// Only 'height' is 'auto' so just solve for 'height'
mComputedHeight = containingBlockHeight - mComputedOffsets.top -
mComputedMargin.top - mComputedBorderPadding.top -
mComputedBorderPadding.bottom -
mComputedMargin.bottom - mComputedOffsets.bottom;
AdjustComputedHeight(PR_FALSE);
}
} else {
// Either 'top' or 'bottom' or both is 'auto'
if (topIsAuto && bottomIsAuto) {
// Treat 'top' like 'static-position'
mComputedOffsets.top = hypotheticalBox.mTop;
topIsAuto = PR_FALSE;
}
if (topIsAuto) {
// Solve for 'top'
mComputedOffsets.top = containingBlockHeight - mComputedMargin.top -
mComputedBorderPadding.top - mComputedHeight - mComputedBorderPadding.bottom -
mComputedMargin.bottom - mComputedOffsets.bottom;
} else if (bottomIsAuto) {
// Solve for 'bottom'
mComputedOffsets.bottom = containingBlockHeight - mComputedOffsets.top -
mComputedMargin.top - mComputedBorderPadding.top - mComputedHeight -
mComputedBorderPadding.bottom - mComputedMargin.bottom;
}
}
}
}
static PRBool
IsInitialContainingBlock(nsIFrame* aFrame)
{
nsIContent* content = aFrame->GetContent();
if (content && !content->GetParent()) {
// The containing block corresponds to the document element so it's
// the initial containing block
return PR_TRUE;
}
return PR_FALSE;
}
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& aReflowState)
{
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 = &aReflowState;
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 (nsLayoutAtoms::blockFrame == frameType ||
nsLayoutAtoms::areaFrame == frameType ||
nsLayoutAtoms::scrollFrame == frameType) {
if (nsLayoutAtoms::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 (nsLayoutAtoms::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 (nsLayoutAtoms::scrollFrame == scrollState->frame->GetType()) {
rs = scrollState;
}
}
else if (nsLayoutAtoms::pageContentFrame == frameType) {
nsIFrame* prevInFlow;
rs->frame->GetPrevInFlow(&prevInFlow);
// 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 = (nsLayoutAtoms::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 ((nsLayoutAtoms::canvasFrame == frameType) ||
(nsLayoutAtoms::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 == nsHTMLAtoms::html, "First ancestor is not HTML");
}
}
if (secondAncestorRS) {
nsIContent* frameContent = secondAncestorRS->frame->GetContent();
if (frameContent) {
nsIAtom *contentTag = frameContent->Tag();
NS_ASSERTION(contentTag == nsHTMLAtoms::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 (nsLayoutAtoms::areaFrame == frameType) {
// make sure it is the body
if (nsLayoutAtoms::canvasFrame == rs->parentReflowState->frame->GetType()) {
result -= GetVerticalMarginBorderPadding(secondAncestorRS);
}
}
break;
}
return result;
}
// Called by InitConstraints() to compute the containing block rectangle for
// the element. Handles the special logic for absolutely positioned elements
void
nsHTMLReflowState::ComputeContainingBlockRectangle(nsIPresContext* 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) {
// The CSS2 spec says that if the ancestor is inline-level, the containing
// block depends on the 'direction' property of the ancestor. For direction
// 'ltr', it's the top and left of the content edges of the first box and
// the bottom and right content edges of the last box
//
// XXX This is a pain because it isn't top-down and it requires that we've
// completely reflowed the ancestor. It also isn't clear what happens when
// a relatively positioned ancestor is split across pages. So instead use
// the computed width and height of the nearest block-level ancestor
const nsHTMLReflowState* cbrs = aContainingBlockRS;
while (cbrs) {
nsCSSFrameType type = NS_FRAME_GET_TYPE(cbrs->mFrameType);
if ((NS_CSS_FRAME_TYPE_BLOCK == type) ||
(NS_CSS_FRAME_TYPE_FLOATING == type) ||
(NS_CSS_FRAME_TYPE_ABSOLUTE == type)) {
aContainingBlockWidth = cbrs->mComputedWidth;
aContainingBlockHeight = cbrs->mComputedHeight;
if (NS_CSS_FRAME_TYPE_ABSOLUTE == type) {
aContainingBlockWidth += cbrs->mComputedPadding.left +
cbrs->mComputedPadding.right;
aContainingBlockHeight += cbrs->mComputedPadding.top +
cbrs->mComputedPadding.bottom;
}
break;
}
cbrs = (const nsHTMLReflowState*)cbrs->parentReflowState; // XXX cast
}
} else {
// If the ancestor is block-level, the containing block is formed by the
// padding edge of the ancestor
aContainingBlockWidth += aContainingBlockRS->mComputedPadding.left +
aContainingBlockRS->mComputedPadding.right;
// 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) &&
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.top +
aContainingBlockRS->mComputedPadding.bottom;
}
}
} else {
// If this is an unconstrained reflow, then reset the containing block
// width to NS_UNCONSTRAINEDSIZE. This way percentage based values have
// no effect
if (NS_UNCONSTRAINEDSIZE == availableWidth) {
aContainingBlockWidth = NS_UNCONSTRAINEDSIZE;
}
// 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
static int PR_CALLBACK PrefsChanged(const char *aPrefName, void *instance)
{
nsCOMPtr prefs = do_GetService(NS_PREF_CONTRACTID);
if (prefs) {
PRBool boolPref;
if (NS_SUCCEEDED(prefs->GetBoolPref("browser.blink_allowed", &boolPref)))
sBlinkIsAllowed = boolPref;
}
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
nsCOMPtr prefs = do_GetService(NS_PREF_CONTRACTID);
if (prefs) {
prefs->RegisterCallback("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) {
nsCOMPtr prefs = do_GetService(NS_PREF_CONTRACTID);
PRInt32 intPref;
// browser.display.normal_lineheight_calc_control is not user changable, so
// no need to register callback for it.
if (prefs && NS_SUCCEEDED(prefs->GetIntPref(
"browser.display.normal_lineheight_calc_control", &intPref)))
sNormalLineHeightControl = NS_STATIC_CAST(eNormalLineHeightControl, intPref);
else
sNormalLineHeightControl = 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(nsIPresContext* aPresContext,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight,
nsMargin* aBorder,
nsMargin* aPadding)
{
// If this is the root frame, then set the computed width and
// height equal to the available space
if (nsnull == parentReflowState) {
mComputedWidth = availableWidth;
mComputedHeight = availableHeight;
mComputedMargin.SizeTo(0, 0, 0, 0);
mComputedPadding.SizeTo(0, 0, 0, 0);
mComputedBorderPadding.SizeTo(0, 0, 0, 0);
mComputedOffsets.SizeTo(0, 0, 0, 0);
mComputedMinWidth = mComputedMinHeight = 0;
mComputedMaxWidth = mComputedMaxHeight = NS_UNCONSTRAINEDSIZE;
} else {
// Get the containing block reflow state
const nsHTMLReflowState* cbrs = parentReflowState->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 (nsLayoutAtoms::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;
}
}
}
}
// 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, cbrs);
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, cbrs);
}
if (aBorder) { // border is an input arg
mComputedBorderPadding.top = aBorder->top;
mComputedBorderPadding.right = aBorder->right;
mComputedBorderPadding.bottom = aBorder->bottom;
mComputedBorderPadding.left = aBorder->left;
}
else {
if (!mStyleBorder->GetBorder(mComputedBorderPadding)) {
// CSS2 has no percentage borders
mComputedBorderPadding.SizeTo(0, 0, 0, 0);
}
}
mComputedBorderPadding += mComputedPadding;
nsStyleUnit widthUnit = mStylePosition->mWidth.GetUnit();
nsStyleUnit heightUnit = mStylePosition->mHeight.GetUnit();
// Check for a percentage based width and an unconstrained containing
// block width
if (eStyleUnit_Percent == widthUnit) {
if (NS_UNCONSTRAINEDSIZE == aContainingBlockWidth) {
widthUnit = eStyleUnit_Auto;
}
}
// Check for a percentage based height and a containing block height
// that depends on the content height
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) {
// 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
ComputeMinMaxValues(aContainingBlockWidth, aContainingBlockHeight, cbrs);
// Calculate the computed width and height. This varies by frame type
if ((NS_FRAME_REPLACED(NS_CSS_FRAME_TYPE_INLINE) == mFrameType) ||
(NS_FRAME_REPLACED(NS_CSS_FRAME_TYPE_FLOATING) == mFrameType)) {
// Inline replaced element and floating replaced element are basically
// treated the same. First calculate the computed width
if (eStyleUnit_Auto == widthUnit) {
// A specified value of 'auto' uses the element's intrinsic width
mComputedWidth = NS_INTRINSICSIZE;
} else {
ComputeHorizontalValue(aContainingBlockWidth, widthUnit,
mStylePosition->mWidth, mComputedWidth);
}
AdjustComputedWidth(PR_TRUE);
// Now calculate the computed height
if (eStyleUnit_Auto == heightUnit) {
// A specified value of 'auto' uses the element's intrinsic height
mComputedHeight = NS_INTRINSICSIZE;
} else {
ComputeVerticalValue(aContainingBlockHeight, heightUnit,
mStylePosition->mHeight,
mComputedHeight);
}
AdjustComputedHeight(PR_TRUE);
} else if (NS_CSS_FRAME_TYPE_FLOATING == mFrameType) {
// Floating non-replaced element. First calculate the computed width
if (eStyleUnit_Auto == widthUnit) {
if ((NS_UNCONSTRAINEDSIZE == aContainingBlockWidth) &&
(eStyleUnit_Percent == mStylePosition->mWidth.GetUnit())) {
// The element has a percentage width, but since the containing
// block width is unconstrained we set 'widthUnit' to 'auto'
// above. However, we want the element to be unconstrained, too
mComputedWidth = NS_UNCONSTRAINEDSIZE;
} else if (NS_STYLE_DISPLAY_TABLE == mStyleDisplay->mDisplay) {
// It's an outer table because an inner table is not positioned
// shrink wrap its width since the outer table is anonymous
mComputedWidth = NS_SHRINKWRAPWIDTH;
} else {
// The CSS2 spec says the computed width should be 0; however, that's
// not what Nav and IE do and even the spec doesn't really want that
// to happen.
//
// Instead, have the element shrink wrap its width
mComputedWidth = NS_SHRINKWRAPWIDTH;
// Limnit the width to the containing block width
nscoord widthFromCB = aContainingBlockWidth;
if (NS_UNCONSTRAINEDSIZE != widthFromCB) {
widthFromCB -= mComputedBorderPadding.left + mComputedBorderPadding.right +
mComputedMargin.left + mComputedMargin.right;
}
if (mComputedMaxWidth > widthFromCB) {
mComputedMaxWidth = widthFromCB;
}
}
} else {
ComputeHorizontalValue(aContainingBlockWidth, widthUnit,
mStylePosition->mWidth, mComputedWidth);
}
// Take into account minimum and maximum sizes
AdjustComputedWidth(PR_TRUE);
// Now calculate the computed height
if (eStyleUnit_Auto == heightUnit) {
mComputedHeight = NS_AUTOHEIGHT; // let it choose its height
} else {
ComputeVerticalValue(aContainingBlockHeight, heightUnit,
mStylePosition->mHeight,
mComputedHeight);
}
AdjustComputedHeight(PR_TRUE);
} else 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;
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 {
ComputeHorizontalValue(aContainingBlockWidth, widthUnit,
mStylePosition->mWidth, mComputedWidth);
}
// 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 {
ComputeVerticalValue(aContainingBlockHeight, heightUnit,
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 if (NS_CSS_FRAME_TYPE_INLINE == mFrameType) {
// Inline non-replaced elements do not have computed widths or heights
// XXX add this check to HaveFixedContentHeight/Width too
mComputedWidth = NS_UNCONSTRAINEDSIZE;
mComputedHeight = NS_UNCONSTRAINEDSIZE;
mComputedMargin.top = 0;
mComputedMargin.bottom = 0;
mComputedMinWidth = mComputedMinHeight = 0;
mComputedMaxWidth = mComputedMaxHeight = NS_UNCONSTRAINEDSIZE;
} else {
ComputeBlockBoxData(aPresContext, cbrs, widthUnit, heightUnit,
aContainingBlockWidth,
aContainingBlockHeight);
}
}
// 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);
}
}
// Compute the box data for block and block-replaced elements in the
// normal flow.
void
nsHTMLReflowState::ComputeBlockBoxData(nsIPresContext* aPresContext,
const nsHTMLReflowState* cbrs,
nsStyleUnit aWidthUnit,
nsStyleUnit aHeightUnit,
nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight)
{
// Compute the content width
if (eStyleUnit_Auto == aWidthUnit) {
if (NS_FRAME_IS_REPLACED(mFrameType)) {
// Block-level replaced element in the flow. A specified value of
// 'auto' uses the element's intrinsic width (CSS2 10.3.4)
mComputedWidth = NS_INTRINSICSIZE;
} else {
// Block-level non-replaced element in the flow. 'auto' values
// for margin-left and margin-right become 0, and the sum of the
// areas must equal the width of the content-area of the parent
// element.
if (NS_UNCONSTRAINEDSIZE == availableWidth) {
// During pass1 table reflow, auto side margin values are
// uncomputable (== 0).
mComputedWidth = NS_UNCONSTRAINEDSIZE;
} else if (NS_SHRINKWRAPWIDTH == aContainingBlockWidth) {
// The containing block should shrink wrap its width, so have
// the child block do the same
mComputedWidth = NS_UNCONSTRAINEDSIZE;
// Let its content area be as wide as the containing block's max width
// minus any margin and border/padding
nscoord maxWidth = cbrs->mComputedMaxWidth;
if (NS_UNCONSTRAINEDSIZE != maxWidth) {
maxWidth -= mComputedMargin.left + mComputedBorderPadding.left +
mComputedMargin.right + mComputedBorderPadding.right;
}
if (maxWidth < mComputedMaxWidth) {
mComputedMaxWidth = maxWidth;
}
} else {
// tables act like replaced elements regarding mComputedWidth
nsIAtom* fType = frame->GetType();
if (nsLayoutAtoms::tableOuterFrame == fType) {
mComputedWidth = 0; // XXX temp fix for trees
} else if ((nsLayoutAtoms::tableFrame == fType) ||
(nsLayoutAtoms::tableCaptionFrame == fType)) {
mComputedWidth = NS_SHRINKWRAPWIDTH;
if (eStyleUnit_Auto == mStyleMargin->mMargin.GetLeftUnit()) {
mComputedMargin.left = NS_AUTOMARGIN;
}
if (eStyleUnit_Auto == mStyleMargin->mMargin.GetRightUnit()) {
mComputedMargin.right = NS_AUTOMARGIN;
}
} else {
mComputedWidth = availableWidth - mComputedMargin.left -
mComputedMargin.right - mComputedBorderPadding.left -
mComputedBorderPadding.right;
mComputedWidth = PR_MAX(mComputedWidth, 0);
}
AdjustComputedWidth(PR_FALSE);
CalculateBlockSideMargins(cbrs->mComputedWidth, mComputedWidth);
}
}
} else {
ComputeHorizontalValue(aContainingBlockWidth, aWidthUnit,
mStylePosition->mWidth, mComputedWidth);
AdjustComputedWidth(PR_TRUE);
// Now that we have the computed-width, compute the side margins
CalculateBlockSideMargins(cbrs->mComputedWidth, mComputedWidth);
}
// Compute the content height
if (eStyleUnit_Auto == aHeightUnit) {
if (NS_FRAME_IS_REPLACED(mFrameType)) {
// For replaced elements use the intrinsic size for "auto"
mComputedHeight = NS_INTRINSICSIZE;
} else {
// For non-replaced elements auto means unconstrained
mComputedHeight = NS_UNCONSTRAINEDSIZE;
}
} else {
ComputeVerticalValue(aContainingBlockHeight, aHeightUnit,
mStylePosition->mHeight, mComputedHeight);
}
AdjustComputedHeight(PR_TRUE);
}
// 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)
{
// Because of the ugly way we do intrinsic sizing within Reflow, this method
// doesn't necessarily produce the right results. The results will be
// adjusted in nsBlockReflowContext::AlignBlockHorizontally after reflow.
// The code for tables is particularly sensitive to regressions; the
// numerous |isTable| checks are technically incorrect, but necessary
// for basic testcases.
// We can only provide values for auto side margins in a constrained
// reflow. For unconstrained reflow there is no effective width to
// compute against...
if (NS_UNCONSTRAINEDSIZE == aComputedWidth ||
NS_UNCONSTRAINEDSIZE == aAvailWidth)
return;
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.
PRBool isTable = mStyleDisplay->mDisplay == NS_STYLE_DISPLAY_TABLE ||
mStyleDisplay->mDisplay == NS_STYLE_DISPLAY_TABLE_CAPTION;
// Calculate how much space is available for margins
nscoord availMarginSpace = aAvailWidth - sum;
// XXXldb Should this be quirks-mode only? And why captions?
if (isTable)
// XXXldb Why does this break things so badly if this is changed to
// availMarginSpace += mComputedBorderPadding.left +
// mComputedBorderPadding.right;
availMarginSpace = aAvailWidth - aComputedWidth;
// If the available margin space is negative, then don't follow the
// usual overconstraint rules.
if (availMarginSpace < 0) {
if (!isTable) {
if (mStyleVisibility->mDirection == NS_STYLE_DIRECTION_LTR) {
mComputedMargin.right += availMarginSpace;
} else {
mComputedMargin.left += availMarginSpace;
}
} else {
mComputedMargin.left = 0;
mComputedMargin.right = 0;
if (mStyleVisibility->mDirection == NS_STYLE_DIRECTION_RTL) {
mComputedMargin.left = 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 && !isTable) {
// 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 (prs &&
(prs->mStyleText->mTextAlign == NS_STYLE_TEXT_ALIGN_MOZ_CENTER ||
prs->mStyleText->mTextAlign == NS_STYLE_TEXT_ALIGN_MOZ_RIGHT)) {
isAutoLeftMargin = PR_TRUE;
isAutoRightMargin =
prs->mStyleText->mTextAlign == NS_STYLE_TEXT_ALIGN_MOZ_CENTER;
}
// Otherwise apply the CSS rules, and ignore one margin by forcing
// it to 'auto', depending on 'direction'.
else if (NS_STYLE_DIRECTION_LTR == mStyleVisibility->mDirection) {
isAutoRightMargin = PR_TRUE;
}
else {
isAutoLeftMargin = 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;
}
}
PRBool
nsHTMLReflowState::UseComputedHeight()
{
static PRBool useComputedHeight = PR_FALSE;
#if defined(XP_UNIX) || defined(XP_WIN) || defined(XP_OS2) || defined(XP_BEOS)
static PRBool firstTime = 1;
if (firstTime) {
if (getenv("GECKO_USE_COMPUTED_HEIGHT")) {
useComputedHeight = PR_TRUE;
}
firstTime = 0;
}
#endif
return useComputedHeight;
}
#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;
}
static nscoord
ComputeLineHeight(nsIPresContext* aPresContext,
nsIRenderingContext* aRenderingContext,
nsStyleContext* aStyleContext)
{
NS_PRECONDITION(nsnull != aRenderingContext, "no rendering context");
nscoord lineHeight = -1;
const nsStyleText* text = aStyleContext->GetStyleText();
const nsStyleFont* font = aStyleContext->GetStyleFont();
const nsStyleVisibility* vis = aStyleContext->GetStyleVisibility();
nsStyleUnit unit = text->mLineHeight.GetUnit();
if (unit == eStyleUnit_Coord) {
// For length values just use the pre-computed value
lineHeight = text->mLineHeight.GetCoordValue();
} else {
nsCOMPtr deviceContext;
aRenderingContext->GetDeviceContext(*getter_AddRefs(deviceContext));
nsCOMPtr langGroup;
if (vis->mLanguage) {
vis->mLanguage->GetLanguageGroup(getter_AddRefs(langGroup));
}
nsCOMPtr fm;
deviceContext->GetMetricsFor(font->mFont, langGroup, *getter_AddRefs(fm));
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 actual
// em height.
float factor;
factor = text->mLineHeight.GetFactorValue();
// Note: we normally use the actual font height for computing the
// line-height raw value from the style context. On systems where
// they disagree the actual font height is more appropriate. This
// little hack lets us override that behavior to allow for more
// precise layout in the face of imprecise fonts.
nscoord emHeight = font->mFont.size;
if (!nsHTMLReflowState::UseComputedHeight()) {
fm->GetEmHeight(emHeight);
}
lineHeight = NSToCoordRound(factor * emHeight);
} else {
NS_ASSERTION(eStyleUnit_Normal == unit, "bad unit");
lineHeight = font->mFont.size;
if (!nsHTMLReflowState::UseComputedHeight()) {
lineHeight = GetNormalLineHeight(fm);
}
}
}
return lineHeight;
}
nscoord
nsHTMLReflowState::CalcLineHeight(nsIPresContext* aPresContext,
nsIRenderingContext* aRenderingContext,
nsIFrame* aFrame)
{
nscoord lineHeight = -1;
nsStyleContext* sc = aFrame->GetStyleContext();
if (sc) {
lineHeight = ComputeLineHeight(aPresContext, aRenderingContext, sc);
}
if (lineHeight < 0) {
// Negative line-heights are not allowed by the spec. Translate
// them into "normal" when found.
const nsStyleFont* font = sc->GetStyleFont();
if (UseComputedHeight()) {
lineHeight = font->mFont.size;
}
else {
SetFontFromStyle(aRenderingContext, sc);
nsCOMPtr fm;
aRenderingContext->GetFontMetrics(*getter_AddRefs(fm));
if (fm) {
lineHeight = GetNormalLineHeight(fm);
}
}
}
return lineHeight;
}
void
nsHTMLReflowState::ComputeHorizontalValue(nscoord aContainingBlockWidth,
nsStyleUnit aUnit,
const nsStyleCoord& aCoord,
nscoord& aResult)
{
aResult = 0;
if (eStyleUnit_Percent == aUnit) {
if (NS_UNCONSTRAINEDSIZE == aContainingBlockWidth) {
aResult = 0;
} else {
float pct = aCoord.GetPercentValue();
aResult = NSToCoordFloor(aContainingBlockWidth * pct);
}
} else if (eStyleUnit_Coord == aUnit) {
aResult = aCoord.GetCoordValue();
}
else if (eStyleUnit_Chars == aUnit) {
if ((nsnull == rendContext) || (nsnull == frame)) {
// We can't compute it without a rendering context or frame, so
// pretend its zero...
}
else {
nsStyleContext* styleContext = frame->GetStyleContext();
SetFontFromStyle(rendContext, styleContext);
nscoord fontWidth;
rendContext->GetWidth('M', fontWidth);
aResult = aCoord.GetIntValue() * fontWidth;
}
}
}
void
nsHTMLReflowState::ComputeVerticalValue(nscoord aContainingBlockHeight,
nsStyleUnit aUnit,
const nsStyleCoord& aCoord,
nscoord& aResult)
{
aResult = 0;
if (eStyleUnit_Percent == aUnit) {
// Verify no one is trying to calculate a percentage based height against
// a height that's shrink wrapping to its content. In that case they should
// treat the specified value like 'auto'
NS_ASSERTION(NS_AUTOHEIGHT != aContainingBlockHeight, "unexpected containing block height");
if (NS_AUTOHEIGHT!=aContainingBlockHeight)
{
float pct = aCoord.GetPercentValue();
aResult = NSToCoordFloor(aContainingBlockHeight * pct);
}
else { // safest thing to do for an undefined height is to make it 0
aResult = 0;
}
} else if (eStyleUnit_Coord == aUnit) {
aResult = aCoord.GetCoordValue();
}
}
void
nsHTMLReflowState::ComputeMargin(nscoord aContainingBlockWidth,
const nsHTMLReflowState* aContainingBlockRS)
{
// If style style can provide us the margin directly, then use it.
if (!mStyleMargin->GetMargin(mComputedMargin)) {
// We have to compute the value
if (NS_UNCONSTRAINEDSIZE == aContainingBlockWidth) {
mComputedMargin.left = 0;
mComputedMargin.right = 0;
if (eStyleUnit_Coord == mStyleMargin->mMargin.GetLeftUnit()) {
nsStyleCoord left;
mStyleMargin->mMargin.GetLeft(left),
mComputedMargin.left = left.GetCoordValue();
}
if (eStyleUnit_Coord == mStyleMargin->mMargin.GetRightUnit()) {
nsStyleCoord right;
mStyleMargin->mMargin.GetRight(right),
mComputedMargin.right = right.GetCoordValue();
}
} else {
nsStyleCoord left, right;
ComputeHorizontalValue(aContainingBlockWidth,
mStyleMargin->mMargin.GetLeftUnit(),
mStyleMargin->mMargin.GetLeft(left),
mComputedMargin.left);
ComputeHorizontalValue(aContainingBlockWidth,
mStyleMargin->mMargin.GetRightUnit(),
mStyleMargin->mMargin.GetRight(right),
mComputedMargin.right);
}
const nsHTMLReflowState* rs2 = GetPageBoxReflowState(parentReflowState);
nsStyleCoord top, bottom;
if (nsnull != rs2) {
// According to the CSS2 spec, margin percentages are
// calculated with respect to the *height* of the containing
// block when in a paginated context.
ComputeVerticalValue(rs2->mComputedHeight,
mStyleMargin->mMargin.GetTopUnit(),
mStyleMargin->mMargin.GetTop(top),
mComputedMargin.top);
ComputeVerticalValue(rs2->mComputedHeight,
mStyleMargin->mMargin.GetBottomUnit(),
mStyleMargin->mMargin.GetBottom(bottom),
mComputedMargin.bottom);
}
else {
// 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.
ComputeHorizontalValue(aContainingBlockWidth,
mStyleMargin->mMargin.GetTopUnit(),
mStyleMargin->mMargin.GetTop(top),
mComputedMargin.top);
ComputeHorizontalValue(aContainingBlockWidth,
mStyleMargin->mMargin.GetBottomUnit(),
mStyleMargin->mMargin.GetBottom(bottom),
mComputedMargin.bottom);
}
}
}
void
nsHTMLReflowState::ComputePadding(nscoord aContainingBlockWidth,
const nsHTMLReflowState* aContainingBlockRS)
{
// If style can provide us the padding directly, then use it.
if (!mStylePadding->GetPadding(mComputedPadding)) {
// We have to compute the value
nsStyleCoord left, right, top, bottom;
ComputeHorizontalValue(aContainingBlockWidth,
mStylePadding->mPadding.GetLeftUnit(),
mStylePadding->mPadding.GetLeft(left),
mComputedPadding.left);
ComputeHorizontalValue(aContainingBlockWidth,
mStylePadding->mPadding.GetRightUnit(),
mStylePadding->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
ComputeHorizontalValue(aContainingBlockWidth,
mStylePadding->mPadding.GetTopUnit(),
mStylePadding->mPadding.GetTop(top),
mComputedPadding.top);
ComputeHorizontalValue(aContainingBlockWidth,
mStylePadding->mPadding.GetBottomUnit(),
mStylePadding->mPadding.GetBottom(bottom),
mComputedPadding.bottom);
}
// a table row/col group, row/col doesn't have padding
if (frame) {
nsIAtom* frameType = frame->GetType();
if ((nsLayoutAtoms::tableRowGroupFrame == frameType) ||
(nsLayoutAtoms::tableColGroupFrame == frameType) ||
(nsLayoutAtoms::tableRowFrame == frameType) ||
(nsLayoutAtoms::tableColFrame == frameType)) {
mComputedPadding.top = 0;
mComputedPadding.right = 0;
mComputedPadding.bottom = 0;
mComputedPadding.left = 0;
}
}
}
void
nsHTMLReflowState::ComputeMinMaxValues(nscoord aContainingBlockWidth,
nscoord aContainingBlockHeight,
const nsHTMLReflowState* aContainingBlockRS)
{
nsStyleUnit minWidthUnit = mStylePosition->mMinWidth.GetUnit();
ComputeHorizontalValue(aContainingBlockWidth, minWidthUnit,
mStylePosition->mMinWidth, mComputedMinWidth);
nsStyleUnit maxWidthUnit = mStylePosition->mMaxWidth.GetUnit();
if (eStyleUnit_Null == maxWidthUnit) {
// Specified value of 'none'
mComputedMaxWidth = NS_UNCONSTRAINEDSIZE; // no limit
} else {
ComputeHorizontalValue(aContainingBlockWidth, maxWidthUnit,
mStylePosition->mMaxWidth, mComputedMaxWidth);
}
// 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;
}
nsStyleUnit minHeightUnit = mStylePosition->mMinHeight.GetUnit();
// 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 == minHeightUnit)) {
mComputedMinHeight = 0;
} else {
ComputeVerticalValue(aContainingBlockHeight, minHeightUnit,
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 {
ComputeVerticalValue(aContainingBlockHeight, maxHeightUnit,
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::AdjustComputedHeight(PRBool aAdjustForBoxSizing)
{
// only do the math if the height is not a symbolic value
if (mComputedHeight == NS_UNCONSTRAINEDSIZE) {
return;
}
NS_ASSERTION(mComputedHeight >= 0, "Negative Height Input - very bad");
// Factor in any minimum and maximum size information
if (mComputedHeight > mComputedMaxHeight) {
mComputedHeight = mComputedMaxHeight;
} else if (mComputedHeight < mComputedMinHeight) {
mComputedHeight = mComputedMinHeight;
}
if (aAdjustForBoxSizing) {
// remove extra padding/border if box-sizing property is set
switch (mStylePosition->mBoxSizing) {
case NS_STYLE_BOX_SIZING_PADDING : {
mComputedHeight -= mComputedPadding.top + mComputedPadding.bottom;
break;
}
case NS_STYLE_BOX_SIZING_BORDER : {
mComputedHeight -= mComputedBorderPadding.top + mComputedBorderPadding.bottom;
}
default : break;
}
// If it did go bozo because of too much border or padding, set to 0
if(mComputedHeight < 0) mComputedHeight = 0;
}
}
void nsHTMLReflowState::AdjustComputedWidth(PRBool aAdjustForBoxSizing)
{
// only do the math if the width is not a symbolic value
if (mComputedWidth == NS_UNCONSTRAINEDSIZE) {
return;
}
NS_ASSERTION(mComputedWidth >= 0, "Negative Width Input - very bad");
// Factor in any minimum and maximum size information
if (mComputedWidth > mComputedMaxWidth) {
mComputedWidth = mComputedMaxWidth;
} else if (mComputedWidth < mComputedMinWidth) {
mComputedWidth = mComputedMinWidth;
}
if (aAdjustForBoxSizing) {
// remove extra padding/border if box-sizing property is set
switch (mStylePosition->mBoxSizing) {
case NS_STYLE_BOX_SIZING_PADDING : {
mComputedWidth -= mComputedPadding.left + mComputedPadding.right;
break;
}
case NS_STYLE_BOX_SIZING_BORDER : {
mComputedWidth -= mComputedBorderPadding.left + mComputedBorderPadding.right;
}
default : break;
}
// If it did go bozo because of too much border or padding, set to 0
if(mComputedWidth < 0) mComputedWidth = 0;
}
}
#ifdef IBMBIDI
PRBool
nsHTMLReflowState::IsBidiFormControl(nsIPresContext* aPresContext)
{
// This check is only necessary on visual bidi pages, because most
// visual pages use logical order for form controls so that they will
// display correctly on native widgets in OSs with Bidi support.
// So bail out if the page is not Bidi, or not visual, or if the pref is
// set to use visual order on forms in visual pages
PRBool bidiEnabled;
aPresContext->GetBidiEnabled(&bidiEnabled);
if (!bidiEnabled) {
return PR_FALSE;
}
PRBool isVisual;
aPresContext->IsVisualMode(isVisual);
if (!isVisual) {
return PR_FALSE;
}
PRUint32 options;
aPresContext->GetBidi(&options);
if (IBMBIDI_CONTROLSTEXTMODE_LOGICAL != GET_BIDI_OPTION_CONTROLSTEXTMODE(options)) {
return PR_FALSE;
}
nsIContent* content = frame->GetContent();
if (!content) {
return PR_FALSE;
}
// If this is a root reflow, we have to walk up the content tree to
// find out if the reflow root is a descendant of a form control.
// Otherwise, just test this content node
if (mReflowDepth == 0) {
for ( ; content; content = content->GetParent()) {
if (content->IsContentOfType(nsIContent::eHTML_FORM_CONTROL)) {
return PR_TRUE;
}
}
} else {
return (content->IsContentOfType(nsIContent::eHTML_FORM_CONTROL));
}
return PR_FALSE;
}
#endif